63816326 environmental science and engineering lecture notes edited

7/28/2019 63816326 Environmental Science and Engineering Lecture Notes EDITED

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ENVIRONMENT, ECOSYSTEM AND BIODIVERSITY

DEFINITION, SCOPE AND IMPORTANCE

Environmental science is the study of nature and the facts about environment.Basically environment can be defined as all the social, economical, physical & chemicalfactors that surrounds man (or) all abiotic and biotic components around man-all livingand non living things surrounds man.

Environment Components can be divided into biotic and abiotic

components.

According to ancient man the environment was the Panchaboodhas (i.e) air, water, land, skyand energy. The human were disciples of nature.

They were able to protect themselves from harmful one and protect the others. Butaccording to modern man the env. is only air land and water. Exploitation of various earthresources to satisfy the increasing needs of human population has resulted in 1) depletion

of various resources of earth 2) pollution.

Principles of environmentaleducation:

Examine the major environmental issues

discover the root cause

develop problem solving skills

promote co-operation in solving problems

emphasis active participation in prevention and solution to problems.

Scope of environmental science:

Studying the interrelationship between the components of env.

Carrying out impact analysis and env. Audit

Preventing pollution from existing and new industries

Stopping the use of biological and nuclear weapons

Managing unpredictable disasters etc.

Public awareness:

Environmental Pollution or problems cannot be solved by mere laws. Public participationis an important aspect which serves the environmental Protection.

Public awareness of environmental Is at infant stage

30-40% of public of developing country are aware of environmental. Problems butthey do not bother about it.

Ignorance and incomplete knowledge has lead to misconceptions


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Development and improvement in std. of living has lead to seriousenvironmental disasters

Debate on environmental Issues are treated as anti-developmental

Reasons for environmental Ignorance:

science, technology and economics failed to integrate the knowledge on environmentalAspects in curriculum

the decision makers do not process environmental Angle of decision making

consideration of economic growth, poverty eradication has lead to environmentalDegradation

only few developmental activities are made considering the environmental Aspects.

Need For Public Awareness:

The United Nations Conference on Environment and Development held at Reo deJaneiro in 1992 (popularly known as Earth Summit) and world summit on sustainabledevelopment at Johannesburg in 2002, have highlighted the key issues of globalenvironmental concern. They have attracted the attention of people.

Any government at its own cannot achieve the goals of clear environment until thepublic participate in action. Public participation is possible only when the public is awareabout the ecological and environmental issues. Eg. Ban- the littering of polythene.

Methods to propagate environmental Awareness:

1. Among students through education introducing environmental studies in the curriculum.

2. Among public through mass media- environmental programmmes through TV, radio etc.

3. Among decision makers, planners, leaders etc.

Role of NGOs

1. Advise the government in interacting with ground level people

2. Organize public meetings to create environmental awareness

Eg. Recent report ofcentre for science and environment on permissible limits of pesticidesin cola drinks.

Public awareness is needed in the area

1. study of natural resources-conservation and management

2. ecology and biodiversity conservation

3. environmental Pollution and prevention

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4. social issues related to development andenvironment

5. human population and environment.

Concept Of Ecosystem:

Living organisms cannot be isolated from their non-living environment because thelater provides materials and energy for the survival of the farmer. An ecosyst em is thereforedefined as a natural functional ecological unit comprising of living organisms and theirnon-living environment that interact to form a stable self supporting system .

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

Ecosystems

Ecology earnest Haeckal- 1869 derived from oikos home , logy study

-deals with the study of organisms in their natural home interacting with their surroundings.

Ecosystem Tansley (1935) self regulating group of biotic communities of

speciesinteracting with one another and with their non-living environment exchanging energy and

matter

Ecosystem characteristics

Structural features composition and organization of biological communities and

abiotic components constitute Structure of EcosystemBiotic structure Plants , animals , microorganisms form biotic components

nutritional behavior and status in the ecosystem producers or consumers how do they gettheir food.

Structure of Ecosystem

1. Abiotic or non-living components or physicalcomponents

2. Biotic or Livingcomponents

3. Energy components.

Abiotic Components:

Abiotic components enter the body of living directly or indirectly take partin metabolic activities and return to environment.

Abiotic components are asfollows

1. Atmosphere The cover of air that envelopes the earth is known as atmosphere.

Compostion


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Nitrogen-78%, oxygen- 2%, other gases- 1%2. Lithosphere or Interior of Earth Solid Earth Radius 6371- density-5.5

3. Hydrosphere 97% earths water is in oceans Fresh water 3%.

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Structure of Atmosphere:

Five Layers

1. Troposphere lower portion extends from 0-18 kms, temperature-2. Stratosphere -18- 50 kms- Temperature (-2C to -56C )- Ozone layer3. Mesosphere- extends from 50-85 kms- Temperature drops to (-95C)4. Ionosphere or Thermosphere extends up to 500 kms. Temperature raises up to 1200C5. Exosphere extends up to 1600 km- temperature very high due to solar radiation.

Functions of Atmosphere:

It maintains heat balance on the earth by absorbing IR

radiation. Oxygen support life on living organism.

Co2 - essential for photosynthetic activity of

plants. N2 - essential nutrient for plant growth.

Interior of Earth or

Lithosphere: Three major

Zones

1. Crust top most layer- solid thickness 30 40 Km in continents and 5 6 km in oceans.Rocks of the earth crust 3 types Igneous , Sedimentary,

Metamorphic.

2. Mantle average density 3.3 Thickness 2860 density increases with depth.3. Core (outer core solid , inner core liquid). depth 2900 km from the surface of the

earth density -12 not exact composition.Functions of Lithosphere:

1. It is home for human beings and wild life.

2. It is store house of minerals and organic matter.

Functions of Ecosystems

Ecosystem characteristics

Structural features composition and organization of biological communities andabiotic components constitute Structure of Ecosystem

Biotic structure Plants , animals , microorganisms form biotic components nutritionalbehavior and status in the ecosystem producers or consumers how do they get their food.

Producers Photosynthesis photoautotroph (auto self, photo-

light) Chemotrops or Chemosynthetic organisms Chemicals

Consumers feeding upon other organisms


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Types Herbivores Plant eating animals primary consumers Eg ; rabbit

Carnivores Feed on consumers Secondary Consumers - feed on other carnivores Tertiary/ Consumers.

Omnivores feed on both plants and animals eg. Humans, rat, fox.

Detritivores - (Detritus feeder or Saprotrophs ) feed on dead on organisms or decomposedmatter eg; beetles, termites,ants , crabs, earthworms.

Decomposers nutrition breaking down in to complex organic molecules to simpler organicorganic compounds bacteria and fungi.

Abiotic Structure. physical and chemical components of an ecosystem.

Physical factors sunlight , temperature ,annual rainfall, soil type, water availability, watercurrents etc. strong influence on the ecosystem.

Chemical factors; major essential nutrients C, N, P, H, O, S.

Biotic Components Abiotic components and viceversa linked through energy flow,matter cyling.

Functional Attributes.

1. Food chain, Food web and trophic structure.2. Energy flow3. Cycling of Nutrients (Biogeochemical cycles)4. Primary and secondary production5. Ecosystem development programme

Food Chains

- Sequence of eating and being eaten in an ecosystem.

Grass Grasshopper Frog snake Hawk

(Grassland Ecosystem)

Grazing food chains Starts with green plants.

Grass Rabbit Fox

Phytoplanktons Zooplanktons Small fish Carnivores (fish)

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Food Web

- Network of food Chains

ENERGY FLOW IN ECOSYSTEM:

Energy is defined as the capacity to do work. For living organisms, it is the basic forceresponsible for running all the metabolic activities. The flow of energy from producer levelto top consumer level is called energy flow.

The flow of energy in an ecosystem is unidirectional. It flows from producer level toconsumer level and never in the reverse direction.

The process of energy flow involves transfer of energy from autotrophs to various componentsof heterotrophs and help in maintaining bio diversity. The main source of energy in theecosystem is sunlight. About 80% of energy is lost during flow of energy from one trophiclevel to the next one.

Sun Producer Herbivores Carnivores Top carnivores Decomposers

ECOLOGICAL SUCCESSION

FOOD CHAIN

Plants by photosynthesis convert solar energy into protoplasm. Small herbivores consumethe 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.

Producers Consumer I order Consumer II order Decomposers(Plants) (Deer) (Tiger, Lion) (Bacteria, fungi)FOOD WEB:

The food relationship between various organisms is being depicted by linking all the possibleprey and predators of different food level. In an ecosystem linking of feeding habit relationswill provide a food web.

Mouse snake

Grass Rabbit Hawk

Grasshopper Lizard

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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 thanthe 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 ofvarious energy levels is called ecological pyramid. In any ecological pyramid the producerforms the base and the successive levels form the tires which can make the apex.

Types of ecologicalpyramids:

a) pyramid of numbersb) pyramid of biomassc) pyramid of energy

Eg. Grassland ecosystem pyramid of number uprightpyramid

birds

insect

s

Worm

s

grass

Parasite ecosystem pyramid of number inverted pyramid

Bacteria,fungi

Parasites

Birds


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Tree

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MAJOR TYPES OF ECOSYSTEMS

a. 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 : trees and shrubs

Consumer : Primary elephants, deer etc.

Secondary snakes, birds, lizards etc

Tertiary lions, tigers etc

Decomposers : fungi, bacteria

Functional components:

Ecological pyramids

(upright)

lions

lizard

s

deer

s

trees


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GRASSLAND ECOSYSTEM:

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

Three typesdepending on the

climate

1. Tropical grass lands found near the boarders of tropical rain forests. Eg. Savannasin Africa. Animals Zebra, giraffes etc. firesare common in dry seasons termite mounds produce methane leads to fire highin photosynthesis deliberate burning leads to release of high CO2 global warming.

2. Temperate grasslands flat and gentle slopes of hills. Very cold winter and very hotsummer - 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 knownas 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

grass

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Energy flow:

Grass worms Insects small birds huge birds

Decomposition

sediments

c. DESERT ECOSYSTEM

Types:

1. tropical desert-found in Africa-Sahara and Rajasthan Thar

2. temperate desert-south California-Majave

3. cold desert-China-Gobi desert

Characteristics:

1. Air is dry

2. Climate is hot

3. Annual rainfall is less than 25 cm

4. Vegetation is poor

d.AQUATIC ECOSYSTEM

Definition:

Deals with water bodies and biotic communities present in them-Classified as freshwater 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 toanthropogenic pressure like cloth washing, bathing, cattle bathing, swimming etc.

2. Lake ecosystem: Big fresh water ecosystem Zonation or stratification,especially during summer is a common one.

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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 inNainital

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 desertsalt lakes that contains high saline water due to over evaporation volcanic lakes formed by water emitted from magma due to volcanic eruptions dystrophic lakes that contains highly acidic water (low pH) endemic lakes lakes that contain manyendemic species etc.

3. Streams: fresh water ecosystem where water current plays a major role. Oxygen andnutrient content are uniform. Stream organisms have to face extreme difference inclimatic conditions but they do not suffer from oxygen deficiency as pond and lakeorganisms. This is because large surface area of running water provides more oxygensupply. The animals have very narrow range of tolerance towards oxygendeficiency. Thus stream are worst victims of industrial pollution.River ecosystem: large streams flowing from mountain highlands arerivers.

Three phases: 1. mountain highlands rushing down water fall of water largequantity of dissolved oxygen plants attached to rocks and fishes that require moreoxygen are found. 2. Second phase gentle slopes of hills warmer supports thegrowth of plants and fishes that require less oxygen are seen. 3. Third phase: rivershapes the land lots of silts, nutrients are brought deposited in plains and delta very rich in biodiversity.

4. Oceans: Gigantic reservoirs of water covering >70% of earth surface 2,50,000 species huge variety of sea products, drugs etc. provide Fe, Mg, oils, natural gas, sand etc.major sinks of carbon di oxide regulate biochemicalcycles.

Two zones: c o a s t a l z o n e warm, nutrient rich, shallow high sunlight highprimary productivity. Op e n s e a away from continental shelf vertically

divided in to 3 zones. 1. euphotic zone abundant sunlight 2. bathyal zone


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dim sunlight 3. abyssal zone dark zone worlds 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 species are endemic high food productivity however to be protected frompollution.

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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,

phytoplankton

Energy flow:

Phytoplankton Insects small fishes huge fishes

Decomposition

sedimentsINTRODUCTION TO BIODIVERSITY

Biodiversity is the abbreviated word for biological diversity (bio -life or livingorganisms, diversity-variety). Thus biodiversity is the total variety of life on our planet, thetotal number of races, varieties and species. The sum of total of various types ofmicrobes, plants and animals (producers, consumers and decomposers) in a system.

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biosphere.

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Besides these biodiversity is so important due to having consumptive use values,productive use values, social values, ethical values and aesthetic values.

Benefits of biodiversity:

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

play irreplaceable roles in ecological systems or the source of genes or drugs thatsomeday become indispensable.

Food: Many wild plant species could make important contributions to human foodsuppliers either as they are or as a source of material to improve domestic crops. About80,000 edible plants could be used by human.

Drugs and medicine: Living organisms provides many useful drugs and medicines. TheUnited Nations Development Programme derived from developing world plants, animalsand microbes to be more than $30 billion per year.

Eg. For natural medicinalproducts

Penicillin fungus is the source

Antibiotic Quinine chincona bark -

Malaria treatment Morphine poppy bark

Analgesic

Twenty 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.Soil formation, waste disposal, air and water purificat ion, solar energy absorption,nutrient cycling and food production all depend on biodiversity. In manyenvironments, high diversity may help biological communities to withstandenvironmental stress better and to recover more quickly than those with fewer species.

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

hybrid 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 use ofpesticides.


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Poaching of wild lifeDue to poaching, illegal trade and smuggling activities most of our valuable fauna areunder

threat organised crime has moved into illegal wild life smuggling because of huge profitEg. Tiger, Deer for hides, Rhinoceros for horns, Elephant for ivory tusk, Sea Horse,

Star turtle sold to foreign market.

(Extinction, the elimination of species, is a normal process of the natural world. Speciesdie put and are replaced by others as part of evolutionary change.

Human caused reduction: The climate change caused by our release of green house gasesin the atm. could have catastrophic effects. Human disturbance of natural habitat is thelargest single cause pf loss of biological diversity. Woodlands and grasslands are convertednow use about 10% of the worlds land surface for crop production and about twice theamount for pasture and grasslands.)

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

species.

Eg. The American passenger pigeon was the worlds most abundant bird. In spite ofthis vast population, market hunting and habitat destruction caused the entire population tocrash with in 20 years.

Fragmentation;Habitat fragmentation reduces the biodiversity because many animals like bears a

nd large cats require large territories to subsist. Some forest birds reproduce only in deepforest or habitat far from human settlement. A large island for example, cansupport more individuals of given species and therefore less likely to suffer extinct iondue to genetic problems and natural catastrophes.

Commercial products: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 theproblems, it is essential to protect our bio diversity by two ways.

1. In-situ or on-site conversion2. Ex-situ conservation

In-situconservation:

Conservation of species in its natural habitat, in place where the species normallyoccurs

The strategy involves establishing small or large protected areas, called protectedareas Today in world, there are 9800 protected areas and 1500 nationalparks


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Methods:

1. Nature or biosphere reserves (Eg) Nilgiri Bio reserve2. national parks and sanctuaries (Eg) Mudumalai, vedanthangal3. on farm and home garden conservation for plants, vegetables and fruits to

maintain traditional cropvarieties. Ex- situ conservation:

It involves maintenance and breeding of endangered plant and animal species underpartially or wholly controlled condit ions in zoos, gardens and laboratories The crucial issue for conservation is to identify those species which are more at risk of

extinction.Methods:

1. long term captive breeding2. shortage term propagation and release3. animal translocation and re introductions

4. seed bank 5. reproductive technology

(i) embryo transfer technology(ii) cloning

Review questions:

1. Define Environmental science

Environmental science is the study of the environment, its biotic and abiotic componentsand their interrelationships.

2. What are the important components of

environment? Abiotic or non-living components

Biotic or living component

Energy component

3. What are the processes involved in hydrological cycle?

Continuous evaporation, transpiration, precipitation of surface run off and ground water

4. Define biogeochemical cycle. Give example.

The continuous circulation of all the essential elements and compounds required for life,from the environment to the organism and back to the environment.e.g., carbon cycle

5. What are the functions of lithosphere?

It is a home for human beings and wild lives.

It is a store house minerals and organic matters

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6. Mention the various types of public participation.

Pressure group

Watch dog Advisory council

Enforcing the environmental laws7. Explain biosphere?

The part of lithosphere, hydrosphere and atmosphere in which living organisms live andinteract with one another is called biosphere

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UNIT 2: ENVIRONMENTAL POLLUTION

ENVIRONMENTAL POLLUTION-DEFINITION:-

Any undesirable change in the physical, chemical or biological characteristics of anycomponent of the environment (air, water, soil) which can cause harmful effects on variousforms of life or property.

Types of environmental

pollution:- a) Air pollution

b) Water pollution

c) Soil pollution

d) Marine pollution

e) Noise pollution

f) Thermal

pollution g) Nuclear

hazards

a)AIR POLLUTION:

It is an atmospheric. condition where certain substances are present in conc. whichcan cause undesirable effects on man and his environment.

Ex. Gases, particulate matter, radioactive substances etc.

Gaseous pollutants sulphur oxides, nitrogen oxides, carbon oxides, volatile organic compounds

Particulate pollutants smoke, dust, soot, fumes, aerosol, liquid droplets, pollen grains

Radio active pollutants Radon 222, Iodine 131, Sr 90

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Sources of air pollution

Natural sources man made sources(anthropogenic)

1. Volcanic eruption thermal power plants (fly ash, SO2)2. Forest fires industrial units3. Biological decay vehicle emission-

(CO-77%, HC-14%, NOX-8%)-

(Heavy duty diesel vehicles- more NOX andSPM

Petrol vehicles CO & HC)

4. Sea salt spray fossil fuel burning5. Pollen grains of flowers Agricultural activities

Metallurgical plants (SO2, CO2)

Fertilizer plants

Textile mills

Refineries

Paper and pulp mills

Classification of air pollutants:

Air pollutants

According to origin According to state of matter

Primary pollutants secondary pollutants

(SO2, NOX, smoke) (PAN, SO3, aldehydes)

Gaseous air particulate air

pollutants pollutants(CO2, NOX) (dust, mist)

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Indoor airpollution:

Radon is an important air pollutant. It can be emitted from building materials like bricks,concrete, tiles etc. which are derived from soil containing radium. Burning of fuel produce

pollutants like CO, SO2

, soot and many other like formaldehyde, benzo(a)pyrene (BAP)are toxic and harmful for health. BAP is also found in cigarette smoke and is considered tocause cancer. A person using wood as fuel for cooking inhalesBAP equivalent to 20 packets of cigarette a day.

Effects of air pollution:

Effects on human:

Human respiratory system has a number of mechanisms for protection from airpollution. Bigger particles (> 10 micro m) can be trapped by the hairs and sticky muscuslining in the nose.

S. No. Pollutant Sources Effects on human

1 Aldehydes Thermaldecomposition of fats

and oils

Irritates nasal and respiratory tracts

2 Ammonia Chemical processes,dye making,explosives and

fertilizers

Upper respiratory passage

3 Arsenic Coal and oil furnaces Damages kidney, cause jaundice,lung and skin cancer

4 Carbon Monoxide Motor exhausts, oil

and coal furnaces

damages lungs and heart

5 Cadmium oil and coal furnaces Damages kidney

6 Chlorine Chemical industries Attacks respiratory tracks, mucousmembranes

7 Hydrocarbons Unburnt gasolinevapours

Fog formed with combination ofNOx affects respiratory system

8 Hydrogen Sulfide Sewage treatment,refineries

Irritates eyes, causes nausea, badodour

9 Nitrogen oxides Motor vehicleexhaust

Bronchitis

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10 Ozone Photochemicalreactions

Eye irritation, aggressive asthma

11 Sulphur dioxide Coal and oilcombustion

Obstructs breathing, irritates eyes

12 Suspended solids Industrialmanufactures

Eye irritation, asthma, air suffocation, lung cancer

Control of air pollution:

1. Using non conventional energy2. Using bio filters3. Planting more trees4. Reducing vehicle exhausts

5. Using less polluting fuels6. Using mass transport

7. Removal of particulate matter using electrostatic precipitator, cyclone filter etc.8. Setting of industries of EIA

9. Removal of NOX from vehicle exhaust

b)WATER POLLUTION:

Presence of foreign impurities (organic, inorganic, biological) in such quantities so asto constitute a health hazard by lowering the water quality and making it unfit for use.

Causes:

Point source Ex: flow of water pollutants from sewerage system, industrial effluent etc.

Non-point source Ex: agricultural land (pesticides, fertilizers, mining, construction

sites)

Classification of water pollutants:

1. suspended matter2. thermal discharge3. pathogens (bacteria, fungi, protozoa fungi)

4. natural organic pollutants5. synthetic organic pollutants6. inorganic chemicals

7. radioactive waste, oil, sediments

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Effects of water pollution

1. Objectionable colour and odour is unacceptable and unsuitable for drinking and otherpurposes.

2. highly turbid and very hard water is unpleasant to drink, food processing

3. acid and alkaline water cause serious health problem4. water borne infectious enteric disease like typhoid, cholera, dysentery, are the

predominant health hazard arising from drinking contaminated water5. radioactive pollution enter human body through food and get accumulated in thyroid

gland, liver, bones and muscles6. biodegradable waster deplete D O in the receiving stream, affect the flora cause creates

anaerobic conditions7. non biodegradable waste and pesticides travel the food chain and ultimately reach human

where they accumulate in fatty t issues8. thermal discharge in stream depletes D O

9. phosphate, nitrate, promote the growth of algae and encourage eutrophication10. Industrial effluents result in addition of poisonous chemicals such as arsenic, mercury,

lead may reach human body through contaminated food.

Control measures of water pollution

1. lay down standard fora. drinking waterb. disposal of waste water into water course/sewer/land

2. monitoring3. treatment

a. domestic treatment

screening sedimentation

filtration, pH adjustment

disinfectionb. waste water treatment

preliminary treatment

primary treatment

secondary treatment

advanced treatment

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C) SOIL POLLUTION:-

The contamination of soil by human and natural activities which may cause harmfuleffects on living beings.

Causes:-

Effects:-

Industrial waste Urban waste

Agricultural practices Radioactive pollutants

Biological agent

Affect human health Affect soil fertility

Reduce soil productivity

Cause abnormalitiesControl measures:-

Properly collect solid waste Microbial degradation

Recovery of products from waste For methane generation, use cattle dung

For biogas generation, use biodegradable organic waste

d) MARINE POLLUTION:-

The discharge of waste substances into the sea resulting in harm to living resources,hazards to human health, hindrance to fishery and impairment of quality for use of sea water.

Causes:-

Rivers

Catchment area Oil drilling and shipment.

Sources:

waste disposal

oil spill thermal pollution (plants located nearby coastal areas)

ship breaking activities aquaculture practices

nuclear test conducted in seas and oceansEffects:

disturb entire aquatic or marine ecosystem

oil has suffocation effect on most aquatic animals

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smaller animals can be caught in oil envelope and die thermal

Pollution may increase the temp. of water and DO may be depleted which causesdanger.

There may be chances for bioaccumulation and bio magnification in the food

chain due to the disposal of non-degradable wastes Oil promotes anaerobic conditions by preventing diffusion of oxygen from air Disposal of radio active wastes cause chronic, acute and genetic damage

Affects the recreational activity along the beaches Affect sensitive flora and fauna

Loss of buoyancy Affect phytoplankton, zooplankton, algal species, coral reefs, fish, birds and

mammals.Control measures:-

Ban to dump the toxic, hazards waste and sewage sludge.

Prevent sewer overflows Minimize coastal developmental activities Oil ballast should not be dumped into sea.

e) NOISE POLLUTION:-

Sound is mechanical energy from a vibrating source

Unpleasant and unwanted sound is callednoise

Sound can propagate through air, liquid orsolid

Sound is pressure perturbation in the medium through which it travels. Sound pressurecreates alternate compression and rarefaction. The number of c and r per unit time is calledfrequency.

Sound pressure does not produce linear impact on human. A logarithmic scale has beendevised. Noise is measure in terms of SPL which is a log ratio of sound P to a std. P.

It has a dimensionless unit decibel(dB). The international reference P is 2X10 power -5 Pa. Sound can affect ears either byloudness or by pitch (frequency). The CPCB has recommended the

permissible noise levels for various places.


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Area Permissiblenoise level(dB)

Day Night

Industrial 75 70

Commercial 65 55

Residential 55 45

Silent Zone 50 40

Sounds and their decibel scale:

1. Rocket engine 180 dB

2. Jet plane take off 150 dB3. Threshold of pain 140 dB4. Recorded music (max) 130 dB5. Construction works, news paper press 100 dB6. Motor cycle 90 dB7. Ordinary conservation 70/80 dB

8. Air condit ioning unit/ Light traffic 60 dB9. Normal living room 50 dB

10. Library or soft whisper 30 B11. Threshold of hearing 0 dB

Sources of noise pollution:

1. Industrial units2. Transportation modes

3. Construction activities4. Celebrations

5. Electric home appliancesNanjing 105 dB

Rome 90 dB

Calcutta 85 dB

Mumbai 82 dBDelhi 80 dB

Effects of noise pollution:

Interferes communication

Hearing damage (90 dB) Physiological and Psychological disorders

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Noise pollution duringDiwali:

The environmental (protection) (2nd

amendment) Rule 1999 has given the permissible limitof noise level produced from fire crackers to be 125 dB. According to recent test reports onfire crackers by National Physical Laboratory, the fire crackers available in the market producenoise beyond the permissible limit.

Atom bomb 135-138 dB

Hydrogen bomb

The Union Government and all the state governments shall follow the guidelines ofamendment89 of env. (Protection) Rule 1986 framed under Env. (Protection) Act 1986 whichsays

1. The manufacture, sale or use of fire crackers generating noise level exceeding125dBshall be prohibited.

2. For joined fire crackers the limit is taken as 5log 10 (N) dB; where N= no. ofcrackers joined together

3. The use of fire crackers shall not be permitted except between 6.00a.m and 10p.m.4. No crackers burning is permitted in/near silent zone areas near hospitals, educational

institutions, courts, religious places, etc.5. The State Education Resource Centre shall take appropriate steps to educate students

about the ill effects of air and noise pollution.

Control of noise pollution:

Reduction in source of noise]

Noise making machines should be kept in containers with sound absorbing media

Proper oiling will reduce noise from machinery

Using silencers fibrous material

Planting trees

Legislation can prevent excess sound production, unnecessary horn blowing etc.

f) THERMAL POLLUTION:-

Addition of excess undesirable heat towater

Causes:-

Nuclear power plant Domestic sewage

Hydro electric powerEffects:-

Reduction inn dissolved oxygen

Increase in toxicity


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Direct mortalityControl measures:-

The following methods should be adopted to control thermal pollution

Cooling towers Cooling ponds

Spray ponds

g) NUCLEAR HAZARDS:- OR RADIO ACTIVE POLLUTION

The physical pollution of air, water and soil by radio

materials. Causes:-

I) Natural causes:

Solar rays Radio nuclides in earths crust Environmental radiation

II)Anthrogeneic causes:-

Medical X-rays Radio isotopes

Nuclear test Nuclear installations

Nuclear reactorEffects:-

Causes skin burns, loss of teeth, vomiting anemia

Blood cancer Brain damage

Control measures:-

Radiation exposure protection

Radiation contamination protection Controlled area

Disposal of radioactive waste

SOLID WASTE MANAGEMENT:-

Any material that is thrown away or discarded as unwanted is considered as solid

waste. Types:-

Garbage or food waste Rubbish

Agricultural waste

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Cause:-

Effects:-

Industrial waste Hazardous waste

Over population

Affluence Technology

Health hazard Environmental impact

Control measures:-

Solid waste management include the waste generation

Solid waste generation

Collection of waste

Transportation

Storage

Segregation of waste

Disposal methods

Land fills Incineration Composting

Collection of solid waste

Disposal of solid waste

Land fill- Disposal of municipal waste in the upper layers of the earths mantle.

Incineration- Burn highly combustible wastes at very high temperature,

Composting or Bio degradation- Decompose the organic components of the municipal solidwastes.

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Waste utilizationo Reuseo Recyclingo Reclamation

Role of an individual in prevention ofpollution;-

Use stairs instead of elevators

Use public transportation walk or ride a bicycle Plant trees around building

Turn off lights, television sets and computer when not in use. Pay immediate attention to leaks in pipes.

Install waste saving equipments. Recycle glass metal and paper.

Compost garden waste Segregate waste and recycle

Buy locally made long losing material Buy environmentally degradable products.

Take some bag from home to market to purchase.

POLLUTION CASDE STUDIES:-

1. Bhopal gas tragedy:- (Air Pollution)

Pesticide factory-Union Carbide- corporation leak large volume of methyl isocyanate atmosphere Bhopal- India-midnight on December 3,1984-city-change- gas chamber-within a week 10,000 people died 1000 people turnedblind-lakhs of people still continue to suffer various diseases

2. Gulf War: (Marine Pollution)Gulf war was fought between Iraq and US-Period of 6 weeks in 1991-American

fighters dropped a lakh of bombs-force the Iraq army to withdraw fromKuwait- retreat of Iraq-burning of 700 oil wells-near sea shore oil from wellspills out into the sea-the floating oil oversea water nearly 80 km long-burning

of oil wells nearly 10 months-released huge amounts of pollutants likeCO2 andSO2 into the atmosphere-1 million birds killed.

3. Chernobyl Disaster : ( Nuclear pollution)Occur at Chernobyl in USSR 28 th April,1986-the reactor exploded- result ofuncontrolled nuclear reactions-radioactive fuel spread out in to the surroundingareas killed at least 20,000 people-damage to soil, water and vegetationaround60 km.

4. Minamata Disease :( Marine Pollution)Minamata- Small hostel village in Japan Chicago-chemical company produces

Venyl polymer plastics-industry release its effluent into Minamata sea-


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Effluents

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containing mercury ions-converted into methyl mercury- highly toxicconsumed by fishes affect human being through food chain-damagecentral nervous system-loss of vision and hearing-loss of muscularcoordination and severe headache- nervous disorders

DISASTER MANAGEMENT;FLOOD:

Submergence of waste areas of land under water for many days incontinuation

Causes: 1.Heavy rainfall

2. Sudden Snow melt

3. Clearing of forest foragriculture

4, Industries increase the value and rate of water discharge after astorm

Effects:

1. Damage to building and property2. Soil erosion is the major loss of agriculture3. Any product submerged by flood water cannot be rescued

Control measures:

1. Building wall prevent spilling out the flood water over flood pains

2. advance meteorological information will prevent flood damage3. reduction of run off by increasing infiltration through appropriate forestation

eg.flood in Bangladesh 1974

EARTHQUAKE:

Earthquake is the motion of the ground surface caused by wave motionstarting from a focal point

Causes:

1. Underground nuclear testing2. Volcanic eruption

3. Pressure of manmade dams, reservoir and lakes4. movements of plates of earth

Effects:

1. Cause Tsunami2. Deformation of ground surface

3. In hilly and mountain areas may cause land slides which damage thesettlement and transport system

4. Depending on the severity of the quake collapses house and people died in1000 eg. Earthquake in Bhuj town


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Control measures:

1. Government can inform the earthquake prone zone and caution residence2. building should be designed to withstand tremors

CYCLONE:

Cyclone is meteorological phenomena intense depressions forming over theopen oceans and moving towards the land

Effects:

1. Depends on the intensity of the cyclone2. Damage to human life crops roads, transport, communication could be very heavy

Control measures:

1. planting more trees on hostel areas2. construction of dams3. Radar system is used to detect cyclone eg.Cyclone in AP

LANDSLIDES;

The movement of eart materials like coherent rock, mud, soil and debris fromhigher region to lower due to gravitational pull is called landslide

Causes:

1. Earthquake, shock, vibration2. Deep water ground mining

3. movement of heavy vehicles on the unstable sleepy regionEffects:

1. Increase erosion of soil2. block the roads3. damage the houses, crop yield, life stock

Control measures:

1. Planting of deep rooted vegetation2. Encouragement for construction of bridges water ways3. Create national parks, sanctuaries biosphere.e.g.land slides in U.P

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Review questions

1. Give any three methods of air pollution control equipment Catalytic converters

Cyclone collectors

Electrostatic precipitators2. What is smog?

It is a mixture of smoke and fog which forms droplets that remain suspended in theair.

3. What is point source of water pollution?Point source is discharge pollutants at specific locations through pipes, ditchesinto

bodies of surfacewaters.

4. When a sound causes noise pollution?

Noise beyond 120 dB

5. What are the types of solid waste?

Municipal waste Industrial waste

Hazardous wasteWhat is waste minimization?

Industrial manufacturing system the primary concern should be reducing the quantities

of waste materials produced. This avoids the necessity to threat and disposal offsuch materials.

6. Name the chemical constituent of gas that caused death in Bhopal gas tragedy inIndia.

Methyl iso cynaide.

7. Define the term Tsunami.It is a large wave that are generated in a water body where the sea floor deformed byseismic activity. This activity displaces the overlying water in the ocean


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UNIT 3:NATURAL RESOURCES

Any component of the env. Which has intrinsic value of its own is called as resource.Any component which can be transferred in a way such that it becomes more valuable anduseful is termed as resource.

Resources

Renewable

Eg. Clean air, cleanwater

Non renewable

Ground water,minerals

Continuous

Solar energy, windenergy

Extrinsic

Human skills

Considered to berenewable with

considerable life

span-as long as theyhave the capacity torenew unless theyare affected bycatastrophes oranthrophogenicactivity.

Available only infinite quantity

their rate of renewal

is so slow that theyare considered asnon-renewable

Considered to beavailable always.

FOREST RESOURCES:

Forests are one of the most important resources of the world. Apart from having highcommercial importance they provide high environmental services also. They act as a blanketon the surface of the earth.

Around 1/3rd

of world land area was found to be forests. 1/5th

of world forests werefound in Brazil and 6-7% was in Canada and USA. But the matter under high concern isthe declination of forest cover year by year.

USES OF FOREST:

Commercial uses: Forests provide timber, fire wood, food material, resin, gum, non edible

oils, drugs, medicine, rubber, fibers, bamboo and many other important items.Ecological uses:

1. Production of Oxygen: Photosynthesis earths lungs2. Reducing global warming sink for carbon di oxide3. Wild life habitat 7 million species in tropical forests alone

4. Regulation of hydrological cycle prevent surface run off giant sponges 50-80%moisture

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5. Soil conservation hold solid particles tightly and prevent soil erosion wind breaks6. Pollution moderators: absorb toxic gases and purify air reduce noise pollution

OVER EXPLOITATION OF FORESTS:

Human beings depend heavily on forests for food, shelter, wood, fuel and medicinewith growing civilization etc. shooted up resulting in large scale mining, roadbuilding and clearing of forests.

Excessive use of charcoal, fuel wood, expansion of urban, agricultural and industrialareas and overgrazing have lead to over exploitation and rapid degradation of forests.

DEFORESTATION:

The total forest area of the world in 1900 was 7000 million hectares -1975 2900 mha 2000 2300 mha.

Deforestation rate intemperate countries are relatively moderate. But it is alarming intropical countries. It is estimated that in next 60 years we would lose more than 90% ofour tropical forest.

INDIAN STATUS:

Stabilized since 1982, with about 0.04% declaration per year between 1982 - 90.During this period it is estimated that about 1.44 mha land was brought underafforestation. As per our NFP, we have a target of achieving 33% forest area. But westill have only 19.27% of our land area covered by forests(satellite data).

MAJOR CAUSES OF DEFORESTATION:

1. Shifting of Cultivation 300 million people 5 lakh hectares of forest for slash andburn culture

2. fuel requirement

3. raw materials for industrial use4. developmental projects

5. growing food needs6. overgrazing

CONSEQUENCES OF DEFORESTATION

1. threatens many wild life species due to destruction of natural habitat

2. biodiversity is lost along with that genetic diversity3. hilly regions are made prone to landslides4. soil erosion and loss of soil fertility5. hydrological cycle is affected

(loss of rainfall, flood, drought etc)

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TIMBER EXTRACTION AND MINING:

The major activities in forest area are 1. timber extraction 2.mining

The important effects of timber extraction

are i) thinning of forestsii) loss of biodiversity, particularly tree breadingspecies iii) soil erosion and loss of soil fertilityiv) migration of tribal people from one place to another in search of newforest v)extinction of tribal people and their culture

MINING:

Mining is a process of removing ores from area which is very much below the ground level.Mining is done for the extraction of several minerals of metals like Fe, Mn, Au, Ag,etc.The minerals are especially found in thick forests.

Mining can be carried out in two ways

1. Surface mining2. underground mining or sub-surface mining

The effects of under ground mining on forest reserves is comparatively less than that ofsurfacemining

Relation between forest and climatechange:

Forests both influence and influenced by climate change. They play an important role in thecarbon cycle and the way we manage forests could significantly affect global warming.

Forests hold more than 50 per cent of the carbon that is stored in terrestrial vegetation andsoil organic matter. Hence, deforestation contributes significantly to net emissions of carbondioxide into the atm.

If the predicted global warming occurs, the impact on forests is likely to be regionallyvaried, dramatic, and long-lasting. Even now, we can see how any extreme weather has greatimpact on forests. For example, the 1999 storms in Europe caused heavy damage to forestsand also to trees outside forest areas.

The Kyoto Protocol on climate change may have a great impact on forest management.Under the Protocol, a country with forests earns emission credits, since its forests absorbcarbon dioxide. These credits are tradable,

that is, a developing country can sell its credits to an industrialized country that hasexceeded its quota of emissions. The latter would invest inafforestation and reforestation projects in the developing country.


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DAMS BENEFITS AND PROBLEMS

River valley projects with big dams are considered to play a key role in the development ofa country. India has large number of river valley projects

1. These dams are regarded as symbol of national development.

2. provides large scale employment of tribal people and increase the std. of living ofthem

3. contribute for economic uplift and growth4. help in checking flood5. generate electricity6. reduce power and water shortage7. provide irrigation water

8. provide drinking water to remote areas9. promote navigation and fishery.

Environmental problems:

The environmental problems can be at upstream as well as downstream

Level

Upstream problems

1. Displacement of tribal people2. Loss of flora and fauna3. siltation and sedimentation near reservoir4. stagnation and water logging near reservoir

5. growth of aquatic weeds6. micro climatic changes7. RIS causes earthquakes8. breeding of disease vectors

Downstream problems

1. Water logging and salinity due to over irrigation2. micro climatic changes3. salt water intrusion at river mouth4. loss of fertility due to sediment deposits

5. out break of vector born diseases.

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WATER RESOURCES

Water is an indispensible resource. Around 97% of world surface is covered with water.Most of the animals and plants have 60-65% of water in their body.

Unique features of water

1. High specific heat2. High latent heat of vapourisation

3. Good solvent for oxygen, nutrients and pollutants4. Anomalous expansion on freezing

5. High surface tensionGlobal distribution of water is very much random depending on the geographical conditions.

The availability of water decreases in the following order.

1. Tropical rain forest2. Temperate regions

3. DesertsWater is used for domestic, irrigation and also industrial purposes

Out of the total available water 75% is used for agriculture, 20% for industrial usage. In ourcountry ~93% of water is used for agricultural purposes.

Ground water:

9.86% of fresh water is ground water and it is 35-50% greater than surface water.

Aquifer: The layer of soil which is permeable has the ability to store water is called an aquifer.It is generally made up of gravel, sand etc.

Unconfined aquifer: it is covered by permeable layer. The recharge of this layer is by rainfallor snowmelt.

Confined aquifer: sandwiched between impermeable layers. The recharge is throughunconfined aquifer layers.

Over utilization of ground water:

Over utilization of water leads to rapid depletion of water resources, groundsubsidence, lowering of water table and water logging.

Effects of over utilization of ground water:

Reasons: Economic development, rapid industrial growth and population explosion

The use of ground water and surface water rates which are higher than that ofrecharge ultimately leads to

Water scarcity Water logging

Salination alkalization

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water pollution or contamination

creates declining of water levels crops failure and reduction in agricultural production

over pumping of ground water create drought, famine and foodshortage over pumping of ground water sea water intrusion in coastalaquifers

land subsidence may due to over pumping of ground water river pollution due to industrial activities and dumping of waste into rivers, which in

turn force to utilize the ground water, ultimately leads to overpumping

Clean water is universal right. It is the responsibility of everyone to ensure the purity of

water. Water is a valuable commodity and it has to be

conserved. Surface water:

When evaporation and transpiration rates are lower than the rainfall, surface water bodylike lake, river, pond, streams etc. are formed.

Flood: over flow of water, whenever the water in flow is greater than the carryingcapacity of the channels flood occurs.

Causes:

1. heavy rainfall, snow melt, sudden release of water from dams.2. Prolonged down pour leading to overflowing of rivers and lakes3. Reduction in carrying capacity due to obstructions or sediments etc.4. Deforestation, overgrazing, mining increases water run off

5. Removal of dense forests from hilly regionsEffects:

1. Submerges the flooded area2. Loss of soil fertility due to soil erosion3. Extinction of civilization at costal area

Flood management:

1. Dams and reservoirs can be constructed2. Embankments and proper channel management

3. Flood way should not be encroached4. Forecasting or flood warning

5. Decrease of run off by infiltration through afforestation or rain water harvesting etc.

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Drought :

Unpredictable delay in climatic condition occurring due to monsoon rain failure.

Types:

Meterological : in order of month or year, actual moisture supply at a given placeconsistently falls below critical level.

Hydrological: deficiency in surface and subsurface water supplies

Agricultural: inadequate soil moisture to meet the need of a particular crop at particular time

or susceptibility of crops during different stages in its development

Socioeconomic: reduction in the availability of food and social securing of people

Causes:

Deforestation and lesser rainfalls coupled with cutting of trees for timber leadsto desertifictation.

Over drafting of ground water, subsidence of soil, drying of wetlands

Pollution of soil with solid waste, industrial effluents etc makes land useless and dry

Population explosion in man and livestock leads to enhanced requirement of timber,fuel wood, grazing

Shifting cultivation

Effects:

Increase of water in stream pond

Ground water table get declined

Loss of agricultural crops

Loss of biodiversity

Government spent a lot of money as drought relief f und

Control measures

Rain water harvesting

Watershed management

Prevent deforestation

Encourage afforestation

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CONFLICTS OVER WATER

Due to increase in population and decrease in water resources conflicts over water starts

Conflicts over the water around world was classified as

Control of water resources

Military food resources

Political resources

Terrorism

Military targets

Development disputes

Causes:

Conflicts through use 1. Shipping traffic in international water .2 dam construction

Construction of power stations on

Conflicts through pollution-rhine river,Europe

Distributional conflict-relative storage

Euphrates, Nile, Ganges - plataneous in upper basin, reduced in lower basin due toextensive use.

Anatolian dam project by turkey Farakka dam in India

Distributional conflict: Absolute shortage. Colorada and Rio Grande, Jordan

Conflicts management:

Enact laws to check practices to control water pollution

Sharing river solved by interlinking river

Power must be given to national water authority and river basinauthority and river s-basin authority for equitable distribution of

basin water- demand fo0r nationalization of water needs

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WORLD FOOD PROBLEMS:

Problems mainly under nutrition and malnutrition

Natural calamities:-famine, drought, earthquake, flood, gale, storm Disease and medical facilities

Pest damage:-insects, bacteria, viruses, parasites consume 60% of world

s foodproduction

Hunger Population explosion in rural areas

Environmental pollution Lack of water for irrigation

Less rainfall due to deforestation Livestock overgrazing

Overfishing

CHANGES CAUSED BY OVERGRAZING AND AGRICULTURE:

Overgrazing:

Process of eating away the vegetation along with its roots without giving a chance to regenerate

Land degradation-leads to organically poor, dry, compacted soil cannot be usedfor further cultivation

Soil erosion-cover of vegetation gets removed from soil Loss of useful species-good quality grasses and herbs with high nutritive value, when

grazed lose even the root stocks which carry the reserve food for regenerationget destroyed which gives raise to secondary species like parthenium, Lantane,

Xanthium etc To prevent match the forage supplement to the herds requirement.eg.Switch grass

Modern agriculture:

The practice through which specific plant species are cared and managed so as to obtainmaximum yield of consumable parts of plants agriculture

Makes use of hybrid seeds and selected and single crop variety, high tech equipmentand lots of energy subsides in the form of fertilizers, pesticides and irrigation water e.g.green revolution

Damage to soil

Water contamination Water scarcity

Global climate change Water logging-results when soil is over irrigated

Soil salinity-increase plant productivity, interferes with water uptake by plants Fossil fuels and pesticides produce air pollution

Impacts related to high yielding varieties:

Monoculture ie the same genotype is grown over vast areas. Disease spread easily Micronutrient imbalance e.g Zinc deficiency-affect soil productivity

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Nitrate pollution-nitrogenous fertilizers applied deep soil contaminates ground water.cause blue baby syndrome methaemoglobinemia- affects infants

Eutrophication: Over nourishment of lakes due to agriculture field wash out -leads toalgal bloom-dead organic matters increases due to decomposition-leads to oxygendemand

Problems associated with pesticideuse:

Evolution of genetic resistance

Imbalance in ecosystem Creation of new pest

Persistence, Bioaccumulation and Biomagnification Mobility through soil, water, air, washed away into rivers, streams, when it rains can

harm fishes Creating super pest

Death of non starget organisms

Salinity Water logging

Water logging / salinisation:

Saturation of soil with irrigation water or excessive precipitation. So that water table risesclose to surface.

Water logging results when soils are over irrigated without drainage. Occurs in clayey soil,soil root zone becomes saturated with so much water blocking oxygen supply for growth andsoil becomes unsuitable. Carbondioxide and ethylene accumulate around roots and affects

plants

ENERGY RESOURCES

Growing energy needs:

Population explosion, Luxurious life, Industries, Agriculture, mining, transportation,lighting, cooling, heating, building all need energy. Fossil fuels like coal, oil, natural gasproduce 95% of energy

Sources of energy

Primary-Renewable energy-resources which can be generated continuously in natureand are in exhaustible and can be used again endlessly.wood, Tidal, Solar,wind, hydropower, biomass, biofuel, geothermal, hydrogen

Non renewable energy- Resources which have accumulated in nature over along span of time and cannot be quickly replenished whenexhausted.coal, petroleum, natural gas

Secondary-petrol, electrical energy, coal burning


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Energyrenewable

Advantage Disadvantage

1. Wide availability2. Low cost3. Decentralized power

production4. Low pollution5. Available for the

future

1. Unreliable supply2. Produced in small

quantity3. Difficult to store4. Cost more

Energy non

renewable

1. Available in high

concentrated form2. Easy to store3. Reliable supply4. Lower cost

1.highly pollution

Available only in few placesHigh running costLimited supply and will oneday get exhausted

Use of alternate energy sources:

Refers to energy sources which are not based on the burning of fossil fuels or the splittingof atoms.

Solar energy:

Total energy from sun per year-35,000 times the energy used by man

Used to run car, power plants and spaceships

Energy harvestingdevises: Solar heat

collectors

Solar cells

Solar cooker

Solar water heater

Solar furnace

Solar power plants

Wind energy:

Average wind velocity of earth -9 m/sec and power produced when a windmill is facing thewind od 10 miles/hr-50 watts.eg.largest wind farm-Kanyakumari in tamilnadu is generating380MW electricity


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Hydro power:

Comes from damming of rivers and utilization of high pressure, its kinetic energy istransformed into turbine blades and used to generate electricity

Minimum water falls height-10 m

Hydro power potential of India-4x1011

KW/Hr

Tidal Energy

Uses the natural motion of tides to fill reservoirs which are then slowly discharged throughelectricity producing turbines

Ocean thermal energy

Energy available due to the difference in water temperature. The surface of the tropical

ocean and at deeper level is called OTE. A difference of 200c or more is required for

operating OTE power plants.

Geothermal energy

Energy harassed from the hot rocks inside earth. eg. natural geysers inManikaran,kully,sohana

Biomass energy

Organic matter produced byplants

Types:

1.Energyplantations:

Solar energy is trapped by green plants through photosynthesis and converted to biomass e.gLeucaema,Sugarcane, sweet sorghum, Sweetbeet aquatic weeds like hyacinth, Seaweeds,potato,cereal-energy plantations

Produce energy by burning directly or by getting converted into burnable gas or converted tofuels by fermentation.

Petro crops

Latex containing plants Euphorbias, oil palms rich in hydrocarbons and yield oil likesubstance under high temperature and pressure-refined to form gasoline

LAND RESOURCE

Land is critically important national resource which supports all living organisms includingplants and animals. The soil profile of land determines its ability to serve socio-economicneeds.

It has been estimated that more than 5000 million tonnees of top soil is erodedannually along with 5 million tones of nutrients. About 1/3 of this is lost in sea

while the rest in reservoirs and rivers leading to flood.


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3. Alley Cropping or Agro forestry: In this method crops are planted together in stripsor alleys between trees and shrubs that can provide fruits and fuel wood. The treesand shrubs provide shade which reduce water loss by evaporation and preserve soilmoisture.

Wind Breaks or Shelter Belts: Wind breaks and shelter belts or trees are established to reduce

wind erosion and also for retaining soil moisture.

ROLE OF INDIVIDUAL IN CONSERVATION OF NATURAL RESOURCES:

Natural resources-forest,water,soil,food,mineral and energy

Overuse of these resources cause problems

Conserve water:

Dont keep water taps running Install water saving toilets

Check forwater leaks Reuse soapy water

Use drip and sprinkling irrigation Conserveenergy

Turn off lights,fan when not in use Use solarcooker for cooking

Try riding bicycleProtect soil:

Dont uproot plants

Grow grass which binds soil andprevent erosion

Make compost Use green manure Dont over irrigate

Use mixed croppingEQUITABLE USEOF RESOURCES FOR SUSTAINABLE IFE STYLE:

Most developed countries like USA, Canada, Japan, Australia have 22% ofnatural resources, use 88%.73%of its energy and command 85%of its income

Less developed countries has 78% of population, 12% Usage of natural resources, 27%of energy, 15% of income

Gap arises due to increase in population distribution of resources and wealth

Problem solved by equitable distribution of resources and wealth Global consensus has to be reached for more balanced distribution of basic resourceslike safe drinking water, food, fuel etc. So poor low developed countries able to sustaintheir life

Two basic cause of unsustainability are over population in poor countries and overconsumption of resources by rich countries generate wastes

Rich countries lower down their consumption level

Poor countries fulfilled by providing them resources

Review questions

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1. What is artesian well?

A well or hole in aquifer flows freely at the surface

2. What is wetland?give examples and use

Wetlands are the natural water storage bodies on ground surface

Eg.Swamps, Meadows, Marshes

3. State the major process which have major environmental impact while processing of minerals.

Smelting,chemical extractions

4. What is salinization?

During over irrigation, all the water is not absorbed in the soil. such water evaporatesleaving behind a thin crust of dissolved salts in the top soil.

5. Give two examples of primary and secondary sources of

energy? Primary source-fossil fuels, hydro energy

Secondary source-petrol, electrical energy

6. What is ocean thermal energy conversation?

In oceans, a thermal gradient (i.e., the temperature difference) of about 200C existsbetween surface water heated by sun and colder deep water. This difference can be harnessedto produce power. This concept is OTEC.

7. Give any four environmental benefits of dam

Source of cleaner and safer power

For irrigation of agricultural lands

Helps in recharging of ground water

Habitat for many fishes and wildlife

8. What are the sources of water

Ground water, surface water, sea water, rain water

9. What is sardar sarovar Narmada project?

It is a multipurpose project on river Narmada, bringing the benefits of irrigation,power and drinking water to Gujarat, Mathya Pradesh and Rajasthan.

10. What is integrated pest management?

The process of controlling crop pests using ecological system

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UNIT 4:SOCIAL ISSUES AND THE ENVIRONMENT

From unsustainable to sustainable development:

Brundland commission describes sustainable development as the development thatmeet needs of present generation without compromising ability of future generations to meet

their own need

Concept of sustainable development

A symbiotic relationship between consumer human race and producer natural system Compatibility between ecology and economics

Aim of sustainable development:

Inter generational equity Intra generational technology

Significance of sustainable development:

Developing appropriate technology

Reduce , reuse, recycle of natural resources Providing environmental education and awareness

Consumption of renewable resources Conservation of nonrenewable resources

Population controlUrban problems related to energy:

Urbanization:

Movement of human population from rural areas top urban areas for betterment ofeducation, communication, health, employment etc

Causes;

Cities are main centers of economic growth, trade, transportation, education, medicalfacilities and employment

Urban sprawl:

Urban growth is fast , so difficult to accommodate with their limited area .So cities spreadinto rural areas

Urban energy requirement: Residential and commercial lighting

Public and private transportation Electrical and electronic appliances

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Solution:

Use public transport instead of motor cycles

Energy consumption must be minimized

Use solar and wind energy

Impose strict laws, penalty, and energy audit

Water conservation:

Process of saving water for future utilization

Water source:

Fresh water

River

Stream Pond Ocean

Need for water conservation:

Population increases water requirement also increases Due to deforestation annual rainfall decreases

Over exploitation of ground waterWays of water conservation

Reducing evaporation loss Reducing irrigation loss

Reuse water Avoid sewage discharge

Water conservation method

Rain water harvesting Watershed management

Rain water harvesting

Objective:

To meet increasing demands of water

Raise water table by recharging ground water

Reduce ground water contamination from salt water intrusion

Roof top rainwater harvesting

Involves collecting water that falls on roof of house Rainwater from roof top, road surface, play ground diverted to surface tank

Advantages of rainwater harvesting

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- Decrease in soil erosion.- Restoration of ecological balance.

Resettlement and Rehabilitation of people:

Resettlement simple relocation or displacement of human

populat ion.Rehabilitation making, system to work again by allowing, system to functionnaturally. Includes replacing the lost economic assets, Safeguard Employment, Providesafe land for building

Repair damaged

infrastructure. Effects:

Loss of land Loss of recourse

Unsatisfactory comp[enasation Social and cultura problems

Changes in tradition of indigenous people Spread of disease

Submergence of valuable forest Waterlogging

Extinction of wild life

Environmental ethics:-

Over exploitation of forests, land, water as well as various living components

of biosphere and failure to tackle the problem of pollution and environmental degradationare exposing the humanly to the thread of a global environment crisis.

It emphasis that real development cannot occur unless the strategies which areformulated are implemented are environmentally sustainable. Even though ourgovernment is formulating several rules, regulations, policies, laws, it is the duty of eachand every one to protect our nature.

Therefore human beings are ethically responsible for the preservation of the worldsecological integrity. The environment ethics literally means conscious efforts to protectenvironment and to maintain its stability from the pollutants. Following are some of the

ways to safeguard environment.1. To sacrifice the consumption of some of the good which reduces environment quality2. Minimize the resource utilization and conservation3. Adopt sustainable and eco friendly development. (e.g) reduction of waste, recycling,

waste management and harvesting non conventional energyIf we change as individuals then the society will also change by itself. The societyis nothing but an extension of the individual.

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Green House Effect and Global Warming:

The raise of earths surface temperature due to intense green house effect is called globalwarming.

Causes:

Over the last century, the level of carbon dioxide in the atm. Has increase by 25%,the level of nitrous oxide by 19% and the level of methane by 100%. These 3 major globalwarming gases are released into the atm. by burning of fossil fuels,industrialization, mining, deforestation, exhaust from increasing automobiles and otheranthropogenic activities.

Effects:

1. Increase evaporation of surface water influence climate change2. Leads to declining biodiversity3. Melting of mountain glaciers and polar ice, which cause rise in sea level4. Change the climate and rainfall reduction in food production5. The biological productivity of ocean also decreased due to warming of earths surface6. With more carbon dioxide in the air, the plants will grow bigger with increase in yield

and resulting in the soils getting poor quality

7. If proper precautions are not taken, the conc. Of green house gases may double in theatom. with in next 50 years, and will makes the average global temp. to 45

0C.

Ozone layer depletion:

Ozone is an important chemical species present in the stratosphere. Its conc. is about

10 ppm. It acts as a protective shield for the life on the earth. Ozone is produced and alsobroken down by photochemical reactions, thus maintaining equilibrium.

Causes for ozone layer depletion:

1. Chlorine released from CFC and Bromine released from halogens are the mostimportant chemicals associated with ozone layer depletion

2. The halogens are used in fore extinguishers and CFC are extensively used inair conditioners and refrigerators.

3. Methyl bromide used during packaging of fruits to prevent bacterial action flows outinto the atmosphere as soon as the packing is opened. This cause heavy damage toozone.

4. High altitude aircrafts and chemicals emitted by industrial plants and automobiles.

Effects:

1. Marked rise in cause skin cancer2. Damage immune system

3. Eye ailment such as cataract4. Shorter life of paints and plastics

5. Restricted growth and crop damage

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6. Destruction of aquatic life

Waste land reclamation:

Any land which is not put to optimal use is defined as waste land. The waste landdo not fulfill their life sustain potential wasteland contributes about 20.17% of the

totalgeographical area of India.

Reasons for formation

Over grazing and over exploitation Toxic effluent discharged from sewage and industrial wastes

Mining activities destroy forest and cultivable land Use of pesticides also produce wasteland

Erosion, desertification, water logging also degrade land

Wastelands can be reclaimed by the following way

Conserving the soil land is brought under vegetal cover. This can bedone by growing grasses and shrubs

To reclaim the land/soil, effective participation of the people, voluntary agencies and government is very important

Consumerism and Waste Products

Consumerism refers to the consumption of resources by the people. Early humansocieties used to consume much less resources. But the consumerism has increased to a very

large extent. Consumerism is related to both population size and increase in demands due tochange in life style.

Population has increased tremendously. World Bank estimates our population to reach11 billion by 2045. Two types of conditions of population and consumerism exists.

1. People over population: When there are more people than available food, water andother resources in an area causes degradation of limited resources poverty and undernourishments. Low Developed Countries (LDC) are more prone to these conditions. There isless per capita consumption although the overall consumption is high.

2. Consumption over population: These conditions occur in more developed

countries (MDC). Population size is smaller but the resource consumption is high due toluxurious life style (i.e.) per capita consumption is high. More consumption of resourceslead to high waste generation greater is the degradation of the environment.

According to Paul Ehrlich and John Hodlrenmodel

Overall environmental impact = no. of people x per capita use of resources x waste generatedper unit of resources

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Parameter MDC LDC

No. of people low High

Per capita consumption ofresources

high Low

Waste generated high Low

Over all environmental impact of these two types of consumerism may be same oreven greater in case of MDC.

Comparison of consumption and waste generation

Parameter Global value %

USA India

Population 4.7 16

Production of goods 21 1

Energy use 25 3

Pollutants and wastes 25 3

CFC Production 22 0.7

Environment (Protection) Act, 1986

CG is to take action to protect and improve environment and SG to co ordinate actions. CGto set up

1. Std of quality of ]air, water or soil2. Maximum permissible limits of concentration of pollutants (including noise pollutant)3. procedures and safe guard for handling hazardous items4. Prohibition of using hazardous items

5. Prohibition and restriction of certain industries in certain area6. Procedure and safe guard for prevention of accidents

Environment (Protection) Rules, 1986

SPCB is to follow the guidelines provided in schedule VI. Some are as follows

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1. Advises industries for treating the waste water and gases use of technology achieve prescribed std.

2. Encourage recycling and reusing the wastes3. Encourage recovery of biogas, energy and reusable matter

4. Discharge of effluents and emissions into environment is permitted by SPCB after

taking into account capacity of the receiving water body5. To emphasize clean technology to increase fuel efficiency and decrease environmental

pollutantsThe act provides for environmental Audit for checking complying with the environmentallaws and regulations.

Air (Prevention & Control of Pollution) Act, 1981

Salient features

1. Prevention, control and abatement of air pollution2. Air pollution has been defined as the presence of any solid, liquid or gaseous substance

(including noise) in the atmosphere in such a concentration that may be or tend to beharmful to human being or any other living creature or plants or property orenvironment.

3. Noise pollution inserted in 19874. CPCB & SPCB similar to water pollution board5. Section 20 provides for emission std to auto mobile6. Section 19 provides for SG to declare air pollution control area in consultation with

SPCB7. Direction of PCB can be appealed in the appellate authority.

Water (prevention and control of pollution) Act 1974:

Maintaining and restoring the wholesomeness of water by preventing and controlling itspollution. The salient features and provisions of Act are summed as follows.

1. Maintenance and Restoration of Quality surface and ground water2. Establishment of central PCB and state PCB

3. Confers powers and functions to CPCB and SPCB4. The act provides for funds, budgets, accounts and audits of the CPCB & SPCB

5. The

63816326 environmental science and engineering lecture notes edited

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