Chapter-1

INTRODUCTION TO ENVIRONMENTAL STUDIES

The term environment is derived from a French word environner which means ‘surrounding’. It refers to an aggregate of all conditions that affect the existence, growth, and welfare of an organism or a group of organisms.

Environment is the sum total of all social, economical, biological, physical, and chemical factors which constitute the surroundings of humans, who are both creators and moulders of the environment.

Definitions

Environment is the sum total of influences which modify and determine the development of life and its associated characteristics.

The elements of environments are interconnected to each other in a complicated way (spider web) : disturbance of one element will affect the other

one.

Components of Environment

The components of environment are broadly classified as abiotic and biotic components.

Abiotic or non-living components of environment include all the physical and chemical factors that influence living organisms. Examples of abiotic components are air, water, soil, rocks, etc.

Biotic or living components are the living components of environment and include microbes, plants, animals, and human beings.

Biotic Components

Abiotic Components

Types of Environment

Natural Environment

Man-Made Environment

•Lithosphere: Crust: < 1% (Thin)

Everest: 8.85 km Mantle, Cores

•Hydrosphere: (oceans, sea, rivers)

•Atmosphere: ~1%:

30 km (99% of air)

extends to 120 km

•Biosphere: All life

Planet Earth: Segments of Environment

Environmental Studies

Environmental Studies refers to the study of the environment. It is not restricted to the point of view of one particular discipline but involves all disciplines that may affect the environment in any possible way.

It involves the study and understanding of the fact that even a single phenomenon can affect the environment in a variety of ways with varying degrees of complexity, and each of these effects can be understood from different perspectives rooted in different disciplines.

Multidisciplinary Nature of Environmental Studies

Environmental Studies requires skills that encompass a range of disciplines including chemistry, biology, earth sciences, atmospheric

science, statistics, mathematics, and geography.

Importance of Environmental Studies

Environmental Studies is useful in checking environmental pollution and related solutions.

It helps in maintaining ecological balance.

It helps to gain skills to assess the environmental impact of human activities. Environmental study will help to protect biodiversity.

It gives us basic knowledge of environment and associated problems. It helps to achieve sustainable development .

It helps to educate people regarding their duties towards the protection of environment.

The knowledge of environmental science will be applied to the study of

agriculture.

Need for Public Awareness

Earth’s resources are dwindling and our environment is being increasingly degraded by human activities and hence something needs to be done.

Government alone cannot perform all the clean-up functions.

Individual/group efforts in their own every possible way has to be made to protect our environment.

Mass public awareness: newspapers, radio, television strongly influences public opinion on conserving our environment.

Methods for Public Awareness

Environmental education Through media Through organizing seminars & conferences Entertainment Science centers Involvement of youth Through print, broadcast and internet

ECOLOGY

How does “Environment” differ from “Ecology”

Ecology

(Greek word: Okologie; meaning: “place to live”)

“Physical, biological and socio cultural adaptations”

Branch of science that deals with the scientific study of the

interrelationships between living organisms with respect to

each other and to their surroundings.

Sustainable Development

The concept of sustainable development can be interpreted in many different ways, but at its core is an approach to development that looks to balance different, and often competing, needs against an awareness of the environmental, social and economic limitations we face as a society.

All too often, development is driven by one particular need, without fully considering the wider or future impacts. We are already seeing the damage this kind of approach can cause, from large-scale financial crises caused by irresponsible banking, to changes in global climate resulting from our dependence on fossil fuel-based energy sources.

The term sustainable development refers to the development that meets the needs of the present without compromising the ability of the future generations to meet

their own needs.

Measures for Sustainable Development

Effective planning for population control

Reducing per capita demand of natural resources

Using efficient technological devices

Following the 3Rs (reduce, reuse, and recycling) approach

Promoting environmental awareness through education

Effective planning for regeneration of natural resources

Sustainable Building Materials: Approach

Green buildings

Green building (also known as eco buildings or sustainable building) refers to a structure and using process that is environmentally responsible and resource-efficient throughout a building's life-cycle: from siting to design, construction, operation, maintenance, renovation, and demolition.

Efficiently using energy, water, and other resourcesProtecting occupant health and improving employee productivityReducing waste, pollution and environmental degradation.

Objective of green buildings

Designed to reduce the overall impact of the built environment on human health and the natural environment

Environmental benefitsEnhance and protect biodiversity and ecosystemsImprove air and water qualityReduce waste streamsConserve and restore natural resourcesEconomic benefitsReduce operating costsCreate, expand, and shape markets for green product and servicesImprove occupant productivityOptimize life-cycle economic performanceSocial benefitsEnhance occupant comfort and healthHeighten aesthetic qualitiesMinimize strain on local infrastructureImprove overall quality of life

 Potential benefits of green building

Why Build Green? merits of green building

Classification of Natural Resources

Resources whose continual harvest is possible with proper planning and management, such as plants, animals, solar energy, wind energy, etc., are known as renewable resources. (They can renew themselves, provided they are not over harvested).

Renewable Resources

Those resources which once gone have very little chance of recoveryor resynthesis are called non-renewable resources. Examples of non-renewable resources are coal, minerals, and petroleum. (Total stock islimited).

Non-renewable Resources

Our natural resources

water forest energy land food minerals

The rainforest in Fatu-Hiva, in Marquesas Islands is an example of an undisturbed natural resource. Forest provides timber for

humans; food and shelter for flora and the fauna. The nutrient cycle between organisms form food chains and biodiversity of

species.

The Carson Fall in Mount Kinabalu, Malaysia is an example of undisturbed

natural resource. Waterfalls provide spring water for

humans, animals and plants for survival and also habitat for marine organisms. The

water current can be used to turn turbines or 

hydroelectric generation.

The ocean is an example of a natural resource. Ocean waves can be used to generate wave power which is a renewable energy.

Ocean water is important for salt production and providing habitat for deep water fishes. There are biodiversity of marine

species in the sea where nutrient cycles are common.

Wind is a natural resource that can be used to generate

electricity, as with these 5MW wind turbines in 

Thorntonbank Wind Farm 28 km (17 mile) off the coast of 

Belgium

Natural ResourcesNatural Resources UsesUses

Air (Wind) Air (Wind) Required for all living things for breathing, Use to Required for all living things for breathing, Use to

produce wind energy. produce wind energy.

Animals / Plants Animals / Plants Provide food, cloth, shelter, medicine. Used as mode Provide food, cloth, shelter, medicine. Used as mode

of transport. Animal dung can be used as of transport. Animal dung can be used as

fuel/fertilizer. fuel/fertilizer.

Soil Soil Used as the primary nutrient source for plants. It is Used as the primary nutrient source for plants. It is

the habitat of many organisms. the habitat of many organisms.

Solar LightSolar Light Provide light, energy and help to plants for making Provide light, energy and help to plants for making

their foods their foods

Wood / Tree Wood / Tree Used as construction material. Used to make Used as construction material. Used to make

utensils, furniture and sporting equipments. utensils, furniture and sporting equipments.

Water Water Used in household, agriculture and transportation. Used in household, agriculture and transportation.

Examples of Renewable Resourcessolar energy

Hybrid Of Wind And Solar energy

Biomass Energy

COAL OIL NATURAL GAS OIL SHALE AND TAR SANDS NUCLEAR POWER

Over 85% of the energy used in the world is from non-renewable supplies

Most developed nations are dependent on non-renewable energy sources such as fossil fuels (coal and oil) and nuclear power.

Industrialized societies depend on non-renewable energy sources.

Examples of Non-renewable Resources

Land Resources

The Importance of Land

The human civilization has thrived on land.

Land is used for agriculture.

Land contains huge amount of mineral deposits.

It also contains water in the form of underground water.

Most of the animals find their habitat on land.

Land directly or indirectly provides all the resources required to fulfil the basic needs of humans: food, cloth, and shelter.

Soil profile

Soil profile is a vertical cross section from surface down to the

parent materials. A well- developed soil profile shows distinct

horizons.

The three major horizons are A, B, and C horizons. Horizons are

sometimes also called zones.

The soil profile is important tool for nutrient management and soil

fertility.

Decomposition of weathers and organic matter, profile of the soil

changes.

The soil profile is made of distinct layers , known as horizons.

Five most common horizons are collectively known as master

horizons.

Study of soil profile is essential for proposed the soil structure and

for technical descriptions.

Horizons in Soil profile

Functions of Soil

Role in nutrient cycles In agricultureRegulate the waterRegulate the emissions of gasesDegrade pollutants and filter ground waterProducing clayProvide the structural material as brick, cement etc. Sequester carbon as organic matter.

Land Degradation

The fertility of land supports the growth and productivity

of natural vegetation and agricultural crops. A number of

natural and man-made factors lower the quality of land.

This is commonly referred to as land degradation.

Causes of land degradation

Natural factorsHeavy rainsHigh speed wind and stormsNatural disasters like earthquakes ,floods, prolonged drought, etc.

Anthropogenic factorsMining.UrbanizationThe indiscriminate and uncontrolled removal of treesExcess use of fertilizersIndustrial dischargesOvergrazing, soil erosion, etc..

Soil Erosion

Soil erosion is removal of top soil from its resting place by various

physical agencies like wind and water. It can be defined as “the

detachment and transport of the fertile layer of soil by water or air.”

It is also known as the creeping death of land.

The detachment and transportation of the fertile layer of soil by water or

air.

Causes of Soil Erosion

Large-scale deforestation for meeting commercial as well as day-to-day needs

Heavy floods in rivers

Overgrazing by cattle

Dry violent winds

Improper agricultural techniques

Effects of Soil Erosion Desertification of land

Decrease in productivity of land

Reduction in the agricultural land at the banks of rivers

Deposition of soil in river beds and canals causing diversion of their natural flow and hence leading to disasters

Tillage is the agricultural preparation of soil by mechanical agitation of

various types, such as digging, stirring, and overturning.

Contour farming is the farming practice of planting across a slope following its elevation contour lines

Strip farming is defined as alternating crop rows between

heavy-rooted plants and loosely-rooted plants to minimize erosion.

Terrace cultivation is method of growing crops on sides of hills or

mountains by planting on graduated terraces built into the slope.

Methods of Controlling Soil Erosion Reduced tillage

Contour cultivation

Strip cropping

Terracing

A forestation on barren land

Control of overgrazing

Construction of small check dams

Promotion of equitable use of water resources

Prevention of excavation of rocks

Strip cropping Contour banding

Terracing

Methods to control Soil Erosion

Afforestation

Construction of small check dams

Desertification

Causes of Desertification

Natural Factors

Very low rainfallHigh salinity of soils Excessive evaporation

Vast difference in diurnal temperature extremes

Anthropogenic Factors

Overgrazing Over irrigation

Excessive ploughing Excessive use of fertilizers Continuous cutting of trees

Conversion of fertile land into an infertile desert land is called desertification.

Effects of Desertification

Poor soil quality

Rapid soil erosion

Unfavorable climate

Huge economic losses

Low water table, salty and hard water

Control of Desertification

Promoting large-scale plantation of trees

Changing agricultural practices and promoting dry land farming

Development of pasture lands (suitable for Grazing) and control of overgrazing

Promoting equitable use of water resources

Development of water catchment areas

The desertification is increasing significantly in Bhuj in northern Gujarat due to over usages of ground water for last 20 years.

Water tables going down by 3m/year.

Forest Resources

A forest is a biotic community with a predominance of trees; it is an important renewable resource.

Forests restore oxygen in our atmosphere through photosynthesis and also provide solvents, medicines, fuels,

and many other products that are important for our health and comfort.

India is rich in forest resources with a great diversity of flora and fauna.

The effect of desertification in Northern Gujarat

The desertification is increasing significantly in Bhuj in northern Gujarat due to over usages of ground water for last 20 years.

Water tables going down by 3 m/ year

According to the Experts, it is spreading to nearby villages

Parameters such as groundwater level, vegetation, soil and rain are showing an alarming decline and rapid degradation

Every ecological and political bodies are warned to people about this degradation.

Importance of Forests

Forests provide timber for construction of buildings and furniture.

They provide raw material for a number of large- and small-scale industries. (bee keeping, Furniture, beedi, sal seed oil, bamboo sticks)

They provide a variety of edible products for human beings and animals.

They provide natural habitat to tribal people.

Direct Benefits

They make manure (organic matter used as organic fertilizer in agriculture) and fuel wood available to humans.

They are an important source of national income.

They provide various medicinal plants.

They increase the beauty of landscape and attract tourists.

They are extremely helpful in generating employment opportunities.

Indirect Benefits

Forests help in minimizing natural hazards.

They help in reducing soil erosion and siltation of downstream water bodies.

They help in reducing desertification and land degradation.

They help in maintaining biodiversity by providing habitat to wild animals.

They help in regulating hydrological cycle.

They help in regulating the gases in atmosphere.

A conifer forest in the Swiss Alps

Mixed deciduous forest in Serbia

Temperate rainforest in Tasmania's Amazon Rainforest in Brazil

Indian top five states with largest area under forest cover

According to India's 2013 forest survey report, thus obtained and published by the Government of India suggests the top five states with largest area under forest cover:

Madhya Pradesh: 7.75 million hectares

Arunachal Pradesh: 6.73 million hectares

Chhattisgarh: 5.6 million hectares

Maharashtra: 5.06 million hectares

Odisha: 5.03 million hectares

The seven north-eastern States of India have nearly 1/4th of the country’s forest cover.

Deforestation

Causes of Deforestation

Encroachment of forest land for agricultural use to meet the growing demands of foods.

Expansion of cities to accommodate the growing population Construction of dams, canals, and highways

Establishment of industrial areas

Demand for firewood

Mining

The term deforestation refers to the removal or reduction of forest cover.

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 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, paper, match box etc results into tremendous pressure on forests.

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

Forest fires: Forest fires may be natural or man made 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

Human activities have a very adverse impact on forests

Even deserts are affected by

human activities

Mountain ecosystems

provide vital ecosystem

services, but they are facing

severe degradation due

to climate changing.

Effects of Deforestation

Loss of natural habitat of wild animals and plants

Increased intensity and frequency of floods

Land degradation

Loss of forest products

Change in climatic conditions

Siltation of rivers and lakes

Loss of revenue

Change in hydrological cycle and reduced rainfall

Increased socio-economic problem in the long run

Cherrapunji was famous because it received the largest volume of

rainfall in the world It still does but ironically, experiences acute water

shortages. This is mainly the result of extensive deforestation (no trees to

hold the water and the water run off to rivers. Because proper methods of

conserving rainwater are not used. There has been extensive soil erosion.

Only rain water harvesting can sort out the problems of the world's

wettest town. Scientists point out the example of Jaisalmer, one of the

driest towns in India in Rajasthan, with rainfall levels as little as 100 mm

of water per year, where it was found that if you harvest water on just

one hectare of land, you have captured as much as one million litres of

water --enough to meet drinking and cooking water needs of 182 people

at 15 litres per day for one year.

Control of Deforestation

Mining activities should be prohibited in areas declared as protected forests.

Cutting of trees should be followed by massive plantation.

The environmental laws and legal provisions should be strictly enforced.

Public awareness should be created regarding medicinal and other economic and environmental significance of forests.

.The story of Wangari

Maathai

Nobel Prize for noble work

First woman in Africa to get a Ph.D.

Green Belt Movement (GBM) in 1977.

Empower the people

Participation of locals in forest conservation

The story of Chipko: The local women who saved the trees

Afforestation

Functions of Forests

The functions of forest may broadly classified into following categories

•Protective Function•Productive Function•Regulative Function•Accessory Function

Protective Functions

Forest Provide protection against • Soil erosion • Droughts• Floods• Noise• Radiations

Soil erosion FloodsSoil erosion

Droughts

Productive Functions

Forest Provide various products like, gum resins, medicines, honey, pulp, bamboo, timber, Vegetables and fruits.

Regulative Functions

The Forest regulates the level of Oxygen and carbon dioxide in atmosphere.

The forests also help in regulating temperature conditions

Accessory Function

Forest provides aesthetics, habitat to various flora and fauna besides that it also has an recreational value.

Ecological Importance 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 regulate the hydrological cycle

Reduction of Global Warming

The main green house gas co2 is used by forests for

photosynthesis process the forest act as a sink for co2 there by reducing the green house effect due to co2.

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

Conservation of Soil

They prevent soil erosion by binding the soil particles tightly in their roots. reducing the velocity of wind and rain which are chief agents causing erosion

Improvement in fertility of Soil

The fertility of soil increases due to humus formed by the decay of forest litter (leaves, branches, stems roots etc.)

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

Absorption of Noise

Forest cover absorbs the noise and helps in preventing noise pollution

Absorption of air pollutants

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

Economical Importance of Forest

Timber: Wood used for commercial purposes like for making furniture and other items like boats, bridges 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, 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.

Miscellaneous Products: Miscellaneous products like, resin, gums, oils, medicines, honey are provided by forests

Water Resources

Importance of Water

Water is the basic component of every living cell.

It is the basic input required for agriculture.

Hydel power can be used for generating hydroelectricity.

It provides habitat to aquatic flora and fauna.

Common salt can be obtained from water.

Earth: “Blue Planet”

Sources of Water

Ground Water

Surface Water

Water that is hidden underground in spaces between soil and rock particles is known as ground water. This ground water is the source of water for wells, springs, and even to rivers. Rainwater seeps into the ground, some are clings to particle or to the root of the plants. This moisture is provided to the plants for their growth. Most water moves deeper into ground. Most usable water is at depth of 750 m.

After precipitation, the amount of water that does not percolate down into the ground or does not return to the atmosphere by evaporation or transpiration and enters the rivers, streams, lakes, ponds, wetland, or artificial reservoirs constitutes surface water.

Ground water is purer than surface water, the chance of pollution is less in ground water.

Water Cycle

Water never leaves the Earth. It is constantly being cycled through the atmosphere, ocean, and land.

Effects of Over-utilization of Ground Water

Reduced flow of surface water

Lowering of water table

Water logging (saturation of the soil by groundwater)

Subsidence

Degradation of water quality

Increased salt content

Increased power costs

Water Calamities: Floods and Droughts

Floods

Floods refers to the presence of unusually large amount of water

at any place or more water that can be handled by the drainage

of the area. The various types of floods are

Flash Floods (due to sudden heavy rain fall, dam failure)

River floods (when rain over large the catchment area slowly, melting of snow)

Coastal Floods (due to cyclonic activity like hurricanes, tropical cyclones)

Drought

A drought is a condition in which a region suffers from a severe scarcity in its water availability.

Various kinds of drought

Meteorological Drought (Actual rainfall is less than climatological mean of that area)

Hydrological Drought (Running down of surface water leading to a very low stream flow and drying of lakes, rivers.

Agricultural Drought (In adequate soil moisture result in fall in agricultural productivity)

Water Woes: Junagarh

Junagarh in Gujarat, indiscriminate consumption of ground water has caused an alarming decrease in the water table.

Reasons:

Person that can afford to dig a bore-well, did so without adhering to any limit regarding its depth.Motors are used to withdrawn large amount of water.Reduction of water tables by 20% in every summer.Women have to move up to 4 km in search of water.Ingress of sea water is the another problems faced by villagers, increases the salinity in ground water and soil, health issues are increased.Hardness is increased in water.

Energy Resources

Renewable Energy Sources

Renewable sources of energy or flow sources, rely on natural energy flows and sources in the environment and thus have the potential of being continually replenished. These include firewood, animal dung, solar energy, wind energy, geothermal energy, tidal energy, etc.

Non-renewable Energy Sources

Non-renewable energy sources are available in limited amount and develop over a longer period. Because of indiscriminate use they are likely to be exhausted in the near future. These include coal, mineral oil, natural gas, nuclear power, etc.

Renewable Sources of Energy

Solar Energy

Wind Energy

Tidal Energy

Geothermal Energy

Biomass Based Energy (natural vegetation, animal waster)

Non-Renewable Sources of Energy

Coal

Natural gas and oil

Nuclear energy (Controversial, because use of the radioactive substance but it does not emit any green house gas or toxic

gases.

Use of alternative source of energy

15 European union nations including Spain and Germany have committed that by 2020, they will generate 20% of the energy using alterative energy resources.

Alternative energy resources not only save the non renewable energy resources from being used up but also it’s a green and clean technology.

India has also taken several initiatives to promote the non renewable energy resources. Currently, India is in 4th position in the world in generating wind energy.

With the increasing price of petroleum, alternative energy resources are not optional but mandatory.

India plans to manufacture biodiesel from vegetable oil.

The cost of setting up a biomass plant is same as that of coal based power plant.

Limitation of alternative energy sources

Alternative sources provide a ray of hope.

High installation costs and require maintenance.

Short in availability of material which may be used in designing and manufacturing, like as supply of silicon is short which is essential for photovoltaic cell.

Lack of human capital, affect the whole energy industry worldwide.

Still, the benefits are driving governments, businesses and individuals all-over the world to adopt this technology.

Energy Recovery

The concept is to get energy by burning the waste

By this principle the main benefits what we can get…1. Longer availability of crude oil. 2. Reduction of waste volume by upto 90%. 3. Reduced number of coal fired power plants. 4. Slow climate change.

Waste to energy plants (which is much advanced today) extract energy from

trash

This plant reduces the emission of green house gases

Disadvantages…1.Proper care must be taken on choosing the trash which is to be burn.2.Indiscriminate burning may promote air pollution and may release toxic gases. 3.Combustion of heavy metals are very harmful.

Urban Problems Related to Energy

The energy requirement in urban areas is many times greater than that in rural areas because of the following reasons:

Activities that require large amounts of energy (industries, institutions, transportation, etc.) are concentrated in urban areas.

Urban people have a higher standard of living compared to rural people and hence demand more energy for comfortable living.

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