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School of Engineering

Department of Civil Engineering

E NOTES

Environmental Science & Engineering

For

B.E. V Semester ECE & Mechanical Engineering

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ENVIRONMENTAL SCIENCE AND ENGINEERING

SYLLABUS

UNIT I INTRODUCTION TO ENVIRONMENTAL STUDIES ANDNATURAL RESOURCES

Definition - Scope and importance - Need for public awareness - Forest resources:-

Use and over - Exploitation - Deforestation - Case studies - Timber extraction -

Mining - Dams and their ground water - Floods - Drought - Conflicts over water -

Dams - Benefits and Problems - Mineral Resources: - Use Effects on Forests and

Tribal People - Water Resources: - Use and Over-Utilization of Surface and

Exploitation, Environmental Effects of Extracting and Using Mineral Resources, Case

Studies - Food Resources: World Food Problems, Changes caused by Agriculture and

Overgrazing, Effects of Modern Agriculture, Fertilizer- Pesticide Problems, Water

Logging, salinity, Case Studies - Energy Resources: - Growing Energy Needs,Renewable and Non Renewable Energy Sources, Use of Alternate Energy Sources,

Case Studies - Land Resources:- Land as a Resource, Land Degradation, Man

Induced Landslides, Soil Erosion and Desertification - Role of an Individual in

Conservation of Natural Resources - Equitable use of Resources for Sustainable

Lifestyles..

UNIT II ECOSYSTEMS AND BIODIVERSITY

Concepts of an Ecosystem - Structure and Function of an Ecosystem - Producers,

Consumers and Decomposers - Energy Flow in the Ecosystem - Ecological

Succession - Food Chains, Food Webs and Ecological Pyramids - Introduction,

Types, Characteristic Features, Structure and Function of the (A) Forest Ecosystem(B) Grassland Ecosystem (C) Desert Ecosystem (D) Aquatic Ecosystems (Ponds,

Streams, Lakes, Rivers, Oceans, Estuaries) - Introduction to Biodiversity -

Definition: Genetic, Species and Ecosystem Diversity - Biogeographical

Classification of India - Value of Biodiversity: Consumptive Use, Productive Use,

Social, Ethical, Aesthetic and Option Values - Biodiversity at Global, National and

Local Levels - India as a Mega-Diversity Nation - Hot-Spots of Biodiversity -

Threats to Biodiversity: Habitat Loss, Poaching of Wildlife, Man-Wildlife Conflicts -

endangered and Endemic Species of India - Conservation of Biodiversity: In-Situ and

Ex-Situ conservation of Biodiversity.Field Study of Common Plants, Insects and

Birds.

UNIT III ENVIRONMENTAL POLLUTION

Definition - Causes, Effects and Control Measures of:- (A) Air Pollution (B) Water

Pollution (C) Soil Pollution (D) Marine Pollution (E) Noise Pollution (F) Thermal

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Pollution (G) Nuclear Hazards - Solid Waste Management:- Causes, Effects andControl Measures of Urban and Industrial Wastes - Role of an Individual in

Prevention of Pollution - Pollution Case Studies - disaster Management:- Floods,

Earthquake, Cyclone and Landslides.

UNIT IV SOCIAL ISSUES AND THE ENVIRONMENT

From Unsustainable To Sustainable Development - Urban Problems Related To

energy - Water conservation, Rain Water Harvesting, Watershed Management -

Resettlement and Rehabilitation of People, Its Problems and Concerns, Case Studies -

Environmental Ethics:- Issues and Possible Solutions - Climate Change, Global

Warming, Acid Rain, Ozone Layer Depletion, Nuclear Accidents and Holocaust, Case

Studies - Wasteland Reclamation - Consumerism and Waste Products - Environment

Production Act - Air (Prevention and Control of Pollution) Act - Water (Prevention

and Control of Pollution) Act - Wildlife Protection Act - Forest Conservation Act -

Issues Involved in enforcement of Environmental Legislation - Public Awareness.

UNIT V HUMAN POPULATION AND THE ENVIRONMENT

Population Growth, Variation Among Nations - Population Explosion - FamilyWelfare Programme - environment and Human Health - Human Rights - Value

Education - HIV /AIDS - Women and Child Welfare - Role of Information

Technology in Environment and Human Health - Case Studies.

Field Study of Local Area to Document Environmental assets -

River/Forest/Grassland/Hill/ Mountain.

Field Study of Simple Ecosystems - Pond, River, Hill Slopes, etc

Field Study of Local Polluted Site - Urban/Rural/Industrial/Agricultural

UNIT I INTRODUCTION TO ENVIRONMENTAL STUDIES AND

NATURAL RESOURCES

Definition - Scope and importance - Need for public awareness - Forest resources:-

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Use and over - Exploitation - Deforestation - Case studiess - Timber extraction -Mining - Dams and their ground water - Floods - Drought - Conflicts over water -

Dams - Benefits and Problems - Mineral Resources:- Use Effects on Forests and

Tribal People - Water Resources:- Use and Over-Utilization of Surface and

Exploitation, Environmental Effects of Extracting and Using Mineral Resources, CaseStudies - Food Resources: World Food Problems, Changes caused by Agriculture and

Overgrazing, Effects of Modern Agriculture, Fertilizer- Pesticide Problems, Water

Logging, salinity, Case Studies - Energy Resources:- Growing Energy Needs,

Renewable and Non Renewable Energy Sources, Use of Alternate Energy Sources,

Case Studies - Land Resources:- Land as a Resource, Land Degradation, Man

Induced Landslides, Soil Erosion and Desertification - Role of an Individual in

Conservation of Natural Resources - Equitable use of Resources for Sustainable

Lifestyles..

UNIT - I

Introduction to Environmental Studies

Introduction:

Environment is a French word meaning surrounding.

All biological and non biological things surrounding an organism is called an environment.

Environment:

It is also defined as the sum of total of water, air and land, interrelationship among themselves and

also with the human beings, other living organisms and property.

Environmental Science:

It is the study of environment, it's biotic and abiotic and their inter relationship.

Environmental Engineering:

It is the application of engineering principles to the protection and enhancement of the quality

of the environment and to the enhancement and protection of public health and welfare.

Environmental education:

It is the process of educating the people for preserving quality environment.

Types of environment:

1. Natural environment

2. Man made environment

Natural environment:

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All natural things, biotic and abiotic are collectively called natural environment.

(e.g.) soil, water, tree and air.

Manmade environment:

Created by man

Powerful engineering agent

Man modifies the environment using modern technologies according to his necessity.

Component of environment:

Consist of 3 components

1. Abiotic (or) non living

2. Biotic (or) living

3. Energy component

Abiotic component:

3 categories atmosphere, lithosphere, hydrosphere.

Atmosphere:

The air that covers the earth is known as atmosphere. It is 500 km from earth. It is essential for

All living organisms. 78% N2, 21% O 2 and 1% other gases.

Structure of atmosphere:

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Region

Troposphere

Stratosphere

Mesosphere

Thermosphere

Altitude in Km

0 -15

18 - 50

50 - 85

85 - 500

Temperature in

15 to -56

-56 to -2

-2 to -92

-92 to 1200

O

CChemical species

N2, H2o, Co2, O2

Ozone

No+, O2+

No+, O+, O2+

Troposphere (1 to 15 km)

75% atmospheric air

Contain moisture

Stratosphere (18 to 50 km)

Consists of large amount of O3

Free from moisture and clouds

Prevents UV radiation from sun

Mesosphere (50 to 85 km)

Less ozone

More nitrogen oxide

Function of atmosphere:

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1. It maintains heat balance on the earth by absorbing the IR radiations.

2. Gases present in atmosphere are essential for sustaining life.

Oxygen - supports life

Carbon dioxide - essential for photosynthesis of plants

Nitrogen - essential nutrient for plant growth.

Lithosphere:

It consists of soil and rock components of earth.

Function:

Home for human beings and wild life.

Store house of minerals and organic matter.

Hydrosphere:

The aquatic envelope of the earth. It includes oceans, lakes, streams, river and water vapour. In

the hydrosphere 97% of water is not suitable for drinking and only3% is fresh water.

Functions of hydrosphere:

Drinking purpose

Irrigation

Power production

Industries and transport

Biotic or living component:

(e.g.) Animals, plants and micro organisms.

Biosphere:

Interaction of biological environment with physical environment is called biosphere.

Energy component:

Flow energy across biotic and abiotic components. It plays an important role in living

organisms. (e.g) solar energy, nuclear energy, geo thermal energy etc.

SCOPE OF ENVIRONMENTAL STUDIES

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1. This study crates awareness among the people to know about various renewable and

renewable resources of a region. The endowment or potential, pattern of utilization a

the

balance of various resources available for future use in the state or a country are analyzed in

the study.2. It provides the knowledge about ecological system causes, effects and relationships betw

the components.

3. It provides necessary information about biodiversity richness and the potential dangers to the

species of plants, animals and microorganism in the environment

4. This study enables one to understand the causes and consequences of natural and man induced

disasters, pollutions and measures to minimize theses effects.

5. It enables one to evaluate alternative responses to environmental issues before deciding

alternative course of action.

6. This study enables environmentally literate citizens to make appropriate judgmen

and

decisions for the protection and improvement of the earth.7. This study exposes the problems of over pollution, health, hygiene etc and the role

arts,

science and technology in eliminating the evils from the society.

8. This study tries to identify and develop appropriate and indigenous eco friendly skills

technologies to various environmental issues.

IMPORTANCE OF ENVIRONMENTAL STUDY

1. World population is increasing at an alarming rate especially in developing countries.

2. The natural resources endowment in the earth are limited.

3. The methods and techniques of exploiting natural resources and advanced.

4. The resources are over-exploited and there is no foresight of leaving the resources of the future

generations.

5. The unplanned exploitation of natural resources lead to pollution of all types and at all levels.

6. The pollution and degraded environment seriously affect the health of all living things on earth,

including man.

7. The people should take a combined responsibility for the deteriorating environment and begin

to take appropriate actions to save the earth.

8. Education and training are needed to save the biodiversity and species extinction.

9. The urban areas, coupled with industries, are the major sources of pollution.

10. The number and area of the protected are should be increased so as to protect the wild life.NEED FOR PUBLIC AWARENESS

1. Individuals of school, colleges, industries, service centers, village, urban centers etc.should

realize the importance of day to day environmental issues.

2. The individuals should practice environmental conservation principles and create awaren

among family members.

3. The individuals could expose the problems by writing in the newspapers/discuss about

environmental evils in forums and make the people to become aware of the same.

4. There is a need to meet the people and discuss again and again, so that the problem is alive till

it is eliminated.

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5. The Nongovernmental organizations, in India and abroad, are doing tremendous efforts

in

conserving the environment.

Types of public participation;

1. Pressure group

2. Watch dog

3. Advisory council

4. Enforcing the environmental laws.

Chinese proverb

" If you plan for one year, plant rice, If you plan for 10 years plant trees and if you plan for 100

ears educate people"

Natural resources:

Natural resources are the source which are useful to man or it can be transformed into a useful

roduct.

Two types

Renewable resources

These resources are capable of being regenerated by ecological processes within a reasonable

time period. Example Soil, water, air

Non Renewable resources

These resources are not capable of being regenerated by ecological processes.

RESOURCES

FOREST RESOURCES,

WATER RESOURCES,

MINERAL RESOURCES,

Forest resources:

ENERGY RESOURCES

LAND RESOURCES

FOOD RESOURCES

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rd

One of the important renewable natural resource on earth. 1/3 of the world's land surface is

covered with forest. Forest covering the earth like a green blanket. Forest not only produce

innumerable material goods, but also provide several environmental services.

Types of forest:

Ever green forest:

Found in equatorial region. Where temperature and rain fall is high, due to heavy rain the

orest are ever green. (e.g) silent valley in kerela

Important trees teak and rosewood.

Deciduous forest:

These forest receive only seasonal rainfall. Therefore they loose their leaves during summer

season. Trees sandal wood.

Coniferous trees:

Trees contain needle shaped leaves (e.g) pine tree, spruce tree

Functions of forest:

1. It performs very important function both to human and to nature.

2. They are habitats to millions of plants, animals and wild life.3. They recycle rain water.

4. They remove pollutant from air.

5. They control water quality.

6. They moderate temperature and weather.

7. They influence soil condition and prevent soil erosion.

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8. They promote tourism.

Uses of forest:

1. Commercial uses

2. Ecological uses

Commercial uses:

1. Wood - used as a fuel

2. Supply wood for various industries - Raw materials as pulp, paper, furniture timber etc.

3. Minor forest products - gum, dyes, resins

4. Many plants - Medicines

5. Supply variety of animal products - honey. Ivory, horns etc.6. Many forest lands are used for - Mining, grazing, for dams and recreation.

Ecological uses:

Forest provides number of environmental services.

1. Production of oxygen:

Photosynthesis produces large amount of oxygen which is essential for life.

2. Reducing global warming:

Carbon dioxide is one of the main green house gas. It is absorbed by plants for photosynthesis.

Therefore the problem of global warming caused by CO 2 is reduced.

3. Soil conservation:

Roots of trees bind the soil tightly and prevent soil erosion. They also act as wind breaks.

4. Regulation of hydrological cycle:

Watershed in forest act like giant sponges and slowly release the water fore recharge of spring.

5. Pollution moderators:

Forest can absorb many toxic gases and noises and help in preventing air and noise pollution.

6. Wild life habitat:

Forest is the homes of millions of wild animals and plants.

Over exploitation of forest:

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Due to over population, there is a demand fort medicine, shelter, wood and fuel increases.

Hence exploitation of forest material going on increases.

Reason for deficiency of forest:

In India the minimum area of forest required to maintain good ecological balance is about 33%

of total area. But at present it is only about 22%. So over exploitation of forest material occur.

Cause of over exploitation:

1. Increasing agricultural production.

2. Increasing agricultural activities.

3. Increase in demand of wood resources.

Deforestation:

It is process of removal of forest resources due to natural or man made activities (i.e.)

destruction of forests.

Deforestation in India:

In India 1.3 hectare of forest land has been lost.

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Causes of deforestation:

1. Developmental projects:

Developmental projects causes deforestation through two ways.

Through submergence of forest area.

Destruction of forest area.

(e.g) big dams, hydro electric projects, road construction etc.

2. Mining operations:

It reduces forest areas. (e.g.)Mica, coal, Manganese and lime stone.

3. Raw materials for industries:

Wood is an important raw material for various purposes. (e.g.) making boxes, furniture and

paper etc.

4. Fuel requirement:

Wood is the important fuel for rural and tribal population.

5. Shifting cultivation:

Replacement of natural forest ecosystem for mono specific tree plantation. (eg) teak

6. Forest fires:

Forest fire destructs thousands of forest.

7. Over grazing:

Over grazing by cattle reduces the cultivation land.

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CONSEQUENCES OF DEFORESTATION (or) ILL EFFECTS (or) IMPACT OF

DEFORESTATION

1. Economic loss

2. Loss of biodiversity3. Destructs the habitats of various species

4. Reduction in stream flow

5. Increases the rate of global warming

6. Disruption of weather patterns and global climate

7. Degradation of soil and acceleration of the rate of soil erosion.

8. Induces and accelerates mass movement / land slides.

9. Increases flood frequency, magnitude / severity.

10. Breaks the water cycle

11. Breaks the nutrient cycle

12. Loss of forests put additional pressure on the pristine forests.

PREVENTIVE MEASURES (OR) AVOID OF DEFORESTATION (OR) METHODS OF

CONSEVATION OF FORESTS

1. New plants of more or less of the same variety should be planted to replace the trees cut down for

timber

2. Use of wood for fuel should be discouraged.

3. Forest pests can be controlled by spraying pesticides by using aero planes

4. Forest fire must be controlled by modern techniques.

5. Over grazing by cattle must be controlled.

6. Steps should be taken by the government to discourage the migration of people into the islands from

mainland.

7. Education and awareness programmers must be conducted.

8. Strict implementation of law of Forest conservation Act.

Case study:

Deforestation in the Himalayan region, involves clearing of natural forests and plantation of

monoculture like eucalyptus. Nutrient in the soil is poor, therefore soil losing their fertility. Hence

Himalayan area facing the serious problem of deforestation.

Mining:

The process of extracting mineral resources and fossil fuels like coal from the earth.

Types of mining

1. Surface mining: mining of minerals from shallow deposits

2. Underground mining: mining of minerals from deep deposits

Steps involved in mining:

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1. Exploration

2. Development

3. Exploitation

4. Ore processing

5. Extraction and purification of minerals

The extent of damage by under ground mining is less than that of surface mining, which needs

enormous amount of land area for it's operation and management.

Effects of mining:

1. Pollute soil, water and air.

2. Destruction of natural habitat.

3. Continuous removal of minerals leads to the formation of trench where water is loggedwhich contaminates the ground water.

4. Vibrations cause earth quakes.

5. Produces noise pollution

6. Reduces shape and size of the forest.

7. Some times land slides may also occur.

Dams and their effects on forests and tribal people:

Dams are the massive artificial structure built across the river to store water for much

beneficial purpose.

Dam - "Temple of modern India" - Nehru

Dams destruct vast area of forest area. India has more than 1600 large dams.

Effects of dams on forest:

1. Thousands of hectares of forest have been cleared.

2. Killing of wild animals and destruction of aquatic life.

3. Spreading of water borne diseases.

4. Water logging reduces the salinity of the soil.

(e.g) Narmadha sagar project it has submerged 3.5 lakhs hectares of forest.

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Effects of dam on tribal people:

1. Construction of big dam leads to the displacement of tribal people.

2. Displacement and cultural change affects the tribal people both mentally and physically.

3. They do not accommodate the modern food habits and life style.

4. Tribal people are ill treated by the modern society.

5. Many of the displaced people were not recognised and resettled or compensated.

6. Body condition of tribal people will not suit with new areas and hence they will be affected by

many diseases.

Water resources:

Water is essential component of all living things. 80% of earth surface is covered with water.

All organisms are made up of mostly by water.

(e.g) Tree 60% by weight of water

Animals50 - 65% by weight of water

Water exist in three phases solid, liquid and gases. It is circulated in the hydrological cycle.

Hydrological cycle:

Water from various water bodies

Evaporated by solar energy

Enters in to the atmosphere as clouds

Falls again on earth as rain or snow

Ultimately returns to the ocean.

This process is called hydrological cycle.

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Distribution of water resources:

Fresh water resources

Surface water under ground water

Standing water bodies Flowing water bodies

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1. Lakes

2. Reservoirs

3. Estuaries

1. Streams

2. Rivers

Surface water:

Water stored on the surface of earth.

Standing water bodies

Lakes:

Oligotrophic lakes:

These lakes are deep and clear. The nutrients amount is deficient. Biological reactions are less.

Eutrophic lakes:

More nutrients and more turbid. It supports more life.

Dystrophic lakes:

Shallow coloured lakes and low PH.

Reservoirs:

Generally larger than lakes.

Estuaries:

These are deltas formed at the mouth of rivers, where they join the ocean. The mixing of fresh

and salt water gives estuaries.

Flowing water bodies:

Water flows in streams and rivers. It carries sedimentary materials and dissolved minerals.

Under ground water:

Water available deep in the ground due to percolation of surface water. It is the major source. It

is very pure and used for almost all purposes in the world.

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Under ground water

Aquifer:

Layers of highly permeable rock containing water is called an aquifer. Layer of sand and

ravels are good aquifers. Clay and crystalline rocks are not good aquifers.

Effects of over utilisation of water:

1. Decrease of ground water:

Increased usage decreases the ground water.

Insufficient rain fall

Building construction activities sealing the permeability of the soil.

2. Ground subsidence:

Ground water withdrawal is greater than it's recharge rate, the sediments in the aquifers

get compacted. As a result shrinkage of land surface takes place.

Problems:

a. Structural damages in the buildings

b. Fracture in pipes.

c. Reversing the flow of canals.

3. Lowering of water table:

Over utilisation of ground water in arid and semi arid regions for agriculture disturbs

the state of equilibrium of the hydrological cycle.

Problem:

a. lowering of water table

b. decrease the number of aquifers

c. Change the speed and direction of water.

4. Intrusion of salt water:

In coastal area over exploitation of ground water leads to the intrusion of salt water from sea.

Therefore that water cannot be used for drinking and agriculture.

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5. Over utilisation of water causes earth quakes, land slides and famine

6. Drying up of wells:

Due to over utilisation, ground water level decreases much faster than can be regenerated. It

leads to drying up of dug well and bore wells.

7. pollution of water:

Near the agricultural land ground water decreases therefore water containing

nitrogen enters into the ground and pollute the ground water.

Problem:

Water which contains excess nitrate content is not suitable for drinking.

Flood:

It is an over flow of water. It happens when the magnitude of flow of water exceeds the

carrying capacity of the channel within its bank.

Causes of flood:

1. Heavy rainfall, melting of snow (i.e) sudden release of water from dams.

2. Reduction in the carrying capacity of the channel.

3. Deforestation, mining and over grazing increase the run off from rains and the level of flood

raises.

Effect of flood:

1. Water spreads in the surrounding area and submerges them.

2. Cultivated land affected.

3. Extinction of civilisation.

Flood Management:

1. Floods can be controlled by dams.

2. Channel management and embankment also control flood.

3. Flood hazards reduced by forecasting or flood warning.

4. Flood may also be reduced by reduction of run off by increasing infiltration through

appropriate afforestation in the catchment area.

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Drought:

Drought is nothing but scarcity of water, which occurs due to

1. Inadequate rain fall

2. Late arrival of rain fall

3. Excessive withdrawal of ground water.

Lack of water for the narrow needs of agriculture, livestock, industry or human population may be

termed as a drought. Drought causes serious damages to plants, animals and human life.

Types of drought:

1. Meteorological drought:

It occurs when the total amount of rain fall is less than 75% of the normal rain fall. It will be

severe if the rain fall is less than 50%.

2. Hydrological drought:

It occurs when the total amount of rainfall is less than the average rain fall. It is generally

associated with reduction of water in aquifers, lakes and reservoirs.

3. Agricultural drought:

It occurs due to the shortage as well as timing of over all rain fall, which intern reduce the

ground water level and reservoir level. Agricultural drought affects cropped plants.

4. Socio economic drought:

It occurs due to reduction in the availability of food and social security of the people in the

affected areas. Socio economic drought leads to famine.

Causes of drought:

1. When annual rain falls below normal and less than evaporation, drought is created.

2. High population.

3. Intensive cropping pattern

(e.g.) Maharashtra

There has been no recovery from drought for the last 30 years due to over exploitation of water by

sugarcane crop.

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Effects of drought:

1. Drought causes hunger, malnutrition and scarcity of drinking water an also changes the

quality of water.

2. Drought causes widespread crop failure leading to acute shortage of food and adversely

affects human and live stock population.

3. Worst situation of drought causes desertification.

4. Raw materials of agro based industries are critically affected during drought time,

hence industrial and commercial growth decreases.

5. Drought increases the degradation of natural resources.

6. Drought causes large migration of people and urbanisation.

Drought management:

1. Indigeneous knowledge is essential.

2. Rain water harvesting system.

3. Construction of reservoir to improve ground water level.

4. Modern irrigation technology (drip irrigation) very useful to conserve water.

5. Afforestation activities also improve the potential of water in the drought area.

6. Crop mixing and dry forming are the suitable methods which minimise the risk of crop

failures in dry area.

Conflicts over water:

Causes of water conflict:

1. Conflict through use:

Unequal distribution of water led to inter state and international disputes.

National conflicts:

a. Sharing of cauvery water between Karnataka and TamilNadu.

b. Sharing of Krishna water between Karnataka and Andrapradesh

c. Siruvani - TamilNadu and Kerala

International conflicts:

a. Indus - India and Pakistan

b. Colorado river - Mexico and USA

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c. Bhramaputra - India and Bangladesh

2. Construction of dams or power stations:

For hydro electric power generation, dams are built across the river. It creates

the conflicts between the states.

3. Conflicts through pollution:

Water reservoirs like lakes and rivers are also used for industrial purposes, therefore

removal industrial wastes creates conflicts.

Management of conflicts over water:

1. Efforts to implement laws to check these practices to control water pollution.

2. Conflicts over sharing of river water in the country are studied by many organisation and

several solutions are suggested.( The inter linking of rivers has been one such solution)Case study:

Conflicts on Indian River:

According to UN report, fresh water is a serious problem

1 billion people - no fresh drinking water

2 billion people - no water for proper sanitation.

(e.g) Damodhar River

Most polluted river from 45 major industries

Water resource management

S.No Organisation

1

2

3

4

5

6

7

Central water commission

Central ground water board

Indian meteorological department

Central pollution control board

Ministry of agriculture

Ministry of environment and forest

Central public health and env.engg

8

9

Department of power

Department of forest

Source

Surface water

Ground water

Precipitation

Water quality

Water for irrigation

Environmental impact assessment

Water supply, sanitation and sewage

disposal

Hydro electric power

Watershed management

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Mineral resources:

Naturally occurring substances with different physical and chemical properties.

Ores:

These are mineral or combination of minerals from which metal can be extracted.

Concentration of minerals at one particular spot is called mineral deposit.

Classification of mineral resources:

U.S geological survey divides non renewable mineral resources into 3 categories.

1. Identified resources:

Location, existence, quality and quantity known by direct geological evidence and

measurement.

2. Undiscovered resources:

Assumed to exist on the basic of geological knowledge, but their specific location,

quality and quantity are unknown.

3. Reserves:

Minerals are identified. Usable materials can be extracted profitably.

Uses and exploitation of minerals:

1. Development of industrial plants and machinery. - Fe, Al & Cu

2. Construction work - Fe, Al &Ni

3. Generation of energy - coal, lignite, uranium

4. Designing defence equipments like weapons and ornaments

5. Agricultural purposes - fertilisers and fungicides - Zn & Mn

6. Jewellery -Au, Ag & Pt

7. Making alloys for various purposes - phosphoresces

8. Communication purposes - telephone, wires, cables and electronic devices

9. Medicinal purposes, particularly in ayurvedic system - sulphur pyrites

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Classification of minerals:

Metallic minerals:

From which metals can be extracted. e.g Fe, Al & Cu

Non metallic minerals

Non metallic compounds can be extracted.e.g Quartz and feldspar

Mineral wealth of India

S.NoMineral

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

Iron

Coal

Manganese

Copper

Gold

Aluminium

Lime stone

Mica

Monozite

Lead and zinc

Precious stones

Magnesite

Petroleum

Magnesite

Gypsum

Available state

Tamil nadu

Orissa, west bangal

M.P

Bihar

Karnataka

Tamilnadu

M.P

Bhar

Kerela

Gujarat & rajasthan

Rajasthan

Tamil nadu

Assam

Tamilnadu, sikkim

Rajasthan

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Mining:

The process of extraction of minerals from the earth.

Types of mining:

1. Surface mining

2. Under ground mining

Types of under ground mining

a. Open pit mining:

Machines dig holes and remove the ores.

b. Dredging:

Chained buckets are used to extract minerals.

c. Strip mining:Bulldozers are used to extract minerals.

Environmental damages caused by mining activities:

1. Devegetation :

topsoil and vegetation are removed

deforestation leads to several ecological losses

land scape badly affected

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2. Ground water contamination:

Mining pollutes ground water , sulphur is converted into sulphuric acid which enters

into the soil.

3. Surface water pollution:

Radioactive wastes and other acidic impurities affect the surface water, which kills

many aquatic animals.

4. Air pollution:

Smelting and roasting are done to purify the metal whih emits air pollutants and

damage the nearby vegetation. It causes many health problems.

5. Subsidence of land:

Mainly underground mining results in cracks in houses, tilting of buildings and bendingof rail tracks.

Effects of over exploitation of minerals:

1. Rapid depletion of mineral deposits

2. Wastage

3. Environmental pollution

4. Needs heavy energy requirements.

Management of mineral resources:

1. The efficient use and protection of mineral resources.

2. Modernisation of mining industries

3. Search for new deposit

4. Reuse and recycling of the metals.

5. Environmental impacts can be minimised by adopting eco friendly mining technology.

Case studies;

Mining and quarrying in udaipur:

200 open cast mining and quarrying in udaipur. But 100 minings are illegal. 150 tonnes of

explosives are used per month. It pollutes air, soil and water. It affects irrigation and wild life.

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Food resources:

Food is an essential requirement for survival of life. Main components are carbohydrates, fats,

roteins, minerals and vitamins.

Types of food supply:

1. Crop plants:

Mostly produce grains about 76% of the world's food.

e.g rice, wheat and maize

2. Range lands:

It produces 17% of world's food from trees and grazing animals.

e.g fruits, milk and meat

3. Ocean:

Fisheries - 7% of world's food

World food problem:

1. In the earth's surface 79% water out of total area. 21% land(forest, desert, mountain and

barren land) . Less % cultivated land, at the same time population explosion is high

therefore world food problem arises.

2. Environmental degradation like soil erosion, water logging, water pollution, salinity affect

agricultural land.

3. Urbanisation affects agricultural land. Hence production of rice, wheat, corn and other

vegetable is difficult.

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Types of nutrition:

1. Nutritious nutrition:

To maintain good health and disease resistant, we need large amount of carbohydrate,

proteins, fats and smaller amount of micronutrients such as vitamins and minerals such

as Fe, Ca and iodine. Food and agricultural organisation (FAO) of United Nations

estimated that on an average, the minimum calorie intake on a global state is 2500

calories/day.

2. Under nutrition;

People who can not buy enough food to meet their basic energy needs suffer from

under nutrition. They receive less than 90% of this minimum dietry calorie.

Effect of under nutrition:Suffer from mental retardation and infectious diseases.

3. Mal nutrition:

Besides minimum calorie intake we also need proteins, minerals, vitamins, iron and

iodine. Deficiency leads to malnutrition resulting in several diseases.

Effect of mal nutrition:

S.No

1

2

3

4

Deficiency of nutrients

Protein

Iron

Iodine

Vitamin - A

Effects

Growth

Anemia

Goiter

Blindness

rd

India 3 largest producer of crops, nearly 300 million Indians are still under nourished.

World food summit 1996:

The world food summit, 1996 has set the goal to reduce the number of under nourished and

mal nourished people to just half by 2015.

Over grazing:

It is a process of eating the forest vegetation without giving a chance to regenerate.

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Effects of over grazing:

1. Land degradation

over grazing removing the cover of vegetation

exposed soil gets compacted

soil moisture is not available

OG leads to poor, dry and compacted soil.

Land can not be used for further cultivation.

2. Soil erosion:

When the grasses are removed the soil becomes loose and gets eroded by the

action of wind and rain fall.

3. Loss of useful species:

OG affects the plant population and their regenerating capacity. OG replace the plant of

high nutritive value with plant of low nutritive value.

Agriculture:

Agriculture is an art, science and industry of managing the growth of plants animals for human

use. It includes cultivation of the soil, growing and harvesting crops, breeding and raising livestock,

dairying and forestry.

Types of agriculture:

1. Traditional agriculture

2. Modern (or) industrialised agriculture

Traditional agriculture:

Small plot, simple tools, surface water, organic fertilizer and a mixture of crops are enough.

They produce enough food to feed their family and to sell it for their income.

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2. Problems in using pestcides:

First generation pesticide:

Sulphur, arsenic, lead and mercury.

Second generation pesticide:

DDT

Number of side effects:

1. Death of non target organism.

2. Producing new pest - super pest

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3. Bio magnification - Most of the pesticides are non bio degradable, keep on

concentrating in the food chain and it is harmful to human beings.

4. Risk of cancer:

a. It directly acts as carcinogen

b. It indirectly supports immune system.

Water logging:

Land where water stand for most of the year.

Causes of water logging:

1. Excessive water supply

2. Heavy rain

3. Poor drainage

Remedy:

1. Preventing excessive irrigation

2. Subsurface drainage technology

3. Bio drainage like trees like Eucalyptus

Case study:

Pesticides in India:

In Delhi the accumulation of pesticide in the body of mother causes premature delivary and

low birth weight infant.

Pesticides in pepsi and coca cola:

India has reported that pepsi and coca cola companies are selling soft drinks with a pesticide

content 30-40 times higher than EU limits. This damages the nervous system,.

ENERGY RESOURCES:

Energy distribution in the world:

Developed countries like USA and Canada constitute only 5% of the world's population but

consume 25% of the world's available energy. Energy consumed by a person in a developed country

or a single day is equal to energy consumed by a single person in a poor country for one year.

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Developed country GNP increases and energy consumption increases. In the poor country GNP and

energy consumption are less.

DC

EC

PC

GNP

Types of energy resources:

1. Renewable energy resource (or)Non conventional energy resources

2. Non renewable energy resources (or) Conventional energy resources

3.

Merits of renewable energy resources:

1. Unlimited supply

2. Provides energy security.

3. Fits into sustainable development concept.

4. Reliable and the devices are modular in size.

5. Decentralised energy production.

Renewable energy sources:

Energy which can be regenerated

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Solar energy:

Nuclear fusion reaction of sun produces enormous amount of energy. Several techniques are

available for collecting, storing and using solar energy.

Solar cell (or) Photovoltaic cell (or) PV cell:

Solar cell consist of p- type semi conductor (Si doped with B)

And n-type semi conductor(Si doped with P). p-type forms top layer and n-type forms bottom layer..

solar rays fall on the top layer , the electrons fron valence band promoted to the conduction band

which crosses the p-n junction into n-type semi conductor. Potential difference between the two layers

is created which causes flow of electrons.

Solar cell

Uses:

It is used in calculators, electronic watches, street light, water pumps etc.

Solar battery:

Large number of solar cells connected in series is called solar battery. It is used in remote areas

where continuous power supply is a problem.

Solar water heater:

It consist of insulated box painted with black paint with glass lid. Inside the box black painted

copper coil is present. Cold water is allowed to flow, it is heated up and flows out into a storage tank

rom which water is supplied through pipes.

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Wind energy:

Moving air is

called wind. The energy recovered from the force of the wind is called windenergy It's speed is high.

Wind mills:

When a blowing wind strikes the blade of the wind mill, it rotates continuously. And rotational

motion of the blade drives number of machines like water pump, flour mills and electric generators.

Wind farms:

When a large number of mills are installed and joined together in a definite pattern - it forms

wind farm. It produces large amount of electricity.

Condition:

Minimum speed for wind generator is 15 Km/hr

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Advantages:

1. It does not cause air pollution

2. Very cheap

Ocean energy:

Tidal energy (or) Tidal power:

Ocean tides are due to gravitational force of sun and moon which produce enormous amount of

energy. High tides - rise of water in the ocean. Low tides - fall of water in the ocean. Tidal energy

can be used by constructing a tidal barrage. During high tides sea water enters into the reservoirs and

rotates the turbine, produce electricity. During low tides water from reservoir enters into the sea rotate

the turbine produce electricity.

Ocean thermal energy:Temperature difference between surface water and deeper level water in ocean generates

electricity. The energy available due to the difference in temperature of water is called ocean thermal

energy.

Condition:

0

Temperature difference should be 20 C.

Process:

Ammonia is converted into vapours on the surface of warm water, it increases the vapour

ressure which rotate the turbine and generates electricity. Deeper level cold water is pumped to cool

and condense the vapour in to liquid.

Geo thermal energy:

0

Temperature of the earth increases at a of 20 -75 C per/km when we move down the earth.

The energy utilised from the high temperature present inside the earth is called geothermal energy.

Natural geysers:

Hot water or steam comes out of the ground through cracks naturally is called natural geysers.

Artificial geysers:

Artificially a drill hole up to the hot region and by sending a pipe into it. The hot water or

steam is used to rotate the turbine and generate electricity.

Bio mass energy:

Bio mass:

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Organic matter produced by plants or animals used as source of energy

Bio gas:

Mixture of methane, carbondioxide and hydrogen sulphide. Methane is the major constituent. It

is obtained by anerobic fermentation of animal dung (or) plant wastes in the presence of water.

Bio

ermentation of biomass.Fuels obtained by the

ethanol, methanol

Ethanol :

Produced from sugar

Calorific value is less.

Eg

cane.

Methanol:

Obtained from ethanol Calorific value too less.

Gasohol:

Mixture of ethanol and gasoline India trial is going on to use gasohol in cars and buses.

Hydrogen fuel:

Hydrogen produced by pyrolysis, photolysis and electrolysis of water. It has high calorific

value. Non polluting one because the combustion product is water.

Disadvantages:

1. Hydrogen is highly inflammable and explosive.

2. Safe handling is required.

3. Difficult to store and transport.

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Non renewable energy sources:

Energy which can not be regenerated.

Coal:

It is a solid fossil fuel.

Disadvantages:

1. when coal is burnt large amount of CO 2 is released. Which causes global warming.

2. S, N produces toxic gases during burning.

Petroleum:

Crude oil is a liquid consists of more than hundreds of hydrocarbons and small amount of

impurities. The petroleum can be refined by fractional distillation. In the world level 25% of oil

reserves are in Saudi Arabia. At present rate of usage, the world crude oil reserves are expected to get

exhausted in just 40 years.

Liquefied petroleum gases(LPG):

Petroleum gases obtained during FD and cracking can be easily converted into liquid under

high pressure as LPG. It is colourless and odourless gas, but during cylindering mercaptans are added

to detect leakage.

Natural gas:

These are found above oil in oil wells. It is a mixture of methane and other hydrocarbons.

Calorific value is high. There are two types. Dry gas and wet gas.

Nuclear energy:

Dr.H.Bhabha is a father of nuclear power development in India. 10 nuclear reactors are present

in India. It produces 2% of India's electricity. Nuclear energy can be produced by two types of

reactions. Nuclear fission and nuclear fusion.

Nuclear fission;

It is a nuclear change in which heavier nucleus split into lighter nuclei on bombardment of fast

moving neutrons. Large amount of energy is released through chain reaction.

E.g

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Uranium with fast moving neutron gives barium and krypton in addition to three neutrons, in

the second stage it gives nine neutrons and so on. This process of propagation of the reaction by

multiplication is called chain reaction.

Nuclear fission:

It is a nuclear change in which lighter nucleus are combined together at extremely high

0

temperature (1 billion C) to form heavier nucleus and a large amount of energy is released.

E.g

Isotopes of hydrogen combine to form helium molecule.

Case Study:

Wind energy in India:

India generating 1200 MW electricity using the wind energy. Largest wind farm

situated near Kanyakumari in Tamil nadu. It produces 380 MW electricity.

Hydrogen fuel car:

General motar company of china discovered a experimental car ( fuel H2) can produce no

emission only water droplets and vapours come out of the exhaust pipe. This car will be commercially

available by 2010.

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Land resources:

Land is the most important valuable resource for mankind,

It provides food, fibre, medicine.

It is a mixture of inorganic materials and organic materials.

To construct building

Acts as a dustbin for most of the wastes created by the modern society.

Land degradation:

It is a process of deterioration of soil or loss of fertility.

Effects of land degradation:

1. Soil texture and soil structure are destructed.

2. Loss of soil fertility.

3. Loss of valuable nutrients.

4. increase in water logging, salinity, alkalinity and acidity problem.

5. Loss of economic social and biodiversity.

Causes of land degradation:

1. Population:

More land is needed for producing food, fibre and fuel wood. So land is degraded due

to over exploitation.2. Urbanisation:

Urbanisation reduces the agricultural land. Urbanisation leads to deforestation, which inturn

affects millions of plants and animals.

3. Fertilizers and pesticides: It affects fertility of the soil and causes land pollution.

4. Damage of top soil:

Increase in food production generally leads to damage of top soil through nutrient

depletion.

5. Water logging, soil erosion, salination and contamination of the soil with industrial wastes and

cause land degradation.

Soil erosion:

The process of removal of superficial layer of the soil from one place to another is called soil

erosion.

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Harmful effects of soil erosion:

1. Soil fertility decreases due to the loss of top soil layer.

2. Loss of it's ability to hold water and sediments.

3. Sediments run off can pollute water and kill aquatic life.

Types of soil erosion:

1. Normal erosion:

It is caused by gradual removal of top soil by the natural process. The rate of erosion is

less.

2. Accelerated erosion:

It is caused by man made activities. The erosion is much faster than the rate formation

of soil.

Causes of soil erosion:

1. water

water causes soil erosion in the form of rain, run off, rapid flow and wave action.

2. wind:

It is an important climatic agent, which carry away the fine particles of soil creates soil

erosion.

3. Biotic agent:

Over grazing, mining and deforestation are the major biotic agent cause soil erosion.

35% of soil erosion is due to over grazing and 30% is due to deforestation.

4. Land slide:

It causes soil erosion.

5. Construction:

Construction of dams, buildings, roads removes protective vegetal cover and leads to

soil erosion.

Control of soil erosion (or) Soil conservation practices:

The art of soil conservation is based on following basic principles

1. To slow down the water for concentrating and moving down the slope in a narrow path.

2. To slow down the water movement when it flows along the slope.

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3. To encourage more water to enter into the soil.

4. To increase the size of soil particles.

5. Reduction in the wind velocity near the ground by growing vegetation.

Conservational tillage:

The process of mixing the residues from previous crops into the soil by ploughing is called

conservational tillage. It improves soil permeability and increase organic matter, which in turn

improve soil moisture and nutrients.

Organic farming:

Process of increasing organic input to the soil. E.g bio fertilizer

Crop rotation:

Process of growing different crops in successive year on the samew land. It prevents the loss of

ertility of the soil.

Contour Ploughing:

It is very useful areas with low rain fall, i.e placing some furrows to store water, which reduces

runoff and erosion.

Mulching:

Soil is covered with cropl residues and other form of plant litters.

Strip cropping:

Planting of crops in rows to check flow of water.

Terrace farming:

Conversion of steep slopes in to a series of broad terraces which run across the contour. It

reduces soil erosion by controlling run off.

Agroforestry:

Planting crops in between rows of trees or shrubs, that can provide fruits and fuel wood. After

harvesting the crops the soil will not be eroded because trees and shrubs will remain on the soil and

hold the soil particles.

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Wind break:

Trees are planted in lo0ng rows along the boundaryof cultivated lands, which block the wind

and reduces soil erosion.

Desertification:

It is a form of land degradation. It is a progressive destruction or degradation of arid or sen\mi

arid lands to destruct.

Causes:

1. Deforestation

2. Over grazing

3. Over utilisation of water

4. Mining and quarrying

5. Climate change

6. Excessive use of fertilizers and pesticides

Effects of desertification:

80% of productive land in the arid and semi arid regions are converted in to desert. Around 600

million people are suffered by desertification.

Role of an individual in conservation of natural resources:Conservation of energy:

1. Switch off light, fan and other appliances when not in use.

2. Use solar heater for cooking.

3. Dry the cloth in the sun light instead of driers.

4. Use always pressure cookers

5. Grow trees near the house to get cool breeze instead of using AC and ai cooler.

6. Ride bicycle or just walk instead of using scooter for ashort distance.

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Conservation of water:

1. Use minimum water for all domestic purposes.

2. check the water leaks in pipes and repair them properly.

3. Reuse the soapy water, after washing clothes for washing courtyard, carpets etc.

4. Use drip irrigation.

5. Rain water harvesting system should be installed in all the houses.

6. Sewage treatment plant may be installed in all industries and institution.

7. Continuous running of water taps should be avoided.

8. Watering of plants should be done in the evening..

Conservation of soil:

1. Grow different type plants i.e trees, herbs and shrubs.

2. In the irrigation process, using strong flow of water should be avoided.

3. Soil erosion can be prevented by sprinkling irrigation.

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4. Use green manures in the garden.

5. Use mixed cropping.

Conservation of food resources:

1. Cook required amount of food.

2. Don't waste the food, give it to some one before spoiling.

3. Don't store large amount of food grains and protect them from damaging insects.

Conservation of forest:

1. Use non timber product.

2. Plant more trees.

3. Grassing must be controlled

4. Minimise the use of paper and fuel.

5. Avoid the construction of dam, road in the forest areas.

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Equitable use of resources for sustainable life style:

Sustainable development:

Development of healthy environment without damaging natural resources.

Unsustainable development;

Degradation of the environment due to over utilisation of natural resources.

Life style in more developed countries:

22% of world population, 88% of it's natural resources and 85% of total global income.

Consumption is more and pollution is more.

Life style in less developed countries:

78% of world population, 12% of it's natural resources and 15% of total global income.

Consumption is less and pollution is less.

Causes of unsustainability:

Main cause - difference between MDCs and LDCs.

Sustainable life style:

MDCs should have to reduce the utilisation of natural resources, that should have to be

diverted to LDCs. This will reduce the gap between MDCs and LDCs, leads to sustainable

development of the entire world.

QUESTION BANK

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UNIT - I

PART - A

1. Define Environmental studies.

2. Mention the scope and importance of Environmental studies.

3. How forests are useful to mankind?

4. What is mining? Mention the methods of mining.

5. Discuss the problems of over-exploitation of Ground water.

6. What are the methods of flood control?

7. What are the merits of using renewable energy resources?

8. Why alternate energy resources are required?

9. What is soil erosion?

10. Differentiate between renewable & non-renewable energy resources.

11. Mention the advantages & disadvantages of modern agriculture.12. Define Eutrophication.

13. What is meant by sustainable development?

14. What are the major causes of deforestation?

15. Mention the effects of ground water usage?

16. What are the types of minerals?

17. What is nuclear energy?

18. Define sustainable forestry.

19. State the environmental effects of extracting & using mineral resources.

20. State the need for public awareness for solving environmental problems.

PART - B

1. What are conventional energy resources? Discuss about solar energy and Ocean therm

energy.

2. Discuss the major causes & consequences of deforestation?

3. Explain the major impacts of timber extraction and mining.

4. Enumerate the various benefits and drawbacks of constructing dams.

5. What are the uses and over-exploitation of water? Explain with a case-study.

6. What are the environmental impacts of mineral extraction? Explain.

7. Discuss in detail the impacts of over-grazing & agriculture.

8. Explain as an individual how will you conserve natural resources.

9. How will you achieve sustainable life-style by equitable share of resources.10. What are the measures recommended for conservation of natural resources.

11. Explain briefly the various methods of harvesting solar energy.

12. Explain in detail the effects due to pesticides usage in moderns agriculture.

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UNIT II ECOSYSTEMS AND BIODIVERSITY

Concepts of an Ecosystem - Structure and Function of an Ecosystem - Producers,

Consumers and Decomposers - Energy Flow in the Ecosystem - Ecological

Succession - Food Chains, Food Webs and Ecological Pyramids - Introduction,Types, Characteristic Features, Structure and Function of the (A) Forest Ecosystem

(B) Grassland Ecosystem (C) Desert Ecosystem (D) Aquatic Ecosystems (Ponds,

Streams, Lakes, Rivers, Oceans, Estuaries) - Introduction to Biodiversity -

Definition: Genetic, Species and Ecosystem Diversity - Biogeographical

Classification of India - Value of Biodiversity: Consumptive Use, Productive Use,

Social, Ethical, Aesthetic and Option Values - Biodiversity at Global, National and

Local Levels - India as a Mega-Diversity Nation - Hot-Spots of Biodiversity -

Threats to Biodiversity: Habitat Loss, Poaching of Wildlife, Man-Wildlife Conflicts -

endangered and Endemic Species of India - Conservation of Biodiversity: In-Situ and

Ex-Situ conservation of Biodiversity.Field Study of Common Plants, Insects and

Birds.

UNIT II

ECOSYSTEM:

Living organisms cannot be isolated from their non-living environment because the later prov

materials and energy for the survival of the farmer. An ecosystem is therefore defined as a

natural

unctional ecological unit comprising of living organisms and their non-living environment that

interact to form a stable self supporting system .

Eg. Pond, lake, desert, grassland, forest, etc.

ENERGY FLOW IN ECOSYSTEM:

Energy is defined as the capacity to do work. For living organisms, it is the basic force responsible for

running all the metabolic activities. The flow of energy from producer level to top consumer level is

called energy flow.

The flow of energy in an ecosystem is unidirectional. It flows from producer level to consumer level

and never in the reverse direction.

The process of energy flow involves transfer of energy from autotrophy to various componen

of

heterotrophy and help in maintaining bio diversity. The main source of energy in the ecosy

issunlight. About 80% of energy is lost during flow of energy from one tropic level to the next one.

Sun Producer Herbivores Carnivores Top carnivores Decomp

FOOD CHAIN

Plants by photosynthesis convert solar energy into protoplasm. Small herbivores consume the

vegetable matter and convert into animal matter which in turn eaten by large carnivores.This

sequence of eaten and being eaten , produces transfer of food energy known as food chain.

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Producers

(Plants)

Consumer I order

(Deer)

Consumer II order

(Tiger, Lion)

Decomposers

(Bacteria, fungi)

FOOD WEB:

The food relationship between various organisms is being depicted by linking all the possible prey and

redators of different food level. In an ecosystem linking of feeding habit relations will provide a food

web.

Grass

Mouse

Rabbit

Grasshopper

snake

Lizard

Hawk

ECOLOGICAL PYRAMIDS:

The energy biomass and number of organisms gradually decreases from the producer level tothe

consumer level. The total mass of herbivores in an ecosystem will generally be less than t

total

mass of plants. Similarly the total mass of carnivores will be less than the total mass of herbivores.

The graphical representation of the number, biomass and energy of various energy levels is

called

ecological pyramid. In any ecological pyramid the producer forms the base and the successive levels

orm the tires which can make the apex.

Types of ecological pyramids:

a) pyramid of numbers

b) pyramid of biomass

c) pyramid of energyEg. Grassland ecosystem - pyramid of number - upright pyramid

birds

insects

Worms

rass

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Parasite ecosystem - pyramid of number - inverted pyramid

Bacteria, fungi

Parasites

Birds

Tree

MAJOR TYPES OF ECOSYSTEMS

FOREST ECOSYSTEM

Definition: It is a natural ecosystem consisting of dense growth of trees and wild animals

Types: tropical - deciduous, evergreen, wet green

Littoral and swamps

Sub tropical

Characteristics:

Abiotic: soil, sun light, temperature etc

Biotic : forest trees, shrubs and animals

Structure:

Producer

Consumer

:

:

Decomposers :

Functional components:

trees and shrubs

Primary - elephants, deer etc.

Secondary - snakes, birds, lizards etc

Tertiary - lions, tigers etc

ungi, bacteria

Ecological pyramids (upright)

lions

lizards

deers

trees

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AQUATIC ECOSYSTEM

Definition:

Deals with water bodies and biotic communities present in them-Classified as fresh water and

marine ecosystems. Fresh water systems are classified as lentic and lotic ecosystems.

Types:

1. Pond ecosystem: Small fresh water ecosystem - seasonal in nature - organisms: algae, aquatic

plants, insects, fishes etc. Ponds are very often exposed to anthropogenic pressure like cloth

washing, bathing, cattle bathing, swimming etc.

2. Lake ecosystem: Big fresh water ecosystem - Zonation or stratification, especially du

summer is a common one.

Top layer - shallow, warm, prone to anthropogenic activities - Littoral zone

Second layer - enough sunlight, high primary productivity - Limnetic zone

Third layer - very poor or no sunlight - Profundal zone

Eg. Dal lake in Srinagar, Naini lake in Nainital

Organisms: planktons - phytoplankton eg. Algae - zooplankton eg. Rotifers

Nektons - that swims in water eg. Fishes

Neustons - that float on the surface of water

Benthos - that attached to sediments eg. Snails

Types of lakes : Many types- oligotrophic lakes - with less nutrient content - eutrophic lakes -

with very high nutrient content due to fertilizer contamination - desert salt lakes - that contains

high saline water due to over evaporation - volcanic lakes - formed by water emitted

rom

magma due to volcanic eruptions - dystrophic lakes - that contains highly acidic wate

(lowpH) - endemic lakes - lakes that contain many endemic species - etc.

3. Streams: fresh water ecosystem where water current plays a major role. Oxygen and nutrient

content are uniform. Stream organisms have to face extreme difference in climatic conditions

but they do not suffer from oxygen deficiency as pond and lake organisms. This is b

large surface area of running water provides more oxygen supply. The animals hav

very

narrow range of tolerance towards oxygen deficiency. Thus stream are worst victims

industrial pollution.

River ecosystem: large streams flowing from mountain highlands are rivers.

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Three phases: 1. mountain highlands - rushing down water fall of water - large qua

of

dissolved oxygen - plants attached to rocks and fishes that require more oxygen are found. 2.

Second phase - gentle slopes of hills - warmer - supports the growth of plants and fishes that

require less oxygen are seen. 3. Third phase: river shapes the land - lots of silts, nutrients arebrought - deposited in plains and delta - very rich in biodiversity.

4. Oceans: Gigantic reservoirs of water covering >70% of earth surface - 2,50,000 spe

huge variety of sea products, drugs etc. - provide Fe, Mg, oils, natural gas, sand etc. - major

sinks of carbon di oxide - regulate biochemical cycles.

Two zones: coastal zone - warm, nutrient rich, shallow - high sunlight - high primar

productivity. Open sea - away from continental shelf - vertically divided in to 3 zones.

1. euphotic zone - abundant sunlight 2. bathyal zone - dim sunlight 3. abyssal zone -

dark zone - world's largest ecological unit.

Estuary: coastal area where river meet ocean - strongly affected by tidal actions - very rich in

nutrients - very rich in biodiversity also - organisms are highly tolerant - many specieendemic - high food productivity - however to be protected from pollution.

Characteristics:

Structural Components:

Abiotic: pH, nutrients, D.O, temp, climatic conditions, etc.

Biotic: Phytoplankton, fishes, snails insects, birds, etc.

Functional components:

Ecological pyramid

birds

fishes

Worms,insects

hytoplankton

Energy flow:

Phytoplankton Insects small fishes huge fishes

Decomposition

sediments

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GRASSLAND ECOSYSTEM:

dominated by grass - few shrubs and trees are also found - rainfall average but erratic - overgrazingleads to desertification.

Three types - depending on the climate

1. Tropical grass lands - found near the boarders of tropical rain forests. Eg. Savannas in Africa.

Animals - Zebra, giraffes etc. - fires are common in dry seasons - termite mounds produce

methane - leads to fire - high in photosynthesis - deliberate burning leads to release of high

CO 2 - global warming.2. Temperate grasslands - flat and gentle slopes of hills. Very cold winter and very hot summer -

dry summer fires do not allow shrubs and trees to grow - soil is quite fertile - cleaned for

agriculture.3. Polar grasslands - found in arctic polar region - organism - arctic wolf, fox, etc. - A thick

layer of ice remains frozen under the soil surface throughout the year - known as permafrost -

summer insects and birds appear.

Components:

Structural Components:

Abiotic: soil pH, nutrients, soil moisture, temp, climatic conditions, etc.

Biotic: grass, caterpillar, butterfly, worms, insects, birds, etc.

Functional components:

Ecological pyramid

birds

insects

Worms

rass

Energy flow:

Grass worms Insects small birds huge birds

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Decomposition

sediments

BIODIVERSITY

Biodiversity is the abbreviated word for biological diversity (bio-life or living organismdiversity-variety). Thus biodiversity is the total variety of life on our planet, the total number of

races, varieties and species. The sum of total of various types of microbes, plants and

animals

(producers, consumers and decomposers) in a system.

Biomes can be considered life zones, environment with similar climatic, topographic and

conditions and roughly comparable biological communities (Eg. Grassland, forest). The bio

shelter an astounding variety of living organisms (from driest desert to dripping rain forest, from

highest mountain to deepest ocean trenches, life occurs in a marvelous spectrum of size,

shape,

colour and inter relationship). The variety of living organisms, the biodiversity, makes the world

beautiful.There are 1.4 million species known presently. But based on new discoveries, by resear

expeditions, mainly in tropics, taxonomists estimate there are between 3-50 million different

species may be alive today. Insects make up more than one half of all known species

may

comprise more than 90% of all species on earth.

The concept of biodiversity may be analyzed in 3 different levels. They are

1 ecosystem diversity

2 species diversity

3 genetic diversity

Ecosystem or ecological diversity means the richness and complexity of a biological community,including tropic levels, ecological processes (which capture energy), food webs and material

recycling.

Species diversity describes the number of kinds of organisms within individual communitie

ecosystems.

Genetic diversity is a measure of the variety of versions of same gene within individual species.

Biodiversity Hotspots:

Most of the world's biodiversity are near the equator especially tropical rain forest and coral reefs.

Of all the world's species, only 10-15% live in North America and Europe.

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The Malaysian Peninsula, for instance, has at least 8000 species of flowing plants, while Britain,

with an area twice as large, has only 1400 species. South America has 200 000 species of plants.

Areas isolated by water, desert or mountain can also have high conc. of unique speciesand

biodiversity. New Zealand, South Africa and California are all mid-latitude area isolated

barriers that prevent mixing up of biological communities from other region and produce

rich,

unusual collection of species.

Significance of Biodiversity:

Biosphere is a life supporting system to the human race. Each species in the biosphere has its ownsignificance.

It is the combination of different organisms that enables the biosphere to sustain human race.

Biodiversity is vital for a healthy biosphere.

Biodiversity is must for the stability and proper functioning of the biosphere.

Besides these biodiversity is so important due to having consumptive use values, productive

values, social values, ethical values and aesthetic values.

Benefits of biodiversity:

We benefit from other organism in many ways. Even insignificant organisms can p

irreplaceable roles in ecological systems or the source of genes or drugs that someday

becomeindispensable.

Food: Many wild plant species could make important contributions to human food suppliers either

as they are or as a source of material to improve domestic crops. About 80,000 edible plants could

be used by human.

Drugs and medicine: Living organisms provides many useful drugs and medicines. The United

Nations Development Programme derived from developing world plants, animals and microbes to

be more than $30 billion per year.

Eg. For natural medicinal products

Penicillin - fungus is the source - Antibiotic

Quinine - chincona bark - Malaria treatment

Morphine - poppy bark - AnalgesicTwenty years before, once the drugs were not introduced, childhood leukemia was fatal. Now the

remission rate for childhood leukemia is 99%.

Ecological benefits:

Human life is inextricably linked to ecological services provided by other organisms.

formation, waste disposal, air and water purification, solar energy absorption, nutrient cycling and

food production all depend on biodiversity. In many environments, high diversity may h

biological communities to withstand environmental stress better and to recover more quickly than

those with fewer species.

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Threats to biodiversity:

Due to

Habitat loss

Deforestation activities (cutting trees for timber, removal of medicinal plants) Production of hybrid seeds requires wild plants as raw material, farmers prefer h

reeds, many plant species become extinct

Increase in the production of pharmaceutical companies made several number of medicinal

plants and species on the verge of extinction.

Removal of forest-cover for road laying and also due to soil erosion

Illegal trade of wild life

Population explosion, construction of dam, discharge of industrial effluents

pesticides.

Poaching of wild life

Due to poaching, illegal trade and smuggling activities most of our valuable fauna are under threat

organised crime has moved into illegal wild life smuggling because of huge profit Eg. Tiger, Deer

- for hides, Rhinoceros - for horns, Elephant - for ivory tusk, Sea Horse, Star turtle -

to

foreign market.

(Extinction, the elimination of species, is a normal process of the natural world. Species die put

and are replaced by others as part of evolutionary change.

Human caused reduction: The climate change caused by our release of green house gases in the

atm. could have catastrophic effects. Human disturbance of natural habitat is the largest

cause pf loss of biological diversity. Woodlands and grasslands are converted now use about 10%of the world's land surface for crop production and about twice the amount for pasture

grasslands.)

Hunting: Over harvesting is responsible for depletion or extinction of many species.

Eg. The American passenger pigeon was the world's most abundant bird. In spite of

vast

population, market hunting and habitat destruction caused the entire population to crash with in 20

years.

Fragmentation

Habitat fragmentation reduces the biodiversity because many animals like bears and large

require large territories to subsist. Some forest birds reproduce only in deep forest or hab

ar

from human settlement. A large island for example, can support more individuals of given species

and therefore less likely to suffer extinction due to genetic problems and natural catastrophes.

Commercial products:

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Smuggling of fuels, hides, horns and folk medicines also affect the biodiversity in an

abrupt

manner.

Conservation of biodiversity

In general biodiversity is generally disturbed by human activities. To solve the problems

is

essential to protect our bio diversity by two ways.

1. In-situ or on-site conversion

2. Ex-situ conservation

In-situ conservation:

Conservation of species in its natural habitat, in place where the species normally occurs The strategy involves establishing small or large protected areas, called protected areas

Today in world, there are 9800 protected areas and 1500 national parks

Methods:

1.

2.

3.

Nature or biosphere reserves (Eg) Nilgiri Bio reserve

national parks and sanctuaries (Eg) Mudumalai, vedanthangal

on farm and home garden conservation for plants, vegetables and fruits to

maintaintraditional crop varieties.

Ex- situ conservation:

It involves maintenance and breeding of endangered plant and animal species under partially or

wholly controlled conditions in zoos, gardens and laboratories

The crucial issue for conservation is to identify those species which are more at ris

of

extinction.

Methods:1.

2.

3.

4.5.

long term captive breeding

shortage term propagation and release

animal translocation and re introductions

seed bankreproductive technology

(i) embryo transfer technology

(ii) cloning

Biodiversity and National Environmental law:

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All environmental problems are regional in nature but their effects arelobal.

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Hence

environmental problems cane be resolved only by extensive co operation among nations. Laws

serve to achieve global objective of environmental protection.

Indian law for conservation of biodiversity:

The wild species of the group and other related species constitute a rich gene pool in India. The

overnment of India has enacted laws for the conservation of biological diversity.

The habitat protection laws:

This includes species protection laws and habitat protection laws which indirectly protect

and

conserve the biological diversity and its components.

The wild life (protection) Act 1972: Enacted

1. to protect wild animals and birds which are in the verge of extinction

2. to protect biological diversity in particular and environmental protection in general.

3. for the protection of wild animals and birds and for all other matters connected t

of or

ancillary and incidental there to.Biosphere Reserve and the wild life (protection) Act 1972:

Biosphere reserves are complementary to the existing network of national parks and sanctuaries,

this act is enacted to protect biosphere.

UNIT-II

PART-A

1. Define Ecology?

2. Define Eco-System with an example?

3. What are the structural components of an Ecosystem?

4. Differentiate between Food Chain and Food Web?5. What are Ecological Pyramids. Give examples.

6. What are Biochemical cycles. Explain their importance?

7. What is the significance of Ecological pyramids?

8. Discuss about the prime characteristics of

a.Forest Ecosystem

b.Grassland Ecosystem

c.Desert Ecosystem

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d.Aquatic Ecosystem

9. Differentiate between biodiversity and ecosystem biodiversity.

10. What are hotspots of biodiversity?

11. What are endangered species? Give examples.

12. Explain the necessity to conserve biodiversity.13. Bring few methods to conserve biodiversity.

14. Bring out the classification of aquatic ecosystem.

15. Explain ecological; pyramids with respect to pond ecosystem.

16. What is ecosystem diversity.

17. Bring out the Bio-geographical classification of India.

18. What is biodiversity and its significance.

19. Explain biosphere.

20. Explain threatened species.

PART-B

1. Explain the components, characteristics and biodiversity of Forest ecosystem.

2. Explain the structure and functional features of Aquatic ecosystem.

3. What are trophic levels? Explain the flow of energy and minerals in ecosystem.

4. Explain the two models of energy flow in an ecosystem.5. Discuss the value of biodiversity.

5. Explain Carbon and Nitrogen cycles.

6. Explain the Sulphur and Phosphorus cycles.

7. What are the threats faced by biodiversity. What are the solutions for the threats.

8. Explain In-situ and Ex-situ conservation of biodiversity.(or) What are the measures recommended

or conservation of biodiversity.

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UNIT III ENVIRONMENTAL POLLUTION

Definition - Causes, Effects and Control Measures of:- (A) Air Pollution (B) Water

Pollution (C) Soil Pollution (D) Marine Pollution (E) Noise Pollution (F) Thermal

Pollution (G) Nuclear Hazards - Solid Waste Management:- Causes, Effects and

Control Measures of Urban and Industrial Wastes - Role of an Individual in

Prevention of Pollution - Pollution Case Studies - disaster Management:- Floods,

Earthquake, Cyclone and Landslides.

UNIT-III

ENVIRONMENTAL POLLUTIONAIR POLLUTION

Air pollution is defined as the presence of one (or) more contaminants like dust, smoke, mist and

odour in the atmosphere which causes damage to plants, animals and human beings.

Composition of air: N- 78%, O 2 - 21%, Argon

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Burning fuel in the kitchens, cigarette smoke liberates pollutants like CO, SO2.

Common Air pollutants sources and their effects

CO - formed by the incomplete combustion of carbon containing fuels.

2C + O2------------>

2CO

Human Sources - Cigarette smoking, burning fossil fuels. 77% Co comes from motor vehicle

exhaust.

Health Effect- Reacts with hemoglobin and reduces the ability of to carry O 2 to body cells and tissues,

which causes headaches and anemia.

NO 2 - It gives photochemical smog. In atmosphere it reacts with moisture to form HNO3. No 2 +

Moisture ------> HNO3

Human sources: Fossil fuel burning in motor vehicles and power industrial plants.Effect Health, Lung irritation and damage

Environment effect: HNO 3 corrode metals and eat away stone on buildings, statues, NO 2 damages

abrics.

SO 2- Formed mostly by the combustion of sulphur containing fossil fuels like coal and oil. is

converted to H 2SO 4 in the atmosphere. It is major component of acid deposition.

Human Source- Coal burning in power plants and industrial process.

Health effects- Breathing problems.

Environment effect - Reduce visibility, H2So 4 damages trees, soil and aquatic life.

Suspended particulate Matter (SPM) -It includes varieties of particles and droplets.

Human Sources - Burning coal in power and industrial plants. Burning diesel and other in

vehicle, agriculture, unpaved roads construction.

Health Effect - Nose and throat irritation, lung damage, asthma, reproductive problems and cancer.

Environment effect - Reduce visibility, acid deposition & H2SO 4 droplets damage trees.

O -3H ighly reactive irritating gas in the troposphere. It is major component of photo chemical smog.

Human Source- Chemical reactions with volatile organic compounds and nitrogen oxides.

Environment effect - Moderates the climate.

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Photochemical smog: Any chemical reaction activated by light is called photochemical reaction

Photochemical smog is a mixture of more than 100 primary and secondary pollutants formed under the

influence of sunlight. Its formation begins inside automobile engines and the boilers in coal burning

ower and industrial plants.

Health Effect - Breathing problems, cough, ENT irritation, heart diseases etc.,

Environment effect - Smog can reduce visibility.

7 Lead - Solid toxic metal and its components emitted into the atmosphere as a particulate matters.

Human Source- Paint, lead manufacture, storage batteries, leaded petrol.

Health Effect - Mental retardness (in children) digestive and other health problems. Some l

containing chemicals causes cancer in test animals.

Environment effect - Can harm wild life.

Controlling air Pollution

Controlling at the sources:

1.

2.

4.

5.

3.

Use only unleaded petrol

Use fuels that have low sulphurs and ash containing.

Plant trees along busy streets because they remove particulates and CO and absorb noise

Industries and waste disposal should be outside the city area.

Use catalytic converters to control the emission of CO and hydrocarbon.

Control Measures in industries:

1.

2.

3.

4.

Emission rates should be restricted to permissible levels in all industries.

Air pollution control equipment should be incorporated in plant layout

Monitering of the atmosphere for the pollutants should be carried out continuously to know the emission levels.

Scrubber, cyclone separator, bag house filter and electrostatic precipitators must be used in manufacturing

rocess to retain harmful materials that must be disposed of safely.

5. The disposal of the collected air pollutants are equally important for controlling air pollution.

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WATER POLLUTION

The alternation in physical, chemical & biological characteristics of water which causes

harmful effects on humans and aquatic life.

The major pollutants are sewage, effluents, bacteria.

Infections Agents: Bacteria, viruses, protozoa, parasitic worms

Human Source- Human and animal works

Health Effect - Variety of diseases.

Oxygen demanding wastes: Organic wastes, such as animal manure & Plant debris that are

decomposed by aerobic bacteria.

Human Source- Sewage, animal feedlots, paper mills, food processing facilities.

Health Effect - Depletion of dissolved O 2 in water. This causes death of aquatic life.

Inorganic Chemical water soluble chemicals like acids. Compounds o