Basics of Environmental studies · 2110007 – ES – Study Material 2 Contents 1 INTRODUCTION TO...

DARSHAN INSTITUTE OF ENGINEERING

AND TECHNOLOGY

Basics of Environmental studies

2110007 – ES – Study Material

2

Contents 1 INTRODUCTION TO ENVIRONMENT, ECOLOGY & ECOSYSTEM ..................................................... 8

1.1 Environment: ........................................................................................................................... 8

1.2 Ecology: ................................................................................................................................... 8

1.3 Ecosystem: ............................................................................................................................... 8

1.4 Components of Environment: ................................................................................................. 8

1.4.1 Atmosphere: - .................................................................................................................. 8

1.4.2 Hydrosphere: ................................................................................................................... 9

1.4.3 Lithosphere: ..................................................................................................................... 9

1.4.4 Biosphere: ........................................................................................................................ 9

1.5 Environmental science: ......................................................................................................... 10

1.6 Environmental engineering: .................................................................................................. 10

1.7 Environmental studies: ......................................................................................................... 10

1.8 Man and Environment Relationship: .................................................................................... 10

1.9 Environmental degradation .................................................................................................. 11

1.10 Impact of technology on environment ................................................................................. 12

1.11 Environmental education: ..................................................................................................... 12

1.11.1 Importance of environmental education: ..................................................................... 12

1.11.2 Objectives of Environmental education ........................................................................ 12

Principles of environmental education: ......................................................................... 12

2 CHAPTER: 2 ECOLOGY AND ECOSYSTEM ...................................................................................... 13

2.1 Division of ecology: ............................................................................................................... 13

2.2 Understanding the concepts of the ecosystems ................................................................... 13

2.3 Ecosystems: ........................................................................................................................... 13

2.3.1 The structural component of ecosystems: .................................................................... 14

2.4 Ecosystem model: ................................................................................................................. 15

2.4.1 Food chain: ..................................................................................................................... 15

2.4.2 Food web: ...................................................................................................................... 15

2.5 Biogeochemical cycle: ........................................................................................................... 15

2.5.1 Hydrological cycle: ......................................................................................................... 16

2.5.2 Carbon cycle: .................................................................................................................. 17


3

2.5.3 Nitrogen cycle: ............................................................................................................... 19

2.5.4 Oxygen cycle: ................................................................................................................. 20

2.5.5 Sulfur cycle: .................................................................................................................... 20

2.6 Ecological pyramids: .............................................................................................................. 21

2.6.1 Pyramid of numbers: ..................................................................................................... 22

2.6.2 Pyramid of biomass:....................................................................................................... 23

2.6.3 Pyramids of energy: ....................................................................................................... 23

2.7 Different ecosystems: ........................................................................................................... 23

2.7.1 Marine ecosystems: ....................................................................................................... 23

2.8 Types of ecosystem ............................................................................................................... 24

2.8.1 Estuarine ecosystems: ................................................................................................... 24

Desert ecosystems: ........................................................................................................ 25

3 CHAPTER: 3 RENEWABLE & NON-RENEWABLE RESOURCES ........................................................ 27

3.1 Natural resources .................................................................................................................. 27

3.2 Importance of natural resources .......................................................................................... 27

3.3 Classification of natural resources ........................................................................................ 27

3.4 Destruction of natural resources .......................................................................................... 28

3.5 Conservation of natural resources ........................................................................................ 28

4 CHAPTER: 4 WATER RESOURCES .................................................................................................. 29

4.1 Intuoduction .......................................................................................................................... 29

4.2 Indian scenario: ..................................................................................................................... 29

4.3 Sources of water.................................................................................................................... 29

4.3.1 Surface water source ..................................................................................................... 29

4.3.2 Ground water source ..................................................................................................... 30

4.4 Use of water .......................................................................................................................... 30

4.5 Overuse of water ................................................................................................................... 31

4.6 Problems due to over exploitation of water resources ........................................................ 32

5 CHAPTER: 5 FOREST RESOURCES .................................................................................................. 33

5.1 Introduction........................................................................................................................... 33

5.2 Indian scenario ...................................................................................................................... 33

5.3 Importance of forests ............................................................................................................ 33

5.4 Use of forest product ............................................................................................................ 35

5.5 Deforestations ....................................................................................................................... 35


4

5.6 Effects of deforestation ......................................................................................................... 37

5.7 Afforestation ......................................................................................................................... 38

5.8 Forest degradation in india ................................................................................................... 38

CHAPTER: 6 FOOD AND LAND RESOURCES .......................................................................................... 40

6.1 Introduction........................................................................................................................... 40

6.2 Sources of food ..................................................................................................................... 40

6.3 Undernourishment ................................................................................................................ 40

6.4 Malnutrition or Malnourishment .......................................................................................... 41

6.5 Steps to improve food production: ....................................................................................... 41

6.5.1 Limits of increasing food productton............................................................................. 42

6.6 Environmental impacts of agriculture:.................................................................................. 43

6.7 Impacts of Traditional Agriculture on Environment ............................................................. 43

6.8 Impacts of Modern Agriculture on Environment .................................................................. 43

Problem related to pesticides ........................................................................................ 44

6.8.2 Salinity problem: ............................................................................................................ 45

6.9 Land resources ...................................................................................................................... 45

7 CHAPTER: 7 HUMAN POPULATIONS AND ENVIRONMENT .......................................................... 47

7.1 Important terms: ................................................................................................................... 47

7.2 Habitation patterns and factors governing human settlement: ........................................... 47

7.3 Over population (Population pollution) ................................................................................ 48

7.4 Population growth: ............................................................................................................... 49

7.4.1 Malthusian theory .......................................................................................................... 50

7.5 Population explosion: ............................................................................................................ 50

7.5.1 Demographic transition or Demographic Transition Theory ......................................... 51

7.6 Control of Population Growth: .............................................................................................. 52

7.7 Urban population Growth: .................................................................................................... 53

8 CHAPTER: 8 WATER POLLUTION................................................................................................... 55

8.1 Introduction........................................................................................................................... 55

8.2 Water pollution ..................................................................................................................... 55

8.2.1 Signs of polluted water .................................................................................................. 55

Potable water ................................................................................................................. 56

8.3 Types of water ....................................................................................................................... 56

8.4 Water quality standards ........................................................................................................ 56


5

8.4.1 Water quality parameter: .............................................................................................. 57

8.5 Sources of Water Pollution ................................................................................................... 58

8.6 Classification of Water Pollutants ......................................................................................... 59

8.6.1 Organic pollutants: ......................................................................................................... 59

8.6.2 Pathogens ...................................................................................................................... 59

8.6.3 Nitrogen and phosphorus compounds (Nutrients) ....................................................... 59

Suspended matter .......................................................................................................... 60

8.6.5 Thermal discharge .......................................................................................................... 60

8.6.6 Eutrophication ............................................................................................................... 61

8.7 Control of water pollution ..................................................................................................... 63

8.8 Marine pollution:................................................................................................................... 64

8.8.1 Causes or sources of Marine Pollution .......................................................................... 64

8.8.2 Effects of marine pollution: ........................................................................................... 65

8.8.3 Control of Marine pollution: .......................................................................................... 65

9 CHAPTER: 9 AIR POLLUTION ......................................................................................................... 66

9.1 Definition ............................................................................................................................... 66

9.2 Composition of Air ................................................................................................................ 66

9.2.1 Structure of Atmosphere ............................................................................................... 66

9.3 Sources of Air Pollution ......................................................................................................... 68

9.3.1 (a) Point or Stationary sources: ..................................................................................... 69

9.3.2 (b) Line or mobile sources: ............................................................................................ 69

9.3.3 (c) Area sources: ............................................................................................................ 69

9.4 Classification of Air pollutants............................................................................................... 69

9.5 Air pollutants – Sources and Effects: .................................................................................... 70

9.6 Effects of Air Pollution on Human Health: ............................................................................ 75

9.6.1 Effects of Air Pollution on plants and vegetation: ......................................................... 76

9.6.2 Effects of Air Pollution on Property/Material: ............................................................... 76

9.6.3 Effects of Air pollutants on Climate: .............................................................................. 77

9.6.4 Effects of Air pollutants on Aesthetic Beauty: ............................................................... 77

9.6.5 Factor affecting Air Pollutant: ........................................................................................ 77

9.7 Control of Air Pollution: ........................................................................................................ 78

10 CHAPTER: 10 LAND, NOISE AND THERMAL POLLUTION ........................................................... 82

10.1 Land pollution........................................................................................................................ 82


6

10.1.1 Introduction: .................................................................................................................. 82

10.1.2 Lithosphere: ................................................................................................................... 82

10.2 Land pollution........................................................................................................................ 82

10.3 Land use: ............................................................................................................................... 83

10.4 Land Degradation and its causes: ......................................................................................... 83

10.5 Noise pollution: ..................................................................................................................... 86

10.5.1 Unit of Measurement: ................................................................................................... 86

10.5.2 Sources of Noise Pollution ............................................................................................. 87

10.5.3 Noise pollution effects: .................................................................................................. 88

10.6 Thermal pollution .................................................................................................................. 89

10.6.1 Causes or sources of Thermal Pollution ........................................................................ 90

10.6.2 Effects of Thermal Pollution .......................................................................................... 90

10.6.3 Control Measures of Thermal pollution ........................................................................ 91

10.6.4 Role of individual in prevention of pollution ................................................................. 91

11 ENERGY RESOURCES ................................................................................................................. 92

11.1 Conventional energy sources and its problem ..................................................................... 93

11.2 Environmental impacts of a coal based thermal power plant .............................................. 93

11.3 Environmental impacts of nuclear power plant ................................................................... 94

11.4 Non-conventionalenergysource-advantages and disadvantages ......................................... 95

11.4.1 1. Hydropower ............................................................................................................... 96

11.4.2 2. Solar energy ............................................................................................................... 97

11.4.3 3. Wind energy ............................................................................................................... 98

11.4.4 4. Geothermal energy: ................................................................................................... 99

5.tidal energy: .............................................................................................................. 100

11.4.6 6. Biomass energy: ....................................................................................................... 100

11.4.7 7. Hydrogen energy and Fuel cells: .............................................................................. 101

11.5 Problems due to over use of energy resources .................................................................. 102

12 12. GLOBAL ENVIRONMENTAL ISSUE ..................................................................................... 104

12.1 Introduction: ....................................................................................................................... 104

12.2 Acid rain ............................................................................................................................... 104

12.3 Ozone depletion: ................................................................................................................. 106

12.4 Green House Effect and Global Warming: .......................................................................... 107

12.4.1 Impact of Global Warming: .......................................................................................... 109


7

12.5 International step for Mitigation Global Change: ............................................................... 110

13 CHAPTER: 13 ENVIRONMENTAL ACT AND REGULATIONS: ..................................................... 112

13.1 Environment Protection Laws in India: ............................................................................... 112

13.1.1 The Water (Prevention and control of pollution) Act, 1974:....................................... 112

13.1.2 Air (prevention and Control of Pollution) Act, 1981 .................................................... 113

13.1.3 Gujarat pollution control board (gpcb) ........................................................................ 114

13.1.4 Gujarat environmental management institute (gemi): ............................................... 115

13.1.5 Gujarat ecology commission (gec): ............................................................................. 116

13.1.6 Gujarat institute of desert ecology (guide):................................................................. 116

13.1.7 Department of environment and forest gujarat: ........................................................ 116

13.1.8 Gujarat state disaster management authority (gsdma) .............................................. 117

13.1.9 Role of Non Government Organizations In Improving Environmental Awareness: .... 117

13.1.10 Environmental ethics ............................................................................................... 118


8

1 INTRODUCTION TO ENVIRONMENT, ECOLOGY & ECOSYSTEM 1.1 Environment: The word Environment is derived from the French word “Environner” that means to encircle or surround. All the biological and non- biological things surrounding an organism are included in environment. Environment can be defined as: “External surroundings and conditions which directly or indirectly affects the living organisms.” “Environment is sum total of water, air and land, interrelationship among themselves and also with human beings, other living organisms and property.” Environment is usually divided in to two parts: 1. Biotic 2. Abiotic Biotic environment is made up of all living organisms (Plants, animals & microorganisms) including their reactions, interactions and interrelated actions. Abiotic is composed of external physical factors like temperature, humidity, water, soil, minerals, gases etc. it provides both habitation and raw materials for the synthesis of organic food. These biotic components are in a dynamic state i.e. they constantly affect each other and cannot be isolated from each other. Any constituents of the environment which directly or indirectly affects are growth and development of an organism is called environmental or ecological factor. Examples of environmental factors are climatic factor, topographic factor, biotic factors, and fire.

1.2 Ecology: The word ecology is derived from two Greek word “oikos” meaning house, habitation or place of living and “logos” meaning study. Ecology is the study of the interrelationship between living organisms and their physical and biological environment.

1.3 Ecosystem: Ecosystem is made up two words “eco” and “system” eco means environment and system means an interacting and interdependent complex. The organisms of any community besides interacting among themselves always have functional relationship with the environment. This structural and functional system of communities and environment is called ecological system or ecosystem. It is a community of interdependent organisms together with the environment.

1.4 Components of Environment: Environment can be divided in to four components ATMOSPHERE, HYDROSPHERE, LITHOSPHERE, and BIOSPHERE

1.4.1 Atmosphere: -

Atmosphere is the mixture of various gases and water vapor and subatomic particles that entirely covers the earth extending outward several thousand kilometers. The major gases in a pollution free dry air are nitrogen 78%, oxygen 21%, argon 1%, and carbon dioxide. The minor gases include Neon, Helium, Methane, Hydrogen, Carbon monoxide, Ozone etc.

1.4.1.1 Structure of atmosphere: -


9

On the basis of temperature profile and other related phenomena, atmosphere is divided in to five major layers.

1.4.1.1.1 Troposphere:

Troposphere is the lower portion of the atmosphere which extends up to 8 Km at the poles and 16 Km at the equator on an average it extend up to 10-11 km of the earth surface. The temperature in this region decrease at the rate of 5-7 c/km there are strong vertical air movements in this region which are responsible for the rapid and complete mixing.

1.4.1.1.2 Stratosphere:

It is above troposphere and extends up to 50-55 km up to about 20 Km temperature remains constant then increases with increase in height. Ozone layer is in this layer.

1.4.1.1.3 Mesosphere:

It is the layer above stratosphere and extends up to 80 km. here temperature decreases slowly with altitude but then sharply to about -75 °C.

1.4.1.1.4 Thermosphere:

Temperature increases rapidly with increase in height. The heating of this layer is due to absorption of the solar energy within the thermosphere there is a layer of charged particles known as ionosphere.

1.4.2 Hydrosphere:

The hydrosphere is in fact the water environment. About 70% of earth is covered by water. Water is available in seas, oceans, lake, river, glaciers etc. It is estimated that the hydrosphere contains about 1360 million cubic km of water out of which 97% is in the oceans and sea, 2% in glaciers and ice caps while remaining 1% of fresh water is available for human consumption. Water is main constituent in all the living organism and acts as an important resource for human life.

1.4.3 Lithosphere:

The outer soil crust of the earth is lithosphere. The living organisms, plant and vegetation are supported by the lithosphere.It also contains resources like minerals, organic as well inorganic matter and to some extent air and water. Lithosphere plays an important role as is not only produces food for human beings and animals, but also the decomposition of organic wastes is carried out by a host of microorganisms in the soil.

1.4.4 Biosphere:

Biosphere is the thin outer crust of the earth which included all the living organisms and their environment. It extends from the lowest sea bed level to about 24 km of the atmosphere. Thus biosphere consists of lithosphere, atmosphere and hydrosphere.The living organisms interact with one another in biosphere and sustain their life. The life supporting resources are also available from the biosphere. The waste products in gaseous, liquid and solid waste forms are discharge into biosphere.


10

Though the sustaining and assimilative capacity of the biosphere is tremendous but it is not infinite.

1.5 Environmental science: Environmental science in its broadest sense encompasses all the fields of natural science. It is interdisciplinary. The study by environment scientists has been focused on the natural environment i.e. the atmosphere, the land, the water, and the inhabitants as differentiated from the build environment. Natural science- includes such diverse disciplines as biology, chemistry, geology, physics and environmental science.

1.6 Environmental engineering: Engineering is the profession that applies science and mathematics to make the properties of matter and sources of energy useful in structures, machine, products, systems and processes. Environmental engineering can be defined as application of engineering principles, under constrains to the protection and enhancement of the quality of the environment, public health and public welfare. For examples environmental engineer, plans, designs, constructs, and operate sewage treatment plant, industrial effluent treatment plant, water treatment plant, air pollution control equipments etc...

1.7 Environmental studies:

Refers to the study of basic principles & concepts of natural sciences and application thereof understand multidisciplinary and complex nature of environment and its related problems.

1.8 Man and Environment Relationship: The two words Man and environment are not new to the human history and the interrelation between them is well established. Thinking about the environment is as old as our first human ancestors. Their survival depended on knowledge of it. Concern for the environment is also not new. Since ancient times, people have known the importance of preserving it. Worshipping of trees and rivers, animals and the birds was not based on the superstition; but there was a hidden message preserving and protecting of the environment. The religious rituals served an important purpose- they made people aware of the environment and its important and so indirectly helped preserve and nourishes it. Religion is used largely to ensure community participation in all those practices that would lead to the maintenance of ecological balance. Man is the only living organism capable of modifying its surrounding environment according to the need. Other animals change according to the environment. First man starting hunting the animals and cutting trees for his basics need gradually with the time he started cultivating food grains for that he started hunting animals and cutting trees for his basics needs, gradually with time he started cutting forests and converting them in to grass lands/agricultural fields. To increase his comforts he started disturbing each and every component of the environment.With the start of the industrial revolution the total scenario changed. Everything changed, the use fossil fuel for generation of power for running vehicles, many industries were started to produce


11

the product which increase in pollution all type. Quantity of carbon dioxide emission increased tremendously which has started showing effect in the form of discharge of industrial waste and sewage. Major environmental issues arising due to human activities are global warming, acid rain, ozone depletion and population explosion.

Emission of co2 and the other gases in atmosphere from fossil fuel burning and other human

activities may raise the temperature of the earth’s lower atmosphere several degrees by 2050. This would disrupt food production and flooding of low-lying coastal cities and croplands. An estimated 36500 spices of plants and animals become extinct each year, mostly because of human activities. The main factors which affect the distribution of population and human settlement are: Relief of land, climate, soils, mineral deposits, water supply...

1.9 Environmental degradation

Over the centuries we, Indians, have worshiped nature. We have lived in harmony with nature. However, of late, we have followed western countries past of conflict with nature. The result is that today, we observe and experience, over all environmental degradation. Any objective view of state of environment, of India or any developing countries would clearly show that: Soils are eroding. Forests retreat. Water quality is unsatisfactory. Urban air quality is worse. Watersheds are losing storage capacity. Reservoirs are filled up with sediments. Wildlife and their habitats are being eliminated. Solids wastes pile up and smolder. Costal spawning grounds disappear. Some of these components have changed to such an extent that cannot be set right by self-regulatory mechanism of the environment. Consequently, the changed environmental conditions adversely affect the living organisms of the biosphere. Environmental degradation thus can be defined as the lowering of environmental qualities due to the damaged caused by both natural events and human activities in the basic structure of environmental quantities due to the damaged caused by both natural events and human activities in the basic structure of the environment at local, regional and global levels adversely affecting all living organism including man. The total environmental degradation and pollution arises mainly due to consumption of natural resources by over population of the developing counties and wasteful over consumption of recourses by developed countries. The impact on environment due to increasing population, even developing technologies and the over use of natural resources and capabilities can be easily understood and demonstrated through the IPAT equation popularly known as the impact equation as presented . Environmental degradation has led to the destruction of the environmental stability and ecological balance. Some of the natural events that cause environmental degradation are volcanic eruption, forests fires, earthquakes, floods. Examples of human activities causing pollution and degradation of environment are nuclear explosion, deliberate forests fire, release of toxic gases from automobiles, power plants and various industries etc.


12

1.10 Impact of technology on environment

The technology is developed and used for the human well-being. The intelligent application of technology results in human well-being but not without causing environmental disruptions which undermines the well-being. Technology has played a major role in the well-being of humans but it has some negatives as well. The scale and the rapidly with which technology is being developed and used make all the difference. No technology can be completely free of environmental impacts. This statement simply says that the development and use any technology leads to environmental costs exceeding its benefits. The direct effects include accidents, release of pollutants affecting human health, exhaustion of resources, changes in landscapes, etc. The indirect effects interfere with the vital services supplied to humanity by natural ecological systems .e.g. control of pollution through natural process.

1.11 Environmental education: Environmental Education is an integral process, which deals with man’s interrelationship with his natural and manmade surroundings, including the relation of population growth, pollution, resource allocation and depletion, conservation technology, urban and rural planning to the total human environment. Environmental Education is a study of the factors influencing ecosystem, mental and physical health, living and working conditions, decaying cities and population pressure

1.11.1 Importance of environmental education: The objective of environmental education is to make public aware about environmental problem, and importance of environment protection. It gives us the basic understanding about various aspects of environment and its associated problem.It teaches us the concept of sustainable development.It gives an idea about beneficial use of natural resources without damaging it much. It teaches us how to conserve energy and save our planet. It develops skills to identify environmental problems and their solution.

1.11.2 Objectives of Environmental education Increase awareness of total environment. Increase the knowledge of environment. Improve attitude towards environment. Provide motivation for environmental protection.

Principles of environmental education: Environmental education considers environment in totality.It is not a one short learning process but it requires a holistic approach as it multidisciplinary in nature. Environmental hazards are controllable and every citizen has a moral obligation and responsibility towards this. Education must be given to all section of the society. Help learner to discover the systems and causes of environmental problems.


13

2 CHAPTER: 2 ECOLOGY AND ECOSYSTEM

2.1 Division of ecology: There are two important division of Ecology namely Autecology Synecology Autecology or spices Ecology is the study of individuals spices, their behavior and adaption (adjust-to be suitable for anew use or condition) to the environmental conditions Synecology or community Ecology refers to the study of different communities (group of organisms that are associated to gather as a unit) their composition, their behavior and relation to the environment. E.g. study of a tree in forests.

2.2 Understanding the concepts of the ecosystems

It is useful think of the environment as consisting of four sphere namely i) the biosphere ii) the atmosphere iii) the hydrosphere iv) the lithosphere shows that the fig biosphere (living things-all life on earth ) depends on and interacts with the atmosphere (air), the hydrosphere(water) and the lithosphere(soils and rocks).

Indeed, living organisms cannot be isolated (separated) from their non-living environment as they get material and energy from it for their survival. This brings us to the concept of an Ecosystem i.e. there is continuous interaction between biotic community and its physical environment to produce a natural unit known as an ecosystems.

2.3 Ecosystems: Everything in the natural world is connected. An ecosystems is a natural unit consisting of biotic (living factors) and a biotic (non-living physical) factors. All living and non living factors work together and are dependent on each other in an area, ecosystems are the functional units which results from the interactions of biotic and a biotic components.

Some of the important characteristic is:

Ecosystems have no particular size;

Ecosystem can change with time.

It is a system where matter and energy flows.

It is a system where biotic and a biotic factors work together.

Ecosystems can be natural and artificial.

All ecosystem in nature work the same way.

The foundation on which ecosystems rests the production of the organic matter by photosynthesis. All ecosystems are open systems in the sense that energy and matter are transferred in and out.

The components of the ecosystems:

An ecosystems comprises of two basic components namely

The structural components

The functional components


14

2.3.1 The structural component of ecosystems:

The biotic and abiotic parts, of an ecosystem are known as structural components of ecosystems. The examples of each are given at table

Article I.

Abiotic component:

The major abiotic parts of an ecosystem typically include soil, atmosphere, solar energy, (heat and light of the sun) and water. Each of this play an important role in maintaining the balance in the ecosystem as discussed here under:

The soil: soil is a critical part of an ecosystem. It provides important nutrients and anchors the plants it absorbs and holds the water for plants and animals and is home for numerous (many) living organisms.

The atmosphere: it provides water, oxygen, and co2 for plants and animals in an ecosystem.

The solar energy: the heat and light from the sun i.e. solar energy plays an important role in ecosystems. While heat contributes to the hydrological cycle and warmth, light is crucial for photosynthesis.

The water: without water there would be no life. In addition to being an important part of cells, water is also used by plants to carry and distribute the nutrients they need to survive.

The Biotic component:

The biotic component comprising of living organisms in an organisms in an ecosystem can be divided in to three categories such as: PRODUCERS, CONSUMERS, and DECOMPOSERS These are the functional groups of ecosystems and are known as tropic categories. Together, these groups produce food, pass it along food chain and return the end product is starting materials to the abiotic component of the ecosystem. Producers: Most producers are green plants and algae, which directly most

Producers are green plants and algae, which directly utilize light energy to convert co2 and water to

simplest carbohydrates called glucose and release oxygen as a byproduct. This process is called photosynthesis. The producers produce the complex module from glucose and mineral nutrients such as nitrogen, phosphors, potassium and sulfur which are absorbed from the soil or water. Such complex molecules are essential to sustain the life. Hence, producers are also known as autotrophic organisms. Consumers: organisms feeding on producers are consumers. Consumers are Heterotrophic organisms which include microscopic bacteria to blue whales. The subgroups of consumers are herbivores, carnivores, omnivores. Decomposers: non-photosynthetic bacteria and fungi including mushrooms are decomposers that carry out decomposition. Decomposition is a process of breaking down dead organic matter, including the animal waste into stable end products. Detritivores: Detritivores are organisms that feed on the decomposing particles of organic matter, earthworms and some beetles, termites and maggots are all terrestrial detritivores.


15

2.4 Ecosystem model:

All living organisms need nutrients and energy .basic source of energy is solar radiation, wind and water falls. Energy reaches earth surface and about 15 percent solar energy is utilized in photo synthesis. Plants obtain food from carbon dioxide of atmosphere by by process of photosynthesis at every stage of tropic level there is a loss of energy. About 47 percent of solar energy reaches the earth’s surface however the nutrients have cyclic movement.

Two laws of thermodynamics:

First law of conservation of energy: Energy is neither created nor destroyed. It just changes the forms.

Second law of thermodynamics: when energy is transformed from one to another form there is increase in entropy and decrease in amount of useful energy.

Ecosystem depends on surrounding ecosystem. All small ecosystems are mutually interconnected. The changes in one ecosystem will influence other ecosystem. More ecosystems occur in space and exist in time. Ecosystems have dimensions. Ecosystem are time dependent having pasts, present and future. The functional component of ecosystem comprise of: Food chain Food web Biogeochemical cycle

2.4.1 Food chain:

The sequence of food utilization starting with biomass produce by photosynthetic producers is called the food chain. In a food chain each organisms eats smaller organism and is eaten by the larger one. At the base of the chain there are always green plants or other autotrophic (the producers or first tropic level)

2.4.2 Food web:

An ecosystem consists of many food chains which are interconnected. The food web is complex network of interconnected food chains (each starting from the same point) as shown in

The detritus food chain: The detritus means dead organic matter. The detritus food chain starts from dead organic matter which is eaten by other organisms feeding on them detritivores.

In fact, such food chains are less dependent upon the direct solar energy and mainly depend on the supply of organic matter produced in the ecosystems.

For examples woodlouse is depended on the dead leaves and woodlouse is eaten by a blackbird.

2.5 Biogeochemical cycle:

All organisms are made up of basic elements such as carbon, nitrogen, phosphorus, sulfur, oxygen and hydrogen. These elements are continuously cycled between air, water, soil, rock and living organisms. I.e. the four spheres (atmosphere, biosphere, hydrosphere, and lithosphere) biogeochemical cycles (life-earth- chemical cycle) are the pathways describing the movement of


16

these basic elements through the four spheres of the environment. These cycles driven directly or indirectly by incoming solar energy and gravity are:

Hydrological cycle

Oxygen cycle

Carbon cycle

Phosphorus cycle

Sulfur cycle

Nitrogen cycle

2.5.1 Hydrological cycle:

The solar energy evaporates water from the earth’s surface in to the atmosphere. Some of this water returns to the Earth as rain or snow.

Passes through the living organisms, flows in to the water body and eventually (finally) is evaporate again to continue to the cycle.

This constants motion of water is known as hydrological cycles. The hydrological cycle , showing the transfer of water from the oceans again shown in figure

Evaporation: The conservation of liquid water from oceans, lakes, streams and other bodies of water to water vapor. Transpiration: the process by which the water is evaporated from the plants leave after it has been extracted from the soil by roots. The hydrologist use the term evop-transpiration to described the combine water due to evaporation and transpiration from the plants leaves. Precipitation: it is the process by which water is returned from the atmosphere back to the earth. The water can fall as rain hail, snow, slit. However, the most common form ( the temperate climate) is rain Infiltration and percolation: it is the vertical moment of the water through the soil and permeable rocks to ground water storage area called aquifers. Runoff: it is the water that flow over the surface of Earth, after falling, to the streams, rivers and oceans to resume the cycle.

The hydrologic cycle differs from most other nutrients cycles. In this most of the water remains chemically unchanged and is transformed from one physical state to another. About 84% of water remains vapor in the atmosphere comes from the oceans and the rests comes from the land. Through the hydrological cycle can be viewed as cycle can be viewed as a cycle of renewal of water quality.


17

2.5.2 Carbon cycle:

Carbon cycle is a building block of all organic substance and is the most important for the existence.

It is one of the primary elements forming human tissues and is essential for plants as well. The carbon is found on planet in the following major forms.

As organic molecules in living and dead organisms.

As carbon dioxide in the atmosphere.

As organic matter in the soils. As fossil fuel and sedimentary rocks deposit such as a lime stone, dolomite, chalk, etc. In the oceans have dissolved atmospheric carbon dioxide and calcium carbonate shells in a marine organism The carbon is circulated through the biosphere by the carbon cycle shown in figure. Trace the flows and paths in figure. The carbon cycle is based on carbon dioxide gas, which makes about 0.038% of the volume of the troposphere is also dissolved in water. The activity such as aerobic respiration of the living organisms, volcanic eruption, the weathering of carbonate rocks and the burning of carbon containing compounds release carbon dioxide to the atmosphere.

Photosynthesis is the major driving force for the carbon cycle shown in figure. The terrestrial and aquatic life remove carbon dioxide from troposphere to convert in to glucose and other complex


18

organic compounds and convert to carbon back to carbon dioxide Thus photosynthesis and aerobic respiration circulates carbon in the biosphere representing major part of the global carbon cycle.

The oceans is the major sink of carbon, much of which is found in the form of dissolved carbon dioxide gas, and bicarbonate ions. Approximately 85% of world’s carbon is found in the oceans.

Some carbon takes a long time to recycle, over million of the years for examples. Carbon tied up the fossil fuel, shells & lime stone. Such carbon is released only when fossil fuel are extracted and burned and geological disturbance such as earthquakes, may also release carbon.


19

2.5.3 Nitrogen cycle:

Nitrogen in its gaseous form (N2) constitutes 78% of the volume of the atmosphere (troposphere).

Nitrogen is crucial component of proteins, many vitamins and nucleic acids DNA and RNA. However, it cannot be used directly as a nutrient by most form of life (multi cellular plants and animals).

Nitrogen gas is converted into the usable from by two natural processes as shown in figure. Trace the flows and paths in this diagram.

Nitrogen is cycled via three process namely (I) Nitrogen fixation (ii) Ammonification (iii) Denitrification Nitrogen fixation: The process known as biological nitrogen fixation is carried out by certain type of bacteria in aquatic system, in the soil and in the roots of some plants. The gaseous

nitrogen is biological converted to the ammonia (NH3) which can be used by plants. The

Excess ammonia undergoes ‘nitrification’ where it is converted by specialized aerobic bacteria to

‘nitrate (NO2) ions’ which are easily used by plants as a nutrient. Plants assimilate ammonia,

ammonium (NH4) and nitrate (NO3) ions to produce nitrogen containing organic molecules such as

DNA, amino acids and proteins. Animals get their nitrogen by eating plants.

Fixation also occurs due to lightening where N2 and O2 are converted to the nitrogen oxide.

Ammonification: The nitrogen rich organic compounds are returned in the form of wastes and dead bodies. Specialized bacteria convert this detritus into simpler nitrogen containing inorganic compounds such as ammonia and ammonium ions. This process is known as ammonification.

Denitrification: Ultimately, nitrogen leaves the soil through a process called ‘Denitrification’.

The denitrifying bacteria convert ammonia and NH4+ ions back into nitrogen gas and nitrous oxide (N2O) gas. These gases enter into the atmosphere to begin the cycle again.


20

2.5.4 Oxygen cycle:

Almost all living things need oxygen. They use this oxygen during the process of creating energy in living cells. Oxygen cycle is shown in figure.

Just as water moves from the sky to the earth and back in the hydrologic cycle, oxygen is also cycled through the environment. Plants mark the beginning of the cycle. Plants are able to use the energy of sunlight to convert carbon dioxide and water into carbohydrates and oxygen in a process called photosynthesis. This means that plants breathe in carbon dioxide and breathe out oxygen. Animals from the other half of the oxygen cycle. They breathe in oxygen which is used to break down carbohydrates in to energy in a process called ‘respiration’

Carbon dioxide produced during respiration is breathed out by animals into the air. So oxygen is created in plants and used up by animals, as is shown in figure during the day time plants use some oxygen to break down the carbohydrates, just as animals do. During night time they.

Absorb oxygen from atmosphere for respiration and give of carbon dioxide. Just as animals do. This oxygen is cycled in the atmosphere through the process of photosynthesis and respiration very large surface area.

Even through plants produce approximately ten times as much oxygen during the day as they consume at night, the night-time consumption of oxygen by plants can create low oxygen conditions in some water habitants.

Oxygen in water is cycled through the process of (i) Dissolution from air & (ii) consumption of organisms, for respiration and oxidation of organic substances.

2.5.5 Sulfur cycle:

Sulphur is an essential constitute of certain amino acids and vitamins of the B-complex group. So plants and animals depend on a continuous supply of sulphur. It is present in the atmosphere as

hydrogen sulphide (H2S) and sulphur dioxide (SO2) gas.


21

In, nature, these gases are emitted at an alarming rate. In soil, sulphur is present as a sulphide sulphate and organic sulphur. It is taken by the plants and through the food chain it returns to the soil. Fungi like aspergillums and neurospora decompose the sulphur from

proteins as sulphate by aerobic decomposition. These sulphates undergo further cyclization. In the aerobic conditions, H2S is produced from the decomposition of the proteins by E.coli.

These days while industrialization and rapid urban development has increased the concentration in the atmosphere where it reacts with the moisture and causes acid rain. As a result, soil and aquatic environment become more acidic and detrimental to organisms the sulphur cycles shown in the figure.

2.6 Ecological pyramids:

In 1927, scientist Charles Elton observed that the numbers of animals present at the top of the tropical level is much less compared to the number of animals present at the base of the food chain. He also plotted his findings on a graph to get a pyramid like structure.

He called this pyramid the Estonian pyramid after his name. It is also known as the ecological pyramid. Thus, an ecological pyramid is the graphical representation of the tropical structure (the position of organisms in the food chain) and function at successive tropical levels make tiers, with the top carnivores forming the apex. These ecological pyramids are of three types:

Pyramid of numbers

Pyramid of biomass

Pyramid of energy


22

2.6.1 Pyramid of numbers:

This pyramid deals with the relationship between the number of primary producers and consumers of different orders. Depending on the nature of the food chain, in the present ecosystem the pyramids of numbers may be upright or inverted. For examples, in a grassland ecosystem, the numbers of grasses is always high followed by primary consumers that are less, the secondary consumers that are lesser and finally the top carnivore, in this case hawks, which are the least in number. So the pyramid is up right in this case shown in fig.

HAWK

SNAKE, LIZARD

RABBIT, GRASSHOPPER

GRASSLAND (PRODUCERS)

On the other hand, in forests ecosystems, the producers are big tress on the fruits of which birds and other primary herbivores depend. Thus, the number of primary consumers is always greater than the numbers of the producers. Again the numbers of the secondary consumers is less then primary consumers and obviously the number of top carnivores is the least. thus, the shape of the pyramid looks as shown in fig.

HAWK

SNAKES

BIRDS AND MONKEYS

TREES

In case of a parasitic food chain the pyramids are always inverted. This is because a single plant supports large number of herbivores. These in turn, support a large number of parasites. Thus, the ecological pyramid, in this case, is always inverted as shown in fig.


23

As it is very difficult to count the exact number of all organisms, the pyramid of numbers cannot give true picture of the tropic structure for an ecosystem. They generally vary with different communities having different types of food 77 chains in the same ecosystem.

2.6.2 Pyramid of biomass:

In this concept, the individual in each tropical level is weighed instead of being counted. Thus, in the pyramid of biomass the total weight of each tropical level is represented. For most of the ecosystems on land, the biomass of producers is large and it gradually decrease with each successive layer resulting in an upright pyramid as shown in

2.6.3 Pyramids of energy:

The pyramids of energy of energy actually depicts the rate at which the food mass is passed through the food chain. It’s passed based on the actual amount of energy that individuals take in how much is burnt up in metabolism, how much remains in the waste products and how much they store in the body tissue; this is a reflection of the law of the thermodynamics. Thus, the energy pyramid gives the best picture of the overall nature of the ecosystem. The actual amount of energy content in successive tropical level from the producers to various consumers decreases. Hence, the shape of energy pyramid is always upright.

For, examples a forest ecosystem receives 1000 calories of sunlight in a day of which about 100 calories are stored in the plant , When any herbivores eats the plant, it receive 100 calories. But after its expenditures, its own metabolism lets its store 10 calories of energy. Thus, any carnivore eating the above herbivore receives 10 calories. It can store one calories of energy after its expenditure for metabolism. Thus, energy pyramid looks as in figure

2.7 Different ecosystems:

Ecosystem can be defined as the structural and functional unit of ecology. Our earth is giant ecosystem where abiotic and biotic component are constantly interacting with each other bringing structural and functional changes in it. Due to vastness it is subdivided in to units of smaller ecosystem like:

Terrestrial ecosystem such as forest, grassland, desert

Aquatic ecosystem such as fresh water, marine water. This unit ecosystem is open system with no constraint with boundaries and with constant interaction between biotic and abiotic components.

2.7.1 Marine ecosystems:

Three-Fourth of the earth’s surface is covered by the oceans with an average salinity of 35 parts per thousand. The concentration of nutrients in the marine ecosystem is low. However marine


24

ecosystem can be divided into littoral, neritic, pelagic and benthic zones. The shoreline between the land and the open sea is termed as a littoral zone. Waves and tides have the maximum effect in this zone. In the rocky shore region, organisms such as star fish and algae are found, where as in the sandy shore area, organisms burrowing and adhering to sand are dominant. in bays, algae are found on the surface of mudflats. Often photosynthetic bacteria are present below the algae.

Just above the continental shelf lies the neritic zone. This zone is rich in nutrients and hence rich in spices too. Sunlight are also penetrates the neritic zone. Hence, the productivity of this zone is high. Phytoplanktons and zooplanktons are abundant and support the fishing grounds; however, pollution affects the zone first.

The open sea constituting 90 percent of the total oceans surface forms the pelage zone. Photosynthesis is carried out by phytoplankton present in this zone. Zooplanktons, shrimps and jelly fish are also found here. However though this zone is very large in area, it is low in nutrients and productivity. Fin and blue whale are found here. An organism of the pelagic zone is present below the light penetration zone and totally depends on rain of a detritus of a upper regions for their nutrition. In deeper water, many animals have poor vision fishes are biome nascent. Some deep-water fishes are light absorbing organ.

The floor of the constituents the benthic zone. It stretches of the edge of continental surface shelf to deepest oceans trenches. Organisms present here are heterotrophic. Rooted animals such as sponges, sea lilies, sea fans so on are present here. While snails and claims remain embedded in the mud, star fish, sea cucumber, and sea urchins move on the surface.

2.8 Types of ecosystem

2.8.1 Estuarine ecosystems:

Costal bays, river mouth and tidal marshes from estuaries. Here fresh water from. The river mixes with the oceans water. The degree of salinity depends upon the amount of freshwater flow and tidal inflow. Estuaries are more productive than adjacent rivers. Rooted plants are supported in shallow water of lesser salinity than the sea.

Organisms present in estuaries are those which are capable of tolerating fluctuation in the salinity water. Some oyster, crabs and sea shrimps are found here. Estuaries contain producers such as sewed, marsh gases, benthic algae and phytoplankton. They are also used as nurseries by deep water fishes to bring up their younger ones.

Grassland ecosystems: continental interiors, especially in temperate regions with low rainfall are dominated by grasses. Grasslands come under the terrestrial ecosystem and occupy about 19 percent of the earth’s total surface. The abiotic factors and biotic components of a grassland ecosystem are described as follows: Abiotic component;- The nutrients of the environment, such as C, H, O, N, P ,S, and so on are supplied by carbon dioxide, water, nitrates, phosphates and sulphates , present in the air and soil area.


25

Biotic component:- The biotic component consists of the following:

Producers: these are mainly grasses, a few forbs and shrubs that contribute to a primary production.

Consumers:

Primary consumers: Herbivores such as bison, cattle and rodents feed on grasses and insects such as some termites and millipedes feed on leaves of grasses.

Secondary consumers: These are carnivores such as foxes, jackals, snakes, frogs, lizard, and dogs that feed on herbivores, the primary consumers.

Tertiary consumers: Birds such as hawks feed on secondary consumers in grassland ecosystems.

Decomposers: Microbes, some bacteria, actinomycetes and fungi such as mucor, aspergillus, penicillium and rhizopus become active in the decay of dead organic matter and bring back the minerals to the soil. This soil is rich in mineral contain and useful for farming.

Desert ecosystems:

Continental interiors with very low sporadic rainfall and with a low humidity are converted to deserts. The sun’s rays easily penetrate the atmosphere making the ground temperature very high during the day. The nights are very cold. The spices composition is quite varied because of the extreme climatic condition.

BIOTIC COMPONENT: The biotic component consists of the following.

Producers: Drought resistance vegetation like euphrobias, sage bush, and cacti are the common here. Lower plants such as lichens and xerophytic mosses may also thrive in oasis area.

Consumers: A large numbers of animals, mainly various reptiles and insects are seen here. some birds and camel that feed on shoots of plants are also present here.

Decomposers: A few fungi and thermophillic bacteria are present in the ecosystem as the vegetation is less; the decay is also less and is managed by these decomposers.

Forest Ecosystems:

The forest an ecosystem contains interacting biological communities and faunal communities which together interact with the physical environmental resulting an integrated structure. It is always the vegetation which forms the base of the food chain.

According to the forest survey report of 1993, about 19.5 per cent of the total geographical area of India under the forest covers. Depending on factors such as annual rainfall, its disruption over the year, mean monthly temperature, total annual dry and wet period and


26

relative humidity, the Indian forest can be classified in to 16 different types. However, the different components of all forests ecosystems are the same.

Abiotic Component: All inorganic, organic substances present in the environment and minerals present in the forests constituents the abiotic components. Mainly the amount of the sunlight depends on the stratification conditions of the tress. Biotic components: the biotic component consists of all living components of the environment which constitute producers, consumers and decomposers.

Producers: The vegetation of the forests is the producers. The term vegetation includes big trees medium size bush and small herbaceous plants. all vegetation contain chlorophyll and performs photosynthesis. The herbaceous vegetation contains maximum green photosynthetic tissue produces the maximum and being annual, it is also decomposing very fast. Thus herbaceous vegetation contributes to the nutrient cycling and boots the production in the forests. Consumers are as follows: Primary consumers: Insects like ants, beetles, flies, spiders, birds and other herbivores such as deer, squirrels, and mongoose and elephants graze over the primary producers and convert in to the secondary production. Thus, herbivores are the link between the primary producers and carnivores. Secondary consumers: carnivorous animals such as snakes, birds, fox and jackals which are the predators of the herbivores come under that category. These animals regulate the population size of herbivores and there by their grazing activity. In this way, the base of food chain is maintained. Tertiary consumers: These are top carnivores, such as lions, tigers and hawks that feed on secondary consumers. Thus there exists a complete balance between two different groups of animals and plants and forest ecosystem is naturally conserved. When there is a loss of some balance, the destruction of the forests beings. Decomposers: These organisms remain conformed to the soil of the forests and have the capacity to degrade all dead plants, herbivores and carnivores tissue to release nutrients in to the soil. These nutrients are again used by the producers. A wide variety of the microorganisms such as fungi, bacteria, mites, nematodes, protozoa and earthworms are present in the forests soil to perform the role of decomposers. The rate of decomposition is more rapid in tropical and sub-tropical forests then in a temperature one. Thus, decomposers act as a scavengers of the forests, have links with all group of plants and animals and help in recycling the nutrients.


27

3 CHAPTER: 3 RENEWABLE & NON-RENEWABLE RESOURCES

3.1 Natural resources Any component from natural environment that can be utilized by living organisms for their survival and welfare directly from the natural environment, are called natural resources. These are basically resources gifted by nature to us like, Sunlight, Air, Water, Plant and animals, Soil and minerals, etc

3.2 Importance of natural resources The importance of natural resources can be summarized as follows: All living beings use natural air to breath. All living beings use land for getting shelter. All humans, animals, birds, and other living organisms use water to drink. Natural resources like forests provide timber, food, fresh air, paper, medicines etc. Natural resources like gas, minerals and metals are necessary for economic development of country. Natural resources like coal give energy to us.

3.3 Classification of natural resources

Natural resources

Biotic (living) resources Abiotic (non-living) resources Forest Land Wildlife Water Agriculture etc. Minerals, metals Natural gas, etc Based on availability natural resources are classified as under: Natural resources

Renewable resources Nonrenewable resources

(in exhaustible resources) (exhaustible resources)

Renewable resources Nonrenewable resources

These are the natural resources which can These are the natural resources which do not

generate on their own, through natural generate on their own, or regenerate very

cycles within reasonable time period. slowly.

These are also called in exhaustible These are also calledexhaustible resources.

resources.

For example, For example,


28

Sunlight, Air, Water, Plant and animals, Fossil fuels such as coal, petroleum, natural

birds, soil, wind, rainfall, tidal and gas, metals, minerals, etc.

hydropower

As per possibility of recycling, Nonrenewable resources may further divided into two types as:

1. Recyclable resources: these are the resources which can be reprocessed after collection to new products. For example, Ores of metals, glass, plastic product, etc

2. Non-recyclable resources: these are the resources which can be reprocessed for recycling or reuse and are lost after giving energy. For example, Fossil fuels (coal, oil, petroleum, natural gas), Uranium, thorium, etc.

Another classification of natural resources is as under: Natural resources

External resources internal resources

Soil, Forest, land, Ground water, fossil fuel,

Surface water, Minerals, metals

Wildlife, sunlight, Natural gas, etc

Agriculture etc

3.4 Destruction of natural resources The word DESTRUCTION OF NATURAL RESOURCES is used to mean that use of natural resources is at an alarming rate and to such extent that is no more available. Some of the causes of destruction are: High population growth causes very high use of natural resources, Unplanned industrialization ,Urban development,

3.5 Conservation of natural resources

Conservation of natural resources means sustainable use of natural resources. Excessive and unplanned use of natural resources has depleted these resources so much that there is urgent need for their conservation. The main objectives of conservation of natural resources are: To preserve the quality of environment. To ensure continuous and balanced cycle of nature


29

4 CHAPTER: 4 WATER RESOURCES

4.1 Intuoduction Water is a vital natural recourse which forms in all the basis of all life. It is the key resources economic in ail activity ranging, form agricultural to industry. With ever increasing pressure of human of there is severe stress on water resources. About 70% of earth surface is covered by water and most of the plants and animals have 60-65% of water in body.

97% of water is in oceans and seas, 2% in glaciers and ice caps while remaining 1% is of fresh water.

Water keeps on cycling endlessly through the environment, which we called “hydrological cycle’’.

The water from various moist surfaces evaporates and fall again the earth in the form of rain or snow and passes through the living organisms and ultimately its returns to atmosphere.

4.2 Indian scenario: In India out of total rain fall in an area of 3290 lakh hectors , a rain fall of 4000 billion cubic meters annually occurs, out of the total ,41% is lost in evaporation, 40% is lost in runoff 10% is retained in soil moisture and 9% seeps in for recharging to the ground water.

4.3 Sources of water

4.3.1 Surface water source Ponds: Natural small sized depression formed within the surface of the earth, which gets filled up with water is known as ponds.

Lakes: A natural large sized depression formed within the surface of earth, when gets filled up with water is called lakes. The quality of water in lakes is generally good and does not need much purification.

Streams: In hilly regions, generally small amount of water runs off towards the earth. This small run offs are known as streams.

Rivers: rivers are born from the hills when numbers of stream combine together. Rivers are the most important sources of water for public water supply.

Perennial river Non perennial river

1. Those in which water is available throughout 1. Those in which water is not available mall

the year the time.

2. Fed by rain during rainy season and snow during 2. Fed by rains during rainy seasons

summer seasons.

3. It is source of public supplies directly 3. The construction of dams is generally

adopted and water is used for irrigation and

hydropower etc.


30

Storage reservoir: These are formed by constructing hydraulic structures like dams across river. That stored water is generally used for irrigation and hydropower.

Stored rain water: At some places, on the terrace of the buildings water is stored during rainy seasons in a big tank and thereafter whenever requirement is there that stored water is used.

4.3.2 Ground water source

Springs: The natural outflow of groundwater at the earth’s surface is said to form spring. A previous layer sandwiched between two impervious layers, give rise to natural spring. It supplies where small amount of water.

Infiltration galleries: Infiltration galleries are horizontal or nearly horizontal tunnels constructed at shallow depth(3 to 5 m) along the banks of the river through the water bearing strata.

Wells: A well is a hole usually vertical, excavated in the earth for bringing ground water to the surface.

Following are the type of well

Dug wells or open wells: open wells are generally open masonry wells, having bigger diameters, and are suitable for low discharge of 1-5 lit/sec. the diameter of open wells generally vary from 2 to 9 m. and generally less than 20 m in depth. The yield of an open well is limited because it can be excavated only to a limited depth where the ground water storage is limited. Tube wells: It is long pipe or a tube. It is bored or drilled deep into the ground, intercepting one or more water bearing stratum. In the tube wells, larger discharges can be obtained by getting a higher velocity as a larger area of the water bearing stratum. Artesian well: When a well is constructed in a previous layer which is bound between two impervious layers, the water comes on the surface with some pressure at which it is stored in the layer. French well or Radial well: It is special type of well in which surface water is collected from the river bed A natural or redial perforated pipes are laid with slope towards the center below the bed level of the river. A well will collect the water at the center and then it is pumped out with the help of a pump.

4.4 Use of water Consumptive use: Most of the water in this type of use of water is utilized or consumed.e.g. Irrigation use: water is used for required for the growth of plants and crops. This water is cyclic. The water will be taken through the root system and surface water is lost as evapo-transpiration losses.

Partial consumptive use: water is partly consumed and part of it is wasted as used water. 60 to 80% of water supplied to home is wasted. Part of waste water can be reused. They include water needs for: Domestic water need: There are number of activities in daily life where water is needed e.g. drinking, bathing, cooking, washing of utensils, clothes, cleansing of house, vehicles etc. The water needs depend on population, living standard and habits of community, season of the year, climate of the palace etc.

1. Fire water need: There are number of formula suggested to calculate water required for

firefighting. Separate provision is required for high rise building. Normally a community with more than 50000 people, a provision is made as per the formula, Q=100√p

3. Institutional water needs: the water requirement for different institute is different depending

upon the type and function of institute.


31

4. Industrial water needs: There are different uses of water in industry. It may be for process use,

like chemical industries need water as solvent. Non process uses like cooling, washing of

machine floors, working staff needs etc. all the demand are added and a sum total is expressed

in terms of a unit related with the product or material. Some industries need huge quantities of

water while some needs little. 5. Water needs for thermal and nuclear power generation: For power production water is

consumed in two forms. Main needs are to produce stream, which in turn is used for turning

turbine to produce electricity. The other water need is for cooling. There will be some

evaporation loss of water in both forms. It is estimated that 200-250 liters of water will be lost

per kilowatt power generation in cooling. Nuclear power station needs 5% more water than

fossils fuel plant. Non consumptive use: There is no direct consumption of water. Sometimes there will be loss of water due to evaporation from the storage at source and point of use. They include:

1. Hydroelectric power production: It will use the energy of stored water to turn a prime mover

to produce electricity. Depending upon the stored water quantities and height of stored water

different types of power station are designed. 2. In land navigation: An irrigation canal or a river can also be used for in land navigation. Water

transport is the cheapest means of transport. 3. Pollution control: Water is used as sink for waste disposal. The water has the capacity to dilute

the waste. It has self-purification capacity. Surface water as well as ground water sources are

used for diluting waste water. There are several process like sedimentation, de-oxygenation, re-

oxygenation, biological degradation etc. are involved in self-purification of a river. There is a

limit beyond which a water body cannot assimilate the waste. Many water bodies of the world

are already loaded heavily by different types of pollutants. 4. Recreational use: The natural water bodies and artificially created waste water are used for this

purpose. Some of the recreational uses may be of contact type, while other may be of non-

contact type. Contact type recreational uses include swimming and bathing. Non-contact uses

include fishing, boating, water sports, sightseeing etc. many water parks and resorts are now

being developed commercially.

4.5 Overuse of water

Water is used by every living organism on the earth. The requirement of everybody varies.

People should utilize it economically, but the situation is different for human beings. Water requirement on the earth is maximum on the earth.

Population growth has created much demand of water. In some areas the demand for water already exceeds nature’s supply, and growing number of countries are expected to face water storage in the future.

Expansion of business activity ranging from industrialization to services such as tourism and entertainment continues to expand rapidly. This expansion requires increased water services


32

including both supply and sanitation, which can lead to more pressure on water resources and natural ecosystems.

Due to expanding human population, competition for water is growing such that many of the world’s major aquifers are becoming depleted. This is due to both direct human consumption as well as agriculture irrigation by ground water.

Due to rapid urbanization, more peoples move towards urban areas which lead to overuse of water in urban areas.

Water disputes between the states are increasing as they have to meet the increase in water demand due to overuse of water.

4.6 Problems due to over exploitation of water resources

Over exploitation is term often used when the rate of extraction exceeds the safe yield of any water resources?

Problems due to over exploitation of surface water:

Decrease in flow of water in streams and rivers.

Drying of lakes and ponds in summer

Water logging

Migration of people

Desertification of soil

Problems related with overuse of ground water:

Drying up of springs and shallow wells

Increased salinity

Increased in pumping cost as the water table lower

Depletion of water in aquifer due to heavy pumping

Decrease in production due to scarcity of irrigation of water


33

5 CHAPTER: 5 FOREST RESOURCES

5.1 Introduction Forest resources play an important role in the economy of any country. It is highly complex, changing environment made up of a living and non-living things. Living things include trees, shrubs, wildlife etc. and non-living things include water, nutrients, rocks, sunlight and air.

Forest very a great deal in composition and density and are distinct from meadows and pastures.

Forest is important to humans and the natural world. For humans, they have many aesthetics, recreational, economic, historical, cultural and religious values. Forest provides fuel, wood, timber, wildlife, habitat, industrial, forest products, climate regulations, medicinal etc.

5.2 Indian scenario

According to the state of forests report 1999, the total forests cover of india is 6,37,293 km2

which is 19.39% of the total geographical area of country. Out of this dense forest is 11.48% open forestis7.76% mangrove forest is 0.15%

Open forests is where the forests cover is not very dense the area is more open. Mainly found in Himalayan region and northern eastern part of India.

Dense forests are an area of forests where the vegetation is very thick and canopy cover is dense. The two main areas are Western Ghats and eastern Himalayas.

Mangroves are short dense trees that tolerate and adopt themselves well to both saline and fresh water and grow in coastal area. The genetic sunder bans are the largest mangroves in India.

Among 16 different types of the most common is tropical dry deciduous, tropical thorn, tropical moist deciduous this three types of tropical deciduous forests account for more than 76.5% forests in India. Nearly 96% of forests are owned by government,2.6% by corporate bodies and rest are private ownership.

5.3 Importance of forests

Ecological Importance or uses of Forests

Regulation of global climate and temperature

Forest play a crucial role in regulation of global climate and temperature as forest cover absorb the solar radiations that would otherwise be reflected back into the atmosphere by bare surface of the earth.

Transpiration of plants increases the atmosphere humidity which affects the rainfall, cools the atmosphere and thus regulates the hydrological cycle.


34

Reduction of Global Warming

The main greenhouse gas co2 is used by forests for photosynthesis process the forest act as

a sink for co2 there by reducing the greenhouse effect due to co2

Production of Oxygen

During Photosynthesis process forest releases oxygen a very important gas for human survival thereby are called as lungs of earth.

Conservation of soil

They prevent soil erosion by binding the soil particles tightly in their roots. They also reduce the velocity of wind & rain which are the main cause of erosion.

Control of water flow

The forest act as a giant sponge they slow down runoff, absorbing and holding water that recharges springs, streams, and ground water.

Habitat to wild life

They provide the habitat for high wild life species diversity than any other biosphere.

Absorption of air pollutants

Forest absorbs many toxic gasses and air pollutants and can help in keeping air pure.

Absorption of noise

cover absorbs the noise and help in preventing noise pollution.

Economical importance of forest

Timber: Wood used for commercial purposes like for making furniture and other items like boats, bridges, railway sleepers and other day to day uses.

Fuel Wood: The wood is used as fuel for cooking and other purposes by poor people.

Raw material for wood based industries: forest provide raw material for various wood based industries like paper and pulp, sports goods, furniture, boat building, manmade fibers, composite wood, match boxes etc.

Food: Fruits, roots, leaves of plants and trees along with the meat of forest animals provide the food to the tribal people.


35

Bamboo: these are used for matting flooring, baskets, ropes, cots etc.

Miscellaneous Products: Miscellaneous products like, resin, gums, oils, medicines, Katha, lac, waxes, honey, insecticides, rubber folder is provided by forests.

5.4 Use of forest product Forests are important to humans and natural world. They are of immense value to the life and prosperity of human beings and of nations. The use of forest products includes: Wood is the major forest product. It is used as fuel wood for cooking and heating. It accounts for almost half of all wood harvested worldwide. About 1.5 billion people depend on fuel wood as their primary energy source. The world consumption of fuel wood is estimated to be more than 1000 million cubic meters. Industrial timber and round wood obtained from forests are used to make lumber, plywood, veneer, board, doors, windows, furniture, carts, ploughs, tool handles, sports goods etc. It is also a raw material for the manufacture of paper, rayon and film. Minor forest products:

(a)It provides resins, thatch, rattan, fruits, nuts, herbs, medicinal plants, pharmaceuticals, oil, forage, commercial flowers, species and syrups.

Bamboos are used in rafters, roofing, walling, flooring, scaffolding, matting, basketry and cart wood and also used as raw material in paper and rayon industry.

Canes are used for making furniture, ropes, walking sticks, umbrella handles and sports goods. Oils obtained from a variety of plants are used in the manufacture cosmetics, soaps, pharmaceuticals tobacco etc.

Several types of tanning materials, dyes, gums and resins obtained from forest plants are utilized in many industries.

Lac, honey, wax and silk are items of economic value obtained from forest insects.

Tendu leaves are used for preparation of bidi.

It provides hundreds of drugs, spices, insecticides and poisons.

It also provides Ritha, Shikakai sola pith and Rudraksha as commercial products.

5.5 Deforestations Deforestations refers to long term or permanent loss of forest cover


36

Land that is permanently converted from forest to agricultural land, golf courses, cattle pasture, homes, lakes or deserts The Food and Agriculture organization of the UN defines tropical deforestation as "Change of forest with depletion of tree crown cover more than 90%". The United Nations conference on Environment and Development in 1992 defines deforestation as "land degradation in arid, semi-arid and sub-humid areas resulting from various factors including climatic variations and human activities. The clearing of forests are economic gains for short term while the lo.ng-term damaging effects of deforestation are disastrous and irreversible.

CAUSES OF DEFORESTATION

Population explosion: Population explosion is the root cause of all the environmental problems, vast area of forests are cleared for human settlement.

Shifting Cultivation: It is a traditional agroforestry system widely practiced in north eastern region of country in which felling and burning of forests followed by cultivation of crop for few years and abandon of cultivation allow forests for re-growth cause extreme damage to forest.

Growing food demand: To meet the food demand of rapidly growing population more and more forests are cleared off for agricultural purpose.

Fire wood: Increasing demand of wood for fuel increases pressure on forests.

Raw material for wood based industry: Increasing demand of wood for making furniture, plywood, match box etc. results into tremendous pressure on forests.

Infrastructure development: Massive destruction of forest occurs for various infrastructure developments like, big dams, highways projects etc.

Forest fires: Forest fires may be natural or manmade cause a huge loss of forest.

Over grazing: Overgrazing of land by cattle result into soil erosion, desertification.

Natural forces: Floods, storms, heavy winds, snow, lightening are some of the natural forces.

Mining activities: mining activities leads to forest clearance results into forest pastures.


37

5.6 Effects of deforestation Deforestation adversely and directly affects and damages the Environment or humans both. The adverse effects of deforestation are discussed below: Soil Erosion: The soil gets washed away with rain water on. Sloppy area in the absence of trees leading to soil erosion.

Expansion of Deserts: Due to action of strong winds laden by fragmented rock dust' denuded land mass gradually gets converted to sand deserts. This effect is more pronounced in rain scarcity areas.

Decrease in rainfall: In the absence of forest, rainfall declines considerably because forests bring rains due to high rate of transpiration. It maintains high humidity in atmosphere.

Loss of Fertile land: Less rainfall results into the loss of fertile land owing to less natural vegetation growth.

Effect on climate: Deforestation induces regional and global climate change' climate has become warmer due to lack of humidity in deforested regions' Also the patterns of Rainfall have changed. Droughts have become common.

Lowering of water Table: Lack of recharging of underground reservoirs, results into a towering of water table.

Economic losses: Deforestation will cause loss of industrial timber and non-timber products and loss of long term productivity on the site.

Loss of flora & fauna: certain species of flora & fauna are extinct form the planet earth.

Loss of Bio-diversity: Loss of flora and fauna has resulted into loss of biodiversity leading to disturbances in ecological balance worldwide.

Loss of medicinal plants: There are many species of plants, which, have been used in India for centuries as insecticide, fungicide, in medicine and in Bio-fertilizers. De-forestation may lead to the extinction of these valuable plants.

Environmental changes: It will lead to increase in carbon Dioxide concentration and other air pollutants. This Warming would result in Global warming.

Change in living habits: This may force indigenous people to live a new life for which they are not prepared. Disturbance in forest ecosystem may result in changes in other ecosystems that may be separated by great distances.


38

5.7 Afforestation The conservation measure against the deforestation is afforestation. The development of forest by planting trees on waste land is called afforestation

The main objective of afforestation

To control the deforestation

To prevent soil erosion

To regulate rainfall and maintain temperature

To control atmospheric condition by keeping it clean

To promote planned uses of wasteland

To protect forest ecosystem and to get benefits of forest products

5.8 Forest degradation in india

At the beginning of 20th

century about 30 % of land in India was covered with forests but by

the end of 20th

century the forest cover was reduced to 19.4%

As a result of exploitation, the tropical forest cover in India, is now only reduced to coastal western Ghats and northern India.

We have a huge population size and a very low precipitate forest area 0.075 Ha per capita as compared to 0.64 ha/ capita of world forest area.

The National forest policy has recommended 33 % forest area for plains and 67 % for hills.

The deforestation rate per unit population in India is lowest among the major tropical countries.

For effective forest management of country we have to take the confidence of tribal that have been livings in forest.

DAMS AND THEIR EFFECTS ON FOREST AND TRIBAL PEOPLE When a dam is constructed across any river a huge artificial lake is developed in the catchment area of that dam. It is also known as back waters. The backwaters covering a large surface area. Create a lot of ill-effects on the living environment. They are as follows:


39

It creates the loss of forest which is submerged under the back waters of the dam.

It creates danger to the habitat of the wild life. The wild life is forced to migrate.

It also affects the land under cultivation, in the catchment area as the crops get submerged under water.

The roads, already in existence are put under water after the construction of dam. So the road network is damaged.

The four major dam projects

Sardarsarovar project, Gujrat

Narmada project, M.P

Bodhghat project on indravati river, M.P

Tehri dam on bhagirathi river, uttrakhand Thousands of hectares of forests will be destroyed for constructing large dams. In saradarsarovar project alone, 245 villages will be submerged in three states, Gujarat, M.P and Maharashtra.


40

CHAPTER: 6 FOOD AND LAND RESOURCES

6.1 Introduction

food is one of the basic requirement of human being, it is the most important material that our body needs for its proper functioning and well-being at all stage of our life human diet is not restricted to any special category of food, of plant and animal origin, as no single food provides us with all the nutrients that we need.

6.2 Sources of food

Although the earth has perhaps 30000 plant species with parts that people can eat, only plants and 8 animal species supply 90% of our food. Our main food resources are

Agricultural crops (rice, wheat, maize, potato, soya bean, millet, sugarcane, barely, oats,

etc.)

Domestic animals (cattle, sheep,goat, etc.)these animals are the sources of milk and meat. Aquaculture (fish and sea food) It is the production of food from aquatic habitants - marine and fresh water. Fish and sea food contribute about 70 million metric tons of high quality proteins to the world's diet.Although aquaculture provides only small amount of the world’s food at present, it is an important source of protein for many countries, especially in Asia and Europe. The FAO estimated that about 840 million people remain chronically hungry, nearly 820 million of them in developing counties. There are generally two kinds of food problems across the world. Undernourishment Malnutrition. Every year 40 million people die of undernourishment and malnutrition.

6.3 Undernourishment It is the lack of sufficient calories in available food, so that one has little or no ability to move or work. The FAO estimates that the average minimum daily caloric intake over the whole world is about 25OO calories per day. People who receive less than 9Oo/o of their minimum dietary intake on a long term basis are considered undernourished.


41

Those who receive less than 80% of their minimum daily caloric intake requirement are considered "seriously undernourished".

Children in this category are likely to suffer from permanently stunted growth and mental retardation. This can be prevented with a better diet, clean water and simple medicines. of The world food summit,1996 has set the target to reduce the number of undernourished to just half by 2O15, which still means that there will be 410 million undernourished people on the earth.

6.4 Malnutrition or Malnourishment Malnourishment is the lake of specific components of food such as proteins, vitamins or essential chemical elements. It is due to nutritional imbalance caused by a lack of specific dietary components or an inability to absorb or utilize essential nutrients. It may occur in both rich and poor countries. e.g. people in richer countries often eat too much meat and fat and too little fiber, vitamins, trace minerals and in poor countries people often lack specific nutrients because they cannot afford expensive food. Utilize essential nutrients. Major problems due to malnutrition. Marasmus: Lack of protein and calories. Kwashiorkor: Lack of protein in the diet which leads to stunted growth in infants and causes failure of neural development and learning disabilities. Anemia: Caused by an inability to absorb iron. Goiter and hypothyroidism: an iodine deficiency in the diet in early childhood can cause abnormalities such as mental retardation and deaf-mustism. Pellagra: Deficiency of tryptophan and lysine vitamins. Chronic hunger: This occurs when people have enough food to stay alive but not enough to lead satisfactory and productive lives.

6.5 Steps to improve food production:

Available land acreage should be properly and judiciously utilized.

Soil fertility should be increased through wide use of fertilizer and organic manures.

Mixed cropping should be practiced wherever possible.

Crop rotation should be done.


42

Soil erosion and loss of nutrients should be prevented by maintaining vegetation cover throughout the year.

High yield and disease resistant plant varieties should be introduce.

Integrated and balance use of available water sources (surface ground water) and should be made.

Weeds and pest should be efficiently controlled, integrated pest control particles should-be preferred over total reliance on chemical pesticides.

Combining use of traditional methods/equipment with modern methods/equipment of agriculture

6.5.1 Limits of increasing food productton There are ecological limits to how much food can be produced, and there are growing signs that such limits have been or soon will be reached in some parts of the world. Even if agricultural technology and biotechnology enhance productivity, the environmental impacts associated with food production impose limits on the amount of food the earth can produce. Continuing to increase inputs of fertilizer, water and pesticides eventually produces no additional increase in the crop yields as the J- shaped curve of crop productivity slows down, reaches its limits, levels off and becomes as S-shaped curve. Grain yields per hectare are still increasing in almost every country, but at a much slower rate. Worldwide, such yields dropped from an annual 2.3% increase between 1950 and 1984 to 1% annual increase between 1984 and 1993. Since 1985 yields for the major grains in the three countries with the highest yields per hectare - USA (=corn), Great Britain (wheat), Japan(rice), have leveled off. Future increases in food yields per hectare on existing cropland will result from improved strains of plants and from expansion of green revolution technology to new parts of the world.

Loss of genetic diversity limits crop yields Industrialized agriculture accelerates the loss of biodiversity that can be limit of genetic raw material needed for future green and gene revolution Forexample in India, which once had 3O, OOO varieties of rice, more than 75% of all rice production now comes from 10 varieties. We are rapidly shrinking the world's genetic "library" just when we need it more. Limits in cultivating more land


43

Between 1980 and 1990 the area of the world’s cropland expanded by only 2%. Theoretically, the world’s cropland should be more than doubled by clearing tropical forests and irrigating arid land; about 83% of this potential new cropland is in the rain forests and savannah grasslands of south America and Africa. Clearing rain forests to grow crops and graze livestock, however, can have disastrous consequences and potential cropland of savannah and semi-arid land in other Africa cannot be used for farming or livestock grazing because of presence of 22 species of the tsetse fly. The conversion of grain land into non-farm uses and to high-value crops has resulted in to 52% drop in grain land in Japan since 1960. Since 1970s South Korea lost 42% of its grain land and Taiwan 74%.

6.6 Environmental impacts of agriculture:

In the early years of human existence on this earth, man was just a hunter, gatherer and was quite like other animal species. Some 10,000-12000 ago he took to agriculture by cultivating plants of his own choice. He used the practice of slash and burn cultivation or shifting cultivation. The type of agriculture practiced these days is very different from the traditional ones and their outs in terms of yields as well as their impacts on the environment shows lots of differences.

6.7 Impacts of Traditional Agriculture on Environment Traditional agriculture usually involves simple tools, naturally available water, organic fertilizer and a mix of crops. This is more near to the natural conditions and usually it results in low production. The main impacts of this type of agriculture are as follows: Deforestation: The slash and burning of trees in forest to clear the landfor cultivation and frequent shifting result in loss of forest cover Burning of trees also causes air pollution. Soil erosion: Clearing of forest cover exposes the soil to wind, rain and storms, thereby resulting in loss of top fertile layer of the soil. (3) Depletion of nutrient: During stash and burn the organic matter in the soil gets destroyed and the most of the nutrients are taken up by the crops within short period, thus making the soil poor in nutrient, which make the cultivators shift to another area.

6.8 Impacts of Modern Agriculture on Environment Modern agriculture makes use of hybrid seeds of selected and single crop variety. High-tech equipment and lots of fertilizer, pesticides and irrigation water, the food production has increased tremendously as evident by “green revolution”. However, it also gave rise to several problems as discussed below: Fertilizer related problems


44

Fertilizers are the material added to the soil to restore and enhance the soil productivity for better growth of plants. Excessive use of fertilizer causes problems like: Micronutrient imbalance: most of the chemical fertilizers used in modern agriculture have nitrogen, phosphorus and potassium which are essential Micronutrient imbalance which affect the productivity of soil.

Nitrate pollution: Nitrogenous fertilizers applied to the fields often leach deep into the soil and ultimately contaminate the ground water. The nitrates get concentrated in the water and if their concentration exceeds 45 mg/l, they cause “Blue Baby diseases” or methamoglobinemia. This disease- affects the infants up to 6 months and in extreme case can cause death.

Eutrophication: Excessive use of N and p fertilizers causes problem related to the water bodies like lakes. A large portion or nitrogen and phosphorous present in the fertilizer is washed off and along with runoff water reach the water bodies causing over nourishment of the lakes which is called Eutrophication (eu=more, trophic=nutrition),Due to Eutrophication the lake, gets invaded algae blooms. Algae grow very fast using these nutrients. Algae complete their life cycle very quickly and die thereby adding- a lot of dead organic matter. Oxygen is consumed in the process of decomposition and very soon the water gets depleted of dissolved oxygen, this affects the aquatic ecosystem severely and ultimately anaerobic conditions are created where only the anaerobic bacteria can survive.

Problem related to pesticides Chemical compounds that are used for the control of pests are called pesticides. Although these pesticides have gone a long way in protecting crops from the huge losses occurring due to pests, yet they have number of side effects, as discussed below:

Biological magnification: Many of the pesticides are non-biodegradable and keep on accumulating in the food chain, a process called as biological magnification. Since human beings occupy higher tropical level in the food chain, hence they get the pesticides in bio-magnified form which is very harmful.

Death of non-target organisms: Many pesticides are broad spectrum poisons which not only kill the target species but also the several non-target species that are useful to us.

Creating resistance in pests and producing new pests: some individuals of pest species usually survive even after pesticide spray. The survivors give rise to highly resistant generation. About 20 species of pests are now known which have become immune to all types of pesticides and are known as “super pests”. Water logging Over irrigation of croplands by the farmer for good growth of their crop usually leads to Water logging. Inadequate drainage cause excess water to accumulate underground and gradually forms a continuous column with water table. Under water logged condition, pore spaces in the soil gets completely filled with water and no air is left in the pore spaces. The root of plants does not adequate air for respiration. As a result the yield of crop decreases.


45

Preventing excessive irrigation, sub-surface drainage technology and bio-drainage with trees like eucalyptus are some of the remedial measures to prevent water logging.

6.8.2 Salinity problem: A major cause of salinization of soil is excessive irrigation. About 20% of the world’s total cropland receives irrigation with canal water or ground water which unlike lake water often contains dissolved salts. Under dry climate, the water evaporates leaving behind salts in the upper layer of soil. At present one third of the total cultivable land area of the world is affected salts. In India about seven million hectares of land are estimated to be affected by salinity. Most of the crops cannot tolerate high salinity so the yield of the crop decreases. The most common method for getting rid of the salts is to flush them out by applying more quantity of good quality water to such soils.

6.9 Land resources Land is a major constituent of the lithosphere and is the source of many materials essential to man

and other organisms. it forms about 115th

of earth’s surface, covering approximately 13,393 million

hectares. Land is finite and important resources for Mankind and other organisms. Most human or natural activities need for their development. This space is provided by land. The living organisms, plants and vegetation are supported by land. It also contains resources like minerals organic as well inorganic matter and to some extent air and water. Lithosphere plays as important role as is not only produced food for human beings and animals, but also the decomposition of organic matter is carried out by a most of organisms in the soil.

Various uses of land

Food production

Houses the living spices, water resources & raw materials resources (minerals & ores)

Industrial purpose

Residential purpose

Commercial purpose

Waste disposal


46

Energy purpose

Land is (generally the top soil) can be considering as renewable resources if utilized carefully. The roots of trees and grass bind the soil. But if the forest are depleted or grass land overgrazed, soil erosion i.e. loss of top productive soil occurs and the land becomes unproductive. Intensive irrigation leads to water logged and Salinized soil on which crop cannot grow.

Land is also converted into nonrenewable resources when highly toxic industries and nuclear waste is dumped in it.

If managed efficiency, this natural resources has long term sustainable potential for food production.

Increasing human population has put a great pressure on this natural resource which is not available in unlimited quantity.

vast tracts of rand have been cleared of the natural vegetation for cultivation of crops and for plantations - bringing more and more land under the plough for the increasing human population, without applying sound ecological principals for the use of rand has put a great pressure on land resources.


47

7 CHAPTER: 7 HUMAN POPULATIONS AND ENVIRONMENT

7.1 Important terms:

POPULATION: It may be defined as a group of organisms of the same spices occupying a particular

space. Population Density: it is defined as number of the individuals per unit area per unit volume of the environment.

7.2 Habitation patterns and factors governing human settlement: In the beginning of life on earth, people started living in forests near the river banks to have easy access of food, water and shelter. There was no society and people were identified on the basis of their groups, the human settlement is developed collectively and their interaction. As population increased, people started moving from one place to another, and so revaluation in the field of transportation started. As time passed the use of fire to cook the food, using animals as a means of transport and their milk as a food supplement, lead human towards formation of wider group and they started to leave together. Different environmental factors governing human settlement are: Land , Food, Water , Energy resources, Forest resources , Shelter , Air Land: As population increased, people started taking over more and more land for human settlements. They construct roadways, railways, public complexes and industries. These activities caused environmental degradation due to large amount of air, water and land pollution and deforestation. The present day requirement is the availability of fertile land. 2. Food: Ancient man was dependent on animals for food. They do hunting of animals for their food. As the population increased, demand for more land for agriculture also increased. Development of advanced technologies in the fieldof agriculture caused use of fertilizersand pesticides for increasing production of crop, which deteriorated the quality of environment and health of common beings. 3. Water:


48

As the population increased, due to shortage of water and also due to pollution of surface water bodies (like rivers, lakes, and ponds) people started the use of ground water in terms of open wells for drinking purposes. Today the problem of water scarcity is due to unequal distribution of water resources, unplanned use of water resources, urbanization and industrialization, etc. 4. Energy Resources: Earlier man was using fire for cooking food in forests. They started using animals as a means of transport. But, with increase in population the use and demand of conventional energy sources (oil, petrol, gas, diesel, etc.) has considerably increased leading to depletion of these sources. 5. Forest resources: Earlier man started living in forest as the food was easily available, with increase in population demand of more land for human settlement and agriculture also increased. People cleared forest land for agriculture as well as for human settlement. This caused a problem of deforestation and serious effect on wildlife. 6. Shelter: Earlier man started living in forest, then he moves to caves. With increasein population people started settling by constructing huts, kuchha houses, etc. thus forming small colonies. Gradually these colonies expanded to present villages, towns and cities. By doing So, they separated themselves from the forest ecosystem and thus created on imbalance in the ecology of nearby forest area. 7. Air: Air is the basic requirement for men. Earlier days there was not a problemof fresh air. But today due to excessive air pollution the air quality has deteriorated. The people search to settlethemselves in pollutionfree atmosphere.

7.3 Over population (Population pollution)

Over population refers to a condition when an organism numbers exceedthe carrying capacity of its habitat. The maximum carrying capacity of environment is the capacity to support human beings with the availability of food, water, air and shelter as well as protecting human beings against extremities in environment. Population pollution is the pollution caused due to over population. Over population generally refers to population of human in particular area of stateor notion. In practice a particular area may be called having over population when it is difficult to sustain with available resources of that area.


49

Reasons for overpopulation: 1. Increase in birth rate: The crude birth rate is the number of child's birth per 1000 people' per year. lf the birth rate is high, it implies that more number of people will be for human settlement and will therefore cause over population. Factors affecting birth rate are :

fertilityrate of women

social beliefs

government Policies

recreation facilityavailable

Decrease in death role: The crude death rate is the number of deaths per 1000 Personsinyear. Decrease in death rate has resulted in overpopulation. The low death rate is due to following reasons: advancement in the field of medical science increase in nutrient levelsincrease in standards of diet improvement in quality of drinking water, etc

Increase in immigration: People from towns and villages generally migrate to cities in search of jobs and better living standards results in overpopulation of cities. The countries like U.S.A., Canada, U.K. and Australia, where industrial development had brought good environment for citizens to stay, earn and enjoy had resulted in immigration and ultimately overpopulation. 4. Better medical facility: The new inventions of medicines and awareness towards better health in the society have resulted in decreased crude death rate. Better medical facilities and healthcare services have controlled the spread of epidemic and certain diseases and reduced mortality rote and raised the life expectancy.

7.4 Population growth: Population growth is the change in population overtime and can be quantified as the change in number of individuals in a population using per unit time for measurement. The population growth can be expressed by population growth rate is expressed the fractional rate at which the number of the individuals in a population increases. Exponential growth and logistic growth of population are includes. Theories of populations:


50

7.4.1 Malthusian theory Malthusian theory was founded on two assumptions: Food is necessary for the existence of humankind Passion between the sexes is necessary and will remain unchanged. According to Malthus population tends to grow at a faster rate than the food supply population tend to grow at the geometrical manner where as food supply can only increase arithmetically this according to him is the cause of poverty ,disease, starvation and crime.

Malthus concluded that power of population is indefinitely greater than the power of the earth to produce subsistence for man. A point will come when the population growth will out strip food growth while is called point of crisis.

He also believed that checks will develop to keep the rate of population growth in line with the rate of growth of food supply.

He gave two types of the checks positive checks like famines diseases outbreak, war etc. and the preventive checks and preventive checks like control of birth rate. Limitation of the Malthusian theory: He never seriously discusses the feasibility of the control of the population. He failed to consider the possibility that development in the agriculture technology might permit sufficient increase of the supply of the food. He confused the instinctive desire for sexual relationship with the desire to have the children increase level of education and affluences tend to introduce distinction between sexual desire and decision to have children.

7.5 Population explosion: If a population of spices increases suddenly it is called population explosion. On the other hand if the population of an organism decreases suddenly, it is called population crash. Effects of population explosion: Over stress of the natural resources: As a population increases more resources are needed to meet over basic requirements. To meet this requirements more and more natural resources like water, land, forests etc. has to be explored Increase in demand of food will reach unpressedental levels


51

Over production of waste: Over population results in generation of more sewage, industrial effluents and solid waste. Discharge of these wastes results in imbalance. Other effects: unemployment, low living standards, pressure on agricultural land, low per capita income, high crime rate, environmental damage, migration in urban area in search of job, Energy crisis, Overcrowding of cities leads to development of slums.

7.5.1 Demographic transition or Demographic Transition Theory The theory of demographic transition describe the process of shift from high birth and death rates to low birth and death rates as a result of economic development of country, from pre-industrial to industrialized economy. lf birth and death rates were equal a zero population growth rate would result which is called "Demographic Transition”. Thus, Population growth is usually related to economic development. There occurs o typical fall in death rates and birth rates due to improved condition of living leading to low population growth, o phenomenon is called demographic transition. Fig shows the different stages of Demographic Transition. It is associated with urbanization and growth which occurs in following four phases:

1st

phase - Pre industrial phase:

It is characterized by high growth and death role and net population growth is low.

2nd

phase - Transitional Phase:

It occurs with rapid industrialization of developing country providing better hygiene and medical facilities and food reducing deaths. Birth rate is high so population show 2.5 - 3% growth rate. This Produces imbalance and country in this stage experiences o large increase in population, India is in the second stage of demographic transition and experiencing heavy population growth.


52

(c) 3rd

phase - industrial Phase:

There is fall in birth rates thereby lowering growth rate. Here birth rates fall due to access to contraception, increase in wages, urbanization, increase in status and living standards, educations amongst women and other social changes. Population begins to level off.

(d) 4th

phase - Post industrial phase:

Zero population growth is achieved. Here low birth rate and low death rate is observed. Birth rates may drop below replacement levels as in developed country lead ingot decline in population. Death rates may remain low resulting in an aging population growth as observed in developed countries.

7.6 Control of Population Growth: 1. Education: Literacy plays on important role in checking population growth. Improvement of literacy rate in villages and lower and middle class of people, particularly in women can control the population growth. This has been amply demonstrated by the Kerala state experience. 2. Living standards and employment: Employment will improve the living standards of people. It is common experience that people with high living standards have fewer numbers of children and smaller family size. This is evident in western countries. 3. Incentives: Incentives such as scholarships to children, subsidies, exemption from tax to smaller families, promotion in jobs, etc. should be offered. Two-child norm should be advocated. 4. Government benefits: The government benefits should be allowed only for those having smaller families. The families having more than specified number of children should be denied of such benefits. 5. Publicity: The importance of birth control, the significance of family size, and related information should be effectively published through various media, school books and other sources URBANIZATION Growth in the proportion of a population living in urban area is called urbanization. According to the UN, an urban area may be defined by the number of residents the population density the percent of people dependent on the agriculture, or the provision of the such public utilities and cervices as electricity and education.


53

7.7 Urban population Growth:

The number of the city with over one million people or more population in the urban

centers While the corresponding figure for less development countries. It is expected that

60 percent the world populations will be in the urban area by 2030 and that most urban

growth will occur in less development countries.

In developing and less development technologies urbanization results due to demographic

and economic pressure

People migrate to bigger urban centers to seek jobs and other social services such as health

and educations.

Environmental and socio Economic problems due to urbanization;

Demand of dwelling place

Over crowding

Pressure on medical services

Increase crime

Exploitation of ground and surface resources

Increase crime

Air pollution

Generation of solid and liquid waste

Pressure on wild life on and domesticated animals


54

INTRODUCTION TO ENVIRONMENTAL POLLUTION

Environmental pollution can be defined as any undesirable change in the physical, chemical

or biological characteristics of any component of the environment (i.e. air, water and land)

which can cause harmful effects on various forms of life or property. Environmental pollution dates back to the time when man discovered the use of fire. The burning of fossil fuels (coal, oil, natural gas) and wood releases a number of

poisonous gases into the atmosphere. Causes of pollution Natural causes Man-made causes Volcanic eruptions Commercial activities Earthquakes Industrial activities Storms and dust Urbanization UV radiations Insecticides, pesticides Decay of organic matter Organic chemicals Use of vehicles Mining At the beginning of the human civilization our environment was pure, virgin and uncontaminated. It was most supportive and hospitable to living organisms. The advancement of science and technology led to the exploitation of natural resources. Pollutant A pollutant may be defined as any substance present in the environment in such concentration that alter the quality of environment and affect the living things adversely. Or Pollutant is defined as the substances that actually cause pollution.

TYPES OF ENVIRONMENTAL POLLUTION Water pollution

Air pollution

Land pollution

Noise pollution

Thermal pollution

Marine pollution


55

8 CHAPTER: 8 WATER POLLUTION

8.1 Introduction

Water is one of the basic necessities of all the living organisms. Life cannot exist without water. Two third of human body comprises of water.

About three fourth part of our earth is made up of water. Although there is water everywhere, very little water is in usable form.

Less than 1% is available for human use in the form of surface waters as 97% is contained in oceans and sea and 2% is locked up in ice caps and glaciers.

Again in search of better quality of life, man has introduced lots of toxic materials in to the water, making it unsafe for many purposes including drinking.

It now becomes the responsibility of every citizen to think about the problem and solve it.

8.2 Water pollution Water pollution can be defined as alteration in physical, chemical or biological characteristics of water through natural or human activities making it unsuitable for its designated use. Or Any physical, chemical or biological change in water quality that adversely affects living organisms or makes water unsuitable for certain uses is referred as water pollution.

Fresh water present on the earth surface is put to many uses. It is used for drinking, domestic and municipal uses, agriculture, irrigation, industries, recreation etc.

The used water becomes contaminated and is called waste water which contains residues of the activities taking place in each of them.

Thus passing through these industries, agricultural lands and the urban settlement the water gets soiled up or polluted and is loaded with organic and inorganic chemicals, pathogenic and non-pathogenic organisms and becomes unfit for human consumption.

8.2.1 Signs of polluted water Bad taste of drinking water.

Offensive odours form rivers, lakes and oceans.

Decrease in number of fish in fresh water and sea water.

Oil and grease floating on the surface.


56

Unchecked growth of aquatic weeds in water bodies.

Presence of colour due to organic matter.

Potable water

The water which is suitable for drinking is known as Potable water or Whole some water.

It is free from impurities, but essentially consists of some minerals in order to give some taste.

The potable water should have the following qualities:

It should be odorless and colorless.

It should be free from suspended solids and turbidity.

It should be free from toxic substances.

It should be free from pathogenic organisms. It should have good taste.

It should be aesthetically pleasant, i.e. cool and fresh.

8.3 Types of water

Pure form of water: In the form of H2O, also known as distilled water.

Mineral water: Water with acceptable limits of minerals specified by potable water standards.

Tap water: Water supplied by the concerned authority available at homes.

Polluted water: Water containing impurities not suitable for drinking.

Contaminated water: Water containing harmful impurities, not suitable for any purpose nor even can be thrown in water bodies.

8.4 Water quality standards

The definition of water quality depends on intended use of the water which may be either human consumption or it may for industries, irrigation, power generation, recreation etc.

Depending upon the purposed use of water, certain quality criteria are established and based on these criteria, quality standards are specified by health and other regulating agencies to ensure that the water quality is as per the proposed use.


57

Different types of water use require different levels of water purity.

Drinking water requires the highest standards of purity whereas water of relatively lower quality is acceptable for other purposes like agriculture, industry, hydroelectric

power generation, recreation etc.

8.4.1 Water quality parameter: Main parameters which are required to be tested for determining the quality of water can be divided into. (1) Physical (2) Chemical (3) Biological/Microbiological Physical parameters

1. Turbidity

2. Colour

3. Odour

4. Taste

5. Temperature Chemical Parameters

1. Solids (suspended, dissolved, volatile)

2. Hardness

3. Chlorides

4. pH

5. Dissolved gases like Oxygen Carbon Dioxide, Hydrogen Sulphide

6. Nitrogen compounds like Nitrites, Nitrates, Ammonical Nitrogen, Albuminiod Nitrogen

7. Metals and other inorganic substances like Fluoride, Iron & Manganese, Lead, Arsenic, Iodides, Boron Cadmium

Biological parameters In Biological parameters includes various microorganisms like bacteria, virus, protozoa, worms present in water it may be pathogenic or non-pathogenic The agencies playing an important role in specifying the norms for various effluents to be discharged in the water bodies as well as for drinking water are:

Indian Standards Institution (ISI)


58

World Health Organization (WHO)

United States Public Health Services (USPHS)

Indian Council of Medical Research (ICMR)

8.5 Sources of Water Pollution Sources of water pollution can be classified as Point Sources

Those sources which can be identified as a single location are called point sources.

Examples of point sources are industrial effluent, power plants, sewage discharge etc.

It is possible to minimize the water pollution from the point sources if the waste water is collect and is given some treatment before it is discharged into a water body.

Non point sources

Non point sources which are also called as area or diffused sources.

Those sources whose location cannot be easily identified are called non point sources.

The discharge from this sources is not at any particular site, rather these are scattered, which individually or collectively pollute the water.

Example of non point sources are surface runoff from agricultural fields, overflowing small drains, rain water sweeping roads and fields etc

Major sources of surface water pollution are: Sewage: discharge of sewers and drains.

Industrial effluents from different industries.

Synthetic detergents used for washing and cleaning.

Agrochemicals like fertilizers containing nitrates and phosphates and pesticides used in agricultural fields which come in runoff from the agricultural land.

Oil spillage during drilling and shipment.

Waste heat from industrial discharge increases the temperature of the water bodies.

Major sources of ground water pollution are septic tanks, deep well injection of industrial effluents, mines etc.


59

8.6 Classification of Water Pollutants Water pollutants can be classified into the following categories

8.6.1 Organic pollutants: The organic pollutant means “oxygen demanding pollutants”.

The organic pollutants are present in domestic sewage, plant nutrient, oil waste from food processing industries, tanneries, dairy, pesticides waste etc. The agencies playing an important role in specifying the norms for various effluents to be discharged in the water bodies as well as for drinking water are:

Indian Standards Institution (ISI)

World Health Organization (WHO)

United States Public Health Services (USPHS)

Indian Council of Medical Research (ICMR)

8.6.2 Pathogens

Many wastes water especially sewage contains many pathogenic microorganisms which are usually contained if faces and urine of infected persons.

Water borne dieses like cholera, dysentery, typhoid, bacillary dysentery are caused due to pathogens present in water.

8.6.3 Nitrogen and phosphorus compounds (Nutrients)

Additional of compounds containing nitrogen and phosphorus helps in growth of algae and other plants. These compounds are nutrient for growth.

When these concentrations are high it causes rapid growth causing algal bloom. Also the growth of weeds increases.

It covers up the water surface and prevents entry of sunlight into water bodies.

Aquatic plants along with algae thus die; the bacteria present in water now decompose all these dead plants.

The decayed organic matter adds unwanted colour, odour and taste to water. It also reduced DO of water and leads to death of fish and other aquatic animals.

Toxic Compounds

Pollutants such as heavy metals, pesticides, cyanides and many other organic and inorganic compounds are harmful to aquatic organisms.


60

Some of the substances like pesticides, methyl mercury etc moves in to the bodies of organisms from medium in which these organisms live.

These substances tend to accumulate in the organisms body. This process is called Bio accumulation.

The concentration of these toxic substances builds up at successive levels of food chain. This process is called Biomagnifications.

Following example of biomagnifications of DDT in aquatic chain.

Components DDT Concentration (ppm)

Birds 10.00

Needle fish 1.0

Minnows 0.1

Zooplankton 0.01

Water 0.000001

Mercury dumped in water is converted to methyl mercury by bacterial action. A disease called Minimata dieses occurs due to consumption of methyl mercury contaminated fish.

Concentration of nitrate more than45 mg/L causes occurs blue baby diseases in infants.

Excess fluoride causes fluorosis. It is effects the bones and teeth of the person.

Suspended matter

Makes water aesthetically displeasing.

Biodegradable suspended matter causes DO depletion.

It reduced light penetration there by reducing photosynthesis and a corresponding loss in food production.

Provides adsorption sites for harmful chemicals or biological organisms which can Effect flora and fauna of stream.

8.6.5 Thermal discharge

Water is used for dissipation of waste heat in power plant and industries. This heated water is subsequently discharged into water bodies. Increased temperature of water has following effects:


61

Increases biological activities.

Cause death of some heat sensitive organisms.

DO concentration decrease this together with increased biological activities at high temperature may result into anaerobic condition. Resulting in bad odour.

Growth of algae increases.

Toxicity of chemical pollutants increases with increases in temperature. 8.6.6 Eutrophication

The word Eutrophication is originated from Greek words eu=well and trophes= food. Thus meaning is “well fed” or “nutrient rich”.

Thus we can define eutrophication as excessive nutrient load in a water body or enrichment of water body by nutrients like phosphorus and nitrogen.

Presence of nutrients is must for growth of organisms, bur if these nutrients are present in excessive amount then they act as pollutants because they allow

Excessive growth of aquatic plants like algae.

Depending upon the presence of nutrients, the water bodies (aquatic system) may be classified as under:

Oligotrophic: Water bodies with poor concentration of nutrients and very low productivity of aquatic plants

Mesotrophic: Water bodies with moderate concentration of nutrients and average productivity of aquatic plants

Eutrophic: Water bodies with high concentration of nutrients and very high productivity of aquatic plants What causes eutrophication?

Newly formed water bodies such as lakes, ponds and reservoirs, whether natural or man-made has low nutrient content and low plant productivity.

Gradually, with the passage of time these water bodies become rich in nutrients through the deposit of domestic waste, agricultural residue (rich in nitrogen and phosphorus), and industrial waste etc which ultimately increase aquatic growth.


62

In this way the oligotrophic water bodies turns gradually into Mesotrophic water body.

Natural eutrophication is a very slow process, often taking more than 100 years. But artificial eutrophication is very fast as it depends on the input of organic waste matter.

The aerobic decomposition of organic waste in the presence of oxygen by bacteria leads to eutrophication.

The nutrient rich water body supports the growth of algae and the entire water body becomes green.

As more plants grow due to the additional supply of nutrients, more plants also die.

Bacteria decompose these dead plants and organic waste using dissolved oxygen. As a results, BOD of water increases.

Fish and other aquatic animals start dying due to the depletion of oxygen. Such a water body is said to be eutrophied.

With an increase in BOD, water starts emitting an offensive smell and asthetic and recreational importance of the water body decreases.

Generally, it is observed that concentration of nitrogen higher than 0.3 mg/L and phosphorus more than 0.15 mg/L cause eutrophication.

Effects of eutrophication: 1. Higher growth rate of algae in the water body.

2. Algae bloom restrict the penetration of sunlight in water body hence rate of photosynthesis

process decreases.

3. Decrease in dissolved oxygen (DO) and increase biological oxygen demand (BOD).

4. Bad taste, bad odour is produced and also increases in turbidity of water.

5. The decaying organic matter causes depletion of DO, destroying fish and other aquatic species.

6. Aesthetic and recreational importance of the water body decreases i.e. fishing, swimming,

boating etc. Control of eutrophication

1. Eutrophication can be controlled by:

2. The control at sources is the best practice to prevent eutrophication therefore waste water enrich with nutrient should be treated for removal of nitrogen, phosphorus and carbon before disposal.


63

3. Recycling of nutrient should be adopted.

4. Algae bloom should be removed the water body.

5. Reducing the use of phosphate in detergents.

6. Reducing the use of nitrate containing fertilizers. The growth of algae can be control by

using precipitants like alum, ferrous sulphate and sodium aluminates but it is very costlier affair and may be harmful to other aquatic life.

7. The phosphorus can be removed by precipitation and nitrogen can be removed by

nitrification. The denitrification, reverse osmoses, ion exchange and electro dialysis are the advanced treatment for the removal of dissolved nutrients.

8. It can also be reduced by applying the methods to reduce soil erosion.

9. The copper sulphate and sodium arsenite are also used to kill algae growth but these are

not favorable practice.

8.7 Control of water pollution Water pollution can be checked or at least reduced by following measures: By proper sewage treatment: The sewage should be properly treated before disposing it in any water bodies. Sewage should be given following treatment before discharging into water bodies

1. Primary treatment:

To remove floating impurities, girt, inorganic particles, settable solids etc. It mainly involves physical method for removal of impurities.

2. Secondary treatment:

Mostly aimed to remove organic impurities using mainly biological methods

3. Tertiary treatment:

Mostly using strong oxidizing agents to remove impurities, Example chlorine gas is used to remove the impurities remaining after primary and secondary treatment.

The industrial effluent should be properly treated before discharging it into water bodies.

By enforcing stringent standards for disposal of sewage and industrial waste into water bodies

By prohibiting direct washing of clothes and animals in water bodies used for drinking water supply.


64

Pesticides and fertilizers should be judiciously used to reduce chemical pollution due to surface runoff from farms. Less stable pesticides should be used.

Increasing the vegetative cover to reduce water pollution due to soil erosion

Encouraging reuse of water

To avoid thermal pollution hot water should be cooled before releasing it into bodies

Advanced treatment for removal of nitrates and phosphates should be adopted to prevent

eutrophication. MARINE POLLUTION

8.8 Marine pollution: Marine pollution can be defined as the introduction of substances to the marine environment directly or indirectly by humans, resulting in the adverse effects such as hazards to human health, obstruction of marine activities and lowering of the quality of sea water. Sea is a major sink or reservoir for all the pollutants. Pollutants can enter the sea directly from the outfalls and sometimes from coastal towns, but most frequently they enter from estuaries. Pollutants also reach the sea indirectly from rivers which receive many pollutants from their catchments. Marine pollutants can be classified into six broad categories:

Organic waste

Oil

Heavy metals

Heat

Pesticides and herbicides

Radioactive substances 8.8.1 Causes or sources of Marine Pollution There are some specific causes that pollute marine waters

The most obvious input is through pipes/outfall directly discharging waste into the sea. Sewage from the residences and hotels in coastal towns are directly discharged in the sea.

Off shore oil exploration and extraction also pollute the seawater to a large extent.

Tankers transporting oil contribute to marine pollution significantly.


65

Ship accidents and accidental spillage of oil, other materials at sea can be very damaging to marine environment.

Pesticides and fertilizers from agriculture, which are washed off the land by rain, enter water courses (rivers) and eventually reach the sea.

Petroleum and oils washed off from roads normally enter the sewage system but storm water overflow carry these materials into rivers and eventually into the seas.

8.8.2 Effects of marine pollution: The major effect of marine pollution is on the aquatic ecosystem

Disposal of large amount of organic waste in to sea causes phytoplankton blooms or red tides causing discolourisation of the whole area of water.

Oil spill have damaging impacts on marine and bord species, and salt marches.

An impact on commercially important marine species, reducing the market value of sea.

Drill cuttings dumped on sea bed create anaerobic conditions and result in the production of toxic sulphides in the bottom sediments, thus eliminating the benthic fauna.

Contaminated sea water imparts an unpleasant flavor to the fish and sea food and is detectable even at extremely low levels of contamination. Thus there would be significant economic loss to the sea food industry.

8.8.3 Control of Marine pollution: Sewage should be given complete treatment before disposing it in to the sea.

Toxic pollutants from the industries should not be discharged in to the sea.

Dumping of toxic, hazardous waste and sewage sludge should be banned.

Oil ballast should not be dumped in to sea.

Development activities on the coastal areas should be minimized.

Runoff from the non-point sources should be prevented to reach coastal areas.

Ecologically sensitive coastal areas should be protected by not allowing drilling.


66

9 CHAPTER: 9 AIR POLLUTION

9.1 Definition “Air pollution is the presence in ambient atmosphere of substances, generally resulting from the activities of man in sufficient concentration, present for a sufficient time and causes the harmful effect on humans, plants and animals.” Or “Air pollution is defined as the presence of unwanted and undesirable foreign particles and gases (in sufficient quantity and duration) in the air which may have adverse effects on human being, animals, plants, vegetation and important structures.”

9.2 Composition of Air

Atmospheric air is a mixture of various gases, water, vapour and fine particulate matters.

The major gases in a pollution free dry air are Nitrogen (78%), Oxygen (21%), Argon (0.9-1.0%).

The minor gases include Neon, Helium, Methane, Hydrogen, Hydrogen and Ozone etc. Table: Composition of clean dry air

Constituent Concentration

Nitrogen 0.7808

Oxygen 0.2095

Argon 0.0093

Carbon dioxide 355 ppm

Neon 18 ppm

Helium 5.2 ppm

Methane 1.8 ppm

Krypton 1.1 ppm

Nitrous oxide 0.3 ppm

Hydrogen 0.5 ppm

Ozone 0.01 ppm

Most of the above values remain practically unchanged with respect to time.

However the concentration of carbon dioxide is increasing by about 1.5 ppm per year as a result of deforestation and increased air pollution from industries and automobiles.

9.2.1 Structure of Atmosphere


67

On the basis of temperature profile and other related phenomena, atmosphere is divided into five major layers. 9.2.1.1 Troposphere

It is the lower most layer of atmosphere in which most living organisms exist.

On an average it extends up to 10-11 km from the earth surface.

The air near the ground level is heated by the radiation from the earth, but the temperature decreases uniformly with altitude.

The cold layer at the top of the troposphere, which shows a temperature inversion, that is a negative to positive lapse rate, is known as tropopause.

9.2.1.2 Stratosphere

A stable layer of atmosphere above troposphere is called stratosphere. It extends about 50-55 km above the surface of the earth.

Stratosphere is known for the presence of ozone which is found at around 20 km from ground.

This layer of ozone is called ozonosphere and acts as a protective layer against the harmful effects of ultra violet radiations on living organisms.

The ozone molecule present in this layer, absorbs the sunn’s ultra violate radiation, and decomposes into oxygen molecules and an oxygen atom.

When these particles combine, energy is released as heat radiation which causes a positive lapse rate.

The layer separating stratosphere from mesosphere is called stratopause.

9.2.1.3 Mesosphere

It exists over stratosphere and in this layer temperature decreases with altitude because of low levels of ozone that absorbs ultraviolet radiation.

This layer is very special as all sound waves as well as short radio waves coming from earth are reflected from this layer.

9.2.1.4 Thermosphere/ ionosphere

Temperature increases rapidly with increases in height. The heating of this layer is due to absorption of the solar energy.

Ionizations of element like oxygen and nitric oxide take place in the upper most portion of layer.

Therefore, the upper layer of thermosphere is also called ionosphere.

9.2.1.5 Exosphere/ magnetosphere


68

The upper most layer of the atmosphere is called exosphere.

It exists above the thermosphere and extends up to 2000 km above the earth.

This layer is almost airless and empty.

It probably contains hydrogen gas in ionized state. It has very high temperature (>1200 °C).

9.3 Sources of Air Pollution Sources of air pollution can be mainly classified into Natural sources Man made sources Natural Sources:

Pollen grains

Volcanic eruption

Forest fires

Salt spray from oceans

Dust storms

Marshy land

Bacteria and other microorganisms

Spores

Photochemical reactions Man made sources

Industrial units

Thermal power plants

Automobile exhaust

Fossil fuel burning

Agricultural activities


69

Mining

Air crafts

Nuclear explosion

Domestic burning of woods Man made sources can be generally classified into:

9.3.1 (a) Point or Stationary sources: These are the sources which add pollutants to air from one particular point. E.g. Chimneys of different industries Pollutants from point sources affect only restricted areas.

9.3.2 (b) Line or mobile sources: The line or mobile sources of air pollution are the sources like automobiles, trains, ships, aeroplanes, etc. which emit exhaust into air along a narrow belt over long distance.

9.3.3 (c) Area sources: Area sources are locations from which air pollutants are emitted from a well defined area. E.g. release of air pollutants from industrial area of town or city which affects particular area.

9.4 Classification of Air pollutants The air pollutants can be classified on the following basis: (A)Classification based on origin According to the origin air pollutants can be classified into Primary air pollutants Secondary air pollutants Primary air pollutants: Primary air pollutants are emitted directly from the sources and are found in the atmospheres in the form in which they were emitted.

For Example SO2, NO2, HC, ash, smoke, dust, mist etc.

Secondary air pollutants: Secondary air pollutant are formed in the atmosphere by chemical interactions between primary pollutants and atmospheric constituents.


70

For Example Ozone, Sulphur trioxide, PAN, aldehydes, ketones etc. (B) Classification based on state of matter According to the state in which air pollutants are found in atmosphere, they are classified as Gaseous air pollutants Particulate air pollutants Gaseous air pollutants: Gaseous air pollutants are those air pollutants which are found in the gaseous state at normal temperature and pressure in the atmosphere.

For Example SO2, NO2, HC, CO, CO2etc.

Particulate Air pollutants: These include suspended droplets, solid particles or their mixtures in the atmosphere, commonly referred as particulates.

For Example aerosols, dust, smoke, fumes, mist, fog, flyash, soot, and natural particulates such as pollen grains, protozoa, fungal spores and volcanic dust

Air Pollutants Based on origin Based on states of matter Primary Secondary Gaseous Particulates

E.g. SOx, NOx, E.g. O3, SO3, E.g. CO, CO2, E.g. Dust, smoke,

Ash, smoke etc PAN etc SOx, NOxetc aerosol, fog etc

9.5 Air pollutants – Sources and Effects:

Carbon monoxide (CO):

It is colourless, odourless, tasteless gas.It has no effect at normal concentration (0.1ppm) but at higher conc. It seriously affects the human metabolism.


71

Sources:

Natural sources such as Volcanic eruption, natural gas emissions, electrical discharge during cloud forming, marsh gas production etc. contribute a small amount of CO in the atmosphere.

Transportation sources contribute about 64% of CO in air.

Forest fire and agricultural burning contribute about 17 % of in air.

Industrial processes such as electric furnace and blast furnaces in iron and steel industries, Petroleum refining, Paper industry, Gas manufacture, Coal mining etc.

Effect:

It reduces the oxygen carrying capacity of the blood by selectively combining with hemoglobin forming carboxyhemoglobin. This causes giddiness, laziness, and exhaustion.

It reduces vision and causes cardiovascular disorders.

CO is a very dangerous asphyxiant and its high levels are fatal to human life.

It may cause coma, respiratory failure and even death.

Carbon Dioxide (CO2): The content of carbon dioxide in the air has increased by approximately 15% during the last century

in spite of the fact that photosynthesizing green plants balance the CO2 - O2 ratio to a large extent.

Sources:

Fossil fuel burning

Agricultural practices (eg. Deforestation)

Forestry

Respiration process

Effects:

It is the main green house gas responsible for rise in average temperature of atmosphere.

CO2 is less dangerous than CO and cause nausea and headache.

Oxides of Nitrogen (NOx):


72

NOx group include six different oxides of nitrogen (NO, NO2, N2O, N2O3, N2O4, N2O5). Nitric oxide

and nitrogen oxide are very important pollutant. NO is colourless, odourless gas but is NO2 reddish

brown and have suffocating odour. Sources:

Fuel combustion in automobiles and industries.

Lightening

Forest fire

Bacterial decomposition of organic matter Effects:

Nitric oxide combines with hemoglobin and reduces the oxygen carrying capacity of blood.

NO2 is more toxic then NO and may affect lungs and cause bronchitis.

NO2 is reacting with atmospheric moisture to form nitric acid causes acid rain and affects

vegetables and metals. (3) Oxides of sulphur (SOx)

SOx include sulphur dioxide and sulphur trioxide. SO2 is colourless gas having pungent and

suffocating odour. Sources:

Most of the SOx pollution (67%) due to volcanic activities and other natural sources.

Burning of solid and fossil fuels

Transportation

Industries like paper mfg. plants, refineries, sulphuric acid plant

Open burning of refuse and municipal incinerator. Effects:

It causes cardiac diseases, asthma, bronchitis, eye irritation, throat troubles etc.

Long term exposures to high levels of sulphur dioxide gas causes respiratory illness and heart diseases.

Oxides of sulphur attacks building materials especially marbles and lime stone. (eg. Taj Mahal at agra)


73

SO2 react with moisture in atmosphere to form sulphuric acid which causes acid rain affects

vegetables and metals.

Oxides of sulphur may affect clothes, leather, paper and plants.

Hydrocarbon (HC):

The gaseous and volatile hydrocarbons are mainly responsible for air pollution.Common HC includes methane, ethane, acetylene etc.

Sources:

Coal fields

Natural fires

Incomplete combustion from car engines

Industrial sources (refineries)

Forest fires

Agricultural burning

Coal waste fires

Effects:

Some aromatic HC may cause cancer.

Unburned HC with oxides of nitrogen in the presence of sunlight from Photochemical oxidants (like ozone, PAN) which can have adverse effects on humans and plants.

Photochemical oxidants:

The major photochemical oxidant is ozone. Ozone is produced in the upper atmosphere by solar reaction; small concentrations of this gas diffuse downwards and become the major concern in the air pollution.

In the presence of sunlight, the oxides of nitrogen react with the unburned HC released by the exhausts of automobiles and following a series of complex reactions produce secondary pollutants like PAN, Ozone, aldehydes and Ketones etc.

Unburnt Hydrocarbon + NOx Abundant sunlight

Photochemical smog Sources:


74

Automobile exhausts

Effect:

Photochemical oxidants cause irritation of eye, nose and throat, headache etc.

Ozone damage chromosomes.

Ozone and PAN cause damage to plants by interfering with plant cell metabolism especially in leafy vegetables. Premature fall and yellowing of leaves are due to this pollutant.

• Photochemical oxidants also affect the materials like rubber, plants, textile fibers etc.

Particulate Air pollutants:

These are small, solid particles and liquid droplets present in the atmosphere in fairly large numbers and sometimes pose serious air pollution problems. The size of particulate ranges from 0.02 µ to 500 µ.

Aerosols: These include all air borne suspensions of solid or liquid particles smaller than 1 mm.

Dust: It consists of small solid particles (size 1 to 200 µm) and are generated by material crushing, grinding or blasting.

Smoke: It consist of fine solid particles (size 0.1 to 1 µm) resulting from the incomplete combustion of organic particles like coal, wood, tobacco or other chemical processes.

Fumes: These are fine solid particles (size 0.1 to 1 µm) formed by the condensation of vapours of solids materials.

Mist: It consists of liquid droplets formed by the condensation of vapours in the atmosphere or are released from industrial operation.

Fog: It the mist is made up of water droplets whose concentration is high and dense enough to obscure vision then the mist is called fog.

Fly ash: This consists of finely divided non combustible particles present in the gases arising from fuel combustion.

Soot: Incomplete combustion of carbon containing materials release carbon particles.

Natural particulates: Natural particulates are pollen grains, spores bacteria viruses, protozoa, fungal spores and volcanic dust.


75

Sources:

Volcanic eruption

Dust storms

Spraying of salts by oceans

Fly ash from combustion of fossil fuels

Smoke from vehicles

Mining

Agriculture burning

Effect:

Health effects - Particulates less than 10µm can enter deep into the lungs and may also get into blood streams. It can cause problems like irritation, aggravated asthama, chronic bronchitis and other lung diseases.

Particulates accelerate corrosion of metals, damages buildings, paints etc.

Aerosols (Fluorocarbons, NOx, SOx) released from emissions from jet and supersonic planes

deplete the ozone layer in higher atmosphere.

Dust coating on leaves affects photosynthesis and reduces plant growth.

Fly ash reduces pH balance and potability of water.

Metal dust containing heavy metals and cotton dust may also cause respiratory problem.

9.6 Effects of Air Pollution on Human Health:

Carbon monoxide (CO) and nitric oxide (NO) combine with hemoglobin to form carboxy hemoglobin (COHb) which reduces oxygen carrying capacity of blood.

Oxides of nitrogen (NOX) and oxides of sulphur (SOX) cause irritation to eye, throat and

nose. They an cause diseases like asthma and bronchitis.

Pollen can initiate asthmatic attacks.

Secondary pollutant (O3, PAN) produced by hydrocarbons and NOx, results in the formation

of photochemical smog, which causes irritation of eyes, nose, throat and respiratory diseases.


76

Some aromatic hydrocarbons may cause cancer.

Exposure to dust, smoke, smog and soot may include several respiratory diseases like asthma, bronchitis and lung cancer.

Heavy metals like lead may cause poisoning effects on nervous system, damage to kidney and vision problem.

Nickel particulates in tobacco smoke result in respiratory damage.

Radioactive substances cause lung diseases and affect kidney , liver, brain and sometimes may cause cancer.

Atmospheric dust containing silica may cause silicosis.

9.6.1 Effects of Air Pollution on plants and vegetation:

Air pollutants affect plants by entering through stomata (leaf pores through which gases diffuse), destroy chlorophyll and affect photosynthesis.

Pollutants also erode waxy coating of the leaves called cuticle. Cuticle prevents excessive water loss and damage from diseases, pests, drought and frost. Damage to leaf structure causes dropping of leaves.

Particulate like dust, fog, soot deposit on plant leaves, block stomata and affect the rate of transpiration.

Following are some of the effects of air pollutants on plants and vegetations.

Sr. No. Name of Pollutant effects on plants and vegetations

1 Sulphur dioxide (SO2) Loss of chlorophyll, bleached spots on leaves, necrosis

(killing of tissues).

2 Nitrogen oxide (NO2) Suppressed growth, premature leaf fall (abscission),

reduction in productivity.

3 Ozone (O3) Premature ageing, bleaching of leaves, necrosis,

destruction of vegetation

4 Fluorides Necrosis at leaf tip.

5 Ethylene Leaf fall, flower dropping

6 PAN Suppressed growth, Silvering of lower leaf surface,

damage to small plants

9.6.2 Effects of Air Pollution on Property/Material:

SO2 in the presence of oxygen and moisture is converted into H2SO4 acid. Deposition of this

acid on metal parts of building roofs, railway tracks, metal on bridges cause corrosion.


77

H2SO4 acid deposition reacts with limestone, marble and other building materials to cause

deterioration and disfigure the building material.

Pollutants like SO2, O3, H2S and aerosols damage protective coating and paints of the

surface.

Damage of textile dyes and textile fibers is caused by SOX, NOx and O3.

Ozone and PAN cause cracking of rubber tyres and various forms of electrical insulation.

Deterioration of lather and paper due to H2SO4 decomposition.

Soiling increases cost of cleaning shirts and other wears, windows, building surface.

9.6.3 Effects of Air pollutants on Climate:

Due to manmade activities like industrialization, automobiles, deforestation etc.,

concentration of CO2 and other green house gases in atmosphere will increases.

About 50% of Green House Effect may be attributing to CO2, which resulted in the increase

in temperature of earth. This increase in temperature caused the melting of ice caps and glaciers. Thus the increase in ambient air temperature will increase the mean sea level.

The thinning of the ozone layer in the stratosphere by the action of aerosols will increase the penetration of harmful ultraviolet rays to earth and this will cause blindness, Sunburn, inactivation of proteins, RNA and DNA.

9.6.4 Effects of Air pollutants on Aesthetic Beauty:

The most noticeable effect of air pollution on the properties of atmosphere is the reduction in visibility, which may lead to safety hazard.

Visibility is reduced by adsorption and scattering of light by air borne particles (0.1 to 1 µm size).

Industrial and automobiles emissions, sewage and garbage emit foul odours causing further loss of aesthetic beauty.

9.6.5 Factor affecting Air Pollutant: The factors which affect air pollution are as follows: Metrological parameters or characteristics:

Wind direction


78

Wind Speed

Atmospheric lapse rate

Relative Humidity, etc.

Topographical features:

Unevenness of land forms and barriers like mountains valleys.

Characteristics of pollutants:

Type and size of pollutants

Interaction among pollutants

Mode of release of pollutants:

Intermittent, continuous, cyclic

From single sources or multiple sources

From point sources or area sources

9.7 Control of Air Pollution:

Air pollution cannot be fully abated but can be controlled if certain measures are taken.

Preventive measures.

Control measures i.e. Control of gaseous/particulate pollutants from industry/automobiles using equipment.

1. Preventive measures These measures are mainly aimed at correction right at the source so there will be lesser amount of pollutant emitted from the industry/automobiles. Some of the important preventive measures are: Selection of suitable fuel:

Using low sulphur coal in power plants

Using natural gas in place of coal for power generation.

Using LPG/CNG instead of diesel or petrol in automobiles Modifications in industrial processes and/or equipments to reduce the emissions:


79

If coal is washed before pulverization, then fly-ash emissions are considerably reduced. Section of suitable site and zoning for industrial unit:

Zoning means setting aside separate areas for industries so that they are far from the residential areas.

This will help in proper dispersion of pollutants resulting in lower concentration of pollutants in the air of residential area.

a) By using proper environmental impact studies before setting the industry. Control measures When it is not possible to control air pollution at source some measure are to be adopted to control the level of pollution. The most common method of eliminating or reducing pollutants to an acceptable level include

a) Collecting the pollutants by using equipment to prevent its escape into the atmosphere.

b) Destroying the pollutants by thermal or catalytic combustion.

c) Changing the pollutants to a less toxic form.

d) By releasing the pollutants through tall chimneys for greater dispersion. Control of particulate matter: Particulate matter can be controlled by using following devices.

1. Gravitational settling chamber: It is used to remove particles with size greater than 50 µm.

Velocity of the flue gas is reduced in larger chamber thereby including settling of the particles under gravitational force.


80

2. Cyclone separators: Centrifugal force is utilized to separate the particulate matter from the gas.

As centrifugal force in much greater than gravitational force smaller particles can be removed (10 to 50 µm).

Cyclones are widely used in industries producing larger quantities of gas containing large sized particles like cement and fertilizer plants, petroleum refineries, asphalt mixing plants, grain mills, cotton gins, etc.

Fig Cyclone separator

3. Fabric filters (Bag house filters):

Fig. Fabric filters (Bag house filters)


81

In this device fabric filter’s out the particulate matter from the gas stream and allow clear gas to flow.

It can remove particles up to 1 µm. Control of Gaseous pollutants:

The gaseous pollutants can be controlled through the techniques of combustion, absorption and adsorption.

In combustion process oxidizable gaseous pollutants are completely burnt at a high temperature. This process is used to control gaseous pollutants in petro-chemical, fertilizer, paint and varnish industry.

In absorption technique effluent gases are passed through absorbers containing liquid absorbents that remove, treat or modify one or more gaseous pollutant. Liquid absorbent may utilize either chemical or physical changes to remove pollutants.

In adsorption, the air pollutants are adsorbed on a solid surface. Commonly used

Adsorbents are activated carbon, activated alumina, silica gel etc. Control of automobile Exhaust:

The un-burnt hydrocarbon in auto emissions can be reduced by use of efficient engines.

Catalytic convertor can convert NO to nitrogen gas and reduce potential hazards of NOx. It

can also reduce CO and hydrocarbon emission.

Using lead free petrol.

By using cleaner fuel like CNG.

By proper maintenance of the vehicles.

Developing good mass transportation facility


82

10 CHAPTER: 10 LAND, NOISE AND THERMAL POLLUTION

10.1 Land pollution

10.1.1 Introduction:

Land is considered as important resource of earth as it is source of many materials essential

to man and other organisms and is essential medium for development of agriculture,

forestry, vegetation etc.

Land is a major constituent of lithosphere, it forms about one fifth of the earth surface. 10.1.2 Lithosphere:

The upper layer of the earth’s crust is called lithosphere.

It is made up of soil, minerals, rocks, organic as well as inorganic matter and to some extent air and water.

The living organisms, plant and vegetation are supported by the lithosphere.

Lithosphere plays an important role as it not only produces food for human beings and

animals, but also the decomposition of organic water is carried out by a host of

microorganisms in the soil.

Increasing human population has put a great pressure on these natural resources which is not available in unlimited quantity.

Vast tracts of land have been cleared of the natural vegetation for cultivation of crops and

for plantations – bringing more and more land under the plough for the increasing human

population, without applying sound ecological principles for the use of land in a profitable

manner.

If managed efficiently, this natural resource has long term sustainable potential for food production.

10.2 Land pollution

Soil or natural layer on the surface of the earth, consisting of clay, silt, sand and gravel.

It is the environment for plant root system and soil organisms. It provides water and mineral salts to plants.

Soil or land supports the life on the earth as it provides us with water, food and shelter. It is essential medium for development of agriculture, forestry, vegetation etc.

Land is major constituent of lithosphere, forming about 1/5th

of the earth’s surface.

This natural gift of land is under threat from various activities like agriculture, industry and

transportation, which produce a large amount of waste and various types of pollutants.

Land pollution or Soil pollution may be defined as the addition of substances to the soil

which adversely affects physical, chemical or biological properties of soil, reducing its

fertility and productivity. Land pollution is the degradation or contamination of the land surface of the earth.


83

Land pollution damage the terrestrial organisms, reduce the uses of the land by man for

agricultural, residential, recreational or other purposes and increase the risk of health

hazards.

10.3 Land use: Most human or natural activities need space for their location and development. This space is provided by land. Various uses of land are: Food production activities (agriculture) Houses the living species, the water resources and raw material resources (mineral and ores etc) Industrial purposes - to install different type of industries Residential purposes - to build different types of domestic buildings Commercial purposes - to build commercial centers Transportation purposes – construction of roads, railway lines, airports, etc. Construction and irrigation structures – dams and canals Energy purposes – Thermal power stations Waste disposal – Disposal of solid and liquid wastes Though the pattern of land use varies from country to country; broadly, thr pattern of land use on earth is :

Agricultural land 11%

Pastures and meadows 22%

Forest land 30%

Urban and non agricultural land 37% In India, more than two-fifth land is agricultural land. The pattern of land distribution in India is as under:

Agricultural land 43.6%

Permanent pastures and meadows 14.6%

Cultural waste lands 12.2%

Forests 10.7%

Barren and inculturable land 8.4%

Urban land 5.3%

No information available 5.2%

10.4 Land Degradation and its causes: The deterioration in the quantity of land and reduction in its fertility and productivity is called land degradation.


84

The factors causing land degradation are: 1. Soil erosion 2. Shifting cultivation 3. Soil pollution 4. Decertification 5. Salination and water logging 6. Urbanisation 1. Soil erosion: Loss or removal of the superficial layer of the soil by the action of water, wind or by the activities of man is termed as soil-erosion. Factor affecting soil erosion are:

I. Amount, intensity and distribution of rainfall: Very high rainfall in short duration and intensive rainfall causes more soil erosion.

II. Slop of the ground: The ground with steep slope causes more soil erosion.

III. Nature of soil: Soil erosion will be more in case of loose soil than dense and heavier soils.

IV. Vegetation cover: Vegetation cover reduce the run off and prevent soil erosion.

V. Soil mismanagement:

Faulty methods of surface irrigation, over grazing, wrong methods of cultivation (Cutting fields along the direction of hill slopes), forest fires etc.

2. Soil pollution:

Soil pollution may be defined as the addition of substances to the soil which adversely affect

physical, chemical and biological properties of soil, reducing its fertility and productivity.

Soil pollution is the reduction in the productivity of soil due to the presence of soil pollutants.

Soil pollutants include pesticides, fertilizers, organic manure, chemicals, radio active wastes,

discarded food, clothes leather goods, plastic paper, bottles, tin cans biomedical waste etc. Common causes of soil pollution are: 1. Disposal of domestic wastes 2. Disposal of agricultural wastes 3. Disposal of industrial wastes 4. Use of pesticides for protecting crops 5. Use of chemical and biological fertilizers 6. Disposal of radioactive and nuclear wastes 7. Disposal of biomedical wastes 8. Intrusion of sea water 9. Oil leakage from storage tanks, pipe line Effects of soil pollution:


85

Soil pollutants have an adverse effect on the physical, chemical and biological properties of the soil and reduce its productivity or fertility.

Pesticides, fungicides and some metallic elements like Cu, Hg, Pb, As, etc are very harmful to

the beneficial micro organisms in the soil as they affect the soil fertility.

The excessive use of fertilizers makes the soil either too acidic or too alkaline making it unfit for crop growth.

Soil pollutants can also clog the pores in the soil due to which air circulation is not possible, so

the micro organism in the soil which are beneficial for growth of plants cannot get enough

oxygen for there survival. This results in decrease in productivity of the soil. 3. Salination and water logging Increase in the concentration of soluble salts in the soil is called Salination. It adversely effects soil

productivity and degrades the quality of land. Salination is caused by a number of processes.

2. Due to poor drainage, salts from irrigation and flood water will accumulate on the soil surface The salts from the lower layers move up by capillary action in summer and deposited on the surface.

3. In coastal regions, winds bring lot of salt from raw water to land, thus causing Salination of

the soil.

4. Excessive use of alkaline fertilizers such as sodium nitrate may cause salinationof the soil. 4. Shifting cultivation:

In shifting cultivation, selected portions of the forest are cut and burnt. Crops are cultivated

on that land for some years till it becomes sterile. Then fresh fields are formed for crop

cultivation.

This practice has led to complete destruction of forests in mainly hilly areas of India and caused soil erosion and problems that accompany soil erosion.

5. Desertification:

Wind causes the shifting of sand dunes from one place to another, increasing the

proportion of fertile land getting converted into deserts each year excessive grazing by

livestock is another factor resulting in desertification.

The destruction of natural vegetation results in accelerated soil erosion due to the removal

of the vegetation cover. Erosion of the top fertile soil results in loss of soil productivity and

formation of deserts.

The immediate cause is the removal of vegetation. Unprotected, dry soil surfaces then blow

away with the wind or are washed away by flash floods, leaving infertile lower soil layers.

All the factors causing soil erosion leads to deforestation, the main factors being over cultivation, over grazing and deforestation.

6. Urbanisation:

Due to urbanisation, people are moving from the villages to towns and cities. Therefore,

cities are expanding rapidly converting fertile productive land into infertile land.


86

10.5 Noise pollution:

Sound is a physical phenomenon that stimulates the sense of hearing, in human beings

hearing takes place whenever vibration of frequencies between about 15 to 20,000 hertz

reach the inner ear. Noise pollution can be defined as unpleasant and unwanted sound.

Noise may be defined as any sound that can produce an undesirable effect to living

especially human either physiologically or may interfere with personal, social or group

activities or work or communication or rest or recreation or sleep. Noise is measured by sound level meter.

10.5.1 Unit of Measurement: Sound powers:

It is the wound energy transferred per second from the sources (sound) to the air. Power is expressed in watts (W).

Sound Power Level Lw: Sound power in watts converted to decibel scale is called the sound power level.

Sound pressure: It is the amount of air pressure fluctuation created by the source of the sound. Sound pressure is expressed as Pascal. A healthy young person can hear sound

pressure is low pressures as low as 0.00002Pa. Sound Pressure Level (SPL):

Sound pressure converted to the decibel scale is called sound pressure level.

Decibel (dB) is used in environmental noise pollution as a measure of sound power level, sound intensity level and sound pressure level.

It is a ratio expressed on a logarithmic scale. This logarithmic scale takes care of wide

range of sound power, intensity and pressure.

dB = 10* log (A/A0)

In general, dB of the quantity A, relative to the reference quantity A0 is defined as above.

Area Code Category of Area Limits in dB

Day time Night time

A Industrial area 75 70

B Commercial area 65 55

C Residential area 55 45

D Silence zone 50 40

Table : Ambient Noise standards

Day time : 6 am to 9 pm Night time 9 pm to 6 am


87

Noise rating system:

A noise may consist of different type of sound with different pressure levels operating for different time intervals.

The frequency of this sound may very. The combined resultant impact of different

sound pressure lasting different periods is worked out by using some statistical measures as

LN and Leq system.

The LN concept:

The parameter LN is a statistical measure indicating how frequently a particular sound

level is exceeded.

The value of LN will represent the sound pressure level that will exceed for N% of the gauging time.

The Leq concept:

Leqis defined as the constant noise level, which over a given time, expands the same

amount of energy, as is expanded by fluctuating levels over the same time. 10.5.2 Sources of Noise Pollution Following are the main sources of noise pollution

1. Traffic sources 2. Industrial sources 3. Constructional sources 4. Other miscellaneous sources

1. Traffic sources: Noise created by various means of transport like trucks, tractors, buses, trains, aeroplanes, etc are the traffic related source of noise pollution. It may be in the form of:

Horn of vehicles Raise of accelerator Vehicle with damaged silencer Noise produced by a diesel car will be more than that produced by a petrol car. A jet aircraft will produce more noise than a propeller type of aircraft.

2. Industrial sources Noise is the essential by product of industry, its intensity and nature being dependent upon the type of industry. Industrial noises are usually produced by:

Reciprocating or rotating machinery Cutting of materials, grinding Blow hammers Generators High pressure and high velocity gases, etc

3. Constructional sources


88

Noises produced by various constructional activities are: Rock crusher for production of aggregate Pile driving equipment Boring and drilling equipment Road rollers Materials handling by conveyers

Rock blasting 4. Other miscellaneous sources

In residential area – loud voice of T.V., music systems, radio, etc Public address system – public functions, Navratry festival etc. Sirens – Police van, industries, ambulance

Military sources – noise of bomb, grenade explosion, tanks other vehicles, missiles etc. Use of crackers during Diwali and other celebrations. Shouting of hawkers at market places Playing of children at play ground.

10.5.3 Noise pollution effects: Major effects:

1. Loss of hearing 2. Annoyance 3. Health effects 4. Interference with communication 5. Working efficiency

1. Loss of hearing:

Loss of hearing occur due to exposure of noise, which is termed as artificial hearing loss. This loss is divided into two types:

A. Noise Induced Temporary Threshold Shifts (NITTS):

This is caused due to exposure to loud noise like bursting of crackers. This can be recovered in a short period of time.

B. Noise Induced Permanent Threshold Shifts (NIPTS): This occurs because of exposure to loud noise for a long period of time.

2. Annoyance:

This is a subjective matter for a noise. Someone may like classical music, it may annoy other.

General annoyance is felt at about 75 to 85 db. Blood vessels get constricted, breathing rate is affected and musical tension changes.

3. Health effects: (i) Effects on physical health: Auditory effects and Non auditory effects A. Auditory effects:

They are grouped into short time and long time effects.

Acoustic trauma is caused by a very high intensity impulsive noise of about 150 db or


89

more from explosion. B. Non – auditory effects: Exposure to a loud noise may increase the pulse rate and blood pressure changes.

Body experiences fear reactions. Disturbed brain waves lead to the interference in vision.

(ii) Effects on mental health: Effect on mental health is less.

Lack of concentration at high noise level and mental disorientation are some of the effects on mental health. 4. Interference with communication:

A person may face the problem of trying to understand another person talking to him/her in an environment with high background noise level.

Background noise level can thus affect the efficiency of offices, school and other places

where communication is of vital importance. External sounds can also interfere with conversation and use of telephone.

5. Working efficiency:

It is found to be decreased drastically whenever a person is working in the noisy environment.

Experiments indicate that irregular bursts of noise are more disruptive than steady noises.

Other effect: 1. Sleep interference 2. Increased industrial accidents 3. Personal comfort interference 4. Property value degradation 5. Effects on wildlife

Control of Noise Pollution: 1. Proper maintenance and lubrication of machine can reduce noise.

2. Sources of noise pollution like heavy vehicles, airports, noise producing industries etc

should be located away from populated areas.

3. Silence zones should be created around residential areas, educational institutions and hospitals.

4. Noisy machines should be installed in sound proof chamber. 5. Planting more trees having broad leaves which can absorb sound.

6. Use of loud-speakers and amplifiers should be restricted to a fixed intensity and fixed hours

of the day.

7. Occupational exposure to noise can be reduced by using protective devices such as ear plugs.

Restricting the unnecessary horn blowing by laws.

10.6 Thermal pollution Thermal pollution


90

Thermal pollution refers to the degradation of water quality as a result of any process that changes the ambient water temperature.

A common cause of thermal pollution is the use of water as a coolant bypower plants

(thermal and nuclear) and industries.

The water used as a coolant is returned to the water sources like rivers, lake etc at a higher temperature.

Power plants for example, discharge heated water, which isat least 15°C higher than the

normal water into a water body.

10.6.1 Causes or sources of Thermal Pollution The various causes of thermal pollution are as follows:

1. Nuclear power plants :

Nuclear power plants emit large amount of unutilized heat and traces of toxic radioactive substances in to the nearby streams.

Effluents form the nuclear reactors and processing installationsare also responsible for

increasing the temperature of waterbodies. 2. Coal fired power plants :

Some thermal power plants use coal as fuel. Coal-fired powerplants constitute the major

source of the thermal pollution. 3. Industrial effluents :

Industries like steel industry uses water for cooling which whendispose in water bodies

causes thermal pollution.

Industriesgenerating its own electricity also requires large amount ofcooling water for heat removal.

Other industries like textile,paper and pulp and sugar industry release heat in water, but

to a lesser extent. 4. Domestic waste water(Sewage) :

Sewage is often discharged into rivers, lakes or streams withoutany treatment. The

sewage normally has a higher temperaturethan the receiving water. 5. Hydro electric power :

Generation of hydro electric power results in negative thermalloading of water bodies.

10.6.2 Effects of Thermal Pollution

Many organisms are killed intently by the hot water and disturb the river ecosystem.

Warm water holds less oxygen than cold water and affect the river’s flora and fauna.

With the increase in temperature of the receiving water the dissolved oxygen (DO)

content decreases and the demand of oxygen increases and anaerobic conditions occur. The egg of fish may hatch early or fail to hatch at all.

It may change the diurnal and seasonal behavior and metabolic response of organisms.

It may lead to unplanned migration of aquatic animals.


91

Rise in temperate of atmosphere may lead to global warming and melting of polar ice caps.

10.6.3 Control Measures of Thermal pollution Control of thermal pollution is necessary as it has adverse effects on aquatic ecosystem. Thermal pollution can be controlled by passing thewater through

1. Large shallow cooling pond: water enters in to the pond formone end. As large surface area

of water is exposed toatmosphere, there is dissipation of the heat and the coolerwater is

removed from the other end.

2. By using cooling towers: The heat is dissipated into the air andwater can be discharged into the river or pimped back to theplant to be reused for cooling.

3. By using spray ponds. The disadvantage of all the methods is that lot of water is lost in evaporation.

10.6.4 Role of individual in prevention of pollution There are lots of environmental problems caused by human actions on the environment. We must

recognizethat each of us is individually responsible for quality of the environment we live in. Our

personal actions worsen or improve the quality of the our environment. Several people feels that

environmental problems can be solved with quick technological solution. While most individuals

wants cleaner environment, not many of them want to make the changes in their lifestyle that

would contribute to the cleaner environment. Each individual should change his or her life style in such a way as to reduce environmental pollution. It can be done by following some of the following suggestions.

Develop respect for all forms of life. Help more in pollution prevention than pollution control. Plant more trees and take care of them. They reduce air pollution. Use eco friendly products. Reduce your dependency on fossil fuel especially coal or oil.

Try to avoid asking plastic bags when you buy vegetables glossary, instead use of cloth bags. Avoid buying the components/things containing CFC as it destroys ozone layer. Save electricity by not wasting it. Adopt popularize renewable sources. Reduce the use of wood and paper products. Promote reuse and recycling wherever possible and reduce production of waste. Use pesticides only when absolutely necessary and that too in right amount. Use rechargeable batteries. Rechargeable batteries will reduce metal pollution. Use organic manure instead of commercial inorganic fertilizers.

Do not put pesticides, paints solvents oils or other harmful chemicals into the drain or

ground water.

Use only the minimum required amount of water for various activities. This will prevent fresh water from pollution.


92

11 ENERGY RESOURCES Energy can be defined as the capacity to do work. Work such as pushing or pulling product of force. Thus, energy is an abstract concept. though energy is present in a number of forms like mechanical, thermal, chemical, biological, which differ basically from one another but together constitute the physical reality of our universe. We cannot see it or feel it, even if we have to pay for it. It is an important factor in the development of an economy. The demand for energy has increased with the economic development of world. In India, the per capita energy consumption is only 221 kg of oil equivalent/year, a very low rate compared with other countries. But now due to the population growth energy consumption will increase day by day.


93

11.1 Conventional energy sources and its problem These include fossil fuels e.g. coal, petroleum and1 natural Gas andnuclear gas, and nuclear energy these are the resources which are exhaustible and cannot be replaced once they are used. These are available in limited quantity and are of greatest-practical significance. These include fossil fuels nuclear energy and all of which are mixtures of compounds containing carbon and hydrogen. Advantages: Available in highly concentrated form'

Easy to store Reliable supply.

Lower cost per unit of energy produced as the technology is matured

Disadvantages:

Limited supply and will one day get exhausted.

Highly polluting. For example : coal based power plant emits large amount of gaseous pollutant like

(SO2, NO2, CO2) and large amount of fly ash which causes many health problems as well as

environmental problems.

Available only in few places. (Non-uniform Oil distribution) for example India has to import 70% of its crude oil requirement which increases import bills.

High running cost.

Extraction of fossil fuels causes various pollution. (In mining operation dust, exhaust of equipment etc. cause air pollution Run off from mines contains many toxic elements which cause water pollution.

11.2 Environmental impacts of a coal based thermal power plant Coal based power plants are the major source of air pollution and also a source for thermal pollution. Coal based thermal plants are major contributors of greenhouse gases and also pollutants responsible foracid rain. Also fly ash emitted from them cause many environmental and health problems Emission from thermal power plants: The main emissions from combustion of coal at thermal power plants are carbon dioxide (CO2),

oxides of nitrogen (NOx, Sulphur dioxide(so2) particulate matter mainly fly ash and also traces of

radioactive elements Power plants are the major contributor of CO2 which is a major greenhouse


94

gas responsible for global warming. CO2 emitted from power plants contribute almost 41% of the US man-made CO2 emissions.

Coal contains Sulphur so combustion of coal will emit large amount of SO2 which is largely

responsible for acid rain and other health problems. Use of coal having lower sulphur content can

reduce so2 emissions. Also washing of coal reduce the emission another major problem related to

coal combustion is the emission of particulates that have a serious impact on public health. Particulate matter can irritate small airways in the lungs, which can lead to increased problems like asthma, chronic bronchitis, and airway obstruction.

The dominant form of particulate matter from coal fired plants is coal fly Ash, but secondary sulfate and nitrate also comprise a major portion of the particulate matter. Coal fly ash is what remains after the coal has been combusted, so it consists of the incombustible mostly inorganic Matter found in the coal.

As most of the ores in the Earth's crust, coal also contains low levels Of uranium, thorium and other naturally occurring radioactive isotopes Whose release in to environment leads to radioactive contamination. These elements are present as very small trace impurities in coal, but Amount of coal burned in a power plant is very high. A 1000 MW coal Based power plant could release as much as 5.2 tons/year of uranium (containing 34 kg of uranium-23S) and 12.8 tons/year of thorium Power plants utilize only 1/3 of the energy provided by fossil fuels For their operation. Remaining 2/3 is generally lost in the form of heat to The water used for cooling. So the water which is discharged from the Power plants in to the water bodies have L0-16"C higher temperature Than the receiving waters which leads to thermal pollution. This thermal pollution causes reduction in dissolved oxygen which Effects of the aquatic animals. Also the heat sensitive organisms will die.Also mining of coal will cause large scale air, water, land, and noise pollution.

11.3 Environmental impacts of nuclear power plant Nuclear power plants generate large amount of deadly nuclear radioactive waste. The low level waste must be stored safely for 100-500 years, while the high level waste remains radioactive for very long period, roughly 240,000 years. There is no satisfactory way of storing the waste.

Nuclear waste is piling up and if not stored properly it is a potential cause of great disaster as radiations emitted by this waste can cause many problems to mankind.

All organisms are affected from the radiation or radioactive pollution, and the effects are extremely dangerous. The effects may be somatic (individual exposed is affected) or genetic (future generations) damage. The effects are cancer (bone, thyroid, breast, lung and skin), shortening of life span, mutations in the DNA, miscarriages, eye cataract etc.


95

Nuclear power plants have created many contaminated sites, particularly in US and former USSR. The cost of cleaning them up will run in millions of dollars.

The biggest problem is about the safety of the nuclear power plants.

Chernobyl nuclear accident is the worst nuclear disaster in the history.It occurred on 26 April 1986.

Accident accrued due to faulty shutdown. The radioactive debris and gases drifted over most of the northern hemisphere. On the first day of accident 31 persons died and 239 were hospitalized. Since the plume was rich in Iodine-l31, Cesium 134 and cesium 137 it was feared that some 5,75,000 people exposed to radiation would suffered from ulcerating skin, loss of hair, nausea and anemia.

Agricultural products were damaged for years and flora and fauna was destroyed.

The nuclear energy is cheap, inexhaustible and nonpolluting source of energy but in absence of proper care and caution disasters like Chernobyl can rock the society.

Nuclear power plants also cause thermal pollution causing damage to the aquatic life. Mining of uranium and other radioactive elements also cause some radioactive pollution.

11.4 Non-conventionalenergysource-advantages and disadvantages These include solar, wind, geothermal, tidal, biomass and hydrogen energy. these are those natural resources which are inexhaustible and can be used to produce energy again and again. These are available in unlimited amount in nature and develop in a relatively short period of time. Advantages:

Wide availability

Lower running cost

Decentralized power production

Low pollution

Available for the foreseeable future. Disadvantages:

Unreliable supply

Very difficult to store

Usually produce in small quantities


96

Currently per unit cost of energy is more compared to other type.

Non-conventional energy source include

Hydropower

Solar energy

Wind energy

Geothermal energy

Tidal energy

Biomass energy

Hydrogen energy & fuel cells

11.4.1 1. Hydropower Hydel energy is the cheapest, neat and clean source ofHarnessed by human civilizations since its earlier days in the formWater wheels. A hydroelectric power plant harnesses power from water Flowing under pressure (i.e. water falling from height). Electric Generator driven by water turbines represent. The use of hydel energy asElectricity. Potential energy is first converted in to mechanical energy by Turbines which are coupled with generator to produce electricity. Advantages of hydropower over the other sources of power.

Longer life

Minimum operating stall

Can be started very quickly and stopped also

Saves scarce fuel reserves.

Nonpolluting and hence environmental friendly.

Low cost of generation and maintenance.

storage based hydro schemes provide benefits of irrigation,

Drinking water supply, navigation, recreation etc.


97

Problems which affect the hydropower generation in India.

Land Acquisition: Land acquisition is the major problem as construction of dam causes large submergence of land. Many political,regional and social hurdles comes in the. process of land acquisition. Environmental Aspects: It accounts for the main bottleneck inproject approvals. It takes 2 to 5 years to get forest and Environmentclearance. Rehabilitation: Rehabilitation and resettlement of displacedpeople is a major problem associated to any hydropower project. Seismic activity: Weight of the stored water behind the demandincrease the seismic activity in the area. Increase in seismic activitycan cause damage to the dam itself and can unleash large scale floods. Initial investment: Requires large scale initial investment. Other problems are: Lack of Motivation. Non-availability of sophisticated equipment. Labor problems, delays in supplies and,Disputes over the contractual costs create several hindrances

11.4.2 2. Solar energy Energy comes to the earth from the sun. This energy keeps r temperature of the earth above that in the colder space. Causes current atmosphere and in ocean, causes the water cycle and general photosynthesis in plants. Solar energy can be a major source of power. Its potential is 179 billion mw which is about 20,000times world’s demand. But so far it could not be developed on a large scale.sun’s energy can be utilized as thermal and photovoltaic. Applications:

Solar water heating.

Solar drying of agricultural and animal products.

Solar distillation.

Solar cookers.

Solar engines for water pumping.


98

Solar furnaces.

Solar photovoltaic cells.

Solar heating of buildings.

Solar green houses.

Advantages:

Easy installation and maintenance

Absence of noise and other form of pollution

Solar photovoltaic cell system are favorable for fulfilling the requirement of electricity for decentralized applications.

Long life of SPV systems make them favorable for use in remote and isolated areas, forest, hilly and desert regions.

Limitations:

Uncertainty of availability of solar energy due to clouds, wind rainfall etc

Large spaces are required for the collection of solar energy at useful rate.

Amount of sunlight that arrives at the earth’s surface is not constant. It depends on location, time of day, time of year and weather conditions.

Currently the initial cost is higher but is reducing at a faster rate.

11.4.3 3. Wind energy Wind, which is essentially air in motion, has kinetic energy by virtue the movement of large masses of air caused by differential heating of the atmosphere by the sun. At any given time, the-amount of energy contained in the wind is proportional to the wind speed at that instant in the context of wind based energy production systems. This energy can be utilized for performing mechanical and electrical works. Wind turbines can be used to generate electricity, for lifting water from wells, for direct water pumping and many more. Types of wind mills:


99

1.Multiblade type wind mill 2.Sail type wind mill 3.Propeller type wind mill 4.Savonius type wind mill 5.Darrieus type wind mill Advantages of wind mills:

Nonpolluting and environment friendly source of energy

Important renewable and sustainable source of energy,

available free of cost.

Generation period is low.

Cheaper

Easily available in many off-shore, on-shore and remote areas

Limitations:

Low energy density

Favorable in geographic locations which_ are away from cities.

Variable, unsteady, irregular, intermittent, erratic and dangerous

Wind turbine design, manufacture and installation have proved to be complex due to widely varying atmospheric conditions.

Located only in vast open areas

Continuous whirling and whistling can be irritating.

Economical only on a small scale

11.4.4 4. Geothermal energy: Geothermal energy is the energy which lies embedded within the earth's crust. There is an increase in temperature of the earth with increasing depth below the surface. All the heat stored in the earth's crust and thermal energy constitutes inexhaustible source of energy termed as geothermal energy. Two main uses of geotherr4al energy are: 1. Geothermal power plants are generally built where geothermal reservoirs are located within a mile or two of the surface.


100

2. Geothermal heat pumps use stable ground or water temperaturenear the earth's surface to control building temperatures above ground. Advantages:

Most versatile

Least polluting source

Inexpensive

Provide steady base load power with very low variable

High power generation than for solar and wind

Limitations:

Overall efficiency for power production is quite low (15%) as compared to fossil fuels (35 to 4O %). Air pollution results in case of release of gases present in steam and hot water coming out of the geothermal resource discharged into surface water bodies may be ecologically hazardous.

Drilling operations at sites cause noise pollution.

5.tidal energy: Tides are formed due to the gravitational effect of the sun and moon on the earth. The gravitational force causes a periodic rise and fall of water level of sea in rhythm with the daily rhythm of the rising and setting of sun and moon. This periodic rise and fall, called a tide, can be used to produce electric power which in this case is known as tidal power.

Tidal energy has great potential in areas like the Gulf of Kutch in Gujarat, gulf of Cambay and Sunder ban area of West Bengal where In height of the tide is sufficient for construction and economical functioning of tidal power plant.

The tidal energy can be harnessed by constructing a tidal barrage.

During the high tide, the sea water flows into the reservoir of the barrage this turns the turbine to produce electricity.

Under the low tide water from the reservoir flows back into the sea and turns the turbine to generate electricity.

11.4.6 6. Biomass energy:


101

Biomass, defined as living matter or its residues. It includes all the new plant growth, residues and wastes, algae, agricultural and forest residues, wastes, biodegradable organic effluents from industries like sugar, slaughter house, meat packing plants, distilleries etc.

Biomass resources fall into three categories:

Biomass in its traditional solid mass (wood and agricultural residue)

Biomass in nontraditional form (converted to liquid fuels).

To ferment the biomass anaerobically to obtain a gaseous fuel called bio gas. Sources of Biogas:

Sewage

Crop residue

Vegetable residue

Water hyacinth

Poultry droppings

Algae

Ocean keep

Cattle waste.

Advantages:

Plants ensure a continuous supply of energy due to their continuous growth.

Potential for rural areas

Biogas can be used for cooking purpose.

For operating small engines for pumping water

Wastes can be used as an excellent fertilizer Limitation of Biomass energy is except biogas production, the other biomass energy sources have to be establishing a significant role.

11.4.7 7. Hydrogen energy and Fuel cells:


102

One of the most important features of hydrogen energy is that it canbe produced from water which is available in nature. It has the highest energy content per unit mass than any chemical fuel. It can be substituted for hydrocarbons in a broad range of applications, often with increased combustion efficiency. It is non-polluting and can be used in fuel cells to produce electricity and heat. Fuel cell: It operates like a battery. A fuel cell requires no recharging. It will produce energy in the form of electricity and heat. It is an electrochemical Conservation device that converts hydrogen and oxygen into water, producing electricity and heat in the process. Advantages:

Less pollution, low noise so it is acceptable to residential areas.

High operating efficiency as it does not involve a thermal Process.

Unit is lighter smaller and needs less maintenance.

Limitations:

Low voltage

High initial cost

Low service life

11.5 Problems due to over use of energy resources Due to population explosion, rapid industrialization and most importantly man's unending desire to increase his comfort levels and living standards, the utilization rate of all the energy resources0 like coal, crude oil, metals etc. is increasing by leaps and bound. This over utilization can cause some serious environmental, technological, economic and ecological problems. Following are the some of the important problems which will arise due to Over use of energy resources: Extinction of resources: It has been predicted that many of the nonrenewable resources like coal- crude oil etc. will be completely depleted or become extinct in the next 35-40 years as they are in limited quantity and takes centuries to get replenished.


103

Excessive mining of minerals and associated problems: Due to over use of minerals more and more explorations and mining of minerals is taking place. Mining operations causes lots of problems like;

Dusting during loading and unloading of minerals, blasting, vehicular movement etc

Equipment used for it as well Blasting causes lot of noise pollution

Runoff from the mines contains lot of heavy metal and toxic substance which cause water pollution in the receiving water body (surface as well ground water).

Causes large scale deforestation

Causes large scale land degradation

Exhaust emitted from different machinery/equipment used in mining operation causes air pollution It causes displacement of the people living in that area.

Dereliction (closing or abandoning mines) causes many harmful effects like waste of agricultural land, health and accident hazards as land over underground mines may subsides, causing house to collapse or creating hummocky ground unsuitable for any use and often full of pools of polluted water. Also old quarries and open cast pits may be dangerous.

3.Pollution: Over use of energy resources results in lot of emission of CO2.SO2, NOx particulate

matter (fly ash, smoke, etc.) which cause air pollution and related problems like acid rains, global warming etc.

Economical Effect: As these resources will get depleted, cost will increase which will seriously effects the economy and the development of the nation as large funds will be diverted for importing the fuels and also for the exploration of new possible sources. Also as the levels of these resources will decrease, its extraction will become more and more costly. Need for development of new technology for the use of alternative fuels : The machineries and vehicles which are using conventional resources will become obsolete as their will be no fuel to run them, so new technologies has to be developed using which alternative fuels can be using for running vehicles and equipment. It is very difficult to imagine life without energy resources, we have to use it; but if we do not use it judiciously and do not start conserving them and also if proper stress &is not laid on the development of alternative sources of energy, time will come when everything will come to a standstill.


104

12 12. GLOBAL ENVIRONMENTAL ISSUE

12.1 Introduction: There are significant changes in the global ecosystem after the World War II. The man made forces disrupting the global ecosystem can be enlisted as under: Population explosion Rapid industrialization Urbanisation Modern life style The increased population has enhanced demands for food, shelter and natural resources. Increased human activities for rapid industrial growth result in more and more consumption of resources and damage to ecosystem by environmental pollution. Rapid and unplanned industrial growth has created increased demand of natural resources water and energy especially fossil fuels. All these factor are collectively cause following global environment problems like Acid Rain Global warming due to green house gases Ozone depletion

12.2 Acid rain When the pH of rain water is less than 5.6 it is called as acid rain.

The natural rain water has pH of 5.6 at 20°C due to formation of carbonic acid due to dissolution of

CO2 in water.

CO2 + H2O H2CO3

Oxygen, nitrogen and sulphur originating from industrial operation and fossil fuel combustion are the major causes of acid rain formation.

2SO2 + 02 2SO3

SO3 + H2O H2SO4

2NO + O2 2NO2

4NO2 + 2H2O + O2 4HNO3

Sulphuric acid and Nitric acid are the major acid found in the rain water. The proportion of Sulphuric acid ranges from 60 to 70% and that of Nitric acid is 30 to 40%.


105

In the absence of rain, dry, deposition of acid may occur. Acid forming gases like oxides of sulphur and nitrogen and acid aerosols get deposited on the surface of water bodies, vegetation, soil and other materials. Causes of Acid rain:

SO2 and NOx are mainly responsible for forming of acid rain. Main sources of this pollutant

are:

Fossil fuel based power plants

Smelting of sulfide ore

Automobiles exhaust

Industrial plant using sulphuric acid and nitric acid. Environmental effects of acid rain:

Effects on building material:

Acid rain will cause damage to common building materials (such as lime stone and

marble), statues monuments.

CaCO3 + 2H+

Ca2+

+ CO2 + H2O

Many metals get oxidized. Iron corrodes with the presence of acid rain to form rust. The cost of maintenance of iron structures is high in highly polluted areas.

Fe +2H + Fe

2+ + H2

Effects on Aquatic life:

Aquatic life especially fish are badly affected by lake acidification.

Acid rain mobilizes heavy metals such as calcium and mercury in soils, rock and sediments, which are then leached out by rain and enter the surface water.

Acidified lakes have high levels of cadmium, lead, aluminum, manganese, zinc,

copper and nickel. All these can kill living organisms if present in sufficient quantities. It disturbs the food chain of aquatic ecosystem.

Effects on fertility of soil:

Due to high solubility of acidic rain water, plant nutrients like nitrogen, phosphorous and potassium gets leached away, which reduces fertility of soil.

It damages foliage and weakens trees.

It also make atmospheric hazy.


106

Control of Acid Rain:

Emission of SO2 and NO2 from industries and power plants should be reduced by using pollution

control equipments.

Liming of lakes and soils should be done to correct the adverse effects of acid rain.

12.3 Ozone depletion:

A layer of ozone (O3) is present in the stratosphere 2O-25 km above the surface of earth. This layer

filters out harmful ultraviolet radiation from the sunlight, thus protects various life form on the earth. It acts like a natural sunscreen for the earth. Formation of ozone layer: In the stratosphere ozone is continuously created by the following reaction.

O2+ hv O + O

An ultraviolet ray decomposes oxygen in to atomic oxygen by photolytic decomposition.

The atomic oxygen thus farmed rapidly reacts with molecular oxygen to form ozone.

O + O2 + M O3 + M

(M is a third body necessary to carry away the energy released in the reaction). Ozone thus formed distributes itself in the stratosphere and absorb harmful ultraviolet radiation (200-320 nm) and it continuously converted back to molecular oxygen.

O3+ hv O2 + O The net result of above reactions is an equilibrium concentration of ozone. Destruction of Ozone: The destruction is mostly caused by chlorofluoro-carbon (CFC).

CCl3F uv CCl2F + Cl ………….(1)

CCl2F 2 uv CClF2 + Cl ………….(2)

CI + O3 CIO + O2 ………….(3)

CIO + O CI + O2 ………….(4)

Chlorofluorocarbon (CFC): CFC is a combination of carbon, hydrogen, fluorine and chlorine.CFC-11 and CFC-L2 are the most commonly used CFCs. Use of CFC: Used as coolants in refrigerators and air conditioners.


107

Propellants.

Cleaning solvents

Stuffing of mattresses.

CFCs released in the troposphere reach the stratosphere and remains there for 65-110 years

destroying O3 molecules.

Ozone - depleting potential (ODP) is the ratio of the impact on-ozone caused by a chemical compared to the impact of a similar mass of CFC- 11. The ODP of CFC-11 is 1.0.

Nitrous oxide emitted by supersonic aircrafts, during combustion of fossil fuel, by action of bacteria and use of nitrogen fertilizers also breaks ozone molecules.

The ozone hole is formed each year when there is a sharp decline in the total ozone over most of Antarctica during southern hemisphere spring (September and October).

Effects of Ozone Depletion:

Ozone depletion in the stratosphere will result in more UV radiation reaching the earth especially UV-B (290-320 nm). The UV-Radiations affect DNA and the photosynthetic chemicals. Any change in DNA can result in mutation and cancer. Cases of skin cancer which do not cause death but cause disfigurement.

Easy absorption of UV rays by the lens and cornea of eye will result in increase in incidents of cataract.

Phytoplankton’s are sensitive to UV exposure. ozone depletion will result in decrease in their population thereby affecting the population of zooplankton, fish, marine animals, in fact the whole aquatic food chain.

Yield of vital crops like corn, rice, soyabean, cotton, bean, pea and wheat will decrease.

Degradation of paints, plastics and other polymer material willresult in economic loss due to effects of UV radiation resulting from ozone depletion.

12.4 Green House Effect and Global Warming:

A house of glass is used for raising delicate plants and in cold countries. This house is called green house.

A green house has higher temperature inside than outside which is due to

Glass walls

High carbon dioxide content

High water vapour content of the air in the green house.


108

They let short wave radiation (0.15 – 4.0 mm wavelength) to pass through them but prevent the escape of infrared radiation emitted by the earth surface. This make inside house warmer than outside. This effect is called green house effect. Some of the atmospheric gases and air pollutants have the propertysimilar to the glass. The atmospheric gases which are permeable to short wave radiation, but are strong absorber of infrared radiation emitted from the heated earth surface are called as greenhouse gases. Greenhouse gases includes

Carbon dioxide (CO2)

Nitrous oxide (N2O)

Methane (CH4)

Chlorofluoro carbon (CFC)

Among these CO2 is mainly responsible for green house effect. Other gases are more potent

thanCO2, but as their concentration is less, the effect of CO2 is more compared to these gases.

Warming of earth by green house effect is occurring since many centuries, it is only due to this effect that good temperature for living is maintained on the earth surface but now due to large scale pollution resulting from rapid industrialization fossil fuel burning, deforestation etc. this effect has become more severe. Global warming means increase in any temperature of the earth due to green house gases. Green House Gases:

Carbon dioxide (CO2)

Carbon dioxide contribute about 55- 60% to global warming from green house gases produced by human activity.

Industrial countries account for about 76% of annual emissions.


109

The main sources are fossil fuel burning (67%) and deforestation, other forms of land clearing and burning (33%).

Chlorofluoro Carbon (CFC): CFCs are synthetic gaseous compounds of carbon and halogens. CFC contributes about 14-20% of the human contribution to green house gases.

The main sources of CFCs in the atmosphere are leaking air conditioners and refrigeration units, evaporation of industrial solvents ,production of plastic foams and propellants in aerosol spray cans. CFC

Generally trap- 1500 to 7000 times more heat per molecule than CO2.

Methane (CH4):

It contributes about 18-20% to global warming from green house gases produced by human activities

Methane is produced by anaerobic decomposition by bacteria called methanogens. It is produced from garbage dumps, fresh water wet lands, flooded rice field and enteric fermentation in cattle. It is also produced by biomass burning. Atmospheric concentration of methane is1.675 ppm and it is increasing at a rate of 1% annually.

Nitrous Oxide (N2O):

It is responsible for 6% of the human input of green house gases.

The main sources of N2O are agriculture, biomass burning and industrial processes. It is produced by the break down of nitrogen rich fertilizers in the soil and nitrate contaminated ground water, burning of nitrogen rich fuels, live stock waste and during nylon production. Its life span in the troposphere is140-190 years. G.W.P. of Nitrous oxide is 230.

The atmospheric concentration of Nitrous oxide is 0.3 ppm and is increasing at a rate of 0.2% annually.

12.4.1 Impact of Global Warming: Global Temperature increase: It is estimated that average temperature of earth may increase by 1.4°C to 5.8°C by the year 2100

from year 1990. In the 20th

century, the global mean temperature has increased by about 0.6°C.

Rise in sea level:


110

With increasing global temperature polar icecaps and glaciers will melt. It will also cause thermal expansion of seawater resulting in further rise in sea level.

Effect on human health: The global warming will lead to changes in the rainfall pattern in many areas, thereby affecting the distribution of vector – borne dieses like malaria, elephantiasis etc.

Effect on food production: Global warming will reduce crop production due to increased incidence of plant diseases and pests, explosive growths of weeds. It is estimated that the yield of rice along in South East Asia will decrease by 5% for each 1°C rise in temperature. Other climatic effects Unequal distribution of rain which may results in flooding in some areas and drought in some areas.

In temperate regions, the summers will be longer and hotter whereas the winters will be shorter and warmer.

The already dry sub-tropical regions may become drier and the tropical regions may become wetter. Control of Global Warming: Reduction in green house gas emission by reducing the use of fossil fuels and by developing alternative renewable sources of energy like solar energy, wind energy etc.

Reduction in N2O emission by minimizing the use of nitrogen fertilizers in agriculture.

Increase of the vegetation cover, particularly forest as it is sinking for CO2 absorption.

Phasing out chlorofluoro carbon and developing its substitute. Trapping and use of methane as fuel.

Stabilize population growth. Using energy resources judiciously.

12.5 International step for Mitigation Global Change: Montreal Protocol: In 1987, twenty seven, industrialized countries signed an international agreement to protect the ozone layer in stratosphere. This agreement is known as Montreal Protocol. The main points of the agreement are: To limit the production and use of ozone depleting substances.


111

The participating countries agreed to freeze production of CFC at 1986 levels and to reduce production by 50%o by 1999. In 1992 the phase out date for CFCs and halon entirely was moved up to 1996. Helping the developing countries to implement use of alternatives to CFCs.

Up till now, more than 175 countries have signed the Montreal protocol.

Kyoto protocol : An international conference held in Kyoto, Japan in December, 1997, has specified the commitments of different countries to mitigate climate change.

This protocol requires countries to take appropriate measures to reduce their overall greenhouse emission to a level at least 5 per cent below the 1990 level by the commitment period 2008-2012.

Earth summit: The United Nations conference on Environment and Development (UNCED), the Earth-summit, held at Rio de Janeiro, Brazil in 1992, established the principles for reducing greenhouse gas emission.


112

13 CHAPTER: 13 ENVIRONMENTAL ACT AND REGULATIONS:

13.1 Environment Protection Laws in India: Constitution of India has a number of provisions demarcating the responsibility of the central and state/governments towards ‘Environmental Protection’.

The constitution of India makes provisions for Environmental protection on: Fundamental right Directive Principles of State Policy Fundamental Duties

13.1.1 The Water (Prevention and control of pollution) Act, 1974: 1. Objectives of this Act:

Prevention and control of water pollution. Maintaining and restoring the wholesomeness of water.

Establishment of Boards, with a view to carry out the purposes aforesaid for the prevention

and control of water pollution. 2. Definitions of ‘Pollution’ under the Act "Pollution" means such contamination of water or such alteration of the physical, chemical or biological properties of water or such discharge of any sewage or trade effluent or of any other liquid, gaseous or solid substance into water (whether directly or indirectly) as may, or is likely to, create a nuisance or render such water harmful or injurious to public health or safety, or to domestic, commercial, industrial, agricultural or other legitimate uses, or to the life and health of animals or plants or of aquatic organisms. 3. Powers and Functions of Boards: (A) Constitution of Central Board: The central Government shall, with effect from such date as it may, by notification in the official Gazette, appoint, constitute a Central Board to be called the (Central Pollution Control Board) to exercise the powers conferred on and perform the functions assigned to that Board under this Act.

A full time chairman, being a person having special knowledge or practical experience in respect of matters relating to environmental protection or a person having knowledge and experience in administering institutions dealing with the matters aforesaid, to be nominated by the central Government.

Not more than five officials nominated by the central government.

Not more than five persons nominated by the central Government from amongst the members of the state Boards.

Two persons to represent the companies or corporations owned, controlled or managed by

the Central Government, to be, nominated by that Government. (B) Constitution of State Board:

Under Section- 4, of the State pollution Control Board may be constituted having the same constitution as the Central Board.

(C) Function of Central Board:


113

Promote cleanliness of streams and wells in different areas of the States.

Advise the central Government on any matter concerning the prevention and control of water pollution.

Co-ordinate the activities of the State Boards and resolve dispute among them. To lie down, modify or annul, in consultation with the state Government concerned, the standards for a stream or well.

To plan and cause to be executed a nation-wide programmed for the prevention, control or abatement of water pollution.

To establish or recognize a laboratory or laboratories for analysis of water samples from any

stream, well or trade effluents. (D) Function of State Board:

To plan a comprehensive programmed for the prevention, control or abatement of pollution of streams and wells in the state and to secure the execution thereof.

To advise the state Government on any matter concerning the prevention, control or

abatement of water pollution.

To collect and disseminate information rerating to water pollution and the prevention, control.

To inspect sewage or trade effluents.

Prescribing effluent standards for the sewage and trade effluents

To evolve methods of utilization of sewage and suitable trade effluents in agriculture. To evolve efficient methods of disposal of sewage and trade effluents on land.

Establishing and recognizing laboratories for analysis of samples.

(E) Power of the State Government

Power to obtain information

Power to take sample Power of entry and inspection

Power of prohibition on disposal of polluting matter into a stream or well.

(F) Penalties for the Violation of the Act: In case of failure to give information by a person discharging effluents into stream or well or

regarding construction or establishments of a disposal system the penalty is imprisonment up to 3 months or fine up to Rs. 10,000/- or both. If the omission continues, the penalty is an additional fine up to Rs. 5000/- Per day.

In case of permitting pollution material into any stream, well or land the penalty is

imprisonment for one and a half years to six years or fine or both.

13.1.2 Air (prevention and Control of Pollution) Act, 1981 (1) Objectives of the Act:

Prevention, control and abatement of air pollution.

Maintaining the quality of air. Establishments of the Boards for the prevention and control of air pollution.

(2) Definition of Pollution under this Act


114

"Air pollutants” means any solid, liquid or gaseous substance (including noise) present in the atmosphere in such concentration as may be or tend to be injurious to human beings or other living creatures or plants or property or environment. (3) Powers and Functions of Boards: (A) Constitution of Central/state Boards:

To have an integrated approach for tackling the problems related to pollution, this Act provides that the Boards for the prevention and control of water pollution, constituted under section 3 and 4 of the water (prevention and Control of Pollution) Act, 1974, shall also act as Air pollution Control Boards. (B) Functions of Central Boards:

To improve the quality of air and to prevent, control or abate air Pollution in the country.

To plan and execute a nation-wide programme for the prevention, control or abatement of air pollution.

To co-ordinate the activities of the state and resolve disputes among them.

To lay down standards for the quality of air.

To establish or recognize a laboratory or laboratories to enable the Central Board to perform its functions under this section efficiently.

(C) Functions of State Boards: To plan a comprehensive programme for the prevention, control or abatement of air

pollution and to secure the execution thereof.

To advise the State Government on any matter concerning the prevention, control or abatement of air pollution;

To collect and disseminate information relating to air pollution.

To establish or recognize a laboratory or laboratories to enable the State Board to perform its functions under this section efficiently.

(D) Powers of the Board Power to declare air pollution control areas: under section 19.1, the state Govt., after

consultation with the state Board may I. Declare any area or areas as Air Pollution Control Area notification in the official gazette.

II. Prohibit use of any fuel or appliance causing or likely to cause air pollution in an Air pollution control area.

III. Prohibit burning of any material causing or likely to cause pollution in an Air pollution Control Area.

Powers to establish standards for emission of air pollutants from automobiles. (5) Penalties of the Violation of the Act:

Except for the fact that there is no provision for publication of names of offenders under this Act, the penalties for defaulters are same as under the Water Act. The main drawback is that no consent or permission is required to be taken from the Board for establishing an industry outside the Air Pollution control Area even though its emissions may be reach the Air Pollution Control Area also.

13.1.3 Gujarat pollution control board (gpcb)


115

The Government of Gujarat constituted the GPCB (Gujarat Pollution Control Board) on 15.10.1974 as per provisions under the Water (Prevention and Control of Pollution) Act, 1974, with a view to protect the environment, prevent and control the pollution of water in the State of Gujarat. The Board has been entrusted with the central Acts and relevant Rules for pollution control as notified thereof from time to time.

There are thirteen Regional offices, six Regional offices attached with laboratory facilities are located at Vadodara, Bharuch, Surat, Vapi, Itajkot and Jamnagar. Regional offices at Godhra, Mehsana, Ahmedabad and Bhavnagar are yet to be equipped with analytical facilities. Three Regional offices located at Bhuj, Nadiad and Junagadh are under development stages. Objective of GPCB: The major objectives of the Board are centered Control and the protection of the environmental quality.

Bring about all round improvement in the quality of the environment in the state by effective implementation of the laws.

Control of pollution at source to the maximum extent possible with due regard to

technological achievement and economic viability as well as sensitivity of the receiving environment

Identifications of sites and development of procedures and methods for the disposal of

hazardous wastes.

Maximization of re-use and re-cycle of sewage and trade effluent on land for irrigation and for industrial purpose after giving appropriate treatment and thereby economizing and saving on the use of water

Minimization of adverse effect of pollution by selecting suitable locations for the

establishment of new industrial projects.

Co-ordination with other agencies of the State Government and local authorities to encourage the Common Effluent Treatment Plants and Disposal Facilities

close co-ordination with educational institutions, non government organizations, Industries

Associations, Government organizations, etc. to create environmental awareness. Functions of GPCB:

Promotion of cleanliness of wells and streams in different areas of the State. Issuing directives for pollution control measures to the polluting units.

Prevention, control and abatement of air pollution in the State and improvement in the

ambient air quality.

Advising the State Government on any matter concerning prevention and control of water and air pollution.

Approving judicious location of new industries from pollution control point of view. Carrying out monitoring of rivers of the State.

Carrying out monitoring of the major cities of the State

Promotion of re-use and re-cycle of sewage and trade effluent on land for irrigation Developing methods of treatment of effluent and air pollution control equipment.

13.1.4 Gujarat environmental management institute (gemi): Gujarat Government wanted to have an appropriate institute to manage the environmental issues for achieving sustainable development and accordingly constituted Gujarat Environmental


116

Management Institute (GEMI), vide its GR dated 1-2-1999. Giving counsel and guidance to the industrial units of the State for prevention and control of

pollution in consultation with other National and state level Government and Non-Government Institutes and Voluntary Organizations.

Formation of a research and consultation institute committed to the aim of prevention,

control and eradication of pollution.

Study of the use of the solid waste and effluents of industrial units and giving counsel for final disposal of it.

Exploration of ways and means for reuse and recycling of industrial wastes

Review of environmental impacts and study as to its efficacy.

Carrying out environmental audit work and preparation of environmental statements.

13.1.5 Gujarat ecology commission (gec): The Gujarat Ecology Commission, founded in 1992 by Forest and Environment Department, Gujarat with a view on studying and conserving ecologically degrading areas in the state is one of the success stories of the efforts towards the environment. Objectives of Gujarat Ecology Commission are:

To provide an organization that plans and works for restoration of ecologically degraded areas to ensure the ecological health of Gujarat systematically and holistically.

To create institutions and organizations necessary for achieving the objectives of G.E.C.

To undertake on its own or with the support of other agencies, rehabilitation or restoration

of disturbed ecosystems of the State with special emphasis on degraded lands (waste lands) including ravines (kotars) mangroves, water bodies, river systems and degraded forests.

To act .as the State's single umbrella for accreditation of various NGOs eligible for

funding for activities aimed at ecological restoration of degraded ecosystems.

13.1.6 Gujarat institute of desert ecology (guide): To set up an institute for research on arid and semi-arid regions of Gujarat, the Gujarat Ecology commission - GEC signed a Mou with Jacob Blaustein Institute of Desert Research, Israel in September 1993. Mission:

GUIDE will catalyze the process of reducing hardships to human beings in desert ecosystems of Gujarat, following sound ecological principles and carefully using scientific knowledge, imaginative technology and capital. Role:

To focus on desert and arid ecosystems of Gujarat, with special emphasis on Kachchh.

To identify problem areas and evolve appropriate solutions and management strategies, with the help of applied research.

To formulate and implement relevant projects that would provide models for emulation.

13.1.7 Department of environment and forest gujarat: The Forests & Environment Department forms the policy for the conservation of the forest,

protection of the wildlife and the Environment in the State of Gujarat.


117

The Forests & Environment 'Department in the Government of Gujarat has environment wing

and forest wing. The environment wing of the Department is the apex body in the Gujarat State for implementation of all the environment related matters including Environment (Protection) Act, 1986, which is an umbrella Act on environment in the country. Functions of the Forests and Environment Department:

The Department acts, as a secretariat for the Appellate Authority constituted under the water Act 1974, Air Act 1981 and Hazardous waste (Management and Handling) Rules, 1989.

The department implements the coastal Regulation zone (CRZ) Notification and the coast al

zone Management plan in the state. The Department considers the proposals received for environmental clearances under the CRZ notification, 1991.

Under the Environment Impact Assessment Notification, certain categories of industries require mandatory environmental clearance from Government of India. Such applications are recommended by the Department based on the merits of the case.

The Department is implementing the Notification on "use of fly-ash, bottom-ash or pond-ash generated by the coal/ lignite based thermal power plants", in the Gujarat State.

13.1.8 Gujarat state disaster management authority (gsdma) Immediately after the 26

th January 2001 earthquake, Gujarat state Disaster Management Authority

(GSDMA) was established and, registered a s a 'society' under the provisions of the societies

Registration Act and the Bombay Public Trust Act on 8th

February 2001. Objective:

To prepare programmes and plans to mitigate the losses on account of disasters as a strategy for long terms disaster preparedness.

To undertake research and study regarding causes for losses on account of natural disaster

and to suggest remedial measures for minimizing the same

To undertake research and study regarding causes for losses on account of natural disaster and to suggest remedial measures for minimizing the same.

To manage Gujarat Earthquake Rehabilitation and Reconstruction Fund.

To provide to arrange financial assistance So as to achieve the objects of the society.

To do all the acts and things conducive for the attainment of the above objects in the most possible manner, which are relevant to fulfill all the objectives.

13.1.9 Role of Non Government Organizations In Improving Environmental Awareness: Non-governmental organizations (NGOs) , are simply agencies or groups which are different

from government bodies. They are generally characterized by creativity in approach, flexibility in functioning and

innovativeness in methods and technologies. There are more than 10,000 NGO’s in India ranging from National agencies to local groups.

Aims and objectives of Environmental NGOS :

Conducting education and citizen awareness programmes in the field of Environment. Fact - finding and analysis.


118

Filing public interest litigations

Providing expertise and policy analysis

Providing factual and reliable information with a network of professional expert staff. Solidarity and support to environmental defenders. Working out at the grassroots level and reaching far - flung areas with or without the

government invitation. Limitations in the performance of environmental NGOs in India

Lack of research and development facilities.

Financial constraints. Lack of cooperation from the governmental agencies.

Difficulties in the mobility on account of lack of transport facilities. Examples of NGO working in India are: TERI (INDIA): Tata Energy Research Institute (TERI) was formally established in 1974 with the purpose of tackling and dealing with the immense and acute problems. that mankind is likely to be faced with in the Years ahead :

On account of the gradual depletion of the earth’s finite energy resources which are largely non-renewable.

On account of the existing methods of their use which are polluting.

13.1.10 Environmental ethics Environmental ethics refers to-the issues, principles and guidelines relating to human interactions

with their environmental. Environmental ethics is the discipline that studies the moral relationship of human beings to, and also the value and moral status of, the environment and its non human contents. Importance of Environmental ethics

Environmental ethics makes us aware of the indiscriminate and destructive human activities. We inculcate moral values towards nature and learn to respect various life forms through environmental ethics.

Environmental ethics is concerned with the issue of responsible personal conduct with respect

to natural landscapes, resources, species, and non-human organisms. Conduct with respect to person, is, of course, the direct concern of moral philosophy as such. Objectives of Environmental Ethics

Understand the concepts of basic and non-basic rights, morals, and deontological and teleological ethical perspectives.

Understand the influence of differing cultural value systems on relationships of humans,

with each other and with plants, animals and the land. Articulate responsibilities humans may have regarding global posterity.

Comprehend the connections and interrelatedness among all beings, human and non-

human, life, and the globe up on which all the well.

Develop original and sustaining attitudes and guidelines which will enhance a healthy personal future and a healthy global enterprise.


119

Read and comprehend academic and professional literature on the subjects of environmental ethics and philosophy.

Basics of Environmental studies · 2110007 – ES – Study Material 2 Contents 1 INTRODUCTION TO...

Documents

Transcript of Basics of Environmental studies · 2110007 – ES – Study Material 2 Contents 1 INTRODUCTION TO...