UNIT 4
Disaster Management, Social Issues, Human Population And The Environment
A) Disaster Management
Disaster is a sudden calamity which brings misfortune and miseries to humanity.
Types:
1. Natural disaster
2. Man-made disaster
Natural disaster: Floods, Cyclones, earth quakes, landslides. Etc
Man-made disaster: Accidents, pollutions, fire accidents, bomb blasts.
FLOODS:
Defined as a situation when the river over flows is banks and the water spreads in the surrounding areas and submerging them. It usually occurs in rainy season.
Causes
- Heavy intense rain fall
- Melting of accumulated snow
- Melting of snow combine with rains
- Over saturated soil when the ground cannot hold any more water
- Urbanization
Control
- Forecast, warning and advice should be provided through media to educate aware people about steps to be taken on the event of mishap.
- Valuable house hold items, animals and materials like food, clothes, medicines etc. should be shifted to safe places.
- Elderly people and children should be evacuated to safer place on emergency.
- By the construction of protective works.
EARTHQUAKE:
Sudden vibration caused on the earth surface due to sudden release of tremendous amount of energy stored in the rocks under the earth crust is called earthquake.
A focus of an earthquake is the point of initial movement. Epicenter is the point on the surface directly above the focus.
Measure of Earth quake-Richter scale
Magnitude of earthquake is a measure of amount of energy released in the earthquake. Earthquake is recorded by seismograph.
- Less than 4-insignificant
- 4-4.9-minor
- 5-5.9-damaging
- 6-6.9-destructive,
- 7-7.9-major
- Above 8- great
- Primary effect of earth quake: Shaking
Sometimes a permanent vertical or horizontal displacement of the ground .This affects people bridges, dams, pipe lines.
Secondary effects
Rocks slides, flood caused by the subsidence of land, coastal areas are severely damaged .Earth quake generated water wave called Tsunami and also called tidal waves that travel as fast as 950km/hr.
Precautionary measures
- People should come out of their homes and stay in the open till the tremors subside.
- People already out of home should stay away from the building electric poles, trees and any tall objects that have chances of falling down.
- After the earth quake relief camp by the Government or other social groups should be conducted for the affected people.
CYCLONE:
An atmospheric closed circulation, rotating anti- clock wise in the northern hemi sphere and clock wise in southern hemisphere .
Cyclone is an area of low pressure in the centre and high pressure outside. Powerful swirling storm that measures from 300- 500 km in diameter. The wind in the centre of cyclone blows in the speed of 120km/hr.
In India cyclone originates from Bay of Bengal are more in number and intensity. Relatively less south-west Indian Ocean and Arabian Sea. In India cyclones occur during October-December or April-May.
EFFECTS
- Damage to human life, crops, roads, transport, and communication could be heavy.
- Cyclone slows down developmental activities of the area.
Management
- Meteorological Departments forecast by satellite images the weather conditions which reveal the strength and intensity of the storm.
- Radar systems is used to detect cyclone and cyclone warning.
- The effect of cyclone is minimized by planting more trees on the coastal belts, constructional dams, wind breaks etc.
LAND SLIDES :
A landslide is a sudden collapse of large mass of hill side.
Types
- Shallow disrupted land slide
- Decoherent landslide
Factors causing landslides
- Caused by rain forces increasing top material weight, lubricating the material layer or making slope top steep.
- Gravity-gravity works more effectively on steeper slopes
- Weather: Most slides occur during or after heavy rains
Effects
- Flow deposit blocks the road and diverts the passage
Prevention
- Revegetate the area to prevent the surface erosion .Inspect and repair all drainage system. Collect runoff from roofs and improved areas and convey water from the steep slopes in a well designed pipe system.
Nuclear accidents and holocaust
A nuclear and radiation accident is defined by the International Atomic Energy Agency as "an event that has led to significant consequences to people, the environment or the facility. Examples include lethal effects to individuals, large radioactivity release to the environment, or reactor core melt." The prime example of a "major nuclear accident" is one in which a reactor core is damaged and large amounts of radiation are released, such as in the Chernobyl Disaster in 1986.
The impact of nuclear accidents has been a topic of debate practically since the first nuclear reactors were constructed. It has also been a key factor in public concern about nuclear facilities. Some technical measures to reduce the risk of accidents or to minimize the amount of radioactivity released to the environment have been adopted. Despite the use of such measures, "there have been many accidents with varying impacts as well near misses and incidents.
The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions. Since part of this re-radiation is back towards the surface, energy is transferred to the surface and the lower atmosphere. As a result, the average surface temperature is higher than it would be if direct heating by solar radiation were the only warming mechanism.
Solar radiation at the high frequencies of visible light passes through the atmosphere to warm the planetary surface, which then emits this energy at the lower frequencies of infrared thermal radiation. Infrared radiation is absorbed by greenhouse gases, which in turn re-radiate much of the energy to the surface and lower atmosphere. The mechanism is named after the effect of solar radiation passing through glass and warming a greenhouse, but the way it retains heat is fundamentally different as a greenhouse works by reducing airflow, isolating the warm air inside the structure so that heat is not lost by convection.
The existence of the greenhouse effect was argued for by Joseph Fourier in 1824. The argument and the evidence was further strengthened by Claude Pouillet in 1827 and 1838, and definitively proved experimentally by John Tyndall in 1859, and more fully quantified by Svante Arrhenius in 1896.
If an ideal thermally conductive blackbody was the same distance from the Sun as the Earth is, it would have a temperature of about 5.3°C. However, since the Earth reflects about 30% (or 28%) of the incoming sunlight, the planet's effective temperature (the temperature of a blackbody that would emit the same amount of radiation) is about −18 or −19°C, about 33°C below the actual surface temperature of about 14°C or 15°C. The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect. Earth’s natural greenhouse effect makes life as we know it possible. However, human activities, primarily the burning of fossil fuels and clearing of forests, have greatly intensified the natural greenhouse effect, causing global warming.
B) Social Issues, Human Population and the Environment
Global warming
Global warming is a Global phenomenon. It refers to a gradual increase in the temperature of the Earth due to trapping of green house gases. A gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels carbon dioxide, CFCs, and other pollutants. Warming of the climate system is unequivocal, and scientists are 95-100% certain that it is primarily caused by increasing concentrations of greenhouse gases produced by human activities such as the burning of fossil fuels and deforestation. Gases such as CO2, SO2, NO2,CH4, etc. Are the green house gases. Most of these are the polluting gases that are produced by the industries. These gases trap the heat from the sunrays that are reflected from the sun.
Causes of Global Warming
It is the effect of the process of trapping of Heat due to CO2 which has been going on since times unknown. As we burn fossil fuels like coal, oil and natural gas for energy or cut down and burn forests to create pastures and plantations, carbon accumulates and overloads our atmosphere. Certain waste management and agricultural practices aggravate the problem by releasing other potent global warming gases, such as methane and nitrous oxide.
The major greenhouse gases are water vapour, which causes about 36–70% of the greenhouse effect; carbon dioxide (CO2), which causes 9–26%; methane (CH4), which causes 4–9%;and ozone (O3), which causes 3-7%. Clouds also affect the radiation balance.
Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radioactive forcing from CO2, methane, troposphere ozone, CFCs and nitrous oxide.
Effects of global warming
- Sea level rise is accelerating. The planet's temperature is rising.
- Dangerous heat waves are becoming more common.The number of large wildfires is growing.
- Extreme storm events are increasing in many areas. More severe droughts are occurring in others. These are having significant and harmful effects on our health, our environment, and our communities.
Prevention Of Global Warming
The various ways to control Global Warming are:-
- Control of population. But, since it is not possible to control population, the best way to control Global warming is by planting trees - Decrease deforestation/plant forests
- Produce more fuel-efficient vehicles
- Use of ecofriendly and biodegradable products.
- Improve energy-efficiency in buildings
- Develop carbon capture and storage processes
Acid rain
ACID RAIN is a rain or any other form of precipitation that is usually acidic i.e. it has low pH. Acid rain is caused by emissions of sulphur dioxide and nitrogen oxide, which react with water molecules in the atmosphere to produce acids.
Involves deposition of aqueous acids, acidic gases and acidic salts. Acid deposition has 2 parts: wet and dry - Wet deposition refers to acidic rain, fog & snow - Dry deposition refers to acidic gases and particles - Half of the acidity in the atmosphere falls back to earth through dry deposition.
Sources
Acid rain comes from chemical reactions in the atmosphere among oxygen, water and sulfur or nitrogen oxides. When sulfur dioxide dissolves in small droplets of water in clouds, it reacts with the hydrogen and oxygen of the water to form a weak solution of sulfuric acid. Similarly, nitrogen oxides form weak nitric acid in water droplets. The clouds can drift over hundreds of miles carrying their acid droplets. When conditions are right for rain, the droplets grow and fall to the ground. In many areas of the United States, such as the great plains, the acid rain falls mostly on land used for agriculture.
Causes of Acid Rain
The primary cause of acid rain is the emission of harmful gases and emissions by industrial power plants and factories, and to some extent, cars as well.
Burning of fossil fuels lead to emission of gases that give oxides of sulphur and nitrogen.
Burning of gasoline and diesel in cars build the amount of acidified water droplets in the atmosphere.
Effects of Acid Rain
The effects of acid rain are unhealthy and harmful. Buildings, national monuments and bridges tend to deteriorate faster.
Acid rain has been found to be very hard on trees. It weakens them by washing away the protective film on leaves, and it stunts growth.
The biggest reason to find satisfactory solutions for acid rains is the damage to natural ecosystems. This rain will affect the plants, trees, rivers, lakes, soil and land wherever it may fall on.
Animals and plants that live in such areas are severely affected. Their food sources get diminished, they may develop unhealthy diseases or mutations, or they may even die in extreme cases,
EFFECT ON HUMANS
The pollutants that cause acid rain—sulphur dioxide and nitrogen oxides damage human health. These gases interact in the atmosphere to form fine sulphate and nitrate particles that can be transported long distances by winds and inhaled deep into people's lungs. When we breathe in air pollution, these very fine particulates can easily enter our body, where they can cause breathing problems (asthma), bronchitis and over time even cause skin cancer.
Solutions for acid rain
To solve the acid rain problem, people need to understand how acid rain damages the environment. They also need to understand what changes could be made to the air pollution sources that cause the problem. Use Low Sulphur Coal The amount of sulphur oxides emitted by a power plant can be reduced by burning coal with a very low percentage of sulphur present.
Ozone layer depletion
The ozone layer in the upper atmosphere absorbs the sun’s ultraviolet radiation, preventing it from reaching the earth’s surface. This layer in the atmosphere protects life on earth from the dangerous UV radiation from the sun. The chemicals called chlorofluorocarbons or CFCs, which were used as refrigerants and aerosol spray propellants, posed a threat to the ozone layer.
The destruction of the ozone layer is seen to cause increased cases of skin cancer and cataracts. It also causes damage to certain crops and to plankton, thus affecting natures food chains and food webs. This in turn causes an increase in carbon dioxide due to the decrease in vegetation. Protecting the Ozone Layer Ban the use of CFC’s Have to replace with something Current replacements are greenhouse gases and do not eliminate ozone depletion, just slow it down.
Waste water reclamation
Reclaiming lands that have been laid waste in an extraction or industrial process is "wasteland reclamation." Strip-mining coal produces wastelands. Using chemicals in an industrial process, then dumping the used chemicals either on the land or into a stream creates wastelands or releasing chemicals into the air in an industrial process can create waste lands. When there is no regulation of wastes disposal by the industry can create wastelands. And finally, nuclear accidents can create wastelands.
Environment keeps changing over time naturally and it is also amenable to changes by human beings. Thanks to scientific and technological developments, our ability to alter the environment has increased tremendously, whereas the capacity of environment to cope with those alterations is limited. Nature's bounty and abundance are disappearing at a rapid rate now in many regions of the world including India due to the human alterations of the environment. All this has brought to the fore the need for protection and preservation of environment and the urgency of developing sound environmental policies and programmes. Without them, development would not only be unsustainable but would be tantamount to retrogression. The challenge of creating and maintaining a sustainable environment is probably the single most pressing issue confronting us today and will remain so in the foreseeable future.
The Department of Land Resources, Ministry of Rural Development and Government of India has identified different types of degraded wastelands and has prepared a Wasteland Atlas of India for the year 2000, with the help of Indian Remote Sensing Satellites. According to their estimates, the degraded wastelands accounted for about 20.16 % of India’s total geographical area. The degraded lands include several types of land such as gullied and /or ravinous land, water-logged and marshy land, land affected by salinity and / or alkalinity, degraded pastures / grazing land, degraded notified forest land, mining industrial wastelands, eroded steep slopping land, sandy and desertic lands, and barren rocky /stony wastelands. Whatever the type of degradation, a common characteristic of degraded lands is that their productivity is almost negligible but it could be restored through proper reclamation measures and management.
It is estimated that in India in 1994, about 188 million ha of land, which is 57 per cent of the country’s total geographical area of about 329 million ha, was degraded. Of the 188 million ha of degraded land, about 149 million ha was affected by water erosion, 13.5 million ha by wind erosion, about 14 million ha by chemical deterioration and 11.6 million ha by water-logging (Sehgal and Abrol, 1994). A recent survey by the National Bureau of Soil Survey and Land Use Planning revealed that 66 per cent of India’s total geographical area (around 192 m ha) was at varying stages of degradation (quoted in Haque, 1997).
Land degradation has significant adverse impacts on crop productivity and the environment. Joshi and Jha (1991) in a study of four villages in Uttar Pradesh found that a 50 per cent decline in crop yields over a period of eight years was due to salinity and water -logging caused by the irrigation system.
Consumerism and waste products
- Consumerism is related to the constant purchasing of new goods, with little attention to their true need, durability, product origin, or the environmental consequences of their manufacture and disposal.
- Consumerism interferes with the sustainable use of resources in a society by replacing the normal common sense desire for an adequate supply of life’s necessities, with and insatiable quest for things that are purchased by larger and larger incomes to buy them.
- Especially in developed countries, landfills are being rapidly filled with cheap discarded products that fail to work within short time and cannot be repaired.
- In many cases, consumer products are made psychologically obsolete by advertising industry long before they actually wear out.
- The inordinate amount of waste that is generated by consumer-oriented societies around the world is now a serious environmental issue.
- Most human activities are related to production and consumption cycle which produce excessive amounts of waste in the form of solid, liquid and gaseous waste products.
- With the advent of and industrial civilization, the highly complex technological processes for production of goods have rapidly increased problems due to inadequate waste disposal.
- With the rapid increase in population, the amount of waste in terms of quantity and quality has increased waste management pressure many-fold in recent years.
- Our health will be affected by dangerous industrial effluents, and be will be smothered by clouds of smoke and unhealthy gases.
Therefore, the reuse of goods and waste utilization should become a part of the production-consumption cycle. - For example, it is estimated that the per capita production of domestic waste is many times higher in a developed country hence compared to a developing country.
- Large quantities of solid, liquid and gaseous waste is produced by urban industrial communities in the form of plastic, paper, leather, tin cans, bottles, mineral refuse, and pathological waste from hospitals.
- Dead animals, agricultural wastes, fertilizer and pesticide overuse, and human and animal excreta are essentially rural concerns.
- This attitude towards waste has led to disastrous effects on the environment besides the overexploitation of natural resources.
5.1 Population growth
There is strong evidence that the growth of the world population poses serious threats to human health, socioeconomic development and the environment. It has taken only 12 years for the world population to grow from 5 billion to today's 6 billion. This is the shortest time ever to add 1 billion people — a number equivalent to the population of India or the combined population of the United States and Europe.
Some 10 000 years ago, when only about 5 million people inhabited the Earth, few biological systems were seriously damaged by human activity. Today, however, the world faces an environmental dilemma. Current demands are depleting many of the Earth's natural resources and ecological services. Within the next 50 years, it is likely that those life-supporting systems will somehow have to accommodate 3 billion more people as well as support desperately needed advances in living standards for those in poverty, particularly the 3 billion people now living on about $2 a day.
The impact of humans on their environment is related to population size, per capita consumption and the environmental damage caused by the technology used to produce what is consumed. The exploitation of technology and the high consumption pattern of people in Japan, Europe, the United States and Canada have a greater adverse impact per capita on the world's environment than that of a subsistence farmer in Bangladesh, for example. Although they represent 20% of the world's population, the 1.2 billion people living in developed countries consume an estimated 67% of all resources and generate 75% of all waste and pollution.
There are many important interactions between population growth, consumption, environmental degradation and health. Human activity has already transformed an estimated 10% of the Earth's surface from forest or rangeland into desert. The productive capacity of 25% of all agricultural lands, an area equal to the size of India and China combined, has already been degraded. Unproductive land and food scarcity currently contribute to malnutrition among 1 billion people, with infants and children suffering the most serious health consequences.
Environmental degradation, declining food security and uncontrolled epidemics of communicable diseases have slowed, and even reversed, the demographic transition to low death rates in some poor countries. In contrast to developed countries, where cardiovascular diseases and cancer are the leading causes of death, in poor countries infectious diseases cause 45% of all deaths.
Environment protection act
An Act to provide for the protection and improvement of environment and formatters connected therewith. Whereas the decisions were taken at the United Nations Conference on the Human Environment held at Stockholm in June, 1972, in which India participated, to take appropriate steps for the protection and improvement of human environment. The Environment (Protection) Act 1986 was introduced after the Bhopal gas tragedy during Rajiv Gandhi was the Prime Minister of our country.
OBJECTIVES
- To protect the forests and wildlife in the country.
- To improve the quality of life by protection of environment.
- To co-ordinate the activities of the various regulatory agencies already in existence.
Environment it includes water, air and land and the inter relationship which exists between water, air and land and human being, other living creatures, plants, micro organisms and property.
Environment pollutant
It means any solid, liquid or gaseous substance present in such concentration as may be injurious to environment pollutant.
Hazardous substance
It means any substance or preparation which, by reason of its chemical or physic-chemical properties or handling, is liable to cause harm to human beings, other living creatures, plant, micro-organism, property or the environment.
Environment pollution
It means the presence of any environmental pollutant in the environment. It includes all extraneous materials that are harmful to human being ,animals and plants life.
Sources And Causes For The Pollution
- Combustion
- Construction
- Mining
- Agriculture Chemical plants
- Coal-fired power plants
- Oil refineries
- Petrochemical plants, Nuclear waste
- Large livestock farms (dairy cows, pigs, poultry, etc.)
- PVC factories
- Plastics factories and other heavy industry are increasingly significant in the pollution equation.
Air(prevention and control of pollution)act
Air pollution refers to the release of pollutants into the air that are detrimental to human health and the planet as a whole. It is an undesirable change in the physical, chemical or biological characteristics of air. Sources of Air Pollution are:-
- Man-made
- Natural
Major Air Pollutants
- Carbon Monoxide
- Sulphur Dioxide
- Carbon Dioxide
- Chlorofluoro Carbon
- Nitrogen Oxide
- Ozone
Object
- To provide for the prevention, control and abatement of air pollution.
- To provide for the establishment of central and state board with a view to implement the Act.
- To confer on the boards the power to implement the provisions of the Act and assign to the boards functions relating to pollution.
Prevention And Control Of Air Pollution
- Power to declare air pollution control areas
- Power to give instructions for ensuring standards for emission from automobiles • Restrictions on use of certain industrial plants
- Person carrying on industry, etc. not to allow emission of air pollutants in excess of the standards laid down by State Board
- Power to take samples of air or emission and procedure to be followed in connection therewith
Environmental Pollutants
- Burning fossil fuel
Burning fossil fuels in cars and power stations releases SO2 and other green house gases.
- SO2 dissolve in rain – acid rain
Acid rain damages trees and pollutes rivers and lakes which Results in erosion of buildings and statues.
Penalties And Procedure
Failure to comply with the provisions of section 21 or section 22 or with the directions issued under section 31A.— (1) whoever fails to comply with the provisions of section 21 or section 22 or directions issued under section 31A, shall, in respect of each such failure, be punishable with imprisonment for a term which shall not be less than one year and six months but which may extend to six years and with fine, and in case the failure continues, with an additional fine which may extend to five thousand rupees for every day during which such failure continues after the conviction for the first such failure. (2) If the failure referred to in sub-section (1) continues beyond a period of one year after the date of conviction, the offender shall be punishable with imprisonment for a term which shall not be less than two years but which may extend to seven years and with fine.
Water(prevention and control of pollution)act
The Water Act was enacted by Parliament Act, 1974 purpose to provide for the prevention of control of water pollution and the maintaining or restoring of wholesomeness of water. As on day, it is applicable in all the states of India.
OBJECTIVES
- The water(prevention and pollution control) act 1974, provides for following:
- Prevention and control of water pollution
- Maintaining or restoring the wholesomeness of water
- Establishment of board for prevention and control of water pollution
- An act to provide for the levy and collection of a cess on water consumed by persons carrying on certain industries and by local authorities, with a view to augment the resources of the central board and the state boards for the prevention and control of water pollution constituted under the water (prevention and control of pollution) act, 1974.
Application and Commencement
It applies in the first instance to the whole of the States of Assam, Gujarat, Haryana, Himachal Pradesh, Jammu and Kashmir, Karnataka, Kerala, Madhya Pradesh, Rajasthan and West Bengal and the Union Territories.
POLLUTION
- Pollution means such as
- Contamination of water or
- Alternation of physical, chemical Or biological properties of water or
- Discharge of any Sewerage effluent Or trade Effluent Of or any other liquid or solid substance into water As may render such water harmful
- To public health
- To domestic , commercial , industrial, agriculture
- To life of animal And plant or aquatic Organisms.
Sewage effluent
Sewage effluent means effluent from Any sewerage system or Disposal works and Includes silage from open drains. Trade effluent Trade effluent includes . Any liquid ,solid or gaseous Substance Which discharge from any Premises Used for Carrying on Any industries operation or processes, or treatment And disposal system Other than domestic sewage.
Wildlife protection act
The Wildlife Protection Act, 1972 is an Act of the Parliament of India enacted for protection of plants and animal species. Before 1972, India only had five designated national parks.
Objectives
Prohibition on Hunting of Specified wild animals, birds and plants.
Setting up and management of national parks and wildlife sanctuaries.
Control of Trade and Commerce in wildlife and wildlife products.
Definitions under the Act
- "animal" includes amphibians, birds, mammals, and reptiles, and their young, and also includes, in the cases of birds and reptiles, their eggs.
- "animal article" means an article made from any captive or wild animal, other than vermin, and includes an article or object in which the whole or any part of such animal has been used and an article made therefrom.
- "hunting" includes
- Capturing, killing, poisoning, snaring, or trapping any wild animal, and every attempt to do so
- Driving any wild animal for any of the purposes specified in sub clause
- Injuring, destroying or taking any body part of any such animal, or in the case of wild birds or reptiles, disturbing or damaging the eggs or nests of such birds or reptiles.
- "taxidermy" means the curing, preparation or preservation of trophies
- Rugs, skins, and specimens of such animals mounted in whole or in part through a process of taxidermy
- Antler, horn, rhinoceros horn, feather, nail, tooth, musk, eggs, and nests.
- "wildlife" includes any animal, bees, butterflies, crustacean, fish and moths; and aquatic or land vegetation which forms part of any habitat.
- Hunting of Wild Animals • The Act prohibits hunting of wild animals. No person shall hunt any wild animals as specified in the schedules.
However there are some exceptions to it.
Sanctuary: - An animal sanctuary is a facility where animals are brought to live and be protected for the rest of their lives. • Unlike animal shelters, sanctuaries do not seek to place animals with individuals or groups, instead maintaining each animal until his or her natural death.
National Park:- A national park is a park in use for conservation purposes. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns.
Forest conservation act
Forest conservation is a practice of planning and maintaining forested areas for the benefit and sustainability for the generations.
The Forest Conservation Act of 1980 was acted to control deforestation.
Penalties for offences in Reserved Forests: – No person is allowed to set fire or clearings – Cattles are not permitted – No permission to collect any forests products
Protected forests – No permission to do anything for trees which are mentioned in Act.
REFERENCES :
1. Textbook Of Environmental Science By Deeksha Dave And E.Sai Baba Reddy, Cengage
Publications.
2. Text Book Of Environmental Sciences And Technology By M.Anji Reddy, BS Publication.
3. Comprehensive Environmental Studies By J.P.Sharma, Laxmi Publications.
4. Environmental Sciences And Engineering – J. Glynn Henry And Gary W. Heinke – Prentice Hall Of
India Private Limited.
5. A Text Book Of Environmental Studies By G.R.Chatwal, Himalaya Publishing House
6. Introduction To Environmental Engineering And Science By Gilbert M. Masters And Wendell P. Ela -
Prentice Hall Of India Private Limited.
