Saturday 30 January 2021

Chapter 16 Environmental Issues

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 16- ENVIRONMENTAL ISSUES 

CHAPTER NO.16 ENVIRONMENTAL ISSUES

 

A183

 

INTRODUCTION

Pollution is defined as an undesirable change in physical, chemical or biological or Characteristics of air, water and land that may or will adversely affect human life, Industrial progress, and living conditions.

Word pollution has been derived from Latin Word “pollutionem” which means defilement.

Pollutant is a substance, chemical or factor that on release into the environment has an adverse effect on human interest.

 

TYPES OF POLLUTANTS:(On the basis of degradation)

1. Biodegradable pollutants capable of being removed or degraded by biological Actions e.g. domestic sewage, livestock wastes, municipal sewage etc.

 

2. Non-biodegradable: The substances which are normally not acted upon by microbes or acted upon very slowly. E.g. glass, plastic, DDT, pesticides,polyethylene bags, heavy metals etc. (On the basis of occurrence in nature)

 

Primary Pollutants: These are present in the same form in which these are added by man e.g. SPM, CO, DDT, Hydrocarbons, pesticides, fertilizers etc.

 

Secondary pollutants: These occur in different forms and are formed by

Reaction between primary pollutants in the presence of sunlight e.g. HNO3

H2SQO,, PAN etc.

(On the basis of existence in nature)

Quantitative pollutants: These are naturally present in nature and are also added by man. These become pollutants when their concentration reaches beyond a threshold value e.g.CO2, Nitrogen oxide etc.Qualitative pollutants: These are not present in nature but are added by due to hu- man activities e.g. pesticides, fungicides, herbicides.

 

TYPES OF POLLUTION:

On the basis of origin:

1. Natural Pollution: This type of pollution is caused by natural phenomenon like volcanic eruptions, dust storms, pollens etc.

 

2. Anthropogenic Pollution: This type of pollution is caused by man e.g. waste

of industries, farm runoff, power plants, etc.

On the basis of medium:On the basis of medium in which it occurs, pollution is of three types:Air Pollution, Water Pollution and Soil pollution.On the basis of physical nature:

Pollution is named after the physical nature of pollutant like;Gaseous Pollution, Dust Pollution, Therma! Pollution, and Noise Pollution.

 

LET’S KNOW WHAT WE HAVE LEARNT!

PART-A VERY SHORT ANSWER TYPE QUESTIONS:

A. MCQs:

 

1. Which of the following is not a pollutant?

(A)CO2

(B) CO

(C) NO2z

(D) SO2

 

2. Pollutants which are present in same form in which these are added by manare:

(A)Secondary pollutant

(B) Quantitative Pollutant

(C) Primary Pollutant

(D) Qualitative Pollutant

 

3. The pollutants which are naturally present in nature and are also added by man are:

(A) Secondary Pollutant

(B) Quantitative Pollutant

(C) Qualitative Pollutant

(D) Primary Pollutant

 

4. The pollutants which are not present in nature but are added by human activities are:

(A) Non-Biodegradable

(B) Qualitative Pollutant

(C)Secondary Pollutants

(D) Both A and B

 

 

5. Non-Biodegradable pollutants from the following are:

(A) NOz, CO2, SO2

(B) Sewage, livestock Waste

(C) DDT, pesticides, polythene bags

(D) All of these

 

B. TRUE/FALSE:

1. Secondary pollutants are formed by reaction between primary pollutants.

2. PAN is a secondary pollutant.

3. DDT is

biodegradable.

 

C. FILL IN BLANKS:

1. —-------- is a substance, chemical or factor that on release in environment has

an adverse effect on human health.

2. Word Pollution has been derived from Latin word ---—---.

 

A.MCQs:

 

(A)CO2

(C) Primary Pollutant

(B) Quantitative Pollutant

(D) Both A and B

(C) DDT, pesticides, polythene bags

 

B. TRUE/FALSE:

1. TRUE

2. TRUE

3. FALSE: DDT is non-biodegradable.

 

C.FILL IN BLANKS:

1. Pollutant

2. Pollutionem

 

SHORT ANSWER TYPE QUESTIONS:

1. What is pollution?

2. What is a pollutant?

3. Name some primary pollutants?

4. List the types of pollution on the basis of origin?

5. Expand the term SPM.

 

PART: C LONG ANSWER TYPE QUESTIONS:

1. What is pollution? Explain its types.

2. What is a pollutant? Explain its types with examples.

 

 

 

 

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INTRODUCTION

 

POLLUTION:Occurrence of foreign particles or gases in atmosphere which are harmful to man, vegetation, animals and buildings. Clean and pure air is essential survival and good health.

 

POLLUTANTS:A pollutant is substance or energy introduced in air that has undesired and

adverse effects over its quality and usefulness.

 

 

Pollutants are divided into several categories:

(a) Biodegradable (b) Non-biodegradable

 

(a) Primary pollutants (b) Secondary pollutants

 

(a) Quantitative pollutants (b) Qualitative pollutant

 

(a) Natural pollution (b) Anthropogenic pollution

 

(a) air pollution (b) water pollution (c) soil pollution

 

 

CAUSES OF AIR POLLUTION:

SOURCES OF AIR POLUTION:

 

1. INDUSTRIAL AIR POLLUTANTS

(i) Metallurgical processes: Release of dust and fumes loaded lead with nickel etc.

 

(ii) Chemical industry: Hydrochloric acid, chlorine gas, zinc, lead, arsenic

and many oxides CO,CO2,SOz pesticide, fungicide, weedicides and fertilizer industry releases lot of chemicals.

 

(iii) Thermal power plant: Release particulate matter and gaseous air pollutants.

 

2. MOBILE COMBUSTION SOURCES: Locomotives, Air crafts and automobiles.

[Arecord :- In Dehli Automobiles release CO (77.2%),NO (7.7%) tons are pumped out from automobiles only.]A record hitting data of metro cities show a considerable amount of lead let out from auto mobiles threatens lead poisoning among residents of cities.

 

3. BURNING OF FOSSIL FUEL: Coal - It produces COz, incomplete burning releases CO, variety of hydrocarbons, methane and soot.

 

4. AGRICULTURAL WASTE: CO, methane are produced from paddy, guts of Livestock, burning of biomass, crop spraying.

Dusting of pest and weed control emits organic phosphates,chlorinated hydrocarbons arsenic and lead into air.

 

5 IONIZING RADIATIONS: Alpha, beta particles and gamma rays produced during xperimentation nuclear explosion, and in nuclear power plants.

 

6. SUSPENDED PARTICULATE MATTER: Major air pollutant generated from coal (oil refineries ,power plants) cement dust,silica dust(stone crushing ,welding) and lot of dust is blown by transport vehicles.Fly ash and smoke from

burning coal .

 

7. SOLID WASTE DEPOSITION IN LANDFILLS: Generate methane.

 

8. NATURAL AIR POLLUTANTS: Pollen spores, marsh gas ,volcanic gases from natural phenomenon in nature.

 

MAJOR AIR POLLUTANTS

1. Oxides of Carbon:-(a) CO2 released by human activities such as burning fossil fuel as well as natural processes respiration and volcanic eruptions. It is a greenhouse gas, as it traps heat.

 

(b) Carbon monoxide: it accounts for 50% of total air pollution . 50% of CO is

emitted from automobiles.Over 15 million tonnes of CO is added to

environment

every year.Produced due to use of coal and oil for energyproduction,manufacturing and transport.respiration process. About 15% increase in last 100 yearsis recorded due to

Deforestation and burning of fuel, biomass, forests, savannah grass lands for

pasture and cropland.

 

3. Sulphur dioxide; and nitrogen dioxide: Acid rain is 60-70%due to SO2 and

30-40% due to NO2. Dry deposition formed from acidic gases and particles in wind.Wet deposition formed of acidic water received through rain, fog and snow.pH of rain fall estimated 4.0 to 6.5. Produced from ore smelting, coal burning, industrial

processes,municipal incineration.Sources of oxides of nitrogen ; petrol and diesel

vehicles,burning biomass,nitrogen fertilizers. Lichens are sensitive to SO2.

 

4 .Aerosols: These are chemicals present in the form of vapours or fine mist ;contain chlorofluorocarbons. CFC are emitted from jet planes,refrigerators, air conditioners etc.Burning of plastics releases poly chlorinated biphenyls (PCB)

 

5. Benzpyrene. :It is a carcinogen produced by tobacco smoke, industrial affluence and automobile exhausts.

 

6.Photochemical oxidants: Unburnt hydrocarbons react with nitrogen oxides to

form Os, peroxy-acyl nitrates (PAN), aldehydes. Some form peroxy - propional

nitrate (PPN), peroxy -buteryi nitrate.

 

7. SMOG: Formed by combination of smoke and fog. Term smog was coined by scientist Dr. Henry Antoine. It contains SO2, NO: etc.

It is of two types: —--- London smog (sulphurous smog), Photochemical smog

(Los Angeles smog).Photochemical smog is produced due to reaction between nitrogen oxides and unsaturated hydro carbons.

 

7. Hydrocarbons: Volatile organic carbons (VOCs) e.g. unsaturated ethylene, CH. Most of hydrocarbons are added by burning of petroleum and methane by decay of organic matter ,from paddy fields (about 40%). Methane is also a greenhouse gas.

 

8.Particulate matter:--It is of two types: —

(a) settable (more than10 um)

(b) Suspended

Suspended particulate matter is of three types: ——

 

(i) Aerosol (less than 1pm) (ii/Dust solid (more than 1 pm) (iii) Mist liquid (more

than 1 ym) Anthropogenic aerosols (made by human activity) account for about 10% of

our atomosphere.Due to pollution, average age of person decreasing by 3.2 years.[A report 2016] most polluted cities of India are: Ghaziabad, Noida, Delhi,Mumbai and Lucknow. Famous monuments are affected by air pollution.

 

Let us know What we have Learnt!!

1.MULTIPLE CHOICE QUESTIONS:

 

1.Who was first scientist to coin the term smog and describe layers of smog?

(a) Nikolas Tesla

(b) Stephen Hawking

(c) Dr. Henry Antoine

(d) Nicolas Copernicus

 

 

2. Which of following particles is called particulate pollutants?

(a) Ozone

(b)radon

(c)Fly Ash

(d) Ethylene

 

3. The major photochemical smog is:

(a) Hydrogen peroxide

(b) Chlorofluorocarbon

(c) per oxy acetyl nitrate

(d) all of above

 

4. Smoke ,fumes, ash, nitric acid, sulphur dioxide are the main sources of:

(a) Primary pollutant

(b) Secondary pollutant

(c) Biodegradable pollutant

(d) None of above

 

5. Carcinogen produced in tobacco smoke and auto mobile exhausts is:

(a) H2SOz,

(b) chloroflourocarbons

(c) Benzpyrene

(d) all of above

 

2. TRUE / FALSE:

1. Peroxy-acyl Nitrate and ozone are primary pollutants.

2. Wet deposition of acid rain is received through rain, fog and snow.

3. Indoor pollution is caused by tobacco smoking, air conditioning.

 

3. FILL IN THE BLANKS:

1. Automobiles are largest source of-- pollution in cities.

2 -----is major pollutant which decreases oxygen carrying capacity of haemoglobin of blood.

 

ANSWER KEY: PART-A

1. MULTIPLE CHOICE QUESTIONS:

 

1.(C ) Dr. Henry Antoine

2.(C ) Fly ash

3. (B) Chlorofluorocarbon

4. (A) Primary pollutant

5. (C ) Benzpyrene

 

2 TRUE/ FALSE:

1. False

2. True

3. True

 

 

3. FILL IN THE BLANKS:

1. Air

2. CO (carbon monoxide)

 

1.Name two pollution indicator plants?

2. Write major effect caused on human health by mobile combustion sources? 3What are secondary pollutants?

 

1. Define air pollution. Name two sources of air pollution. Describe four primary air pollutants and their sources.

 

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INTRODUCTION

Air pollution control is control of pollutants through different methods

to get pure air.

 

Many methods are adopted to purify air, are:Chemical methods, ESP, Plantation etc.

 

SEPARATION OF POLLUTANTS: Separation of pollutants can be done by different methods.

(a) Sulphur free lead free fuel should be used.

(b) Pollutants from automobiles can be decreased by

(i) By using more efficient fuel engines.

(ii) Multipoint fluid injection engines to reduce un-burnt hydrocarbon emission.

(iii) Catalytic converters: —- Platinum, palladium and rhodium act as catalysts.

Vehicles fitted with catalytic converters should use unleaded (lead free)petrol ;as

lead inactivates the catalytic converters. Catalytic converters can slash carbon

monoxide emission from 90 grams to 3-4 grams.



DEVICES TO CONTROL PARTICULATE MATTER:

ARRESTERS:

 

Arresters are of many types:

(i) ESP : Electrostatic Precipitators

(ii) CYCLONE SEPARATORS

(iii) TRAJECTORY SEPARATORS

(iv) GRAVITY SETTELING CHAMBERS

(V) FILTERS

 


It is most effective device to remove particulate pollutants. It can be employed to

separate hot as well as dry charged particles. These can remove size range of 5-

20 mm and to an extent of 99% but velocity of air must be low. Particle collecting plates ESP’s are shaken or vibrated and particles are shed to receiver basket. ESP’s are employed in thermal plants, industries of power generation,paper mills and sludge incineration.

 

CYCLONE SEPARATOR:Dust laden gas stream is transformed into combined vortex from centrifugal forces tend to derive the suspended particles to wall of body of separator.

 


BAG HOUSE FILTERS:In this device dust laden fumes are passed through the filtering devices.Filtering devices are made of porous mats of polyester, Teflon, wool or

cellulose etc. Particles are held by filters and clean gases pass through them.

 

SCRUBBERS:Scrubbers are formed from dry or wet packing material. These are used to

separate dust particles and toxic gases (especially SO2) from air.

 

Polluted air is forced in,simultaneously a counter current of water or lime moves in by spray nozzle . Water drops remove articulates as well as toxic gases while lime removes SO: as calcium sulphate or sulphite.Wet scrubbers are used in metallurgical industries.

 




USE OF CNG:CNG is called a cleaner fuel because it is mainly formed of methane with

smail percentage of other hydrocarbons. Its combustion releases fewer pollutants. WORLD'S largest fleet of CNG buses is in Delhi.

 

EURO NORMS:It refers to permissible emission level of both petrol and diesel vehicles It

was first implemented in European countries.

Similar norms were instituted by government of India are called Bharat stage emission standards (BSEB); to reduce vehicular pollution in indian cities. The Government of India announced a new auto fuel policy which includes stringent pollution - level norms e.g. Since 1 April,2000 Eurotnorms were introduced nationwide.Government of India announced to implement BS VI emission norms for four wheelers from 2023.December 2, is recalled as National Pollution prevention Day remembering Bhopal tragedy occured on 2" December, 1984 due to leakage of MIC (Methyl

isocynate) from fertilizer plant (union carbide) in atmosphere.In december1997 KYOTO SUMMIT was held in JAPAN where it was decided to reduce the emission of greenhouse gases to a level. COP Ill Kyoto protocol stated:

The European union will reduce its greenhouse emission by 8 pacet below the 1990 levels,the United states by 7 percent and Japan by 6

percent.

 

Twenty oneotherindustrialized countries will meet similar binding target and reductions would be achieved between 2008 and 2012 A.D.

Copenhagen Climate Summit was held in December 2009 (commonly callled

 

COP -9 at copenhagen Danish capital. Afair deal on climate change,alegally non binding agreement was adopted by world’s 17 most powerful nations thatthey won't allow the global temprature to rise by more than 2° C. But it was rejected by most of poor countries who wanted a maximum temperature rise to be fixed at 1.5°C.

 

LET US KNOW WHAT WE HAVE LEARNT

1. MULTIPLE CHOICE QUESTIONS:

 

(1) Montreal protocol which calls for appropriate action to protect the Ozone Layer from human activities was passed in year:

(a)1985

(b) 1986

(c) 1987

(d) 1988

 

2. Biodiesel is obtained from:

(a) Jatropa biloba

(b)cedrus

(c) Jatropa curcus

(d) None of these

 

3. Gaseous pollutants can be controlled by:

(a) Prolysis

(b) Arresters

(c) Incineration

(d) Adsorption

 

4. KYOTO PROTOCOL was endrosed at:

(a) COP III

(b)COP V

(c) COP VI

(d) COP IV

 

2. TRUE / FALSE

1. First earth summit was held in New Delhi.

2. In October 2019 government of India announced to implement BSVI emission

norms for vehicles across the country from 2023.

3. CNG is called cleaner fuel as its combustion releases fewer pollutants.

 

3. FILL IN THE BLANKS

1.Bhopal gas tragedy is associated with-—-—--—- --.

2.Device which separates the particulate matter on the basis of their charges

and due to development of corona effect is termed-—-- -.

 

ANSWER KEY: PART-A

1. (c)

2. (a)

3. (a)

4. (d)

 

1. FALSE

2. TRUE

3. TRUE

 

1. MIC (Methyl isocyanate)

2. ESP (Electrostatic precipitators)

 

Q 1. How does plantation helps to control air pollution? Name two plants that can

use nitrogen oxides?

Q2. Name materials used as filtering mats in Bag house filters.

Q3. Discuss steps taken in India to control air pollution.

 

Q.1 How can particulate matter be controlled? Explain role of Scrubbers?

 

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INTRODUCTION

All pollutants either affect vegetation or living beings. Adverse effects are increasing day by day. Climate is changing continuously.

Environmentalists are recording effects day by day.






causes mutations. Lethal in low doses, in low doses causes cancerous growth.

 

EFFECTS OF RADIOACTIVE POLUTANTS:

1. ER Bone cancer

 

2 MR. Damages WBC's, bone marrow, lymph nodes, skin cancer, sterility and defective eye sight. These may cause ionization of

various body fluids, chromosomal aberrations, and gene mutations.

 

3. EERE brings about nervous muscular and genetic changes

 

4 [EG Skin cancers and tumours to miners.

Apart from above effects many radioactive pollutants cause:Snow blindness, Inactivation of biomolecules, leukemia, Brain tumors,

Eye cataract, Suppression in immune system.

 

BAD EFFECTS OF ACID RAIN:

1. Acid rain caused by polluted air

2. Damages a number of heritage monuments e.g Taj Mahal in Agra

3. Below pH 5 rain causes death of planktons.

4. Kills soil microbial community.

 

EFFECT OF AIR POLLUTION ON CLIMATE:CFC’S brings depletion of ozone layer column; which allows high energy UV radiations in earth's atmosphere, a big damage to plants and animals.A vertical influence Temperature profile of atmosphere; leads to greenhouse

effect.Reduction in Rainfall; aerosols change physics of cloud formation.

 

GLOBAL WARMING:Greenhouse gases COz2, CHa, Oz, NO, NO2 absorb infrared radiations

from earth and re radiate them towards earth.

Increase in temperature caused by CO2 60%, CFCs 14% and oxides of nitrogen 6% recorded.

 

NEGATIVE IMPACTS OF GLOBAL WARMING;

1. ICE CAPS will melt and coastal areas round the globe will be in undated under increased level of oceans.

2. Grain production will be reduced.

3. Many areas will be warmer and drier (e.g. America)

4. One third of global forest will swept away.

5. Deserts will be increased.

6. Chances of flood, cyclones, and hurricanes will be increased.

7. Oceans acidification will be caused.

8. Extinction of more than one million species of animals and plants is expected upto 2050.

 

LET US KNOW WHAT WE HAVE LEARNT !!

PART:A VERY SHORT ANSWER TYPE QUESTIONS:

 

Q1. Lead concentration in blood is considered alarming ig it is:

(a)20 yg/100ml

(b) 30~ug/100ml

(c ) 4-6 ug/ 100ml

(d)10 yg/100ml

 

Q2. Anthracosis is caused by:

(a) Coal dust

(b) lron

(c) Cane fibre

(d) Silica

 

Q3. Freon gas causing stratospheric O3 depletion mainly released from:

(a) Refrigerators

(b) Automobiles

(c) Thermal Power Plants

(d) Steel Plants

 

 

Q4. Greenhouse gases cause global warming resulting into:

(a)lncrease of deserts

(b) Acidification of oceans

(c) Both (a) and (b)

(d) None of these

 

Q5. Thickness of ozone layer in a column of air from ground to top of atmosphere is measured in terms of:

(a)Decibel units

(b)Pascal units

(c) Svedberg units

(d) Dobson units

 

1. The CO2 causes asphyxial death due to oxygen starvation.

2. Photo chemical smog causes silvering, glazing and necrosis of leaf.

3. According to CPCB (central pollution control board) particulate pollutants of

4.5u m or more are harmful for human.

 

1. —---—---— breaks O3 enzymatically.

2. ---------- damages a number of heritage monuments.

 

1.(b)

2.(a)

3.(a)

4.(d)

 

1.False

2.True 

3.False

 

1. Active chlorine

2. Acid rain

 

PARTC SHORT ANSWER TYPE QUESTIONS:

Q 1.What is snow blindness?

Q 2. What are brown clouds?

Q 3 Write a note on ozone layer depletion.

 

PART: G LONG ANSWER TVPE QUESTIONS:

Q1. Define global warming? Write its effects?

 

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INTRODUCTION

WATER POLLUTION occurs when harmful substances - often chemicals or

microorganisms - contaminate a stream, river, lake, ocean, aquifer, or other body of water, degrading water quality and making it toxic to humans or the environment.

 

TYPES OF WATER POLLUTANTS:Water used for household, agricultural and industrial purposes when discharged after use is polluted with soluble, insoluble matter and even pathogens. Water pollutants can be classified as follows:

1. Biological: It includes pathogens like bacteria, viruses, worms and protozoa.

Most of these are added by excreta of animals.

 

2. Chemical: (a) Inorganic e.g. — phosphates, nitrates, fluorides and chlorides.

(b) Organic e.g. — phenols, plastics, dyes, pesticides and chloro compounds.

 

(c) Heavy Metals e.g. — cadmium, mercury, copper, zinc and their organometallic compounds.

 

3. Physical: Waste heats from industrial plants.

 

SOURCES OF WATER POLLUTION:

1. Urbanization: Anytime there are massive numbers of people conglomerated in one dense area, a physical disturbance of the land follows. The building of new roads, houses, and industries affect the cleanliness of the water through the use of detergents, chemicals, and exhaust emissions. When it rains, these chemicals are washed into the rivers and streams, and eventually into the

drinking water supply.

 

2. Industrial waste: Every day, industries produce large amounts of waste. This

waste contains pollutants and toxic chemicals such as mercury, lead,asbestos, sulphur and nitrates among other harmful chemicals. Most

industries lack a proper waste management system. This causes the waste to drain into water bodies such as rivers and the sea through waste disposal canals. These waste chemical change the color of the water, cause

eutrophication (excessive plant and algae growth) and change the water temperature and pose a serious hazard to humans, animals, and plants.

 


3. Domestic waste and sewage: Wastewater and sewage from household are also common causes of water pollution. Sewer water carried chemicals and harmful bacteria which pose serious health issues. Sewers from houses carry pathogens which cause diseases. Wastewater and sewer carry microorganisms which carry deadly diseases and are also breeding ground for disease carriers.

 


4. Marine Dumping: Every household produces garbage. It can be in the form of

papers, plastic bottles, glass, rubber, aluminium and also waste food. This

garbage is sometimes dumped in water bodies, and this causes water pollution. Some of these waste deposits take up to 200 years to decompose.When they enter the sea, not only do they cause pollution to the water but also

harm to water creatures.

 

5. Oil Spills: Oil is also one of the most dangerous causes of water pollution. Oil

waste from industries, ships, and machinery sometimes gains access to water bodies along with other waste products. Oil is not soluble with water and thus causes a layer that covers the water underneath. Besides polluting the water and making it harmful to humans, it also causes death to marine wildlife.

 


6. Pesticides and chemical fertilizers: These are products used by farmers to grow crops free of bacteria and insect infestation. While they may be usefulto plant life, they pose serious hazards to humans and animals if they gain access to water. This cause of water pollution mostly occurs when it rains. The chemicals mix with rainwater and flow to water bodies.

 

7. Radioactive waste discharge: There are nuclear power plants all around our

country, and the government allows “permissible levels” of radioactive water

to be released into the environment every day. And, while it’s permissible—it

doesn't mean it's safe. Likewise, accidents have been known to occur,releasing horribly high amounts of harmful radioactive chemicals to be released into the air, water, and soil.

 

LET US KNOW WHAT WE HAVE LEARNT!

PART: A Very Short Answer Type Questions:

A. MCQs:

 

1. Which of the following is the most harmful cause of oceanic water pollution?

(a) Plastic Waste

(b) Industrial Effluents

(c) Oil Spills

(d) Domestic Waste

 

2. Eutrophication by sewage pollution refers to the

(a) Nutrient enrichment of freshwater bodies

(b) Nutrient depletion of freshwater bodies

(c) Toxic chemical accumulation in freshwater bodies

(d) Heavy Metals accumulation in freshwater bodies

 

3. Waste water released from are not the sources of bacteria

(a) Sanitary

(b) Municipalities

(c) Tanning

(d) Industries

 

4. The is an important requirement of the aquatic life.

(a) Dissolved Nitrogen

(b) Dissolved Chlorine

(c) Dissolved Oxygen

(d) Dissolved Methane

 

5. Which of the following is not the inorganic water pollutant?

(a) Phenols

(b) Nitrates

(c) Chlorides

(d) Phosphates

 

B. True / False:

1. Mostly pollution of rivers takes place by discharge sewage/effluents.

2. Pollution from pesticides is part of surface run off type of pollution.

3. Radioactive water released in permissible limits is safe..

 

C. Fill in the Blanks:

1. Nutrient accelerates growth of algae.

2. Waste from sewers contains which cause deadly diseases.

 

ANSWER KEY OF PART-A

A. MCQs:

 

1. (c) Oil Spills — Oil spill in oceans make insoluble layer over water causing deaths of marine wildlife and making hazardous to humans.

 

2. (a) Nutrient enrichment of freshwater bodies — Eutrophication is nutrient

enrichment resulting in excessive plant and algae growth.

 

3. (d) Industries — Waste water released from the sanitary, municipalities,tanning and slaughtering plants are the sources of bacteria.

 

4. (c) Dissolved Oxygen — The dissolved oxygen is an important requirement of the aquatic life. They take oxygen from water to survive.

 

5. (a) Phenols — Phenols are the example of organic water pollutants

 

B. True / False:

1. True — River Pollution is majorly caused from discharge of effluents and sewage.

2. True — The chemicals mix with rainwater and flow to water bodies.

3. False — Radioactive water released in permissible limit doesn’t mean it's safe.

 

C. Fill in the Blanks:

1. Enrichment — Nutrient enrichment accelerates growth of algae and plants.

2. Pathogens — Pathogens are organisms that can produce diseases.

 

PART: B Short Answer Type Questions:

1. What is the difference between point and non-point sources?

2. How water pollutants are classified?

3. How urbanization is major source of water pollution?

 

PART: C Long Answer Type Questions:

1. What is water pollution? Explain different sources of water pollution.

 

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INTRODUCTION

 

WATER POLLUTION, to a larger extent, can be controlled by a variety of methods. Rather than releasing sewage waste into water bodies, it is better to treat them before discharge. Practicing this can reduce the initial toxicity and the remaining substances can be degraded and rendered harmless by the

water body itself. If the secondary treatment of water has been carried out,then this can be reused in sanitary systems and agricultural fields.Even chemical processes such as coagulation, ion exchange method, reverse osmosis, etc. will greatly reduce the level of water pollution.

 

CONTROL MEASURES OF WATER POLLUTION:

 

TREATMENT OF WASTE WATER:We know that large quantities of waste water are generated every day in cities and towns. A major component of this waste water is human excreta. This

municipal waste-water is also called sewage. It contains large amounts of organic matter and microbes. Many of which are pathogenic.

 

This cannot be discharged into natural water bodies like rivers and streams directly — you can understand {his treatment is carried out in two stages:

 

a) EE These treatment steps basically involve physical removal of particles — large and small — from the sewage through filtration and sedimentation. These are removed in stages; initially, floating debris is

removed by sequential filtration. Then the grit (soil and small pebbles) are

removed by sedimentation. All solids that settle form the primary sludge, and

the supernatant forms the effluent. The effluent from the primary settling tank

is taken for secondary treatment.

 

b) ee The primary effluent is passed into large aeration tanks where it is constantly agitated mechanically and air is pumped into it. This allows vigorous growth of useful aerobic microbes into flocs (masses of bacteria associated with fungal filaments to

form mesh like structures). While growing, these microbes consume the major part of the organic matter in the effluent. This significantly reduces the BOD (biochemical oxygen demand) of the effluent. BOD refers to the amount of the oxygen that would be consumed if all the organic matter in one litre of water were oxidised by bacteria. The sewage water is treated till the BOD is reduced.The BOD test measures the rate of uptake of oxygen by micro-organisms ina

sample of water and thus, indirectly, BOD is a measure of the organic matter present in the water. The greater the BOD of waste water, more is its polluting potential. Once the BOD of sewage or waste water is reduced significantly, the effluent is then passed into a settling tank where the bacterial ‘flocs’ are allowed to sediment. This sediment is called activated sludge. A small part of the activated sludge is pumped back into the aeration tank to serve as the

inoculum. The remaining major part of the sludge is pumped into large tanks

called anaerobic sludge digesters. Here, other kinds of bacteria, which grow

anaerobically, digest the bacteria and the fungi in the sludge. During this digestion, bacteria produce a mixture of gases such as methane, hydrogen sulphide and carbon dioxide. These gases form biogas and can be used as source of energy as it is  inflammable. The effluent from the secondary

treatment plant is generally released into natural water bodies like rivers and

streams.

 


Trickling Filter method is another method of Secondary Treatment. In this,sewage water passes through thick bed of gravel stones so that bacteria consume most of the organic matter.

 


es 10 this, salts like nitrates and phosphates are removed by precipitation technique. It may involve processes like biological nutrient removal, disinfection and removal of micro pollutants. Water is now pure enough to drink.

 

Gobar Gas plant can be used for prevention and control of water pollution and

to recycle the various kinds of waste products. Some other recommended

methods are:

 

a) Compositing kills most of the pathogens and also ripens the dung into manure.

b) From jute wastes, hardboard can be prepared.

c) Coconut and other agricultural wastes can be used for the manufacture of paper and board.

 

CONTROLLED USE OF PESTICIDES AND FERTILIZERS:

Minimum amounts of pesticides should be applied so that no surplus remains in the soil. Only less stable compounds should be used in manufacturing biocides.

REVERSE OSMOSIS:By this technique, brackish water is demineralized by pumping it through a semipermeable membrane under strong pressure.Thermal pollution can be checked and controlled by employing heat or dry

cooling towers.

 

WATER HYACINTH:Water Hyacinth removes biological and chemical pollutants. It also removes heavy metals like Cd, Hg, Pb and Ni.

 

LET US KNOW WHAT WE HAVE LEARNT!

PART: A Very Short Answer Type Questions:

A. MCQs:

 

1. What is the full form of BOD?

(a) Biochemical Oxygen Demand

(b) Biological Oxygen Demand

(c) Biometric Oxygen Deep water

(d) Biological Oxygen Deep water

2. Water Pollution Act was introduced in which year?

(a) 1973

(b) 1971

(c) 1974

(d) 1984

 

3. Infiltration, the amount of dissolved solids passing through the filters

is:

(a) Difference between total solids and suspended solids

(b) Sum of total solids and suspended solids

(c) Independent of suspended solids

(d) None of the above

 

4. The Total dissolved solids (TDS) can be reduced by:

(a) Distillation

(b) Reverse osmosis

(c) lon exchange

(d) All of the above

 

5. In tertiary treatment nitrates and phosphates are removed by:

(a) Precipitation

(b) Sedimentation

(c) Sequential filtration

(d) None of the above

 

B. True / False:

1. Trickling filter method is a primary treatment method of waste water treatment.

2. Coconut and other agricultural wastes can be used for the manufacture of paper and board.

3. In primary filtration method, small pebbles are removed by sequential filtration method.

 

C. Fill in the Blanks:

1. The the BOD of waste water, more is its polluting potential.

2. Brackish water is demineralised by pumping it through a semipermeable membrane under strong pressure, this method is known as :

 

ANSWER KEY OF PART -A

A. MCQs:

 

1. (a) Biochemical Oxygen Demand - BOD is Biochemical Oxygen Demand which is a measure of the organic matter present in the water.

 

2. (c) 1974 — Water Pollution Act was introduced in 1974 for prevention and

control of water pollution, and for the maintaining and restoring of wholesomeness of water India.

 

3. (a) Difference between total solids and suspended solids — In filtration, the

amount of dissolved solids passing through the filters is Difference between total solids and suspended solids.

 

4. (d) All of the above — Reverse Osmosis, lon Exchange and Distillation all are processes for reducing TDS in water.

 

5. (a) Precipitation — Salts like nitrates and phosphates are removed by precipitation technique.

 

B. True / False:

1. False — Trickling Filter method is another method of Secondary Treatment.In this, sewage water passes through thick bed of gravel stones so that bacteria consume most of the organic matter.

2. True — Coconut and other agricultural wastes can be used for the manufacture of paper and board.

3. False — Floating debris is removed by sequential filtration and then the grit

(soil and small pebbles) are removed by sedimentation.

 

C. Fill in the Blanks:

1. greater - The greater the BOD of waste water, more is it's polluting potential.

 

2. Reverse osmosis — The brackish water is demineralized by pumping it through a semipermeable membrane under strong pressure, this method is known as reverse osmosis.

 

PART: B Short Answer Type Questions:

1. What is trickling filter method?

2. How waste water can be recycled? Give few examples.

3. How water pollution can be prevented?

 

PART: C Long Answer Type Questions:

1. Explain all the methods of treatment of water pollution.

 

A189

 

INTRODUCTION

 

WATER POLLUTION adversely affects the health and life of man, animals and plants alike. Polluted water is also harmful for agriculture as it adversely affects the crops and the soil fertility. Pollution of sea water damages the oceanic life.

 

As we work with water in our homes in the cities and towns, we wash everything into drains. Have you ever wondered where the sewage that comes out of our houses goes? What happens in villages? Is the sewage treated before being transported to the nearest river and mixed with it? A mere 0.1

per cent impurities make domestic sewage unfit for human use.

 

EFFECTS OF WATER POLLUTANTS:The effect of water pollution depends upon the type of pollutants and its concentration. Also, the location of water bodies is an important factor to determine the levels of pollution. Water bodies in the vicinity of urban areas

are extremely polluted. This is the result of dumping garbage and toxic chemicals by industrial and commercial establishments.

Following are the adverse effects of various pollutants:

 

1. Effect of Organic waste and Domestic Sewage:Domestic sewage primarily contains biodegradable organic matter, which

readily decomposes — thanks to bacteria and other micro-organisms, which can multiply by using these organic substances as substrates and hence utilize some of the components of sewage. It is possible to estimate the amount of biodegradable organic matter in sewage water by measuring Biochemical Oxygen Demand (BOD).



Micro-organisms involved in biodegradation of organic matter in the receiving water body consume a lot of oxygen, and as a result there is a sharp decline in dissolved oxygen downstream from the point of sewage discharge. This causes mortality of fisn and other aquatic creatures. Deoxygenation of water by biodegradation of organic wastes produces foul smell in water bodies and make it unfit for human consumption. Pathogen contaminated water causes infectious diseases like cholera, jaundice, typhoid, dysentery, hepatitis etc. According to Central Water Health Engineering Institute, about 50-60% Indian population suffers from water borne diseases and about 30-40% deaths occur due to water pollution. Also these wastes form scum and sludge in polluted water making it unfit for industrial use.

 

2. Effect. of Nutrients on Water Quality:

Water supports aquatic life because of the presence of nutrients in it. Here the

primary focus is on fertilizing chemicals such as nitrates and phosphates.These are contributed by sewage, agricultural run-off and run-off from un sewered residential areas. Although nutrients are important for plant growth,too much of nutrients encourage the overabundance of plant life and can result in environmental damage called ‘Eutrophication’. Due to this excessive growth of planktonic (free flowing) algae takes places which is also called “Algal

bloom” which imparts a distinct colour to the water bodies.



Algal blooms cause deterioration of the water quality and fish mortality. Some

bloom-forming algae are extremely toxic to human beings and animals.Plants having beautiful mauve-colored flowers which were introduced into India for their lovely flowers have caused havoc by their excessive growth by causing blocks in our waterways. They grow faster than our ability to remove

them. These are plants of water hyacinth (Eichhornia crassipes), the world’s

most problematic aquatic weed, also called ‘Terror of Bengal’. They grow abundantly in eutrophic water bodies, and lead to an imbalance in the ecosystem dynamics of the water body.

 

3. Effect of High Dissolved Solids (TDS):

Water is the best solvent and can dissolve a large variety of substances which

come in its contact. The amount of dissolved solid is a very important consideration in determining its suitability for drinking, irrigation and industrial uses. In general, waters with total dissolved solids of less than 500 mg/Aitre are most suitable for drinking purposes.Higher amount of dissolved solids may lead to impairment of physiological processes in human body. Dissolved solid is very important criteria for irrigation. This is due to the fact dissolved solid accumulates on the ground

resulting in salinization of soil.In this way it renders the agricultural land non-productive. Dissolved solids are harmful for industries also because they form scales, cause foaming in boilers,accelerate corrosion and interfere with the colour and taste of many finished products.

 


4. Effect of Toxic pollutants:Waste water from industries like petroleum, paper manufacturing, metal extraction and processing, chemical manufacturing, etc., often contain toxic substances, notably, heavy metals (defined as elements with density > 5 g/cm3 such as mercury, cadmium, copper, lead, etc.) and a variety of organic

compounds.

 


Minamata disease: Due to consumption of mercury contaminated fishes of Minamata Bay,

Minamata disease appeared in Japan

in 1962.

 

Itaiitai disease: Due to consumption of Cadmium contaminated rice, this disease appeared in Japan which causes liver and lung cancer.A few toxic substances, often present

in industrial waste waters, can undergo biological magnification (Biomagnification) in the aquatic food chain. Biomagnification refers to increase in concentration of the

toxicant at successive trophic levels.

This happens because a_ toxic substance accumulated by = an organism cannot be metabolised or excreted, and is thus passed on to the next higher trophic level. This

phenomenon is well known for mercury and DDT.

DDT(Dichloro Diphenyl Trichloroethane) interferes with the calcium metabolism and egg-shell formation in many birds. The shells remain thin and undergo premature break by bird's weight during incubation. This decreases bird population. This was the reason for banning of DDT in the United States in 1972.

 

5. Effects of Thermal Discharges on Water Quality:The discharge of cooling water from industrial and commercial operations

generally heats up the aquatic environment. Organisms may become physiologically stress or may even be killed when exposed to heated water. If water heating is supplemented by the summer heat, the impact on aquatic

environment can be disastrous.Thermal pollution also causes a decrease on the driving force or oxygenation which may directly kill aquatic life through asphyxiation. If toxic pollutants are

present in the aquatic environment, thermal pollution may increase their toxicity to the aquatic life. Bioavailability of many pollutants may also increase due to thermal pollution, which may ultimately adversely affect the aquatic life.

 

 

LET US KNOW WHAT WE HAVE LEARNT!

PART: A Very Short Answer Type Questions:

MCQs:

1. Which of the following is the major reason for algal bloom?

(a) Presence of Heavy Metals

(b) Contamination by Pathogens

(c) Eutrophication

(d) Soil Erosion

 

2. Minamata Disease in Japan was caused due to?

(a) Cadmium

(b) Mercury

(c) Copper

(d) Lead

 

3. The disappearance of the plants and animals is due to____in water?

(a) Nitrogen Depletion

(b) Chlorine Depletion

(c) Oxygen Depletion

(d) Ozone Depletion

 

4. Which of the following causes Biomagnification?

(a) SO»

(b) Mercury

(c) DDT

(d) Both (b) & (c)

 

5. Which of the following is a water borne disease?

(a) Typhoid

(b) Cholera

(c) Jaundice

(d) All of the above

 

True / False:

1. Itaidtai disease was caused due to cadmium contaminated rice.

2. Polluted water creates imbalance in the ecosystem.

3. DDT is Dichloro Dipheny!Tetrachloroethane.

 

Fill in the Blanks:

1. Heavy Metals are defined as elements with density .

2. Total dissolved solids of less than are most suitable for drinking purposes.

 

ANSWER KEY OF PART-A

MCQs:

 

1. (c) Eutrophication — too much of nutrients encourage the overabundance of plant life which results in algal bloom.

 

2. (b) Mercury — Due to consumption of mercury contaminated fishes from Minamata Bay, Minamata disease was caused.

 

3. (c) Oxygen Depletion — Plants and animals die to non-availability of oxygen.

 

4. (d) Both (b) & (c) — Biomagnification is caused due to inhalation ofmercury and DDT.

 

5. (d) All of these — Typhoid, Cholera and Jaundice are all water borne diseases as these are caused from polluted water.

 

True / False:

1. True — Itai-Itai disease was caused due to consumption of cadmium contaminated rice in Japan.

 

2. True — Polluted water disturbs the ecosystem causing imbalance.

 

3. False — DDT is Dichloro Diphenyl Tricholorethane.

 

Fill in the Blanks:

1. 5g/cc — Elements having density higher than 5mg/itre are classified as heavy metals.

2. 500mg/litre - Water having TDS less than 500mg/itre are fit for drinking.

 

PART: B Short Answer Type Questions:

1. What is Biomagnification and how it effects food chain?

2. What caused Algal Bloom? Explain briefly.

3. What do you mean by BOD and what is used for?

 

PART: C Long Answer Type Questions:

1. Explain the various effects of water pollutants.

 

A190

 

INTRODUCTION

 

In the wake of green revolution, use of inorganic fertilizers and pesticides has

increased manifold for enhancing crop production. Pesticides, herbicides, fungicides,etc., are being increasingly used. Those incidentally, are also toxic to non-target organisms that are important components of the soil ecosystem. Do you think these can be biomagnified in the terrestrial ecosystems?

 

We know what the addition of Increasing amounts of chemical fertilizers can do to aquatic ecosystems via-a-vis eutrophication. The current problems in agriculture are, therefore, extremely greate.

 

What are Agrochemicals?

Agrochemicals are pesticides, herbicides or fertilizers used for the management of

ecosystem in agricultural sectors.

 


Agrochemical (Crop protector):Pesticides: Pesticide is a chemical or a substance used to destroy or control some types of plants or organisms also known as pests, which are harmful to cultivated plants or to animals.

 

Insecticide: It is used to destroy insects. Insecticides can be ovicides that kill eggs,

larvicides to kill larvae.

 

Pesticides examples: Organochlorines, organophosphates, carbamates and pyrethroids.

 

Herbicides: It is used to control or kill weeds and herbs.

 

Herbicides examples: Gramoxone and glyphosate.

 

Agrochemicals:

Fertilizer: These are chemical compounds used for promoting plant growth.Fertilizers can be categorized into two categories:Organic fertilizers are naturally existing substances prepared through natural processes.

 

Inorganic fertilizer, also referred to as synthetic fertilizers are manufactured artificial using chemical processes by utilizing natural deposits, which are altered chemically.

 

Hormones/Growth Agents :Are of Endogenous origin and are synthesized by plants.

 

These are Growth regulators performing function in overall development of plant.

 

Liming and acidifying agents: Soils sometimes can be too acidic or too alkaline for

proper growth of crops. In these cases, liming and acidifying products are added to

soil to adjust its pH. When the soil is too acidic calcite on the form of powdered

limestone is added primarily, whereas for more alkaline soil sulfur compounds are

added to neutralize.

 


Benefits: -

Agrochemicals are used to improve quality and quantity of food.

 

Improve plant nutrition.

 

Improve economic production.

 

Improve quality of life.

 



Effects on Soil:-Soil health is the capacity of soil to function within ecosystem and land

use boundaries, to sustain productivity maintain environmental quality, and promote plant and animal health.

 


Negative Impacts of Agrochemicals on Soil Health:-

Kills beneficial organisms.

Increase in nitrate levels of soil.

Damage natural make up of soil.

Alters the pH.

Decrease soil quality.

Kills soil organisms.

Toxic to microbes.

Toxicity of availability of nutrients.

Kills earthworms.

Growth regulators.

Residual effect.

Toxic to soil organisms.

 

Effects on Water:-

Water becomes unfit for drinking.

 

The runoff of agrochemicals into

streams, lakes, and other surface waters

can increase the growth of algae.

 

Eutrophication — Change in quality and

composition of aquatic ecosystems by

accumulation of excessive chemicals in

water bodies.

 

Polluted water leading to the death of

fish and other aquatic animals.

 

Excessive use of agrochemicals has led

to the contamination of groundwater.

 


Effects on air:-

Pesticides can contribute to air pollution.

 

Pesticides drift occurs when pesticides suspended in the air as particles are carried

by wind to other areas.

 

Weather conditions at the time of application as well as temperature and relative

humidity change the spread of the pesticide in the air.

 

Low relative humidity and high temperature result in more spray evaporating.

 

The polluted air is inhaled by humans end up with different diseases.

 

Effect on Humans:

It causes variety of health effects from simple skin and eye irritation.

 

Effects nervous system, causes cancer and also reproductive problems.

 

Can cause nerve damage, hormones disorders and neurotoxicity.

 


Pesticides entering human body:-

Pesticides can enter the body through inhalation of aerosols, dust and

vapors that contain pesticides; through oral exposure by consuming food/water; and through skin exposure by direct contact.

 

The effects of pesticides on human health depend on the toxicity of the chemical and the length and magnitude of exposure.

 

Farm workers and their family experience the greatest exposure to agricultural pesticides through direct contact.

 

Pesticide exposure can cause a variety of adverse health effects, ranging from

simple irritation of the skin and eyes.

 

It also affects the nervous system, mimicking hormones causing reproductive problems, and also causing cancer.

 

Children are more susceptible and sensitive to pesticides, because they are still

developing and have a weaker immune system than adults.

 

 


FIFRA:-(FEDERAL INSECTICIDE, FUNGICIDE & RODENTICIDE ACT)

twas first established in 1947 & revised as recently as 1996.

It states what must be on a pesticide label & requires registration of all pesticides>

 

FFDCA:-(FEDERAL FOOD, DRUG, & COSMETIC ACT)

Strengthened in 1996

Sets pesticide tolerance levels

 

“Let Us Know What We Have Learnt”

PART- A VERY SHORT ANSWER TYPE QUESTIONS:

a. Multiple choice questions:

 

1. Which one is an agrochemical waste?

(a) Mobile

(b) Pesticides

(c) Sludge

(d) scrap

 

2. Which kind of pollution is caused mainly due to agrochemical waste?

(a) Soil

(b) Sound

(c) Water

(d) Air

 

3. Which one of the following agrochemical waste is added in the soil to increase the growth of plants?

(a) Pesticides

(b) Fertilizers

(c) Water

(d) compost

 

4. FIFRA was established in year:

(a) 1947

(b) 1950

(c)1954

(d) 2000

 

5. Agrochemicals that control weeds are:

(a) Weedicides

(b) Insecticides

(c) Fertilizer

(d) Compost

 

b. True/False:

1. Agrochemicals are chemicals which are used in agriculture.

2. Insecticides are most widely consumed agrochemical.

3. FFDCA sets pesticide tolerance level.

 

c. Fill up:

1. Agrochemicals alter the of soil.

2. Change in quality and composition of aquatic ecosystem due to agrochemicals is

 

ANSWER KEY: PART -A

a. MCQs:

 

1. Pesticides (b)Any chemical that harms the ecosystem are agrochemical wastes.

2. Soil (a)An agrochemical is a chemical used to help manage agriculture area. When thi

chemical harms the ecosystem it is said to be waste. This waste leads to pollution of

soil.

3. Fertilizers (b)Fertilizers are the agrochemical waste is added in the soil to increase the growth of plants.

4. 1947 (a)Federal Insecticide, Fungicide & Rodenticide Act was first established in 1947

5. Weedicides (a)Weedicides control weeds.

 

b. True/False:

1. True.

2. True

3. True

 

 

c. Fill ups:

1.pH

2. Eutrophication

 

PART-B SHORT ANSWER TYPE QUESTIONS:

1. Is there any harmful effect of agrochemical rise on soil micro-organisms?

2. Discuss 2 types of agrochemicals?

3. How does use of agrochemical affect the quality of ground water in crop farming

areas?

 

PART-C LONG ANSWER TYPES OF QUESTIONS:

1. What are the effects of agrochemical on human health?

 

A191

 

INTRODUCTION

Solid waste is any material unused or rejected as worthless or unwanted.

Or Solid waste refers to everything that goes out in trash.

 


In this topic we will discuss about how solid waste can be managed.

 

Defination:Solid waste management may be defined as discipline associated with the control Of generation, storage , collection, transfer, processing and disposal of solid waste.

 

Basic Principles:

1. Segregation of biodegradable and recyclable waste at household.

 

2. Reuse of recyclable & processed end product.

 

3. Treatment of waste at household and community systems to be promoted only if space is a constraint.

 

4. Technology choices to be limited to those that are simple, easy to maintain & not very

capital and operation intensive.

 


1.Segregation can be done in two ways :

(i)On-site segregation at the point of generation of wastes:All the wastes generated at source are required to be segregated in two different bins.

 Blue-coloured bin/receptacle will be for non-biodegradable waste.

 


(ii) Central processing facility:

Itinvolves separation of different kinds of wastes by screening,air classifying and magnetic separators.Biodegradable solid wastes are disposed by composting while non-

biodegradable solid wastes are disposed by incineration, land filling,pyrolysis, etc.

 

2. Dumping: Dumping is simple and economical method to manage the urban solid wastes and reclaim the low-lying areas for better use.

 

3. Composting: In this, the biodegradable organic matter of solid wastes is

digested anaerobically or aerobically by microbial action and converted into humus

and stable mineral compounds.

 

4. Incineration : It involves the

aerobic burning of the non-biodegradable but combustible constituents of solid wastes like

garbage, rubbish and dead animals in the properly-constructed hearth of furnaces at high temperature (>670°C). It is ideal for disposal of hospital and e-wastes. The final

products are ashes and clinkers.



But incineration technique also has certain drawbacks:

 (i) Incinerator ash is toxic and contains toxic chemicals like Dioxin and Mercury.

(ii) Its Leachate can pollute ground water.

 

5. Pyrolysis: It involves anaerobic

destructive distillation of the non-

biodegradable and combustible constituents of the solid wastes at high temperature (650° to 1000: C)in a pyrolysis chamber so as to recover the chemical constituents and chemical energy of organic wastes.

 

6. Recycling of wastes:Paper Waste Paper of old books, newspapers, answer books, magazines, etc.are recycled to produce newspaper in the paper mills

 

2. Agricultural wastes can be recycled to produce useful products e.g. paper and

hard board from coconut waste, jute waste, cotton stalks, bagasse of sugarcane

stem of rice, etc., livestock feed from paddy, husk, etc.

 

3. Food processing and cannery wastes can be fermented to produce organic acids.

 

4. Seeds of Sal (Shorea robusta), Mahua (Medhuca), Neem (Azadirachtaindica)

can be used to extract oil from them. These oil cakes may be used both as fodder and manure

 

5. Composting of organic wastes produces manure.

 

6. Gobar gas plants use cow dung and other organic wastes of farm houses to provide manure for fields and biogas for domestic use.

 

7. Sludge of sewage treatment plants can be burnt to produce electricity.

 


Polyblend :- A remedy for plastic waste.

AHMED KHAN developed Polyblend. It is a fine power of recycled modified plastic.

 


 

“LET US KNOW WHAT WE HAVE LEARNT!”

PART: A Very short Answer Type Questions :-

(A) Multiple choice questions :

 

Ques 1 : Which of the following can be recycled many times?

(a)Plastic

(b)Wood

(c) Organic materials

(d) Aluminum

 

Ques 2 : What is called for the process of burning municipal solid waste in properly Designed furnace under suitable temperature and operating conditions?

(a) Landfill

(b) Recycling

(c) Vermicomposting

(d) Incineration

 

Ques 3: Why plastics are difficult to recycle?

(a) Because it is very hard material.

(b) Because it is very adhesive in nature.

(c) Because of different types of polymer resins.

(d) Because of different sizes of plastics.

 

Ques 4: When the matter present inside the sanitary landfill breaks down,which gas is generated?

(a) Methane

(b) Nitrogen

(c)Hydrogen

(d) All the above

 

Ques 5: Municipal solid waste is the term used to describe which kind of solid waste?

(a) Hazardous

(b) Toxic

(c) Non-Hazardous

(d) Non-Toxic

 

(B) True/ False:

(1) Managing waste is the responsibility of the Government.

(2)Waste reduction can be achieved by technology.

(3) Blue colored bin is used for Non-biodegradable waste.

 

(C) Fill in the blanks:

1. Polyblend is developed by .

2. of organic wastes produces manure

 

 

 

ANSWER KEY: PART -A

(A) Multiple choice questions:

Answer 1:- (d)

Recycling is reusing some components of waste that has some economic value.Aluminium can be recycled many times as mining of new Al is expensive.

 

Answer 2: (d)

Incineration is a chemical process in which waste is combined with CO2+ HzO At suitable temperature and operating condition.

 

Answer 3: (c)

Plastics are made of different types of polymer resins which cannot be recycled

together. Since each type has a distinct chemical composition

 

Answer 4: (a)

Decomposition of waste inside landfill produces methane gas which is used as fuel.

 

Answer 5: (a)

MSW is used to describe most of hazardous solid waste from village, or city that Require daily collection and transport to disposal site.

 

(B) True / False:

1. False

2. True

3. True

 

(C) Fillin the blanks:

1. Ahmed Khan

2. Composting

 

PART: B_ Short Answer type questions:

Ques 1: What is waste management?

Ques 2: What are the common methods of waste disposal?

Ques 3: What are the common recyclable materials that can be recycle from household

Garbage.

 

PART: C Long Answer type questions:

Ques 1: Explain the process of compositing?

 

A192

 

INTRODUCTION

Radioactive pollution is caused by radioactive wastes. Radioactive

wastes are those wastes which release radioactivity. (emission of alpha

particles, Beta Particles or gamma rays) from nuclides of their elements. Traces of radioactive elements occur in a number of products e.g. polonium in tobacco, radon indoors, several ores.

 

PROBLEMS RELATED TO USE OF RADIOACTIVE ELEMENTS & NUCLEAR ENERGY :At one time nuclear energy was considerd to be quite safe and non-polluting source of electricity generation. Later on, it was found that

there are a number of inherent problems related to use of radioactive elements and nuclear energy.

 

1. ACCIDENTS :- Nuclear reactors have several inbuilt safety measures.Even then meltdown and accidental leakages do occur e.g. Three

Mile Island, Chernobyl(1986), Fukushima.

 

2. RADIOACTIVE WASTES :They are produced from a number of sources

|. Nuclear testing laboratories.

ll. Minor leakage from nuclear powerplants.

lll. Wastes from Uranium mines.

IV. As natural minor components of ores and coal.

V. Spillage from radioisotopes used in research and medicine.

VI. Spent fuel of atomic reactors.

Radioactive substances often have a long half-life e.g. 28 years in case of

Strontium -90 and 30 years for caesium -137. They persist in the soil for a long period, enter plants and harm human being as well as animals. P-32 and 1-125 get concentrated in slime sludge and microorganisms , pass into fish and other aquatic life and from there to humans.

 

RADIOACTIVITY LEVELS :- Depending upon the amount of radioactivity,there are three types of radioactivewastes — low level,intermediate level and high level.

 

 

LOW LEVEL RADIATION :-

i. Extremely small amount of radioactivity enters coolant water used in atomic reactors and ponds used for quenching heat and radioactivity of spent fuel. It undergoes biomagnification to some 75,000 times in birds.

 

iii Radioactive wastes are produced by testing laboratories, irradiation centres for induction of mutations, study of metabolic pathways,radiotherapy and other centres using radioisotopes.

 

INTERMEDIATE LEVEL RADIATION - It is radiation which is not accompanied by liberation of heat. There is not much problem in disposal of wastes emitting intermediate level radiations. Small amounts of these radioactive wastes occur in all ores. If not dumped properly, the radioactive wastes can kill vegetation and cause irreparable injuries to human and animals.

 

HIGH LEVEL RADIATIONS: -They are highly destructive radiations which develop

due to:

i. Accidental leakage or meltdown of atomic reactors.

ii. Spent fuel of atomic reactors.

 

High level wastes produce a lot of heat and large amount of radiations. Even short duration exposure to such high level radiations cause loss of hairs nails,

subcutaneous bleeding and damage to all organs. The radiations cause tumors,cancers and genetic deformities.

 

High level wastes require special protective shields during handling &transport. They need cooling. The wastes are first concentrated to reduce their bulk, kept in thick leak-proof containers and dumped for 50-100 years in small ponds in the premises of nuclear plants. Their Storage dissipates major part of both heat and radioactivity. The weakened radioactive wastes kept in shielded

containers are then buried 500 m down deep inside earth. Sea bottom is also used

for it. However, environmentalists are opposing both the methods of disposal.

 

LET US KNOW WHAT WE HAVE LEARNT!

PART —A VERY SHORT ANSWER TYPE QUESTIONS:

1. MULTIPLE CHOICE QUESTIONS;

 

1. Radiations can cause:

a) Cardiac disease

b) Haemophilia

c) Cancer

d) Bonemarrow disease.

 

2. You can reduce your exposure to radiation by doing the following:

a) Increasing your distance from the source.

b) Decreasing the amount of time near the source.

c) Provide shielding between yourself and the source.

d) All of the above.

 

3. Radioactive pollution is:

a) Generally man made.

b) Always naturally occurring.

c) Not dangerous.

d) Usually caused by radon gas.

 

4. When did Chernobyl disaster occured?

a) 1976

b) 1986

c) 1996

d) 2000

 

5. What is the main purpose of nuclear energy?

a) To kill the enemy nation.

b) To waste the excessive energy.

c) To use it as an alternate source of energy.

d) To cause mutation for people who are working.

 

2. TRUE/FALSE:

1. Radioactive wastes are those wastes, which release UV- radiations.

2. Intermediate level radiations are accompanied by liberation of lot of heat.

3. Low level radiations are used in irradiation centres for inducing mutations.

 

3. FILL IN THE BLANKS:

1) Half — life of strontium 90 is ...............

2) Radioactive wastes emit ............;c:ccceeee AMG. cece cece eee

particles from the nuclides of their elements.

 

 

ANSWER KEY: PART -A

(a) MCQs:

 

1. (c) The radioactive wastes produce radiations which cause cancerin human beings.

 

2. (d) Staying away from the source of radiation & providing shielding can reduce the exposure to radiation.

 

3. (a) Radioactive pollution caused by radioactive wastes are generated by man.

 

4. (b) On 25 April, 1986 in Chernobyl, an explosion occurred in nuclear reactor.

 

5. (c) Nuclear energy is used to produce electric energy in Nuclear Power Plants.

 

(b) TRUE/FALSE:

1. False — Radioactive wastes are those wastes which release Alpha ,Beta or Gamma rays.

2. False — Intermediate level radiations are not accompanied by liberation of heat.

3. True.

 

 

(C) FILL IN THE BLANKS:

1. 28 years.

2. Alpha -particles, Beta -Particles and Gamma -Particles.

 

PART-B SHORT ANSWER TYPE QUESTIONS:

1) Name one incident of accidental leakage from nuclear reactors.

2) What are radioactive wastes?

3) Describe the methods of handling of radioactive wastes.

 

PART-C LONG ANSWER TYPE QUESTIONS:

1. Discuss the various problems related to use of radioactive wastes.

 

A193

 

INTRODUCTION

Greenhouse effect term is derived from greenhouse which looks like a small glass house & is used for growing plants during winters. In a greenhouse the glass panel lets the light in but does not allow heat to

escape. Therefore the greenhouse warms up. Similar is naturally occurring in greenhouse effect which is responsible for heating earth’s surface & atmosphere. Increase in the level of greenhouse gases has led to

considerable heating of earth leading to global warming.

 

GREEN HOUSE EFFECT :-

1. Without greenhouse effect the average temperature at surface of earth would have been a chilly -18°C, rather than present average of 15°C.

 

2.Almost half of incoming solar radiations with infrared radiation fall on earth’s surface heating it, while a small proportion is reflected back.

 

3. Earth’s surface re-emits heat in the form of infra-red radiation but part of

this is absorbed by gases like CO2 & Methane.

 

4. The molecules of these gases radiate heat energy. & major part of which again comes to earth’s surface, thus heating it up once again.

 

5. The cycle is repeated many times & surface of earth is warmed up.

 

GREEN HOUSE GASES :- The gases which are transparent to solar radiation but retain & partially reflect back long wave heat radiations are called greenhouse gases. The various greenhouse gases are CO2, CH,, CFC’s

& nitrous oxide.

1. €O2:- The rise in COz in the atmosphere is due to large scale deforestation, change in land use & large scale combustion of fossil fuels.

 

2. METHANE :- Methane is produced by incomplete biomass combustion,incomplete decomposition by anaerobic methanogens. Flooded paddy fields, marshes, cattle are the major sources of this gas.

 

3. CFC’s :-They are synthetic gaseous compounds of carbon & halogen which are odourless, non-toxic, noninflammable, chemically inert propellants used in aerosol cans & jet fuels, refrigerants in air conditioner & refrigerators.

 

4. NITROUS OXIDE :- It is produced by combustion of nitrogen rich fuels,livestock wastes, breakdown of nitrogen fertilizer in soil, nitrate contaminated water etc.

Out of these, COz & CH, are the major Greenhouse gases.

 

GLOBAL WARMING:Increase in the level of greenhouse gases has led to considerable heating of earth leading to global warming. During the past century the temperature of

earth has increased by 0.6°C .

 

HARMFUL EFFECTS OF GLOBAL WARMING:- Scientiests believe that this rise in temperature is leading to deleterious changes in environment & resulting in odd climatic changes (eg. El Nino effect).

 

It has increased the melting of polar ice-caps. Over many years, this will result in a rise in sea level that can submerge many coasts.

 

Pattern of air-mass movement will change. Precipitation will increase at higher latitudes both in summer & winter. Winter precipitation will be reduced at lower latitudes.

 

Frequency of droughts & floods will increase.

 

Rise in temperature of 2-5°C Will push temperate range by some 250- 600 km pole-wards. Many tree species & other organisms which are sensitive to temperature will die out.

 

Rise in temperature is detrimental to crop productivity due to increase in respiration, greater growth of weeds, eruption of diseases & pests.

 

Warming of troposphere is accompanied by cooling of upper strata of atmosphere. Cooling of stratosphere will lead to increase the size of ozone hole while cooling in thermosphere will disrupt radio communications.

 

STRATEGIES TO CONTROL GLOBAL WARMING:-

1. Cutting down use of fossil fuel.

2. Improving efficiency fo energy usage.

3. Reducing deforestation.

4. Planting trees.

5. Slowing down the growth of human population.

6. Complete replacement of CFC’s with substitutes that have little effect on ozone & Global Warming.

 

LET US KNOWN WHAT WE HAVE LEARNT!

PART:A VERY SHORT ANSWER TYPE QUESTIONS:

A. MCQs:

 

1. Greenhouse effect is caused by:

(a) Green Plants

(b) Infrared rays

(c) UV rays

(d) X-rays.

 

 

2. Global warming can be controlled by:

a) Increasing deforestation, reducing efficiency of energy use.

b) Reducing deforestation, cutting down use of fossil fuels.

c) Reducing deforestation, increasing use of fossil fuels.

d) Increasing deforestation, slowing down the growth of human population.

 

3. Which is not a greenhouse gas?

(a) Methane

(b) CO2

(c) CFC’s

(d) Nitrogen.

 

4. Greenhouse effect is increasing due to:

(a) Increasing CO2z Concentration.

(b) Increasing SO2 Concentration.

(c) Hole in ozone layer.

(d) Increasing concentration of Nitrogen.

 

5. The two gases making highest relative contribution to greenhouse gases:

(a) CHa& N20

(b) CFC’s & N2O

(c) CO2 & N2O

(d) CO2&CH,

 

B. TRUE/FALSE:

1. UV radiations are responsible for Green House effect.

2. The average temperature of earth’s surface is 15°C

3. Major greenhouse gases are COz & CHa.

 

C. FILL IN THE BLANKS:

a. Increase is average temperature of earth’s surface is called ................

b. Cooling of stratosphere will increase the size of ..............

 

A. MCQ’s.

1. (b) Earth’s surface re-emits infra-red radiations after being heated by sunlight. These infra-red radiations are absorbed by green house gases present in atmosphere.

 

2. (b) By reducing cutting of forests & limiting the use of fossil fuels we

can control COz emission which is a major Green House Gas.

 

3. (d) Green House gases are CO2 CH,, CFC’s & Nitrous oxide.

 

4. (a) increased COz Concentration will lead to more heat absorbed & hence increased Green House effect.

 

5. (d) CO.CH, are two major Green House gases which absorb heat radiations.

 

 

B. TRUE/FALSE:

1. False . (Infra-red radiations are responsible for Green House effect)

2. True.

3. True.

 

C. FILL IN THE BLANKS:

1. Global warming.

2. Ozone Hole

 

PART: B SHORT ANSWER TYPE QUESTIONS:

1. What is Green House Effect?

2. What do you mean by Green House Gases?

3. What is Global warming?

 

PART: C LONG ANSWER TYPE QUESTIONS:

1. Discuss the effects of Global Warming?

 

A194

 

INTRODUCTION

Ozone layer is present in the stratosphere. It is also called ozonosphere. 90% of atmospheric ozone is present in ozonosphere.

Depletion in the concentration of ozone over a restricted area as over Antarctica is called ozone hole. There are many substances that react with ozone present in the stratosphere and destroy the same. Ozone

layer depletion causes many harmful effects on animals & environment.

 

OZONOSPHERE:Ozonosphere lies at altitude of 23-25 km over equators& slightly lower altitude elsewhere about 11-16 Km over poles. Thickness of ozone is measured in Dobson units. Concentration of ozone in the

ozonosphere is above 300 dobsons as compared to 50 dobsons in troposphere. In Stratosphere ozone is being formed & Photo dissociated. It

dissipates the energy of UV radiations.

 

Because of it ozonosphere functions as shield against strong UV radiations. Protection from UV radiations is proportional to thickness of

ozone layer.

 

OZONE HOLE:- Depletion in the concentration of ozone over a restricted area as over Antarctica is called ozone hole. An ozone hole was discovered over Antarctica. By Farman et al, 1985 who also coined the term. In the period 1997-2001, the global average ozone column has declined by 3 %.Thinning of ozone shield will increase the amount of UV-B radiation reaching the earth.

 

ODS:- (OZONE DESTRUCTING SUBSTANCES) They are the substances which read with ozone present in the stratosphere & destroy the same. The

major ODS are chlorofluorocarbons, nitrogen oxides, sulphur dioxide,halon, carbon tetrachloride, methyl chloroform, chlorine etc. Many of these are being released by jets flying in the stratosphere & rockets being fired into space. Others are persistent in the troposphere & gradually pass into

stratosphere. Maximum ozone depleting potential is of CFC due to release

of active chlorine (Cl, ClO) by it. Active chlorine gets perched over atmospheric ice crystals and remains functional for a long time.A single chlorine atom converts 1 lakh molecules of ozone into oxygen.Consequently CFC’s are being replaced by HYDROFLUORO- CARBONS & HYDROCHLOROFLUOROCARBONS. Carbon tetrachloride, halon & methyl chloroform also deplete ozone by a similar method. Nitric oxide (NO) & other gases released by jets directly react with ozone to form oxygen.

 

EFFECTS OF OZONE DEPLETION: UV radiations are of 3 types —UV-C, UV-B & UV-A . Shorter UV radiations UV-C are absorbed by the

atmosphere. The longer ones are not much harmful. The intermediate UV-B are harmful as well as capable of deep penetration. Thinning of ozone layer increases the amount of UV-B radiations reaching the earth. These radiations cause many harmful effects as follows.

|. Cornea absorbs UV-B radiations. It becomes inflamed the disorder is called, “Snow Blindness” or cataract. It loads to diminishing of eye sight, photo burning & later permanent damage to cornea.

 

ll. UV-B radiations damage skin cells cause ageing of skin & skin cancer.

 

lll. There is increased incidence of herpes & deficient functioning of immune system.

 

IV. Alarge no. of animals would become blind.

 

V. There will be higher mortality of young ones of animals.

 

VI. Damage to nucleic acids will increase resulting in higher number of mutations.

 

Vil. High energy UV radiations break chemical bonds of proteins & other biomolecules.

Vill. UV radiations inhibit photosynthesis

 

IX. Decreased photosynthetic activity will increase CO2 concentration of the atmosphere resulting in global warming.

 

X. Both marine & terrestrial food chains will be disturbed. World ozone day is celebrated on 16 September to spread awareness among people.

 

PART—~A VERY SHORT ANSWER TYPE QUESTIONS:

A. MULTIPLE CHOICE QUESTIONS:

1. Ozone layer occurs in:

A. Troposphere

B. Stratosphere

C.Mesosphere

D. Exosphere.

 

2. Thickness of ozone layer is measured in:

A. Dobson units

B. Decibel units

C. Pascal

D. Diopter.

 

3. Ozone hole is caused by:

A. Acetylene

B. Ethylene

C. Chlorofluorocarbons

D. Methane.

 

4. Result of ozone hole is:

A. Greenhouse effect

B. Global warming

C. Acid rain

D. UV radiations reach the earth.

 

5. World ozone day is celebrated on:

A. 16" Sept.

B. 21% April

C. 5 June

D. 22"? April.

 

B. TRUE/FALSE:

1. CH,is the main cause of ozone depletion.

2. Concentration of ozone is ozonosphere is above 300 Dobson's.

3. UV-radiations break chemical bonds of proteins.

 

C.FILLIN THE BLANKS:

1. The major ODS is  ...............cceese

2. Thinning of Ozone layer increases the amount Of ................000 reaching on the surface of earth.

 

ANSWER KEY: PART - A

(a) MCQs:

 

1. (b) Most of the ozone is present in Stratosphere.

 

2. (a) Thickness of ozone layer is measured in Dobson unit.

 

3. (c) CFC’s releases active chlorine which gets perched over ice crystals and remains functional for a long period. A single chlorine atom converts 1 lakh ozone molecules into oxygen.

 

4. (d) Thinning of ozone layer increases the amount of UV- radiations reaching on earth.

 

5. (a) On16™ September. World Ozone Day is celebrated.

 

(b) TRUE/FALSE:

1. False (CFC’s are the main cause of ozone depletion)

2. True.

3. True.

 

(c) FILL UPs:

1. Chlorofluorocarbons.

2. UV- radiations.

 

PART-B SHORT ANSWER QUESTIONS:

1. Name two ozone depleting substances.

2. How CFC’s deplete ozone layer?

3. What is Ozone Hole?

 

PART-C LONG ANSWER QUESTIONS:

1. Discuss the various harmful effects of ozone depletion


A195


United Nations Environment Program (UNEP) has been made to find solutions for ozone depletion and global warming.(16 September 1987) 27 industrialized countries


1.Montreal protocol: of chlorofluorocarbons to half the level of 1986.


2. May, 1989) Montreal protocol was ratified by 82 nations at Helsinki. They pledged to phase out CFCs by 2000.


3. In June 1990, 93 nations’ anended MONTREAL PROTOCOL and Helsinki Declaration. They agreed to phase out CFCs and other ODS by the end of 20th century.


4. Intergovernmental Panel on Climate Changes: (IPCC, 1988) prepared a world climatic program (WCP).


5. Convention on Climate Change: (CCC) Under UN framework in 1991.


6 .Earth summit: United Nations conference on Environment and Development, 1992).


i) It was held in Rio- de-janeiro (Brazil) and adopted recommendations of CCC for reducing greenhouse gases. The recommendations were signed by 154 nations.


ii) At Cancun in COP-16 an agreement was undertaken to limit global warming to below 2°c relative to preinpreindustrial level.


ii) In COP-18 at Doha a second commitment was undertaken to extend the Kyoto protocol for eight years from 2013-2020


iv) In COP-21(2015) held in Paris, it was agreed to limit the globz temperature increase to 1.5°C above the pre-industrial level.


7. Kyoto Protocol (Dec.1997) International conference held in Kyoto, Japan obtained commitments from different countries for reducing overall greenhouse gas emissions at a level 5% below 1990 level by 2008-2012( now

extended to 2020).


8.Beijing protocol (1999): The protocol lays down steps to reduce emissions of CFCs and other ozone depleting substances. It separates the efforts to be made by developing and developed countries.




LET US KNOW WHAT WE HAVE LEARNTH

A. MCQs:

i) Which association in 1987 agreed to limit production of chlorofluorocarbons to half the level of 1986?

a) Montreal protocol 

b) Helsinki protocol

c) Beijing protocol 

d) Kyoto protocol


ii) Convention on climate change was done in:

a) 1994 

b) 1991

c) 1998 

d) 1999


iii) Beijing protocol was laid down in:

a)1976 

b)1975

c)1997 

d)1901


iv) Japan obtained communities from different countries for reducing overall greenhouse gas emissions under:

a) Beijing protocol 

b) Earth summit

c) Montreal protocol  

d) Kyoto protocol


V) Helsinki declaration was done in:

a) 1989 

b) 1898

c) 1957 

d) 1972


B  FILLIN THE BLANKS:

i) UNEP is ---------—----- program.

ji) --------------- agreed to limit ozone depleting and global warming in 1987.


C TRUE/FALSE:

1. Beijing protocol in 1999 was laid down to reduce emissions of CFC's and other ozone depleting substances.

2. In COP-3 Kyoto protocol was negotiated

3. Earth protocol was held in Brazil in 1992 adopted the recommendation of CCC for reducing greenhouse gases.


ANSWER KEY: PART -A

A. MCQs:


i) (a)

ii) (b)

iii) (c)

iv) (d)

v) (a)


B. Fill IN THE BLANKS:

i) United Nations Environment Programme (made to find solutions for ozone depletion )


i) Montreal protocol ( to limit production of chlorofluorocarbons)


C. TRUE/FALSE:

i) True

ii) True

ii) True


PART: B SHORT ANSWER TYPE QUESTIONS:

i) Name the environment program which has done efforts to find solutions for pollution control?

ii) Describe earth summit?

iii) Write a few lines about Beijing protocol 1999?


i) Make a list of various efforts to find solution for ozone depletion and global warming made by UNEP and describe it.



A196


INTRODUCTION

DEFORESTATION:Deforestation is the removal, decrease or deterioration of forest cover of

an area.


1. Jhuming: It is slash and burn agriculture also known as shifting cultivation act, killing all plants and animals.


2. Hydroelectric projects: Dams, hydroelectric projects submerge forest

tracts killing all plants and animals.


3. EE. Huge forest fire engulfed areas in Indonesia in 1983 and 1997.


4) Human Establishments: To get more food and residential complexes more land is required.


5) Mountain and Forest Roads: Construction of roads and railways in hilly forests area brings a lot of Deforestation.


6) Overgrazing: Livestock grazing in forests causes compaction of soil.


7) Canals: Irrigation projects in 1974 in U.P. to irrigate land destroyed a million Sal trees and put land out of cultivation.


1) Shrinking Fuel wood: Deforestation reduces fuel wood.


2) Change in climate: Deforestation results in reduced rainfall.


3) Soil erosion: Soil is exposed, dries up and gets eroded by wind and water.


4) Siltation: Rainy season rivulets bring eroded soil and deposit the same on bed of reservoir.


5) Drought: There is very little water in rivers during dry season causes draught.


6) Global warming: Deforestation increases co2 content by releasing carbon stored in organic matter and reduced primary productivity.


7) Indigenous people: Tribal living in forests depends upon forests for their survival. Deforestation leads to their uprooting and loss of their livelihoods.


LET US KNOW WHAT WE HAVE LEARNT!

PART: A VERY SHORT ANSWER TYPE QUESTIONS:

A. MCQs:

1) When trees are cut and deterioration of forests take place. It is called

a) Deforestation 

b) Afforestation

c) Reforestation 

d) None


2) When forest fires engulf huge area  inIndonesia?

a) 1983 

b) 1987

c) 1985 

d) a&b


3) Which project was launched to irrigate 16 lakh hectare of land in U. P.?

a) Sarda sahayak canal 

b) Indira Gandhi canal

c) Both 

d) None


4) Deforestation increases due to:

a) Global warming 

b) Rainfall

c) Floods 

d) Soil fertility


5) Siltation means:

a) Rivers bring soil and deposit in reservoir

b) soil collected in rivers

c) Rivers get over flood with soil

d) None


(B) FILL IN THE BLANKS:

1) Cutting of trees is--—--.

2) Van Mahautsav being carried out inIndia since -------.


(C) TRUE/FALSE:

1) Afforestation is growing forest over an area where none existed earlier.


2) Urban forestry is to grow fruits, vegetables and shady trees in urban areas to reduce pollution.


3) Plantation of useful trees and shrubs for commercial requirements is commercial forestry.


ANSWER KEY: PART -A

A. MCQs:

1) (a) Deforestation (Cutting of trees)

2) (d)

3) (a)

4) (a) (increases CO, concentration)

5) (a)


B. FILL IN THE BLANKS:

1) Deforestation

2) 1970


C.TRUE/FALSE:

1) True

2) True

3) True


PART: B SHORT ANSWER TYPE QUESTIONS:

1) Define Deforestation and Afforestation.

2) What are various causes of Deforestation?

3) List the various effects caused by Deforestation.


PART:C LONG ANSWER TYPE QUESTIONS:

1) Define Deforestation? What are its causes and effects on population?


A197


INTRODUCTION

Ecological restoration is one of the most fundamental duties of each and every citizen in this world.


By saving the environment from pollution or other hazardous elements,can leads to sustainability, otherwise our future generations will curse us for not getting pure water, air and other natural products.

There are several communities in our country, who contributed a lot for the safety of our environment.



BISHNO!| MOVEMENT:

1. Bishnoi movement was started by Bishnois in 1731 in Rajasthan to stop the destruction of trees in Kherali village forest region.

Ee Wanted to build a new palace. He sent soldiers to cut the trees.


3. When king's men began to harm the trees, Bishnois protested.


4. AMRITA DEVI a female villager sacrifices her life and become inspiration for others.


5. 363 villagers gave their lives.


6. When king came to know about this activity, he stopped it and apologized.


7. Government of India declared Amrita Devi BISHNOI wildlife protection award for individuals and rural communities who show extraordinary courage and dedication in protecting wildlife.



CHIPKO MOVEMENT:

1. It is a movement initially meant for protecting trees but now for preservation of Environment, including habitat and wildlife.


2. It was born in 1973 in Chamoli district in Uttraknand.


3. Villagers escaped trees by hugging them thatis why this movement was known as CHIPKO movement.


LET US KNOW WHAT WE HAVE LEARNT!!


i) Name the award declared by government of India for individuals and communities who show extra courage for protection of wildlife?

a) Amrita Devi BISHNOI 

b) Gaura devi

c) Both 

d) None


ii) When was Chipko movement started?

a) 1978 

b) 1973

c) 1988 

d) 1986


iii)When did BISHNO! movement started?

a) 1931 

b) 1831

c) 1731 

d) 1631


iv) Appiko movement was started in:

a) North India 

b) South India

c) East India 

d) None


V) Name a valley saved through public agitation:

a) Silicon valley 

b) Silent valley

c) Kashmir valley 

d) None



i) ------------- movement was started in Rajasthan to save and conserve forests by community participation.

ii) Chipko movement started in----------- district in year-----------------.


¢) TRUE/FALSE:

i) Bishnoi movement was initiated to save and conserve trees.

ii) Appiko movement is not concerned with protection of trees.

iii) Government of India declared Amrita Devi Bishnoi award for conservation of trees in 1731.


A) MCQs:


i) (a) (Amrita Devi Bishnoi Wildfire Conservation Award)

ii) (b) (1973)

iii) (c) (1731)

iv) (b) (South India)

v) (b) (Silent valley in Kerala)


B) FILLIN THE BLANKS:

i)  Bishnoi

ii) Chamoli district, 1973

i) True

ii) False

iii) True.


i) When and where was CHIPKO movement started?

ii) Who was AMRITA Bishnoi? Why government of India declared award by het name?

iii) Name the movements initiated by individuals or communities for conservation of forests.


i) Describe the movements started by individuals or communities who played

important role in saving and conservation of trees and forests?


A198


INTRODUCTION

Joint Forest Management (JMF) is the official and popular term in India for partnerships in forest movement involving both the state forest departments and local communities.

Afforestation is GROWING FOREST over an area where none existed earlier.Van Mahotsava is being carried out in India since 1950. Both government and private agencies perform tree plantation during the months of February and July every year.


Reforestation is RESTORING A FOREST COVER over an area where one existed earlier but was removed at some time in the past.

As per recommendation of National Forest Commissions hills should have forest

cover 66% as compared to 33% for plains.

A higher and denser cover shall:-


(i) Increase percolation and absorption of rain water.

(ii) Prevent landslides.

(iii) Decrease runoff and hence flood.

(iv) Moderate climate


Joint Forest Management (JMF) is partnership involving both state forest departments and local communities in natural forest management. The concept was introduced by Government of India through the National

Forest Policy of 1988.


ORIGIN OF THEME:-

Accidentally originated in West Bengal at the Arabari forest range in 1971.


Was to prevent the unprotected grazing and illegal harvesting of major hardwood product (Sal).


Theme was introduced by AJITH KUMAR BANERGIEE (Divisional Forest Officer, Arabari fores t range). Under JFM, village communities are entrusted with the protection of management of nearby forests.


The communities are required to organize forest protection committees,village forest committees, village forest conservative and development societies, etc. Each of these bodies has an executive committee that

manages its day-to-day affairs.


In return of their services to the forests, the communities get the benefit of using minor non - timber forest produce. As a result, the forest can be conserved in sustainable manner. For example:-


Controlled grazing of cattle by the GADDI & GUJJAR tribes in the Himalayan states prevents the widespread growth of wild grass, thus contributing towards conservation of biodiversity.


BISHNOI] COMMUNITY of Rajasthan plays a very significant role in ecological joint conservation effort, with Joint conservation effort with the nomadic tribe of MALDHARIS, living in vicinity of Gir National Park, has contributed to the improvement of lion population.



The potential role of Joint Forest Management in improving the livelihood of the forest dwellers and fringe forest communities are as follows:


For working in coordination with villagers, Forest Committees are constituted which

play an active role to increase the agriculture and forest production and processing their produce. Employment opportunities, such as sustainable tourism are created in villages.


The Chipko movement or chipko andolan , was a forest conservation movement in India. The movement originated in 1973 at the Himalayan region of Uttarakhand However, it was Sunderlal Bahuguna, a Gandhian activist, and Chandi Prasad Bhatt, who gave the movement a proper direction and awareness to eco-groups by helping to slow down the rapid deforestation, increase social awareness and the need to save trees, increase ecological awareness. He used the slogan,


“Ecology is the permanent economy.”



The Panchayat (Extension to Scheduled Areas) Act, 1996 along with the Forest Rights Act plays a significant role towards ensuring entitlement to forest dwellers.


Aspecific woman sub-committee in the Joint Forest Management Committee (JFMC) ensures gender balance.


The JFMC provides training on animal husbandry, poultry farming, dairy

development and managing small forestry enterprises along with implementation of the National Rural Employment Guarantee programme in fringe forest areas.


Non-wood forest products (NWFP) are also important to JFM. NWFP are integral to lifestyle of forest-dependent communities. They fulfill basic requirements, provide gainful employment during lean periods and

supplement incomes from agriculture and wage labor. Medicinal plants collected through JFM have an important role in rural health.


MAJOR ASPECTS OF JFM:-Forest management is a branch of forestry concerned with overall

Administrative, Legal, economic and social aspects, as well as scientific and technical aspects,Such as silviculture, protection and forest regulation


CHALLENGES TO JFM:

The JFM program faces existential crisis.


On the one hand, legislations like the Forest Rights Act (FRA), 2006, and the

Panchayat Extension to Scheduled Areas (PESA) Act, 1996, have come into existence, giving rights to tribal and forest dwellers over forest resources and their management.


Communities demand the huge sums forest departments owe them under the program.


Questions are being raised whether the program should be scrapped.Implementation of JFM programs is expensive. The cost of afforestation,for example, is about Rs. 20,000 per ha.


Lack of legal status and financial and executive powers for FPCs.Forest Department in certain States vested with arbitrary powers to dissolve FPCs.


Faulty design of micro-plans and management plans.Absence of participation by women in spite of their formal representation in

management committees.


Unreasonable controls over the duration of exploitation of admitted resources

leading to low level of exploitation of admitted NTFPs.


Excessive rule and regulations.



Inadequate remuneration for local communities from JFM activities.


Inter and intra-community conflicts that hamper FPC functioning.


Denial of rights on disposal over valuable NTFPs to local communities.


FUNCTIONS OF JFM:

Micro-planning needs to ensure people participation in management of forest.


It should help to access the needs of the participating community and scope for development of the region or resource.


Itneeds to plan, project and regulate the benefit flow to the participant in

consultation with them.


It should identify and highlight the local resources and set priorities for resource development based on site conditions and available funds.


CURRENT STATUS OF JFM:After the initial success in West Bengal and Haryana, the JFM schemes received national importance in legislation of 1988. As per data of 2000, 27 states of the Indian Union had various JFM schemes with over 63000 FPCs

involved in this project over 1400,000 km? of forested land which was increased to 2460,000 by 2010 where 112896 committees with around 1450,000 families getting benefit from JFM program.


MAJOR RESEARCH FINDINGS:Apart from food subsistence collected from the local forests (including protected forest) to meet daily consumption needs of the forest-dwelling households, while as much as one-third (28.3%) of total per household

annual income is derived from sale of NTFPs.This precisely suggests success of protection and conservation measures

undertaken in the VSS assigned areas in the JFM study villages.


Further, while assessing the degree of dependence of the forest dwelling

population on forests (of the JFM sample villages) for their food subsistence

and livelihood, both the imputed value of consumption of NTFPs (by the forest dwelling households) and the sales value of NTFPs constitute as much as one half (49.0%).


Forestry activities are largely performed by female members, and as expected, while per household female person days of employment is 147 days compared to their male counterparts of 91 days, an average person secures only 80 days of employment per annum in forestry activities.


SUMMARY:Of late, the New Forest Policy (NFP) 1988 recognized that active

involvement and participation of communities in the management of local

forest resource is imperative for regeneration, protection, conservation and

development of degraded forests. Accordingly, in a major shift from the

traditional systems of forest management the JFM model emerged in many Indian States in 1990 (including Orissa) consistent with NFP 1988, and is now considered to be a revolutionary program in the forestry sector to make effective involvement of local communities in establishing sustainable Forest Management (SFM). Besides, it is now being looked upon as the only alternative to problems of deforestation and land degradation.


(A) MULTIPLE CHOICE TYPE QUESTIONS:


Q1. JFM in forest management stand for?

a) Junior forest management

b) Joint forest management

c) Both a) andb)

d) Neither a) nor b)


Q2. Bishnoi movement improved the count of decreasing:

a) Bear

b) Elephant

c) Tiger

d) Lion


Q3. Chipko movement was born in:

a) 1973

b) 1947

c) 2000

d) 2020


Q4. Chipko Movement was led by-

a) Sunder Lal Bahuguna

b) Chandi Prasad Bhatt

c) Both a) and b)

d) Neither a) nor b)


Q5.Where did the concept of joint forest management originate?

a) Andhra Pradesh

b) Haryana

c) Rajasthan

d) West Bengal


(B) TRUE / FALSE:

Q 1. JFMC ensures gender balance.

Q 2. JFMC does not provide employment.

Q 3. JFM provide empowerment to women.


(C) FILL UP THE BLANK SPACES:-

1) JFM was introduced by -----------—---.

2) Expand SFM---—-------—---—---—-.


a. MULTIPLE CHOICE TYPE QUESTIONS:

1. b)

2. d)

3. a)

4. c)

5. d)


b. TRUE/ FALSE:

1. TRUE

2. FALSE

3. TRUE


c. FILL IN THE BLANK SPACES:

1. Ajith Kumar Banergiee (Divisional Forest officer, Arabari forest range)

2. sustainable Forest Management


1) What is the role of women in JFM?

2) Give the various aspects of Joint Forest Management?

3) What do you meant by Jhum cultivation?


1) Write about the challenges facing Joint Forest Management Committee?




A199


INTRODUCTION

ENVIRONMENTAL ISSUES:Dear students we have taken all the topics of this chapter in detail.Now we shall go through some questions related to this chapter.

Environmental issues are issues related to human impact on the living environment, habitats, land use and natural resources. The following alphabetical list shows some of the main known environmental issues by

major topic title:


Climate change (encompasses "global warming”, greenhouse effect, loss of

glaciers, climate refugees, climate justice, equity, etc.)


Conservation (nature and animal  conservation, etc.)


Deforestation (illegal logging, impact of fires, rapid pace of destruction, etc.)


Desertification


Endangered species (loss of species, impact of chemical use on species,cultural use, species extinction, invasive species, etc.)


Energy (use, conservation, extraction of resources to create energy, efficient

use, renewable energy, etc.)


Environmental degradation

Environmental health (poor environmental quality causing poor health in human beings, bio-accumulation, poisoning)


Environmental impact assessment (one major current form of assessing human impact on the environment)


Food safety (including food justice, impacts of additives, etc.)


Genetically modified organisms and other forms of genetic engineering or modification


Global environmental issues (in recognition that environmental issues cross borders)


Global warming


Habitat loss (destruction, fragmentation, changed use)

 

Intensive farming and bio intensive farming

 

Invasive species (weeds, pests, feral animals, etc.)

 

Land degradation

 

Land use / Land use planning (includes urban sprawl)

 

Natural disasters (linked to climate change, desertification, deforestation, loss of natural resources such as wetlands, etc.)

 

Nuclear energy, waste and pollution

 

Ocean acidification (includes algal bloom, coral reef loss, etc.)

 

Over-exploitation of natural resources (plant and animal stocks, mineral

resources (mining), etc.)

 

Overfishing (depletion of ocean fish stocks)

 

Ozone depletion (CFCs, Montreal Protocol)

 

Pollution (air, water, land, toxins, light, point source and non-point source, use of coal/gas/etc., reclaimed land issues)

 

Population growth and related issues, like overpopulation, access to reproductive control (reproductive health), etc.

 

Reduce, reuse, repair and recycle (ways to reduce impact, minimize footprint, etc.)

 

Soil conservation (includes soil erosion, contamination and salination of land,

especially fertile land; see also desertification and deforestation)

 

Sustainability (finding ways to live more sustainably on the planet, lessening

human footprint, increasing human fulfillment with less impact) (see also

sustainable development and poverty alleviation)

 

Toxic chemicals (persistent organic pollutants, prior informed consent,

pesticides, endocrine disruptors, etc.)

 

Waste (landfills, recycling, incineration, various types of waste produced from

human endeavors, etc.)

 

Water pollution (fresh water and ocean pollution, Great Pacific Garbage Patch, river and lake pollution, riparian issues)

 

Water scarcity

 

QUESTIONS FROM NCERT TEXTBOOK :

 

1. What are the various constituents of domestic sewage? Discuss the effects of sewage discharge on a river.

Ans: Domestic sewage contains four kind of impurities:

(i) Suspended solids: They are soil particles such as sand and silt.

 

(ii) Colloidal particles: They are inorganic and organic materials such as

faecal matter, bacteria, paper and cloth

 

(iii) Dissolved solids: They are nitrates, phosphates, ammonia sodium,calcium and other nutrients.

 

(iv) Pathogens: Domestic sewage has pathogens of various disease such as

typhoid, cholera, dysentery, diarrhoea, etc.Effects of sewage discharge on river is:

(i) Eutrophication.

(ii) Growth of pathogenic bacteria.

(iii) Ageing of river where slit and decaying matters start accumulating and

filling river.

(iv) Increase in BOD

(v) Destruction of flora and fauna of that river.

 

2. List all the wastes that you generate at home, school or during your trips to other places. Could you very easily reduce the generation of these wastes? Which would be difficult or rather impossible to reduce?

Ans: Waste materials generated at home: paper, disposable cups, cloth,plates, spoons, plastic envelopes, discarded food etc. Wastes materials generated during trips are: paper, disposable cups, plates, spoons, plastic envelopes, discarded food etc. No, we cannot reduce the generation of these wastes easily, but few can be

reduced. The wastes belong to two categories: biodegradable and non-

biodegradable. It is difficult or rather impossible to reduce discarded food

like peel of potato, peel of banana etc. We can do one important thing i.e., to

reduce wastage of food.

 

3. Discuss the causes and effects of global warming. What measures need to be taken to control global warming?

Ans: Causes of global warming:

|. Increase in concentration of greenhouse gases.

Il. Increase of automobile and use of fossil fuel.

Ill. Deforestation and change in land use

IV. CFC and aerosol emission from refrigerator and aero plane.

V. Increased particulate matter in lower atmosphere.

 

Effects of global warming:Many species of plants, being sensitive to temperature will die with sudden rise in temperature. Loss of biodiversity. Rise in sea level.

Possibilities of drought and floods. Change in rainfall pattern.Methods that can reduce the atmospheric concentration of greenhouse gases are:Reducing the greenhouse gas emission by limiting the use of fossil fuels,by developing alternate renewable sources of energy( wind energy, solar energy) Increasing vegetation cover, Minimizing the use of nitrogen fertilizers in agriculture. Developing substitutes of chlorofluorocarbons.

 

4. Write critical notes on the following:

(a) Eutrophication

(b) Biomagnification

(c) Groundwater depletion and ways for its replenishment

Ans: (a) Eutrophication: It is excessive growth of algae, plants and animals

in water-bodies due to nutrient enrichment particularly with nitrogen and phosphorus. It is both natural and accelerated. It leads to loss of biodiversity and causes chemical accumulation in food chain and ageing of water bodies.

 

b) Biological magnification: Increase in concentration of persistent chemical

at successive trophic levels is called eutrophication. This happens because a

toxic substance accumulated by an organism cannot be metabolized or excreted, and is thus passed onto next trophic level, e.g., DDT.

 

(c)Ground water depletion and replacement: Ground water depletion, a term often defined as long term water level declines caused by sustained ground water pumping, is a key issue associated with ground water use.Many areas of India experiencing ground water depletion.The most severe consequence of excessive ground water pumping is that the water table, below which the ground is saturated — with water, can be lowered. If ground water level declines too far, then the well owner might have to deepen the well, drill a new well, or at least attempt to lower the pump.

 

5.Why ozone hole forms over Antarctica? How will enhanced ultraviolet radiation affect us?

Ans: Chlorofluorocarbons, mainly released in the atmosphere by developed countries, slowly enters the stratosphere and the winds move them towards the poles. Environmental conditions prevailing in Antarctica during winter months; there is no sunlight in Antarctica and extremely low temperature (— 85°C) facilitates the formation of ice clouds. During winter,

natural circulation of wind (polar vertex) completely isolates Antarctic air

from the rest of the world. The ice clouds provide the catalytic surface for

the reaction of chlorine atoms and then ozone. But this degradation of ozone occurs with the return of solar radiations to Antarctica during spring (September and October). This results in the thinning of ozone layer every year over most of Antarctica. This hole disappears in summer

due to warming up of air and the mixing up of Antarctic air with that of the

rest of the world.Enhanced UV radiations on earth would affect humans and

other animals by causing:

 

Skin cancer.

 

Blindness and increased chances of cataract in eyes.

 

Malfunctioning of immune system.

 

Higher number of mutations.

 

6. Discuss the role of women and communities in protection and conservation of forests.

Ans: Amrita Bishnoi Wildlife protection project The Bishnoi community is known for

its peaceful coexistence with nature. It was in 1730 AD. Amrita Devi protested

against king's men’s attempt to cut trees as it was prohibited in Bishnoi religion. It was a party of Maharaja Abhay Singh ji, ruler of Marwar (Jodhpur) wanted to fell green Khejdali trees. Amrita Devi with her three daughters and more than 360 of other Bishnois lost their lives in saving trees and became martyrs. Later Chipko movement was started by Sunder Lal Bahuguna and

others to prevent cutting trees. The people showed enormous bravery in

protecting trees from the axe of contractors by hugging them.

 

7. What measures, as an individual, would you take to reduce environment Pollution?

Ans: To reduce environmental pollution we should take following measures:

Reducing use of CFC.

Disposing off waste safely.

Reducing use of polythene.

Not disposing off waste in water bodies.

Making automobiles pollution free.

Prevention of noise pollution by using fire crackers/TV/musical instruments at

permissible limits.

Tree plantation in school, around residence.

 

8. Discuss briefly the following:

(a) Radioactive wastes

(b) Defunct ships and e-wastes

(c) Municipal solid wastes

Ans: (a) Radioactive waste: Radioactive waste includes materials that are

radioactive & for which there is no further practical use. These are generated by nuclear reactor, nuclear fallout, manmade (refining and mining of platinum and thorium), natural radioactive waste and release of radiation in radiation therapy.Increased risk of cancer, birth defects & infertility are few harmful

effects caused by nuclear waste. So, nuclear waste is an extremely potent

pollutant.

 

(b) Defunct ships & e-wastes — The dismantling of defunct ship is a technically complex process, which is potentially harmful to the environment & human health. Defunct i ships contain toxicants like asbestos, mercury, etc. The

workers breaking the ships are not suitably protected and are exposed to toxic chemicals.The coastal areas in the vicinity of the ship- breaking yard also become polluted. At the international level, it is accepted that there is uncertainty about the relevant controls for the dismantling of such vessels & there is an urgent need to establish a specific enforceable control framework.

Electronic waste comprised of irreparable computer and other electronic goods, generated by developed countries. It is valuable source of secondary raw materials, if treated properly, however if not treated properly it is the major source of toxins. Eventually recycling is

the only solution for the treatment of e-wastes provided it is carried out in an environment friendly manner.

 

9. What initiatives were taken for reducing vehicular air pollution

in Delhi? Has air quality improved in Delhi?

Ans:The initiatives were taken for reducing vehicular air pollution in Delhi

are:-

(i) Introduction of CNG

(ii)Enforcement of pollution control law

(iii) Introduction of green zones

(iv) Use of unleaded fuels

(v)Replacement of old vehicle with new one. The result is that the air quality of

Delhi has improved considerably with a substantial fall in pollutant gases.

(vi) Use of catalytic converters in vehicles.

(vii)Application of Euro Il norms for vehicle.

 

10. Discuss briefly the following:

(a) Greenhouse gases

(b) Catalytic converter

(c) Ultraviolet B

Ans:(a) Greenhouse gases:Gases that trap the heat of the sun in the earth's atmosphere increasing atmospheric temperature effect are called greenhouses gases. COQ2, CHa,N2O and CFC, cause greenhouse. In the absence of greenhouse gases,the temperature of earth would go down to - 18°C. The net effect of higher

GHGs will be disastrous, melting of polar ice caps and mountain snow caps resulting in rising of sea level threatening submergence of many islands and coastal areas.Odd climate changes like increased floods and drought.

 

(b) Catalytic converter:Catalytic converter ‘are used to reduce emission of poisonous gases like nitrogen oxides, carbon monoxide & un reacted hydrocarbon in automotive emission. It is made of platinum, palladium and rhodium and is used as catalyst. It converts unburnt hydrocarbons into COz. The only precaution

required is not to use gasoline having lead as lead inactivates the catalysts

of the converter.

 

(c) Ultraviolet B:Ultraviolet B is one of the three types of invisible light rays given off by the sun. Ultraviolet B penetrates the ozone layer in attenuated form & reaches earths. This is more over equator than poles due to thinning of ozone shield over equator. It causes skin cancer, reduce rate of photosynthesis in

phytoplankton, and reduces diversity of aquatic ecosystem.

 


A200

 

INTRODUCTION

ENVIRONMENTAL ISSUES:Environmental issues are harmful effects caused to environment because of human activities. It causes degradation in the quality of air, water and soil. These unfavorable events cause environmental issues that affect the natural state of the environment.

 

ENVIRONMENTAL POLLUTION:Pollution is an undesirable change caused to the chemical, biological, and physical composition of air, soil and water. The wastes that cause pollution are called pollutants.

The various pollution types include air, water, noise, soil and radioactive

pollution.

 

GLOBAL WARMING:Global warming is the gradual increase in the temperature of the Earth. It happens when there is an increase in the level of greenhouse gases in the atmosphere. The greenhouse gases present in the atmosphere prevent heat captured from the sun from escaping to the outer space. These gases are thus, responsible for keeping the Earth warm. With the rise in the level of greenhouse gases, the Earth’s temperature also rises. This is an environmental concern that can cause problems to nature and, eventually, to humans.Global warming is caused because of industrialization, deforestation, vehicle emission, and farming in factories.

 

Global warming can be controlled by Cutting down use of fossil fuel, Improving

efficiency of energy usage, reducing deforestation, planting trees, slowing down the growth of human population.

 

OZONE DEPLETION IN THE STRATOSPHERE:

Ozone found in the upper part of the atmosphere called stratosphere acts as a

shield, absorbing ultraviolet radiations from the sun. UV rays are highly injurious

to living organisms

 

SOLID WASTE:



Solid waste comes from offices, homes, hospitals and schools that are disposed of by the town municipality. These comprise solid wastes like plastics, paper, glass,leather, and many more such things. Solid waste is either dumped or burnt in the sanitary landfill.

 


DEPLETION OF NATURAL RESOURCES:When the natural resources get depleted, then this too causes environmental pollution. The consumption of fossil fuels leads to the emission of greenhouse gas.This again causes a change in the climate and leads to global warming.

 

ELECTRONIC WASTES:



Electronic wastes are basically electronic goods like computers that are unrepaired. These are called e-wastes, which are either buried in the landfills, or they are incinerated. The e-wastes that are generated in the developed countries are sent to the developing nations to recover metals like iron, copper, gold, nickel etc. Recycling is the only way to treat the e-wastes.

 

AGRO — CHEMICALS:Inorganic pesticides and fertilizers have seen a massive increase in use because of the green revolution. This helps to enhance the production of

crops. The insecticides and pesticides are toxic.



These get biomagnified in the terrestrial ecosystem that causes eutrophication in the ecosystem of aquatic life.

 

DEFORESTATION:Another major environmental concern is deforestation. This happens because of the destruction of trees that are used to make buildings. Trees are also cut for obtaining raw materials. Deforestation causes global warming, soil erosion and also leads to extinction in biodiversity. Main consequences of deforestation includes-Enhanced carbon dioxide concentration, Loss of biodiversity, Disturbed hydrologic cycles, Soil erosion and Desertification etc.

 

AIR POLLUTION:Air is essential for respiration in all living organisms. Pollutants reduce growth and production of crops as well as premature death of plants. The harmful effect of pollution on all the living organisms depends upon-Concentration of pollutants and

Duration of exposure. Thermal power plants, smelters and other industries release particulate and gaseous air pollutants. These pollutants should be filtered out before releasing the harmless gases into the atmosphere. There are many

methods of removing particulate matter. The most widely used is the Electrostatic

Precipitator that can remove over 99% of particulate matter present in the exhaust

from thermal power plant.

 


A Scrubber can also remove gases like sulphurdioxide. The exhaust is passed

through spray of water or lime.

 

NOISE also causes sleeplessness, increased heart beating, altered breathing

pattern, thus considerably stressing humans. Reduction of noise in industries can be affected by use of sound absorbent materials or by muffling noise.

 

WATER POLLUTION AND ITS CONTROL: Water bodies are lifeline of human beings as well as other animals. Due to disposal of all kinds of waste and other anthropogenic actions the ponds, lakes, stream, river, estuaries and oceans 



are becoming polluted in several parts of world. The Government of India has passed the Water (Prevention and Control of Pollution) Act, 1974 to protect the water resources.

 

DOMESTIC SEWAGE AND INDUSTRIAL EFFLUENTS:The sewage that comes out from house and office makes the domestic sewage. A mere 0.1% impurities make domestic sewage unfit for human use. Solid wastes are relatively easy to remove but dissolved salts as nitrates, phosphates and other nutrients and toxic metal ions and organic compounds present in domestic wastes are comparatively difficult to remove. Domestic sewage mainly contains

biodegradable organic matter, which can be easily decomposed by microbes like

bacteria and fungi. They use organic wastes as nutrients.

 

BIOLOGICAL OXYGEN DEMAND (BOD):The microbes that decompose organic wastes in water bodies consume a lot of oxygen that result into sharp decline in dissolved oxygen downstream from the point of sewage discharge. This causes mortality of fish and other aquatic creatures. BOD refers to the amount of oxygen that would be consumed if all the organic matter is one liter of water were oxidized by bacteria. The BOD test measures the rate of uptake of oxygen by micro- organisms in a sample of water.Indirectly BOD is a measure of the organic matter present in the water. Thegreater the BOD of waste water more is its polluting potential.

 


ALGAL BLOOM is presence of large amount of organic nutrients in water causes excessive growth of planktonic or free floating algae called algal bloom.Due to this color of water bodies get changed. This may cause deterioration of the

water quality thus increase in fish mortality. Water hyacinth (Eichhornia) is the world’s most problematic aquatic weed. They were introduced into India for their

beautiful flowers that have caused havoc by their excessive growth by causing

blocks in our water bodies. This weed is commonly known as ‘Terror of Bengal’.

 

BIO MAGNIFICATION or BIOLOGICAL MAGNIFICATION: Toxic wastes present in industrial wastes and water from farmhouse containing pesticides and weedicides enters the food chain of aquatic  organisms. This increase in concentration

of toxicant at each successive trophic level is called biological magnification.

 The most common toxicant that gets accumulated at successive trophic levels includes DDT and Mercury. High concentrations of DDT disturb calcium metabolism in birds,which causes thinning of eggshell and their premature breaking, eventually causing decline in bird populations.

 


EUTROPHICATION It is the natural aging of a lake by biological enrichment of

its water. Due to addition of nutrients such as nitrogen and phosphorus that

encourage the growth of aquatic organism the accumulation of organic remains in

course of time leads to shallowing of lake. Over the centuries the silt and organic debris piles up at the bottom of lake and encourage the growth of marsh plants.Eventually large masses of floating plants grows and finally converting into land.The pollutants from man’s activities such as effluents from the industries and

homes radically accelerate the aging of lake. This phenomenon is called Cultural

or Accelerated Eutrophication. Main contaminants include nitrates, phosphates

that act as plant nutrients. They increase the growth of algae, causing unsightly

scum and unpleasant odors, and depleting the dissolved oxygen of water which

is important for other aquatic life.

 

INTEGRATED WASTE WATER TREATMENT Wastewater including sewage can be treated in an integrated way, by combining artificial and natural processes. The Government of India has recently started the Amrita Devi Bishnoi Wildlife Protection Award for individuals or communities from rural areas that have shown extraordinary courage and dedication in protecting wildlife.

 

CHIPKO MOVEMENT - In 1974, local women of Garhwali Himalayas showed tremendous courage in protecting trees from the axe of contractors by hugging them. Realizing the importance of participation by local communities, the Government of India in 1980s has introduced the concept of;

 

The biologists developed a series of six connected marshes over 60 hectares of marshland where plants, algae, fungi and

bacteria were seeded which neutralize, absorb and assimilate the pollutants. As

the water flows through the marshes, it gets purified naturally. The marshes also

constitute a sanctuary, which is highly diverse in the form of fishes, animals and

birds that now reside there. Ecological sanitation is a sustainable system for

managing human excreta, using dry composting toilets. Human excreta can be

recycled into natural fertilizer. There are working ‘Eco San’ toilets in many areas of Kerala and Sri Lanka.

 

SUMMARY:With increase in human population, demands for food, shelter, water,

electricity, Roads and automobiles are increasing rapidly and exerting

pressure on Environment and altering the natural health of ecosystem. All

across the world, People are facing a wealth of new and challenging

environmental problems every day. Some of them are pollution,greenhouse effect, ozone depletion, deforestation etc. Pollution is undesirable change in physical, chemical or biological properties of air,land, water or soil.

 

The agents which cause undesirable change are called pollutants.Loss in biodiversity, depletion of the ozone layer, effects on marine life and

increase in the carbon footprint are other factors that cause Environmental Issue

 

ENVIRONMENTAL ISSUES SOLUTIONS:Following are the solutions to environmental issues: Recycling of waste

Conservation of water and electricity

 

Use reusable items instead of disposable items

 

Avoid using plastics

 

Minimize the use of vehicles

 

LET US NOW ASK YOU SOME QUESTIONS!!

(A) MULTIPLE CHOICE TYPE QUESTIONS:

 

Q1. The natural aging of lake is called:

a) Bio magnification

b) Eutrophication

c) BOD

d) None of these

 

Q2. The agents that bring undesirable changes in the environment are called:

a) Pollution

b) Fragments.

c) Pollutants

d) None of the above

 

Q3.Which metal activates a catalytic converter?

a) Gold

b) Iron

c) Silver

d) Lead

 

Q4. E-Waste is referred to as:

a) Radioactive Waste

b) Nuclear waste

c) Both (a) and (b)

d) Electronic Waste

 

Q5.increased skin cancer and high mutation rate are due to:

a) Acid rain

b) Ozone depletion

c) Algal bloom

d) CO pollution

 

B. TRUE/FALSE:

1. The particulate matter can be removed by convertor.

2. Ozone layer is found in Stratosphere.

3. Use reusable items instead of disposable items

 

C. FILL UPS:

1. is undesirable high level of sound.

2.The natural aging of a lake is called .

 

ANSWER KEY: PART-A

A) MULTIPLE CHOICE TYPE QUESTIONS:

Q1. (b) Eutrophication

Q2. (c) Pollutants

Q3. (d) Lead

Q4. (d) Electronic Waste

Q5. (b) Ozone depletion

 

B) TRUE/FALSE:

1. FALSE

2. TRUE

3. TRUE

 

C) FILL UPS:

1. Noise

2. Eutrophication

 

1. Why is a scrubber used? Which spray is used on exhaust gases passing through a scrubber?

2. Precipitator can remove over  99%particculate matter present in exhaust

from a thermal power plant. How?

3. What is relationship between BOD, micro-organisms and amount of Biodegradable matter?

 

1. (a) Discuss the role of women and communities in protection and conservation of forests.

(b) Explain Bio magnification of DDT in an aquatic food chain. How does it affect the bird population?

 


Chapter 16 Environmental Issues