Class VIII-Chapter-7-Weather, Climate And Adaptations Of Animals To Climate

  • Rainfall is measured by an instrument called the rain gauge. It is basically a measuring cylinder with a funnel on top to collect rainwater. The day to-day condition of the atmosphere at a place with respect to the temperature, humidity, rainfall, wind speed, etc., is called the weather at that place.

  • Temperature, humidity, and other factors are called the elements of the weather

  • The average weather pattern taken over a longtime, say 25 years, is called the climate of the place

  • The western region of India, for example Rajasthan, will show that the temperature is high during most part of the year.

  • But during winter, which lasts only for a few months, the temperature is quite low.

  • This region receives very little rainfall.

  • This is the typical desert climate. It is hot and dry.

  • The northeastern India receives rain for a major part of the year.

  • Therefore, we can say that the climate of the north-east is wet.

(i) The polar regions

  • The polar regions present an extreme climate.

  • These regions are cove

  • red with snow and it is very cold for most part of the year.

  • For six months the sun does not set at the poles while for the other six months the sun does not rise.

  • In winters, the temperature can be as low as –37°C.

  • Animals living there have adapted to these severe conditions.

  • Polar bears, the penguin many types of fishes, muskoxen, reindeers, foxes, seals, whales, and birds have been seen in this region.

  • Siberian crane that comes from Siberiato places like Bharatpur in Rajasthan and Sultanpur in Haryana.



(ii) The tropical rainforests

  • The tropical region has generally a hot climate because of its location around the equator.

  • Even in the coldest month the temperature is generally higher than about 15°C.

  • During hot summers, the temperature may cross 40°C.

  • Days and nights are almost equal in length throughout the year.

  • These regions get plenty of rainfall.

  • An important feature of this region is the tropical rain forests.

  • Tropical rainforests are found in Western Ghats and Assam in India, Southeast Asia, Central America and Central Africa.

  • Because of continuous warmth and rain, this region supports wide variety of plants and animals.

  • The major types of animals living in the rainforests are monkeys, apes, gorillas, lions, tigers, elephants, leopards, lizards, snakes, birds and insects.

  • The lion-tailed macaque (also called Beard ape) lives in the rainforests of Western Ghats

  • Many tropical animals have sensitive hearing, sharp eyesight, thick skin and a skin colour which helps them to camouflage by blending with the surroundings.

  • This is to protect them from predators.

Class-IX-Chapter-14-Natural Resources

Resources On The Earth

  • The land, the water and the air, outer crust of the Earth is called the lithosphere,

  • Water covers 75% of the Earth’s surface comprise the hydrosphere,

  • Air-covers the earth is called the atmosphere, life-supporting zone of the Earth where the atmosphere, the hydrosphere and the lithosphere interact and make life possible, is known as the biosphere.

  • The air, the water and the soil form the non-living or abiotic component of the biosphere, carbon dioxide constitutes up to 95-97% of the atmosphere on Venus and Mars.

  • The percentage of carbon dioxide in our atmosphere is a mere fraction of a percent because carbon dioxide is ‘fixed’ in two ways:

  • Green plants convert carbon dioxide into glucose in the presence of Sunlight and

  • Many marine animals use carbonates dissolved in sea-water to make their shells.

  • Air is a bad conductor of heat.

  • When air is heated by radiation from the heated land or water, it rises.

  • Since land gets heated faster than water, the air over land would also be heated faster than the air over water bodies.

  • air rises, a region of low pressure is created and air over the sea moves into this area of low pressure,

  • During the day, the direction of the wind would be from the sea to the land

  • Rainfall patterns are decided by the prevailing wind patterns.




  • A Wonder Liquid Fresh water is found frozen in the ice-caps at the two poles and on snow covered mountains.

  • All cellular processes take place in a water medium


Water Pollution

  • Water dissolves the fertilisers and pesticides that we use on our farms.

  • The type of soil is decided by the average size of particles found in it and the quality of the soil is decided by the amount of humus and the microscopic organisms

  • found in it the topmost layer of the soil that contains humus and living organisms in addition to the soil particles is called the topsoil.

  • The quality of the topsoil is an important factor that decides biodiversity in that area

  • The large-scale deforestation that is happening all over the world not only destroys biodiversity, it also leads to soil erosion.



Biogeochemical Cycles

The Water-Cycle

  • The whole process in which water evaporates and falls on the land as rain and later flows back into the sea via rivers is known as the water-cycle,

  • As water flows through or over rocks containing soluble minerals, some of them get dissolved in the water.

  • Thus rivers carry many nutrients from the land to the sea, and these are used by the marine organisms

The Nitrogen-Cycle

  • Nitrogen gas makes up 78% of our atmosphere and nitrogen is also a part of many molecules essential to life like proteins, nucleic acids (DNA and RNA) and some vitamins.

  • Found in other biologically important compounds such as alkaloids and urea toothe nitrogen-fixing bacteria are found in the roots of legumes (generally the plants which give us pulses) in special structures called root nodules.

  • Other than these bacteria, the only other manner in which the nitrogen molecule is converted to nitrates and nitrites is by a physical process.

  • During lightning, the high temperatures and pressures created in the air convert nitrogen into oxides of nitrogen.

  • These oxides dissolve in water to give nitric and nitrous acids and fall on land along with rain.  Plants generally take up nitrates and nitrites and convert them into amino acids which are used to make proteins

  • Once the animal or the plant dies, other bacteria in the soil convert the various compounds of nitrogen back into nitrates and  A different type of bacteria converts the nitrates and nitrites into elemental nitrogen

The Carbon-Cycle

  • It occurs in the elemental form as diamonds and graphite

  • it is found as carbon dioxide in the atmosphere, as carbonate and hydrogen carbonate salts in various minerals,

  • while all life-forms are based on carbon-containing molecules like proteins, carbohydrates, fats, nucleic acids and vitamins.

  • The endoskeletons and exoskeletons of various animals are also formed from carbonate salts. Carbon is incorporated into life-forms through the basic process of photosynthesis which is performed in the presence of Sunlight by all life-forms that contain chlorophyll.

  • This process converts carbon dioxide from the atmosphere or dissolved in water into glucose molecules



The Oxygen-Cycle

  • In the crust, it is found as the oxides of most metals and silicon, and also as carbonate, sulphate, nitrate and other minerals.

  • It is also an essential component of most biological molecules like carbohydrates, proteins, nucleic acids and fats (or lipids) Oxygen from the atmosphere is used up in three processes, namely combustion, respiration and in the formation of oxides of nitrogen.

  • Oxygen is returned to the atmosphere in only one major process, that is, photosynthesis. the process of nitrogen-fixing by bacteria does not take place in the presence of oxygen.

Ozone Layer

  • ozone is poisonous,

  • It absorbs harmful radiations from the Sun

  • Various man-made compounds like CFCs (carbon compounds having both fluorine and chlorine which are very stable and not degraded by any biological process) were found to persist in the atmosphere.

Class-X-Chapter-15-Our Environment

Eco-system — what are its components?

  • All the interacting organisms in an area together with the non-living constituents of the environment form an ecosystem.

  • an ecosystem consists of biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil and minerals.



Food Chains and Webs

  • series or organisms taking part at various biotic levels form a food chain

  • Each step or level of the food chain forms a trophic level.

  • The autotrophs or the producers are at the first trophic level. They fix up the solar energy and make it available for heterotrophs or the consumers.

  • The herbivores or the primary consumers come at the second, small carnivores or the secondary consumers at the third and larger carnivores or the tertiary consumers form the fourth trophic level

Ozone Layer and How it is Getting Depleted

  • Ozone (O3) is a molecule formed by three atoms of oxygen.

  • While O2, which we normally refer to as oxygen, is essential for all aerobic forms of life.

  • Ozone, is a deadly poison.

  • at the higher levels of the atmosphere, ozone performs an essential function.

  • It shields the surface of the earth from ultraviolet (UV) radiation from the Sun.

  • This radiation is highly damaging to organisms, for example, it is known to cause skin cancer in human beings.

  • Ozone at the higher levels of the atmosphere is a product of UV radiation acting on oxygen (O2) molecule.

  • The higher energy UV radiations split apart some moleculer oxygen (O2) into free oxygen (O) atoms.

  • These atoms then combine with the molecular oxygen to form ozone as shown—The amount of ozone in the atmosphere began to drop sharply in the 1980s.

  • This decrease has been linked to synthetic chemicals like chlorofluorocarbons (CFCs) which are used as refrigerants and in fire extinguishers.

  • In 1987, the United Nations Environment Programme (UNEP) succeeded in forging an agreement to freeze CFC production at 1986 levels.



Class-X-Chapter-16th-Management of Natural Resources

  • Ganga Action Plan. This multi-crore project came about in 1985 because the quality of the water in the Ganga was very poor

  • Coliform is a group of bacteria, found in human intestines, whose presence in water indicates contamination by disease-causing microorganisms

  • three R’s to save the environment: Reduce, Recycle and Reuse.

Forests And Wild Life

  • Forests are ‘biodiversity hot spots’

Sustainable Management

  • The Chipko Andolan (‘Hug the Trees Movement’) was the result of a grassroot level effort to end the alienation of people from their forests. The movement originated from an incident in a remote village called Reni in Garhwal, high-up in the Himalayas during the early 1970s.

  • Himachal Pradesh had evolved a local system of canal irrigation called kulhs

Water Harvesting

  • Watershed management emphasises scientific soil and water conservation in order to increase the biomass production.

  • The aim is to develop primary resources of land and water, to produce secondary resources of plants and animals for use in a manner which will not cause ecological imbalance.

  • Watershed management not only increases the production and income of the watershed community, but also mitigates droughts and floods and increases the life of the downstream dam and reservoirs.

  • Water harvesting is an age-old concept in India. Khadins, tanks and nadisin Rajasthan, bandharasand talsin Maharashtra, bundhis in Madhya Pradesh and Uttar Pradesh, aharsand pynesin Bihar, kulhsin Himachal Pradesh, ponds in the Kandi belt of Jammu region, and eris(tanks) in Tamil Nadu, surangamsin Kerala, and kattasin Karnataka are some of the ancient water harvesting, including water conveyance, structures still in use today



Coal And Petroleum

  • Coal and petroleum were formed from the degradation of bio-mass millions of years ago and hence these are resources that will be exhausted in the future contain hydrogen, nitrogen and sulphur.

  • When combustion takes place in insufficient air (oxygen), then carbon monoxide is formed instead of carbon dioxide.

  • Of these products, the oxides of sulphur and nitrogen and carbon monoxide are poisonous at high concentrations and carbon dioxide is a green-house gas they are huge reservoirs of carbon and if all of this carbon is converted to carbon dioxide, then the amount of carbon dioxide in the atmosphere is going to increase leading to intense global warming.





  • The word environment is derived from the French word ‘Environ’ which means to ‘ encircle or surround’. The environment is a very broad concept and involves everything that affects an organism during its It is the totality of all social, biological, physical and chemical elements individually as well as collectively that composed nature and human made surrounding. It refers to the total of conditions which surround man at a given point in space and time. The environment is defined as the social, cultural and physical conditions that surround, affect and influence the survival, growth and development of people, animals or plants. As defined in the Environment (protection) Act, 1986, “environment includes water, air, land and the inter-relationships which exist among and between water, air, land and human being, other living creatures, plants, micro-organisms and property.

  • Environment:-

  • Hydrosphere

  • Atmosphere

  • Troposphere

  • Stratosphere

  • Lithosphere

  • Mountain

  • Plain

  • Desert

  • Biosphere

  • Plants

  • Animal

  • Sustainable development and use of paper that have a positive impact on the environment while air conditioning has a negative impact on the environment as it affects the Ozone Poverty alleviation has both positive and negative impact on environment. Alternatively, poverty is indirectly linked to the environment whereas sustainable development, use of paper bags and air conditioning directly affect the environment. So if we consider the positive impact on Environment from poverty alleviation.

  • The Environment (protection) Act of India was enacted in the year 1986 it extends to the whole of  India .

  • The environment may be divided into the biotic and abiotic The biotic environment is made up of biotic factors, that is all living things in the environment. The abiotic or physical environment is made up of all the physical factor that affect organism e.g.  temperature, light intensity , the amount of available water etc .



  • The concept of sustainable development was emphasised by the United Nations Conference on Environment and Development (UNCED), which defined it as “Development that meets the need of the present generation without compromising the ability of the future generation to meet their needs. Sustainable development is a matter of inter-generational sensibility in respect of the use of natural resources. The main objective of sustainable development is the just and prudent use of natural resources, it’s conservation and proper management. This term was explained in the WCED (World Commission on Environment and Development) report of 1987 titled “Our common future”. Sustainable development was fully supported in the Agenda-21 (Rio Declaration) declared in Earth Summit held in 1992. Besides, sustainable development was a prominent issue of the Johansburg summit 2002. Notably, the United Nations has indentified 17 sustainable development goals (SDGs) which have to be realised by 2030. A sustainable Development Index has also been initiated to measure the progress made by different nations in the direction of achieving these goals. The SDG index collects available data for 149 countries to assess where such each country stands. Importantly India was ranked 116th out of 157 nations in Sustainable Development Index 2017.

  • Renewable energy is a form of energy that is not the cause of pollution nor has its adverse effect on natural resources. Sustainable energy is the seventh goal of the 17 UN Sustainable Goals (SDGs), with a call to ensure access to affordable, reliable, sustainable and modern and modern energy for all-by 2030. The Sustainable Energy for all initiative act in support of the 2014-2024 decade of Sustainable Energy for All as declared by the UN General Assembly.

  • World Environment Day is celebrated on 5 June every year. India is the global host of 2018 World Environment Day with “Beat Plastic Pollution” as the theme of this year’s edition.

  • Natural capital includes all renewable and non-renewable environmental resources. It includes air, water, hand, minerals and forests. In another word only those resources, which are created by nature, without any human interference, can be deemed natural capital. Hence roads cannot be included in country’s natural capital.



  • Natural Resources –

  1. Inexhaustible Resources

  • Solar Energy

  • Wind Energy

  • Tidal Energy

  • Rain

  • Atomic Energy

  1. Exhaustible Resources

  • Renewable

  • Forest

  • Pasture

  • Water System

  • Agriculture System

  • Wild Animal

  • Soil

  • Non Renewable

  • Biotic – Biotic Species

  • Abiotic

  • Petrol

  • Coal

  • Gas

  • Gypsum

  • Metals



  • The water cycle is driven primarily by the energy from the sun. This solar radiation drives the cycle by evaporating water from the oceans, lakes, river and even the soil. It forms water vapor and clouds, where water droplets eventually gain enough mass to fall back to earth. The water cycle is essentially a closed system, meaning that the volume of water that is the hydrosphere today is the same amount of water that has always been present in the earth system.

  • The National Environmental Engineering Research Institute (NEERI) is a research institute created and funded by Government of India. It was established in Nagpur in 1958 with focus on water supply, sewage disposal, as Central Public Health Engineering Research Institute (CPHERI) related diseases and to some extent on industrial pollution and occupational diseases found common in post-independent India. NEERI is a pioneering laboratory in the field of environmental science and engineering and part of Council of Scientific and Industrial Research (CSIR). NEERI has five zonal laboratories at Chennai, Delhi, Hyderabad, Kolkata and Mumbai. NEERI falls under the Ministry of Science and Technology, Government of India.

  • Conservation of biological diversity, prevention and control of pollution, decreasing poverty, all are important for Sustainable Development. It is imperative for achieving the goal of sustainable development to make policies on information about our environment and ecology. Presently sustainable development has become an alternative approach to the theories of development. Certain information required for policy formulation on sustainable development are:



Important information for sustainable development

Related to environment

  • Natural habitat

  • Natural resources

  • Fundamental factors of environment

  • Status of environment

Related to human activity

  • Population growth rate

  • Size of population

  • Resources and food availability

  • Non-compulsory structural facility is

  • Average standard of living and per capita income

  • Level of Technology

  • The first Earth Summit by United Nations Conference on Sustainable Development was held in Rio-de-Janeiro. In 2012, the United Nations Conference on Sustainable Development was also held in Rio, and is also commonly called Rio +20 or Rio Earth Summit 2012.


  • Agenda-21

  • Survey of biological diversity and protection of endangered species

  • Poverty eradication and population control in developing countries

  • Stress on generous capital transfer

  • Food, clean water and social security to everyone

  • The United Nations Conference on Sustainable Development (UNCSD) also known as Rio 2012, Rio +20 or Earth Summit 2012 was the third international conference on sustainable development hosted by Brazil in Rio de Janeiro. The primary result of the conference was the non-binding document “The future we want” a 49-page action plan.

  • The thin layer of gases surrounding the earth is called the atmosphere. The majority of the Earth’s atmosphere consists of a high amount of nitrogen, along with smaller amounts of oxygen and carbon dioxide.

  • Air is a mixture of gases. By volume, about 78% of this mixture is nitrogen and about 21% is oxygen. Carbon dioxide, argon, methane, ozone and water vapour are also present in very small quantities.



  • The air around us is a mixture of gases, mainly nitrogen and oxygen, but containing much smaller amounts of water vapour, argon and carbon dioxide and very small amounts of other gases.

Gas                                      Percentage

Nitrogen             N2              78.08%

Oxygen              O2              20.95%

Argon                 Ar              0.93%

Carbon dioxide  CO2            0.038%

Neon                  Ne             0.0018%

Helium               He             0.005%

Methane             CH4           0.00017%


  • We need oxygen to survive and we depend on trees to provide this oxygen. To make food for themselves, trees go through a process known as photosynthesis where they take in carbon dioxide from the air and release oxygen back into the atmosphere.

  • Trees contribute to the environment by providing oxygen, improving air quality, climate amelioration, conserving water, preserving soil and supporting wildlife. Hence they clean the environment and are not the reason behind air pollution. In addition to this, trees on both sides of roads reduce the sound pollution by reducing the intensity of sound by 10 to 15 decibels.

  • Decay of organic matter, volcanic action and respiration and burning of fossil fuel etc contribute carbon dioxide to the carbon cycle, whereas plants are use carbon dioxide in the process of photosynthesis. Thus plants do not add carbon dioxide to the carbon cycle rather they release oxygen and consume carbon dioxide. Three natural allotropes of carbon are – amorphous, graphite and diamond. Besides, as a compound, it is found as carbon dioxide, carbonate and Hydrogen carbonate.

  • The World Meteorological Organization (WMO) provides a framework for international cooperation in the development of meteorology and operational hydrology and their practical application. WMO Originated from the International Meteorological Organization (IMO) which was founded in 1873 to facilitate the exchange of weather information across national borders. WMO become a specialized agency of the United Nations o 17 March, 1951. Notably World Meteorological convention was implemented on 23 March, 1950. It has it’s headquarters in Geneva, Switzerland.

  • Weathering is defined as mechanical disintegration and chemical decomposition of rocks through the actions of various elements of weather and climate. Weathering processes are conditioned by many complex geological, climate, topographic and vegetative factors.

  • Greenpeace is a non-governmental environmental organization with offices in over 40 countries. It is headquarters in Amsterdam, Netherlands. Greenpeace states its goal is to “ensure the ability of the Earth to nurture life in all its diversity”.



  • Eco-mark is a certification mark issued by the Bureau of Indian Standards (The National Standards Organization of India) to products conforming to a set of standards aimed at ensuring the least impact on the ecosystem. The marking scheme was started in 1991.

  • Environment Protection Agency (EPA) is an energy of the Federal Government of the United States switch was created for the purpose of protecting human health and the environment by writing and enforcing regulations based on laws passed by the Congress. It was established on 2 December, 1970.

  • The National Environment Appellate Authority (NEAA) better known as NEA was set up by the Ministry of Environment and Forest to address cases in which environment clearances were required in certain restricted areas. It was established by the National Environment Appellate Authority Act 1997 to hear appeals with respect to restriction of areas in which any industries, operations or processes shall or shall not be carried out, subject to certain safeguards under the Environment (Protection) Act, 1986. On the establishment of National Green Tribunal on 18th October, 2010, under National Green Tribunal Act, 2010 the NEAA stands dissolved.

  • Sustainable agriculture is the production of food, fiber or other plants or other animal products using farming technique that protect the environment, public health, human communities and animal welfare. In short, it is proper utilization of the land without affecting the environment so that it’s quality remain intact. Use of chemical fertilizers and pesticides has adversely affected the soil health.

  • Extreme urbanization and industrialization is harmful to balanced development, environment and ecology and biodiversity conservation.

  • Marked of Punjab and Sayag Group of Israel signed an agreement to grow vegetable in greenhouses farming on 21 April, 2001.

  • The National Green Tribunal was established on 18 October, 2010 under the National Green Tribunal Act, 2010 for effective and expeditious disposal of cases relating to environmental protection and conservation of forest to provide the right to healthy environment, construed as a part of Right to like under Article 21.

  • William M. Adams is the author of the book Green Development: Environment and Sustainability in a Developing World. It’s first edition was published in 1990.

  • In the year 1997, the World Environment Conference was organised in Kyoto, Japan. The Kyoto Protocol to the United Nations Framework convention on climate Change was adopted in this conference which came into existence on 16 February, 2005.

  • Environmental degradation is the deterioration of the environment through depletion of resources such as sir, water and soil. Environmental degradation is either natural or by human beings.

  • Many transplanted seeings do not grow because most of the root hairs are lost during transplantation. The function of root hairs is to collect water and mineral nutrients present in the soil and take this solution up through the roots to the rest of the plant. These are made up of cellulose and nominal Pectin which helps it as a gelling agent with the soil. Another reason is the use of fertilizers which increases the concentrations of the soil and make it difficult for plants to absorb water. This situation causes diseccation of plants causing the leaves to turn brow.

  • Protection of the ecological balance is directly related to the forest policy and the Environmental Protection Act, 1986. While industrial policy and education policy also include the environmental approach. Thus the four policies mentioned in question could be considered as being related to the protection of ecological balance.



  • The Global Environment Facility (GEF) was established on the eve of the 1992 Rio Earth Summit to help tackle our planet’s most pressing environmental problems. GEF is an international partnership of 183 countries and 18 agencies that addresses global environmental issues. It is a financial mechanism for five major international conventions: The Minamata convention o Mercury, the stockholm convention on Persistent Organic Pollutants, the United Nations Convention on Biological Diversity, the United Nations Convention to combat Desertification and the United nations Framework convention on Climate Change.

  • Plachimada is a small village in Palakkad district of Kerala. It is situated in Chittur block’s Perumatty Panchayat of the district. In 2000, this panchayat gave license to the Hindustan Coca-Cola Beverages Private Limited (HCCBPL) to manufacture Coca-Cola (Coke) and other products viz. Fanta, Limca, Thums Up, Sprite, Kinley etc. But very soon due to the contamination of groundwater in that locality by the chemical waste discharged by the company, local people started a small-scale protest against the company; Later this protest was supported by the Panchayat authorities. In the long run, with national as well as international support to this protest against a multinational company (MNC), this movement became an icon of other such movements worldwide.

  • Environment Protection Act, 1986 is also known as umbrella legislation. In the wake of the Bhopal Tragedy, the Government of India enacted the Environment Protection Act of 1986 under Article 253 of the Constitutions. The act is an “umbrella” legislation designed to provide a framework for Central Government coordination of the activities of various Central and State authorities established under previous laws, such as the Water Act and the Air Act.

  • The Genetic Engineering Appraisal Committee is constituted under the Environment (protection) Act On 22nd July, 2010 Genetic Engineering Appraisal Committee was renamed as genetic engineering appraisal committee. It is the Apex body constituted in the ministry of Environment and Forest under ‘ rule of manufacture, use, import, export and storage of hazardous microorganism/genetically engineered organism or cells 1989 ‘ under the Environment protection Act 1986.

  • National Geographic conducted its inaugural Greendex survey in January That first Greendex survey of 14 countries around the world ranked average consumers in those countries according to the environmental sustainability of their behaviour. In 2009 India was at first place and in 2014 too India retained its position.

  • Mixed cropping, organic manure, nitrogen fixing plants and pest resistant crop varieties are the best strategy for environment- friendly sustainable development in Indian agriculture.

  • Masanobu Fukuoka was a Japanese farmer and philosopher famous for his natural farming and revegetation of desertified lands.

  • The green Army is a six month program for 17 -24 years old youths in Australia to train and work for the Green Army projects include restoring native vegetation, heritage restoration, protecting animal habitats and regenerating wetlands in urban, rural and remote areas. The green Army program will close on 30 June 2018.




  • The word ecology originates from Greek “Oikos” meaning house or environment. Ecology is the study of interactions among organism and their environment. It also includes the study of organismal interaction with abiotic components of their environment. The word “ecology” (Okalogie) was coined by German scientist Ernst Haeckel (1834-1919). Haeckel defined Ecology as the study of the relationship of organism with their environment. Another definition offered by Eugene Odum defines Ecology as the study of ecosystem. Ecology in current age refers to a broader spectrum encompassing not only plants, animal species and climate but also to human beings and it’s physical surroundings.

  • An ecosystem is a community of living organisms in conjunction with the non-living components of their environment (things like air, water and mineral soil), interacting as a system.



  • Important features of ecology are:

  • It is normally an open system with a continuous, but variable influx and loss of materials and energy.

  • An ecosystem is an overall integration of the whole mosaic of the interacting organism and their environment.

  • It is a basic functional unit with no limits of boundaries.

  • It consists of biotic and abiotic components interacting with each other.

  • It’s functional unit is capable of energy transformation, circulation and accumulation.

  • Different types of the ecosystem are present in different areas.

  • The term ecosystem was first used by A.G. Tansley in 1935 who defined an ecosystem as ‘a particular category of physical systems, consisting of organisms and inorganic components in a relatively stable equilibrium, open and of various sizes and kinds. An Ecosystem is a community of living organism (plants, animals and microbes) along with the nonliving components of their environment (like air, water, mineral, soil etc) interacting as a system. These biotic and abiotic components are considered as linked together through nutrient cycles and energy flows. As ecosystem are defined b the network of interactions among organisms and between organisms and their environment, these can vary in size from as small as drop in the pond to so large as an ocean. The earth itself is a large ecosystem.

  • All the organisms and the abiotic components of the environment from the ecosystem of the place. Thus ecology deals with the organism and it’s environment.

  • An artificial ecosystem meets all the criteria of a natural ecosystem but is made and controlled by humans. Orchards, farmlands, gardens and human-made reservoirs are some examples of artificial ecosystems. Ecosystems can broadly be categorized as Acquatic and terrestrial ecosystems.  Grasslands, forests and desert are examples of terrestrial ecosystems while lakes, river and oceans fall under aquatic ecosystem. Ecosystems can be classified as:



  • Forest

  • Grass land

  • Desert


  • Non-saline water

  • Pond

  • Lake

  • Waterfall

  • Saline Water

  • Saline lake

  • Estuary

  • Ocean


  • Farmland/Grainery

  • Aquarium

  • Space ship



  • Ecological niche characterizes the position of a species within an ecosystem, comprising species habitat requirements as well as its functional role.

  • Wildlife conservation and prevention of environmental pollution is helpful in maintaining ecological balance. Deforestation adds to the environmental imbalance.

  • There are mainly two kinds of ecosystems – Aquatic and Terrestrial. Marine ecosystems are the biggest ecosystems, which cover around 71% of Earth’s surface and contain 97% of our planet’s water.

  • Deforestation is one of the main causes of the ecological imbalance in India. While, desertification, floods and famines and rainfall variations are secondary causes.

  • Aquatic ecosystem refers to living and non-living parts of a water body and the interactions that take place among them. Aquatic ecosystems can be categorised in marine ecosystem and fresh water ecosystem. Marine ecosystem covers approximately 70% of the earth’s surface and contain approximately 97% of the planet’s water. Approximately 85% of the dissolved materials in sea water are sodium and chlorine.

  • There are four types of trophic levels in the food chain of the ecosystem. They are –

  • First trophic level –        Producer

  • Second trophic level      –        Primary consumers (herbivorous)

  • Third trophic level –        Secondary consumers (carnivorous)

  • Fourth trophic level –        Tertiary consumers (omnivorous)

  • Biotic components are the living things that shape an ecosystem.

Biotic components usually include:

  • Producers –        g. plants

  • Consumers –        g. animals, humans

  • Decomposers – g. fungi and bacteria

  • Solar energy is the primary source of energy in the ecological body.

  • Mainly herbivores, in a food chain, are considered as primary consumers. Ants fall under decomposer and primary consumers both. It eats plants and receives energy from cellulose. Tiger is carnivorous and fox is omnivorous. Significantly, primary consumers feed on primary producers (plants).

  • In food chain there are trophic levels i.e., autotroph, primary consumer, Secondary consumer and Tertiary consumer. The primary consumer is the herbivores (that feed on the plant), the secondary consumer is small carnivores (feeding on primary consumer) and the tertiary consumer is larger carnivores. So in food chain man is the primary as well as secondary consumer who feeds on both plant, products and meat.

  • The ten percent law of transfer of energy from one tropic level to the next was introduced by Raymond Linderman in 1942. According to this law, during the transfer of energy from organic food from one tropic level to the next, only about ten percent of the energy from organic matter is stored as flesh. The remaining if lost during transfer, broken down in respiration or lost to incomplete digestion by higher tropic level. When organisms are consumed, 10% of the energy in the food is fixed into flesh and is available for next tropic level (carnivores or omnivores). When a carnivore or an omnivore consumes that animal, only about 10% of energy is fixed in its flesh for the higher level. Thus, at every level of food chain (first, second, third and top level), the consumer converts only 10% of the accumulated energy into his body weight.

  • Phytoplankton, also known as microalgae are similar to terrestrial plants in that they contain chlorophyll and require sunlight to live and grow. Most phytoplankton are buoyant and float in the upper part of the ocean, where sunlight penetrates the water. Phytoplankton also require inorganic nutrients such as nitrates, phosphates and sulfur which they convert into proteins, fats and carbohydrates.



Primary Producer



Ocean or deep water

Rooted Plants

Shallow water

Grasses of different kind and forest plants


Crop Plants



  • Plants are self feeding organisms that produce complex organic compound such as carbohydrates, fats and proteins generally using energy from light (photosynthesis). These are known as autotrops and are fundamental to the food chain of all ecosystems. These are called primary producers.

  • Eucalyptus consumes more water than other trees. That is why it often called “enemy of environment”. The water level goes down across the area of Eucalyptus plantation. These plants are mostly found in Australia.

  • Lentic Ecosystem refers to the static water habitats like ponds, lakes, swamps and marshes. Lotic Ecosystem refers to the dynamic water habitats like rivers.

  • DDT is non-biodegradable, biomagnifying pollutant which increases in concentration from producers, primary consumers, secondary consumers to tertiary consumers.

  • The oceans are the cradle of life on Earth which harbour the highest level of biodiversity. No terrestrial ecosystem can match the biological richness of a coral reef, not only in some species, but also in variety and originality of survival strategies.

  • Water management, afforestation and wildlife protection is associated with Ecological balance while industrial management is not associated with ecological balance.

  • “Ecology is permanent economy” is the slogan of Chipko Movement. “Narmada Bachao Andolan was against the construction of a multi modal dam on the narmada river. “Apiko Movement” was started in Karnataka for environment protection.



  • The Chipko movement was a forest conservation movement in India started on 26 March, 1974. Gaura Devi gathered other women around her village in the Garhwal Himalayas and prevented loggers from felling trees by sticking to the trees. This act by illiterate tribal and village women to reclaim their traditional forest rights was a dramatic moment known as “Chipko Andolan”, a non-violent struggle that gave birth to the modern Indian environmental movement.

  • In Earth science, a biogeochemical cycle is a pathway by which a chemical substance moves through both biotic and abiotic components of Earth. Biogeochemical cycles of nitrogen, phosphorus and carbon etc. are found in nature.

  • The flow of energy in the ecosystem is unidirectional (or one-directional). The energy enters the plants (from the sun) through photosynthesis during the making of food. This energy is then passed on from one organism to another in a food chain. The energy given out by the organisms as heat is lost to the environment. It does not return to be used by the plants again. This makes the flow of energy in ecosystem “unidirectional”. According to the first law of thermodynamics energy cannot be created or destroyed in an isolated system. According to the second law whenever energy transform to a new form, there is evident decay in it’s intensity. Similarly, with increasing trophic levels availability of energy decreases in the natural ecosystem.

  • Arne Naess was a Norwegian philosopher who coined the term “deep ecology” in 1973.

  • Joseph Grinnell referred to the “ecological or environmental niche” as the ultimate distributional unit of “species and subspecies”.



  • Wildlife Protection          –        1972

  • Environment Protection Act          –        1986

  • The Scheduled Tribes and other Traditional –        2006

Forest Dwellers (Recognition of Forest Rights Act)

  • The Forest Conservation Act                         –        1980

  • In ecology, bionomics (Greek: bio=life; nomos=law) is the comprehensive study of an organism and its relation to its environment. Another way of expressing this word is the term currently referred to as “ecology”. It stresses on the value of natural systems which influence human systems and is not related to management of life.

  • Pycnolcine indicate density gradient of any water system. Halocline shows salinity gradient of water system. Thermocline shows change in temperature with respect to depth of a water system.

  • Marine upwelling is a process of replacement of hot water o f the surface of the sea with old, concentrated water full of nutrients.

  • Ecological succession is the gradual process by which ecosystems change and develop over time in grassland, trees have already been cleared away due to fires in the past, which also changes the ground composition. Without the trees to hold them, water washes away most of the soil and the underlying ground becomes the pioneer population, which is then replaced by grass. The grass however absorbs most of the water before it reaches the roots of the shrubs. Thus the ecological succession does not occur beyond the grass.

  • element studied different species of plants and gave a generally agreed upon definition in 1916. According to him, biotic succession is a natural process of displacement of one particular community by another in particular area. Scientist named Odum described it as a sequenced process. The correct order of biotic succession is as follow:

Nudation – Migration – Ecesis – Reaction – Stabilization



  • The diverse range of organisms (plants and animals) found in an ecosystem, is defined as bio-diversity. The species are organised in different communities which are found in a particular ecosystem. Bio-diversity is denoted with (a) alfa, (b) bita and (g) gama indicating different categories. This classification was advanced by Whittaker in 1972.

  • The most significant aspect of biodiversity is the maintenance of ecosystem. Bio-diversity functions on different levels of species, communities and eco systems.

  • Habitat loss is one of the biggest threats to biodiversity. Cutting of forests to create fields, filling in wetlands to build houses, and creating dams that change river flow, are all examples of habitat destruction.



  • The main cause of the loss of biodiversity is the influence of human beings on the world’s ecosystem. The threats to biodiversity can be summarized the following main points:

  • Alteration and loss of the habitats

  • Introduction of exotic species and genetically modified organisms

  • Pollution

  • Climate Change

  • Overexploitation of resources

  • Natural habitat destruction is the main reason for the decrease in biodiversity as the transformation of the natural areas determines not only the loss of the plant species but also a decrease in the animal species associated with them.

  • The United Nations has proclaimed May 22 as the International Day for Biological Diversity, white many other countries celebrate 29 December as biodiversity day. It is notable that on 29 December, 1993 the convention of biological diversity came into force.

  • Global warming, fragmentation of habitat and invasion of alien species can be threats to the biodiversity of a geographical area while promotion of vegetation is not responsible for the same.

  • Threat to biodiversity

  • Habitat loss and degradation

  • Climate change and pollution

  • Rehabilitation of exotic species

  • Extinction of species

  • Natural extinction

  • Mass extinction

  • Human induce of extinction

  • Eastern Himalayas is a biodiversity hotspot, Mediterranean region and southwest Australia is also biodiversity hotspot.

  • “Conservation International” has released an updated list of 35 bio-diversity hot spots worldwide. It lists Western Ghats and eastern Himalayas of India also. Notably in February, 2016, CEPF (Critical Ecosystem Partnership Fund) declared the North America coastal Plains as 36th bio-diversity hotspot.

  • Five main threats to biodiversity are commonly recognised in the programs of the conventional-invasive alien species, climate change, nutrient loading and pollution, habitat change and over-exploitation.

  • Hotspots are not only located in tropical regions but also in temperate regions (California floristic province, Japanese Islands). India has four bio-diversity hot spots- Eastern Himalayas, Western Ghats, Indo-Myanmar border and Sundaland Bio-diversity hotspot falls under Indo-Myanmar border and Sundaland area. Western Himalayas and Andaman and Nicobar Islands are not biodiversity hotspots.

  • India is a land of remarkable bio-diversity. India inhabitates 7.6 percent of all mammals, 12.6 percent of birds, 6.2 percent of reptiles and 4.4 percent of amphibians found in 18 mega-diverse countries.

  • A biodiversity hotspot is a bio-geographical region of the Earth which is extremely biologically diverse and also under severe threat due to habitat loss, climate change or extensive species loss. As a general rule, to be considered a biodiversity hotspot, a region must be biologically diverse, with a high proportion of endemic species which are not found anywhere else on Earth, and the security of the region must be threatened. So, hotspots are the richest and most threatened reservoirs of plant and animal life on Earth.



  • India has four bio-diversity hot spots –

  1. Western Ghats

  2. Himalayas

  3. Indo-Myanmar border

  4. Sundaland

  • The tallest known tree is Redwood (Sequoia). It is found in California (U.S.A.). This species includes the tallest living trees on Earth, reaching up to 379 feet (115.5 m) in height.

  • The “Red Data Books” published by the International Union for  Conservation of Nature and Natural Resources (IUCN) contain lists of threatened plants and animal species.

  • Endangered species are listed in Red Data Book.

Benefits of IUCN list

  • Raising awareness about importance of endangered species

  • In situ Direction of conservation work

  • Identification and record of endangered species

  • Formation of written list of loss of biodiversity

  • Great Indian Bustard is a highly endangered species.



  • According to ENVIS centre for Faunal Diversity hosted by Zoological Survey of India sponsored by Ministry of Environment, Forest and Climate Change, below is the risk status of the animals –

Golden Langur            –        Endangered

Hoolock Gibbon         –        Endangered

Asiatic Wild Dog        –        Endangered

Desert Cat                   –        Least Concern

  • By 36th Constitutional Amendment Act, 1975 Sikkim was made full fledged State of the Union of India. It is considered as a botanist paradise because it lies under hotspots of northern Himalaya which is rich in biodiversity. Population over here mainly comprises of Lepchas and Nepalis.

  • India’s human population is growing at an outstanding pace but the bird population is shrinking fast mainly because there has been a large-scale reduction in the habitats of the birds and there has been a excessive use of pesticides, chemical fertilizers and mosquito repellents. Pesticides like D.D.T. enters into the food-chain and cause untimely ravelling of bird’s eggs. This cause decrease in birds’s population.

  • The most important strategy for the conservation of biodiversity together with traditional human life is the establishment of biosphere reserves. A biosphere reserve is an integral part of the human system. In these areas multifaceted development of ecosystem is given prominence.

  • The main objective of biosphere reserves are –

  • To contribute to the conservation of landscapes, ecosystems, species and genetic variations.

  • To foster economic and human development which is socio-culturally and ecologically sustainable

  • To provide support for research, monitoring, education and information exchange related to local, national and global issues of conservation and development


  • The Indian Government has established 18 Biosphere Reserves in India, which protects larger areas of natural habitat. Ten of the eighteen biosphere reserves are part of the World Network of Biosphere Reserves, based on the UNESCO Man and the Biosphere (MAB) programme list –

  • Nilgiri Biosphere Reserve

  • Gulf of Mannar Biosphere Reserve

  • Sundarbans Biosphere Reserve

  • Nanda Devi Biosphere Reserve

  • Nokrek Biosphere Reserve

  • Pachmarhi Biosphere Reserve

  • Simlipal Biosphere Reserve

  • Great Nicobar Biosphere Reserve

  • Achanakmar- Amarkantak Biosphere Reserve

  • Agasthyamala Biosphere Reserve

  • For conservation of flora, Botanical Gardens do not come under in-situ method while Biosphere Reserves, National Parks and Wilds Life Sanctuaries fall under in-situ method.

  • Establishment of Biosphere Reserve is an important strategy for the conservation of Biodiversity. Biosphere Reserves are areas of terrestrial and coastal ecosystems promoting solutions to reconcile the conservation of biodiversity with its sustainable use. Notably, in Situ and Ex-Situ techniques are adopted for the conservation of bio-diversity.

  • The maximum biodiversity is found in tropical rain forest. They extend from 100 North to 100 South longitudes. This area has a suitable condition for growth and development of flora and fauna as it has heavy rains and high temperature throughout the year.  That is why it is also called as optimum Biome.



  • Bio-diversity refers to a variety of organism found in a particular geographical area. Utmost bio-diversity is found in tropical rain forests among all ecosystems on the Earth. Tropical rain forest extends near the equator.

  • The richest biodiversity if found in Silent Valley in Kerala. It is located in Palakkad District of Kerala, India. Silent Valley is rectangular, twelve km from north to south and seven km. from east to west. It is located between 11003’ to 11013’ N (latitude) and 76021’ to 76035’ E (longitude). It is a part of the Western Ghats.

  • Long before the internet era, a remarkable people’s movement saved a pristine moist evergreen forest in Kerala’s Palakkad district from being destroyed by a hydroelectric project. In 1986, Silent Valley was declared a national park.

  • “Valley of Flowers” is situated in the Chamoli Districts of Uttarakhand.

  • The list of Ramsar Sites comprises wetland of international importance. India currently has 26 sites designated as wetlands of international importance (Ramsar Sites).



Name of the  Site


Asthamudi Wetland


Bhitarkanika Mangroves


Bhoj Wetland

Madhya Pradesh

Chandertal Wetland

Himachal Pradesh

Chilika Lake


Deeper Beel


East Calcutta Wetlands

West Bengal

Harike Lake


Hokera  Wetland

Jammu and Kashmir

Kanjli Lake


Keoladev Ghana NP


Kolleru Lake


Nalsarovar Bird Sanctuary


Point Calimere

 Tamil Nadu

Pong Dam Lake

Himachal Pradesh

Renuka Wetland

Himachal Pradesh

Ropar Lake


Rudrasagar Lake


Sambhar Lake


Sasthamkotta Lake


Surinsar-Mansar Lakes

Jammu and Kashmir

Tsomoriri Lak

Jammu and Kashmir

Vembanad Kol Wetland


Upper Ganga River (Brijghat to Narora  Stretch)

Uttar Pradesh

Wular Lake

Jammu and Kashmir

Point Calimere

 Tamil Nadu

  • World Wetlands Day is celebrated every year on 2 February. This day marks the date of the adoption of the Convention on Wetlands on 2 February, 1971, in the Iranian city of Ramsar. The theme of World Wetlands day 2018 was “Wetlands for Sustainable Urban Future”.

  • The Ramsar Convention is associated with the conservation and sustainable use of wetlands. It is also known as the Conventional on Wetlands. It was signed on 2 February, 1971 at Ramsar in Iran. That date is celebrated as World Wetland Day now.

  • The total coral reef in India is 5790 km2, distributed between 4 major regions: Lakshadweep, Gulf of Mannar, Gulf of Kutch, and Andaman and Nicobar Islands. Fringing reefs are common. They occur around the Gulf of Mannar, Gulf of Kachchh, Andaman and Nicobar Islands. Atoll reefs are found in Lakshadweep. Sundarban is known for mangrove forest.

  • The Cartagena Protocol is an international agreement on bio-safety. It was adopted on 29 January 2000 and implemented on 11 September 2003. India confirmed bio-safety on Cartagena Protocol on 23 January 2003.



  • The word biodiversity is a contraction of the phrase “biological diversity” and was first coined in 1985 by Walter Rosen of the National Research Council as a title word in a seminar, organized to discuss biological diversity.

  • Warmer water temperature can result in coral bleaching. When water is too warm, corals will expel the algae (zooxanthellae) living in their tissues causing the coral to turn completely white. This is called coral bleaching.

  • The National Biodiversity Authority (NBA) was established in 2003 to implemented India’s Bio-Diversity Act (2002). The headquarters of NBA is in Chennai, Tamil Nadu.

  • The United Nations General Assembly declared 2011-20 the United Nations Decade on Biodiversity (Resolution 65/161) on 22, December 2010.

  • Biodiversity Act was passed by Indian Parliament on 11, December 2002.

  • In May, 2003 a scientist working with the Peregrine Fund presented a research paper that confirmed that the vulture deaths were due to the anti-inflammatory painkilling drug diclofence sodium. A vulture that had gout had high levels of diclofenac in their kidneys. In January, 2004 the results of a joint study conducted by the Peregrine Fund and the Ornithological Society of Pakistan confirmed that diclofenac sodium was indeed the primary reason for vulture deaths manufacturing of veterinary diclofenac by the Drug Controller General of India. The devastating effect of this medicine can be understood from the fact that it caused death of 8.5 crore vultures in India, Nepal and Pakistan in 10 years. This ban was soon introduced in Nepal and Pakistan.

  • Seabuckthorn is a medicinal plant found in the Himalayan region. Our country holds tremendous potential in respect of Seabuckthorn fruit production and diverse varieties which have health-promoting properties and can play a crucial role in preventing soil erosion and help nitrogen fixation in cold and desert areas. Seabuckthorn fruits grow in the cold deserts of Ladakh region of Jammu and Kashmir, Lahaul-Spiti in Himachal Pradesh and some parts of Arunachal Pradesh.

  • Doda was a giant bird with short stumpy legs and a large hooked beak. It used to live on the Indian Ocean islands of Mauritius but had completely vanished by the end of the 17th Dodo was helpful in pollinating and propagating seed of the species called Tambalacoque.

  • Dugong known as “Sea Cow” is mostly found in Eastern Africa, South Asia and Australia. In India, it is found in the Gulf of Mannar and Palk Bay. Feeding on sea grass dugongs are found in sea grass beds, sheltered waters, lagoons and Bays. It has been given legal protection under Schedule I of the Wildlife (Protection) Act, 1972.



  • Dugong is a medium-sized marine mammal, which is vulnerable to extinction.

  • The criteria for the recognition of regions are hotspot are species richness, endemism and threat perception that led to the recognition of Western Ghats, Sri Lankan and Indo-Burma regions as hotspots of biodiversity.

  • Bird Life International is a global partnership of conservation organizations that strives to conserve birds, their habitats and global biodiversity. It is the world’s largest partnership of conservation organizations, with 119 partner organizations. This organization identifies important bird and bio-diversity areas. It has so far identified more than 12000 such areas. Concept of bio-diversity hot spots was propounded by British environmentalist Norman Myres. 

  • The First Meeting of the Parties (MOP 1) to the Cartagena Protocol on Bio-safety was held on 23-27 February, 2004 in Kualalumpur, Malaysia.

  • Rann of Kutch is the natural habitat of Indian wild ass. This animal has no predators in that area but its existence is threatened due to the destruction of its habitat.

  • The tenth meeting of the Conference of the Parties (COP 10) was held in Nagoya, Japan from 18 to 29 October, 2010. The eleventh meeting of the Conference of the Parties (COP-11) was held in Hyderabad, India, from 8 to 19 October, 2012. The twelfth meeting of the Conference of the Parties (COP-12) was held in Pyeongchang, Republic of Korea from 6-17 October, 2014. Thirteenth meeting of the Conference of the Parties (COP-13) was held in Cancun, Mexico, from 4-17 December, 2016.

  • UN-REDD (Reducing Emmission from deforestation and forest degradation) is an inter-institutional programme under the aegis of UNFCCC member countries. This programme was started in 2008. Institution like UNDP, FAO and UNEP are associated with this program. The objective of this program is to mitigate climate change through reducing net emmission of green house gases through enhanced forest management in developing countries. UN-REDD+Programme focuses on conservation and sustainable management of forests. It plays vital role in mitigating adverse effects of climate change. Proper design and effective implementation of UN-REDD+Programme can significantly contribute to protection of biodiversity and maintaining resilience of forest ecosystem. It also provides technical and financial support to developing countries thus contributing to poverty alleviation.



  • Brahmani and Vaitarni rivers merge at Bhitarkanika before emptying into the sea. Bhitarkanika is protected area for wildlife and bio-diversity. Brahmani River is known as South Koel in Jharkhand. The Brahmani River is formed by the confluence of South Koel and Sankh Rivers near Rourkela. Vaitarni River originates from Guptaganga hills in Keonjhan district of Orissa.

  • Created in 1948, the International Union for Conservation of Nature and Natural Resources (IUCN) is a membership Union which provides public, private and non-governmental organizations with the knowledge and tools to enable human progress, economic development and nature’s conservation to take place together. It is not a part of United Nations. IUCN’s expertise and extensive network provides a solid foundation for a large and diverse portfolio of conservation projects around the world.

  • The Economics of Ecosystems and Biodiversity (TEEB) is a global initiative focused on “making values visible”. Its principal objective is a mainstream the values of biodiversity and ecosystem services into decision-making at all levels. It aims to achieve this goal by following a structured approach to valuation that helps decision makers recognize the wide range of benefits provided by ecosystems and biodiversity, demonstrate their values in economic terms and where appropriate, capture these values in decision making.

  • Cheetah was declared extinct in India in 1952. Recently the Supreme Court of India withheld the government’s plan to rehabilitate cheetah in India. Significantly the government had planned to introduce cheetah in a wildlife sanctuary in Madhya Pradesh from Namibia. Snow leopard’s habitat is found 3000-4500 meters above the sea level. Surveys held in Uttarakhand and Himachal Pradesh have confirmed the presence of Snow leopards in India. Black necked crane is the state bird of Jammu and Kashmir. Flying squirrels are found in India, Russia, Japan, China, Europe, Africa and North America. India is habitat to seven species of flying squirrel six of which are found in Himalaya region.

  • Hibernation or winter sleep refers to a state of inactivity among animals of plants spending winter in a dormant state. It is a level servival strategy designed to conserve energy when weather conditions are not favourable. This condition is observed among both types of animal cold blooded and warm blooded. Squirrels, bears and some bats resort to hibernation in winter when they do not find means to feed on. In this state, animal’s metabolism slows, it’s temperature plungs and breathing slows. To face this situation they feed heavily in summer and autumn, storing fat to survive in winter. Mammals like squirrels, must rats, mice and other rodents fall under this category of animals.

  • The red panda is territorial mammal. Its zoological name is Ailurus Fulgens. Red panda live in temperate climates, in deciduous and coniferous forests, usually with an understory of bamboo and hollow trees. This makes them a key species of these forests and indicates of forest health. They are found in the Himalayan region, in parts of Nepal, Bhutan, Myanmar and Arunachal Pradesh. Most of the red pandas of the world are found in China whereas the majority of the Indian red panda is found in Arunachal Pradesh. Slow Loris species are found in Bangaladesh, Cambodia, China north-eastern India (Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland and Tripura), Myanmar (including the Mergui Archipelago), Thailand and Vietnam (except the south).

  • The Montreux Record is a greater of wetland sites on the list of Wetlands of International Importance where changes in ecological character have occurred are occurring or are likely to occur as a result of technological developments, pollution or other human interference. It s maintained as part of the Ramsar list.



  • Wetlands prevent flooding by holding water much like a sponge. By doing so, wetlands help keep river levels normal and filter and purify the surface water. Wetlands accept water during flood and whenever water levels in high. When water level is low, wetlands slowly release water. Wetlands also release vegetative matters into rivers, which help feed fish in the rivers. Wetlands help to counter balance the human effect on rivers by rejuvenating them and surrounding ecosystems.

  • The shore of inland wetland of the country’s total geographical area under the category of wetland is 69.22% and 27.13% area is under Coastal wetland category while 3.64% is under low wetland (<2.25 ha) category. Gujarat (3474950), has the greatest share of wetlands. Andhra Pradesh is at second place.

  • The International Treaty on Plant Genetic Resources for Food and Agriculture (IT PGRFA) is popularly known as the International Seed Treaty. It is a comprehensive international agreement in harmony with the Convention on Biological Diversity. It aims at guaranteeing food security through the conservation, exchange and sustainable use of the world’s plant genetic resources for food and agriculture. The world’s Heritage Convention and the United Nations Convention to Combat Desertification also has a bearing on the biodiversity.

  • Biomass is a term for all organic materials that stem from plants (including algae, tree and crops). Biomass is produced by green plants converting sunlight into plant material through photosynthesis and includes all land and water based vegetation as well s organic wastes. Hence deep sea has minimum biomass production. Highest biomass production if found among tropical rain forest. It is approximately 2200 gram/square meter/per year. Bio-mass production for bioms –

Deciduous forest – 1200 gram (dry weight)/square meter/every year

Taiga         –        800 gram (dry weight)/square meter/every year

Prairie       –        600 gram (dry weight)/square meter/every year

Deep Sea   –        Negligible gram (dry weight)/square meter/every year




Greenhouse Effect and Climate Change

  • Greenhouse gases and Pollutions are directly responsible for Ozone depletion while depletion of Ozone layer is indirectly responsible for climate change.

  • The main reason of climate change is the emission of greenhouse gases (a gas that contributes to the greenhouse effect by absorbing infrared radiation e.g. carbon dioxide and chlorofluro carbons, which are the main causes of the depletion of ozone layer. This ozone layer prevents most harmful ultraviolet light (UV) from passing through the earth’s atmosphere. Pollution due to human activity is also a prime reason for climate change.

  • The greenhouse effect is a natural process that warms the earth’s surface. When the sun’s energy reaches the earth’s atmosphere some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases. Greenhouse gases include water vapor, carbon dioxide, methane, nitrous oxide, ozone and some artificial chemicals such as chlorofluorocarbon (CFC). The absorbed energy warms the atmosphere and the surface of the earth, popularly known as greenhouse effect.

  • The concept of Greenhouse Gases was postulated by Joseph Fourier in 1824.

  • The Kyoto Protocol was adopted in Kyoto on 11 December, 1997, and entered into force on 16 February, 2005. The Kyoto Protocol is an international agreement linked to the United Nations Framework Convention on Climate Change. The global warming potential (GWP) of a gas depends on the efficiency of the atoms of that gas and it’s environmental life-cycle. The environmental life cycle of carbon di-oxide is changeable while it’s global warming potential remain constant (WGP=1). The global warming potential of Methane was observed 72 in last twenty years. Therefore Methane is more dangerous and effective as a green house gas than carbon di-oxide.

  • Greenhouse effect is the result of absorption of infrared radiation by environmental gases. Main green house gases are carbon dioxide, methane, nitrous oxide and chlorofluorocarbon.

  • Greenhouse gas in an atmosphere is a gas that absorbs and emits radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect. The primary greenhouse gases in earth’s atmosphere are carbon dioxide, methane, nitrous oxide and ozone.




  • The six major gases identified as Greenhouse Gases by Intergovernmental Panel on climate change include CH4, CFC and N2 The gases directly responsible for green house effect are –

  • Carbon dioxide (CO2)

  • Methane (CH4)

  • Nitrous Oxide (N2O)

  • CFC

  • SF6

  • NF3


While the gases indirectly responsible for green house effect include –

  • Nitrogen oxide (NOx)

  • Carbon monoxide (CO)

  • Non methane volatile organic compounds (NMVOC)

  • sulphur dioxide (SO2)



  • The contribution of gases in Greenhouse Effect

Water Vapor      –        36-72%

Carbon Dioxide –        9-26%

Methane             –        4-9%

Ozone                 –        3-7%

  • A layer of greenhouse gases mainly carbon dioxide, methane and nitrous oxide acts as a thermal blanket for the earth, absorbing heat and warming the surface known as global warming.

  • Plants use carbon dioxide to produce carbohydrates (sugars and starches) in the process known as photosynthesis. Since humans and all other animals depend on plants for their food, photosynthesis is necessary for the survival of all life on Earth. It is also greenhouse gas which is very harmful to us. Therefore carbon dioxide is both useful as well as harmful to like on earth.

  • According to the latest data available in 2014, largest contributor to carbon dioxide emission is china. It emits 30% of the world’s total carbon emission. United States is at second place with 15% and European Union is at third place with 9%. India is at fourth place with 7% and Russia is at fifth place in terms of carbon emission with 5% of the world’s total CO2

  • Chlorofluorocarbon is a mad-made gaseous and liquefied material made from carbon, chlorine, fluorine and oxygen which is used as a refrigerant in refrigerators and air-conditioned devices. Chlorofluorocarbon is an important factor of ozone depletion in the atmosphere.

  • As a result of global warming, glaciers are melting worldwide. Species that depend on one another may become out of sync. For example plants could bloom earlier than their pollinating insects become active. Global warming would of health risks include I. Direct-acting effects II. Impacts mediated via climate-related changes in ecological systems and relationship (e.g. field, mosquito ecology, marine, productivity).

  • Global warming is primarily a problem of too much carbon dioxide in the atmosphere. This carbon overload is caused mainly then we burn fossil fuels like coal, oil and gas or cut down and burn forests. The presence of carbon dioxide in the atmosphere was 315 PPM. If the increase of carbon dioxide continues in the atmosphere at this speed, it will reach approximately 650-950 PPM by the end of the 21st This will raise the earth’s temperature by 60 C.

  • Arctic and Green Land ice sheet are the most fragile eco-system that will be first affected by global warming. The melting of ice in this area will also affect entire earth.

  • The molecules of carbon dioxide in the atmosphere can absorb 90% of the infrared radiation received from Sun in the form of solar energy. This ability to absorb and re-emit infrared energy is what makes carbon dioxide an effective heat-trapping greenhouse gas. In recent years, however, excess emissions of carbon dioxide from human activities (mostly burning fossil fuels) have begun to warm earth’s climate at a problematic rate.



  • Earth Hour is worldwide movement for the planet organized by the World Wide Fund for Nature (WWF). The event is held worldwide annually encouraging individuals, communities, households and businesses to turn off their non-essential lights for one hour, 30 to 9.30 p.m. towards the end of March, as a symbol of their commitment to the planet. It was famously started as a lights-off event in Sydney, Australia in 2007. Earth Hour 2018 was observed on 24 March.

  • The United Nations Framework Convention on Climate Change (UNFCCC) was negotiate at the Earth Summit in Rio de Janeiro from 3 to 14 June, 1992, and entered into force on 21 March, 1994. Currently is has been ratified by 197 countries.

  • Agricultural is most affected by climate change. Changes in climate may also impact the water availability and water needs for agriculture. Due to increase in temperature the humidity of soil and it’s productivity is affected. It also raises salinity of soil and reduces productivity.

  • Methane (CH4) is also called Marsh Gas whose source is biogas, bacterial decomposition and cud-chewing animals. This is a greenhouse gas which pollutes the air.

  • The Greenhouse Gas Protocol (GHG Protocol) is the most widely used international accounting tool for Government and business leaders to understand, quantify and manage greenhouse gas emission. A decade-long partnership between the World Resource Institute (WRI) and the World Business Council for sustainable development, the GHG Protocol is working with businesses, governments and environmental groups around the world to build a new generation of credible and effective programs for tackling climate change.

  • A historic agreement to combat climate change and unleash actions an investment towards a how carbon, resilient and sustainable future was agreed by  194 nations at UNFCCC (United Nations  Framework Convention on Climate  Change)  in Paris on 12 December,  The universal agreement’s main aim is to keep global temperature rise this century well below 2 degrees Celsius and to drive efforts to limit the temperature increase even further to 1.5 degrees Celsius above pre-industrial levels. Governments decided that they will work to define a clear roadmap on raising climate finance to USD 100 billion by 2020.

  • The Global Atmosphere Watch (GAW) program of the World Meteorological Organization (WMO) promotes systematic and reliable observation of the global atmospheric environment.  Currently GAW coordinates activities and Data from 31 global stations, but at present in India, there is no GAW station.



  • The Clean Development Mechanism (CDM), defined in Article 12 of the Protocol, allows a country with an emission-reduction of emission limitation commitment under the Kyoto Protocol (Annex B Party) to implement an emission-reduction project in developing countries. Such projects can earn saleable certified emission reduction (CER) credits, each equivalent to one ton of CO2, which can be counted towards meeting Kyoto targets. The CDM was intended to meet two objectives:

  1. To assist parties not included in Annex I in achieving sustainable development and in contributing to the ultimate objective of the United Nations Framework Convention on Climate  Change (UNFCCC), which is to prevent dangerous climate change; and

  2. To assist parties included in Annex I in achieving compliance with their quantified emission limitation and reduction commitments (greenhouse gas (GHG) emission caps).

“Annex I” parties are the countries listed in Annex I of the treaty, the industrialized countries. Non-Annex I parties are developing countries. Thus projects under clean Development Mechanism are related to “Annex I” and ‘non-Annex I” countries.

  • Annex-I countries participated in the 1st Kyoto protocol. 37 Annex-I countries and the EU agreed to second-round Kyoto targets. Certified Emission Reductions (CER) are a type of emissions unit (or carbon credits) issued by the Clean Development Mechanism (CDM), Executive Board for emission reduction achieved by CDM projects and verified by a DOE (Designated Operational                                                                                           Entity) under the rules of the Kyoto  Cartagena Protocol is a supplementary protocol of conventional on Biological Diversity (CBD). It is committed to preserving bi-diversity from live Modified organisms-LMO caused by adoption of bio-technology. Cartagena protocol was adopted on 29 January, 2000. It came into effect on 11 September, 2003. Nagoya Protocol came into effect on 12 October, 2014. It is also supplementary protocol of CBD. It is concerned with access to genetic resources and fair distribution of benefits from them.

  • Carbon sequestration is the process of capturing and storing atmospheric carbon in plants, geologic structures and sea. In the context of mitigating the impeding global warming due to anthropogenic emissions of carbon dioxide, abandoned and uneconomical coal seams, depleted oil and gas reservoirs, and subterranean deep saline formations could be the potential sites for carbon sequestration.

  • The Bio Carbon Fund Initiative for Sustainable Forest Landscapes (ISFL) is a multilateral fund, supported by donor Governments ad managed by the World Bank. Norway has committed maximum $135 million, UK $120 million and USA $25 million for this fund. This fund seeks to promote reduction in Green house gases from land sector.



  • The Climate and Clean Air Coalition (CCAC) is a voluntary partnership of governments, inter-governmental organizations, business, scientific institutions and civil society organizations committed to improving air quality and protecting the climate through actions to reduce short-lived climate pollutants. It is a coalition formed by 53 countries and various institutions. CCAC mainly focuses on methane, black carbon and hydrofluorocarbons (HFCs). Along with spreading awareness about the effects of short-lived climate pollutants, the coalition also works for its mitigation strategy and to promote new operations at the regional and national level. Along with this, the allies of the coalition also recognize the fact that minimizations of short-lived climate pollutant is capable of working as supplementary and supplement in global efforts to minimize carbon dioxide.

  • The Forest Carbon Partnership Facility (FCPF) is a World Bank program which was established in 2008 and consists of a Readiness Fund and a Carbon Fund. The FCPF was created to assist developing countries to reduce emissions from deforestation and forest degradation, enhance and conserve forest carbon stocks and sustainably manage forests (REDD+) by providing value to standing forests.

  • If phytoplankton of an ocean is completely destroyed for some reason then the ocean as a carbon sink would be adversely affected. Phytoplankton, also known as microalgae are similar to terrestrial plants in that they contain chlorophyll and require sunlight to live and grow. Hence food chains in the ocean would be adversely affected and if it is completely destroyed then the density of ocean water would not decrease drastically.

  • Average increase in earth’s temperature during last century was 0.80

  • Astronomical theory of climate change was propounded in 1920 by astronomer Milutin Milutin Milankovic. It states that the variation in eccentricity, axial tilt and precession of the Earth’s orbit determines climatic patterns on Earth through orbital forcing. Hence, solar irradiance is not concerned with this theory.

  • There are two primary causes of climate change- factors that increase carbon emission and factors that increase carbon absorption. The cause of increases in carbon emission include excessive burning of fossil fuels, exploding numbers of automobiles driven by oil etc., while the carbon absorption rate is declining due to excessive deforestation. Therefore carbon concentrations are increasing in the atmosphere which is affecting the climate by increasing green house effect. NASA and other studies do not consider the solar flare as a major cause of climate change.



  • The GCCA was established by the European Union (EU) in 2007 to strength dialogue and cooperation with developing countries, in particular least developed countries (LDCs) and small Island developing states (SIDS). It started its work in just 4 countries. Today it has a budget of more than x300 million and is one of the most significant climate initiatives in the world. It supports 51 programmes around the world and is active in 38 countries, 8 regions and sub regions and at the global level. It completes its goal through two interactive strong pillars. These include providing technical and financial assistance to targeted developing countries for the integration of climate change in their development policies and budgets. The overall aim of GCCA is to create a new treaty between the European Union and the poor developing countries, who have the least potential to deal with climate change. It is coordinated by the European Commission (EC).

  • India’s first National Action Plan on climate change was released in June, 2008 by the then Prime Minister Manmohan Singh.

  • Climate Action Plan of Government of India was launched on 30 June, 2008. Eight National Mission under this Action plan are as below:

  1. National Solar Mission

  2. National Mission for Enhanced Energy Efficiency

  3. National Mission on Sustainable Habitat

  4. National Water Mission

  5. National Mission for Sustaining the Himalaya Ecosystem

  6. National Mission for Green India

  7. National Mission for Sustainable Agriculture

  8. National Mission on Strategic Knowledge for Climate Change

  • Supported by UNDP, the state government of Jharkhand initiated process to develop Jharkhand Action Plan on Climate Change. On May, 2011 the state steering Group and State Advisory Group (SAG) were formed through state government notification. The Department of Environment and Forests led the preparation of JAPCC in consultation with various departments. On 23rd December 2013 final public consultation meeting was organized at Jamshedpur for sharing of draft. JAPCC shared it with concerned departments and general public for comments and feedback. JAPCC endeavors reframing development pathways with low carbon growth, at the same time ensuring that development opportunities are protected, supported and increased.

  • According to Jharkhand Plan on Climate Change Report (2014) Saraikela Kharsawan is the most sensitive district with the score of 0.78 which shows its vulnerability. The measurement it prepare on the scale of (-1) to (+1), which shows respective vulnerability.

  • Scientists of Manchester University have suggested using sea water for creating brightening clouds for maximum reflection of sun rays. This will help controlling global warming.

  • Any method which help the soil to retain more organic matter so that it may work as an effective Carbon sink would be helpful in Carbon sequestration or storage. Contour bunding is one of the extensively used soil and water conservation technique in several rained areas. Contour bunding is a Mechanical measure which minimizes the soil erosion.

  • Relay cropping means that a new crop is planted or sown before the previous one is harvested. This can provide advantages for both crops as one of them may provide nitrogen benefit of Relay cropping is soil conservation.

  • Zero tillage is also based on the premise of soil conservation, the basic premise is to minimize the disturbances to the soil leading to an increase in retention of water, nutrients and topsoil itself. Zero tillage has carbon sequestration potential through storage of soil organic matter in the soil of crop fields.   

  • Countries of the world adopted a historic international climate agreement at the U.N. framework convention on climate change conference of parties (COP21) in Paris in December 2015. Countries publicly outlined post-2020 climate action they intended to take under this agreement. This was known as Intended Nationally Determined Contribution (INDCs).



INDC of India

  • Reduction in the emissions intensity of its GDP by 33 to 35 percent by 2030 from 2005 level.

  • Attain 40 percent non-fossil based power capacity by 2030

  • Create an additional carbon sink of 2.5 to 3 billion tones of CO2 through additional forest and tree cover by 2030

  • Climatic adaptation and path of clean for economic growth

  • Green Climate Fund (GFC) was founded as a mechanism to assist developing countries in adaptation and mitigation practices to counter climate change. The fund is governed by GCF board. The board consists of 24 members.

  • A carbon tax is a fee intended to make users of fossil fuels pay for climate damage by their fuel use whereas Sweden, Finland, the Netherland and Norway have already introduced Carbon Tax. New Zealand, in 2015 introduced for the first time, carbon tax to address global warming.

  • The population of Asia Pacific Partnership countries is 41% of world’s population. They consume the world’s 48% of energy and contribute nearby 48% of the world’s greenhouse gases. They intended to support the Kyoto Protocol however some of the countries have not ratified it.



Ozone Layer

  • The earth’s atmosphere is divided into several layers and each layer plays an important role. The layer extending about 10-15 km is called the stratosphere. The ozone layer is mainly found in the lower portion of the stratosphere from approximately 20 to 35 km above the Earth, though the thickness varies seasonally and geographically. The ozone layer protects the Earth from the sun UV rays. 10% of the ozone layer is found in troposphere and 90% in stratosphere.

  • The lowest region on the atmosphere is called troposphere. The thickness of the troposphere is maximum at equator, deepest in the tropics up to 18 to 20 km and shallowest near the polar region. After this come the stratosphere, mesosphere, thermosphere and exosphere respectively.

  • Chlorofluorocarbon is an organic compound that contains carbon, chlorine and fluorine. One of the elements that make CFC is chlorine. Under certain conditions, this chlorine has the potential to destroy a large amount of ozone. Hence it is one of the major causes of the greenhouse effect.

  • Ozone (O3) is a molecule formed by three atoms of oxygen. While O2, which we normally refer to as oxygen, is essential for all aerobic forms of life. Ozone is a deadly poison. However, at the higher levels of the atmosphere, ozone performs an essential function. It shields the surface of the Earth from ultraviolet (UV) radiation from the Sun. This radiation highly damaging to organisms and is known to cause skin cancer in human beings.

  • The Ultraviolet rays of the sun are categorized as UV-A, UV-B and UV-C. First two types of ultraviolet rays are harmful to skin. UV-C is extremely dangerous however is does not reach the earth surface. The effect of UV-B on organism is as follow:

UV-B effect of radiation

  • Gene Mutation

  • Genetic Defects

  • Hindrance in the growth of plants

  • Skin cancer

  • Cataracts

  • Sunburn

  • Weakening of the immune system

  • Harm to leaves

  • In 1994, the UN General Assembly proclaimed 16 September as the International Day for the Preservation of the Ozone Layer, commemorating the date of the signing, in 1987, of the Montreal Protocol on Substances that deplete the Ozone Layer. The theme of 2017 was “Caring for all life under the sun”.

  • Ozone layer in the atmosphere prevents harmful ultraviolet rays from reaching the Earth’s surface. It thus safeguards life on Earth. Gases responsible for depletion of ozone layer are- CFC, Halon- 1211, 1301, Nitrous oxide and Trichloroethylene etc.

  • The greenhouses gases responsible for ozone depletion in troposphere are – Water Vapor, Carbon dioxide, Methane, Ozone, Nitrous oxide and Chlorofluorocarbon.

  • The ozone hole is not technically a “hole” where no ozone is present, but is a region of exceptionally depleted ozone in the stratosphere over the Antarctic that happens at the beginning of Southern Hemisphere spring.



  • The Montreal Protocol on substances that deplete the Ozone Layer (a protocol to the Vienna Convention for the Protection of the Ozone Layer) is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion. It entered into force on 1 January, 1989.

  • Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine and fluorine. They are used in the manufacture of aerosol sprays, blowing agents for foams and packing materials, as solvents, and as refrigerants. Trichlorofluoromethane can dissolve grease and used to clean electronic equipment. It is a highly stable compound and can sustain in the atmosphere for 80 to 100 years.

  • Nitric Acid in the Polar stratosphere clouds reacts with chlorofluorocarbon. This reaction produces chlorine which is responsible for photo-chemical destruction of ozone layer. Since stratospheric clouds help chlorine compound to convert in chlorine parties depleting Ozone layer, their presence is also a factor responsible for formation of ozone hole.

  • The gases filled in the refrigerator are sold as Mafron. These gases are commonly helonic hydrocarbon. Although Amonia is also used as coolant in big plants.

  • British team first discovered ozone hole over Antarctic in 1985 using “total ozone mapping spectrometer”.

  • In the leadership of G.W. Kent Moore, University of Toronto, in 2005, the researchers discovered Ozone halo over Tibetan Plateau.

  • The ozone layer is a layer in Earth’s atmosphere which contains relatively high concentrations of ozone (O3). This layer absorbs 93-99% of the sun’s high-frequency ultraviolet light, which is potentially damaging to life on Earth.



Forest and Forest Wildlife

  • The tropical evergreen forests are found in areas receiving more than 200 cm of rainfall and having a temperature of 15 to 30 degrees Celsius. They occupy about seven percent of the Earth’s land surface and harbour more than half of the world’s plants and animals. They are found mostly near the equator. In India, evergreen forests are found on the Western Ghats, north east India and Andaman and Nicobar Islands.

  • Equatorials forests are founded in such temperature zones which receive more than 20 cm rainfall. Tall, closely set trees forming canopy is a characteristic of these forests. The upper portion of canopy often supports rich epiphytes. About 80% of world’s bio-diversity is found in equatorial forests.

  • As per National Forest Policy, 1988 the national goal should be to have a minimum of one-third (33%) of the total land area of the country under forest or tree cover. In the mountain and hills region, the aim should be to maintain two-third of the area under such cover to prevent erosion and land degradation and to ensure the stability of the fragile ecosystem.

  • According to National Forest Policy (1952) forests have been classified in India as follows:

  1. Protected forests

  2. National forests

  3. Village forests

  4. Tree-lands

  • Urbanisation is not the effect of deforestation rather it is one of the reasons of deforestation. The expansion of residential areas to meet the needs of growing population impacts forests and bi-diversity. Forest areas have shrunk due to the expansion of towns and cities. On the contrary, drying of water resources in Himalayas, loss of bio –diversity and soil erosion are the effects of deforestation

Impact of deforestation

  • Less rain

  • Impact on regional and global climate

  • Drying up of water sources in the Himalayas

  • Species extinction

  • Increase in global warming

  • Flood and drought

  • Harm to Biodiversity

  • Formation of desert

  • Soil erosion

  • Decrease in soil fertility

  • One of the 8 missions outlined under the National Action Plan on climate change (NAPCC), National Mission for Green India (GIM) acknowledges the influence of forests on environmental amelioration through climate change mitigation, water security, food security, biodiversity conservation and livelihood security of forest-dependent communities. In the second sitting of National Executive Council (NEC) of National Mission for Green India (GIM) held in October, 2015 the annual plan for the possible schemes and operation proposed by the four states- Mizoram, Manipur, Kerala and Jharkhand was approved.

  • On the basis of the development stage, natural resources are categorized are:

  1. Potential Resources

  2. Actual Resources

  3. Reserve Resources

  4. Stock Resources

Potential Resources are those which exist in a particular area and can be used in future. Actual Resources are those which have been surveyed and their valume and quality has been determined and these are being used currently. The development of an actual resource depends upon technology and cost of production.



  • Chorao Island of Goa is a protected mangrove region.

  • Mangrove Forest, Evergreen Forest and Deciduous Forests, all are found in Andaman and Nicobar Island. IFSR, 2015 Andaman & Nicobar covers 617 sq. km of mangrove forest.

  • A mangrove commonly refers to two different things: a tidal swamp ecosystem found in tropical deltas, estuaries, lagoons or islands and the characteristics tree species populating this ecosystem. Mangrove trees have developed unique adaption to the harsh condition of coastal environments. Most of the region of Mangrove plants are found in Sundarban delta. Sundari plant in these forests is quite popular.

  • Nagaland Mountains are becoming increasingly barren mountains mainly due to shifting cultivation.

  • The wildlife (Protection) Act, 1972 is for the protection of wild animals in India.

  • “Apna Van Apna dhan” scheme has been started by Himachal Pradesh government. The scheme aims to promote afforestation.

  • The first comprehensive legislation relating to the protection of wildlife was passed by the Parliament and it was assented to by the President on 9th September, 1972 and came to be known as The Wild Life (Protection) Act, 1972.

  • According to the Wildlife (Protection) Act, 1972 Gharial, Indian wild ass and wild buffalo all the three animals cannot be hunted by any person except under some provisions provided by law.

  • The Forest (Conservation) Act 1980 was enacted on 27 December, 1980.

  • Tropical moist deciduous forests are found in areas of moderate rainfall of 100 to 200 cm per annum. The trees of these forests drop their leaves for about 6-8 weeks during the spring and early summer when sufficient moisture for the leaves is not available. Teak trees are most dominant species of trees found in these forests. Bamboos, sal, shisham, sandalwood, khair, Kusum, Arjun, mulberry are some of the other commercially important species found here.

  • The greatest diversity of plants and animals is found in tropical moist forests.



  • National Bureau of Plant Genetic Resources was established in January, 1977. It has its headquarters in New Delhi. The Organization works as a nodal agency for activities of plant introduction and germplasm augmentation for use in crop improvement. It has ten regional stations across the country.

  1. Shimla

  2. Jodhpur

  3. Trisur

  4. Akola

  5. Shilong

  6. Bhovati

  7. Katak

  8. Hyderabad

  9. Ranchi

  10. Srinagar

  • The Rajiv Gandhi Wild Life Conservation Award is given annually for significant contribution in the field of wildlife conservation which has made or has the potential to make, a major impact on the protection and conservation of wildlife in the country. Two awards of Rupees One lakh were given to education and research institutions, organization, forests and wildlife officers/research scholars or scientific/wildlife conservationists.

  • Pugmark is the term used to refer to the footprint of most animals (especially megafauna). “Pug” means foot in Hindi. Every individual animal species has a distinct pugmark and as such this is used for identification.

  • Chandi Prasad Bhatt was the protagonist of the Chipko Movement. He established “Dasoli Gram Swaraj Mandal” in 1964. This institute later became the base of Chipko Movement. Chipko movement started in 1973 against large scale cutting of forests. Sundarlal Bahuguna also played leading role in this movement. Chandi Prasad Bhatt also received Ramon Magsaysay award in 1982.

  • Chipko movement was an organized movement against the destruction of forests during 1970. Sundarlal Bahuguna was the leader of this movement.

  • World Wildlife Day is celebrated on different dates in different countries. In America it is celebrated on December 4, in India Wild Life week is celebrated from 2-8 October. World Environment Day on June 5 while World Forest Day is celebrated on March 21. In the 16th (CoP 16) meeting of parties to the Convention of International Trade is Endangered Species (CITES) held in Bangkok in March, 2013, a proposal was placed to declared March 3rd as World Wildlife Day. On December 20, 2013 in its 68th annual session. United Nations General Assembly decided to celebrate March 3rd as World Wildlife Day.

  • In 1974, the Forest Department auctioned approximately 680 hectares of forest in Raini Village of Joshimath. Then under the leadership of Gaura Devi, hundreds of women opposed the deforestation by sticking to the trees.

  • Whale Shark is the largest fish not only of India but the world. It may be up to 50 m long. They live on the coasts of Australia and South Africa but every year in March they use to come to the coasts of Gujarat. This time is gestation of Whale Sharks. A program was started 2004 for the protection of Whale Sharks coming to the coasts of Gujarat.

  • The main cause for the forest loss is industrialization. Deforestation occurs due to the urbanization and empty land is being used for agriculture purpose.



Causes of deforestation

  • Forest Fire

  • Ignoring sustainable development in policy making

  • Expansion of agricultural land

  • Development of roads

  • Urbanization

  • Industrialization

  • Indiscriminate commercial use of plants

  • Grazing by cattle

  • The Amazon also known as Amazonia or the Amazon Jungle, is a moist broadleaf forest that covers most of the Amazon basin of South America. The Amazon rainforest functions as a giant air machine that absorbs a large amount of carbon dioxide and produces oxygen. That is why it is often called the “Lungs of the Earth” It is estimated that the Amazon rainforest produces more than 20 percent of world’s oxygen.

  • Tropical deciduous forests or tropical broad-leaf forests are dominated by trees that lost their leaves each year. They are found in areas with warm, moist summers and mild winters. These forests are mainly found in the Northern Hemisphere Eastern North America, East Asia, and Europe.



  • The National Forest Policy 1988 includes –

  1. Afforestation and Wasteland development

  2. Reforestation and replantation in existing forests

  3. Encouraging wood substitute and supplying other types of fuel

  • Pterocarpus santalinus with the common name red sanders is a species of Pterocarpus endemic found in the southern Eastern Ghats mountain range of South India. This tree is valued for the rich red colour of its wood. Red Sanders grow on the Palkonda and Sechachalam mountain range in Andhra Pradesh.

  • Forestation of one-third to total country’s land and encouragement of public community participation in forest management are main objectives of National Forest Policy.

  • Valparai is located in Coimbatore district of Tamil Nadu.

  • The government of Bhutan has passed resolution to maintain forest on 60% land of its total geographical area. Presently around 72% of its territory is covered with forests.

  • Aluminium is known as green metal due to its eco-friendly and renewable specialties. In no way aluminium can substitute wood.

  • Mangroves can serve as a reliable safety hedge against coastal calamities. The mangrove trees do not get uprooted by storms and tides because of their extensive roots.

  • Trade Related Analysis of Fauna and Flora in Commerce (TRAFFIC) is a non-government organization. It serves to monitor the trade to wild plants and animals in context of sustainable development and biodiversity conservation. The mission of TRAFFIC is to ensure that the trade of wild plants and animals does not threaten the conservation of nature. TRAFFIC was established in 1976. It is a strategic alliance of WWF and IUCN. It is not a bureau under UNEP.

  • The Taxus tree is naturally found in the Himalayas. The Taxus tree is listed in the Red Data Book. A drug called Taxol is obtained from Taxus tree which is used in breast and lung cancer treatment and also effective against Parkinson’s disease.

  • The Animal Welfare Board of India is a statutory advisory body on animal Welfare laws and promotes animal welfare in the country, established in 1962 under Section 4 of the Prevention of Cruelty to Animals Act, 1960. National Tiger Conservation Authority is Statutory Body under the Ministry of Environment, Forests and Climate Change (Government of India). The National Ganga River Basin Authority was set up on 20 February, 2009. This authority is chaired by the Prime Minister and has its members the Union Ministers concerned, the Chief Ministers of States through which Ganga flows.

  • In Uttarakhand, the Oak-Rhododendron are characteristics plants found in temperate forests. The temperate zone is marked by the presence of Quercus leucotrichophoro (Banj Oak), Rhododendron arboretum (Burans), Myrica esculent (Kaphal), Leonia ovalifolia (Aynor), Ibex dipyrena, Quercus semecarpifolia (Kharsu oak) etc.

  • The first World Tiger Summit was held in 2010 between 21 to 24 November at Saint Petersburg (Russia).



  • As a part of wildlife conservation efforts in Nepal and India, a new association by the name “SAVE” was launched recently. The objective of SAVE is to conserve tigers. Tibetan Buddhists use tiger skin for decoration and as seat while offering prayers which results in an increase tiger hunting cases. India and Nepal jointly formed an organization named “SAVE” in July, 2010 for the conservation of tigers. It also has the objective to work for increasing the number of tigers.

  • Kharai Camel or swimming Camels are funded only in Gujarat’s Bhuj area. It has been recently recognized as a separate breed (one among nine such breeds found in India) of camel for better conservation. It can swim up to three km into the sea in search of mangroves, its primary food. Kharai Camel can live in both coastal and dry ecosystem. Given the breed’s ability to survive both on land and sea, the Kharai camel is one of the most choices of graziers in the arid coastal region of Kachchh.

  • Gharial, Leatherback turtle and Swamp deer all of three come under the endangered category.



Sanctuaries/Biosphere Reserves

  • International Tiger Day is observed on July, 29 catching worldwide attention to the conservation of tigers. It is both an awareness day as well as celebration. It was founded at Saint Petersburg Tiger Summit in 2010.

  • A National Board for Wildlife (NBWL), chaired by the Prime Minister of India provides a policy framework for wildlife conservation in the country. A network of 773 Protected Area’s has been established extending over 160901.77 sq. km (4.9% of total geographic area), comprising 103 National Parks, 537 Wildlife Sanctuaries, 67 Conservation Reserves and 26 community Reserves. In India, most of the wildlife protected areas are surrounded by dense forests.

Benefits of Protocol Area

  • Protection of natural and allied cultural sources

  • Managing number of communities and there settlements

  • Conservation of all inhabitant species and sub-species

  • Facilitating rehabilitation of species in the event of climate change

  • Ban on rehabilitation of external species by humans

  • Conservation of genetic diversity of existing species



  • The Government of India has taken a pioneering initiative for conserving its national animal, the tiger, by launching the “Project Tiger” in 1973. The Project Tiger aims to save the tiger from extinction.

  • In 1982, Delhi Zoo was officially renamed to National Zoological Park, with hopes that it could become a model for other zoos in the country. Wikipedia in its article “Sightseeing in Delhi” termed the same part as National Biological Park. This could be the reason why it has been described as National Biological Garden. However in the official website of this garden in Hindi it is entitled as “Rashtriya Prani Udyn” and in English it is entitled as National Zoological Park”.

  • The term “M-STrIPES stands for monitoring system for Tigers-Intensive Protection and Ecological Status is sometimes seen in the news in the context to maintenance of  Tiger Reserves.

There are two main components of this mechanism –

  1. Field Based protocol for patrolling, law enforcement, recording wildlife crimes and ecological monitoring.

  2. Acustomized software for storage, retrieval, analysis and reporting. On proper implementations, it ensures quick response in the perilous conditions like tiger hunting or habitat destruction. It uses a system based on Geographical Information System (GIS).


National Park

Year of establishment

Jim Corbett (Uttarakhand)


Kanha (Madhya Pradesh)


Dudhwa (Uttar Pradesh)


Rajaji (Uttarakhand)






Silent Valley






  • Jim Corbett National Park, which is a part of the larger Corbett Tiger Reserve lies in the Nainital district of Uttarakhand. Established in the year 1936 as Hailey National Park, Corbett has the glory of being India’s oldest and most prestigious National Park.

  • Nagarhole forest (also called the Rajive Gandhi National Park) is one of the most popular tourist attractions of Coorg. Located in the districts of Mysore and Coorg, at a distance of 94 KM from the city of Mysore, Nagarhole is one of the best-managed parks of India.

  • Betla Nation al Park is located in the Chhota Nagpur Plateau of the Palamu district of the Indian State of Jharkhand, then Bihar, in India. It was established in 1986 and is associated with “Project Tiger”.

  • The Periyar Game Sanctuary is located in Kerala which is famous for wild elephants.

  • Rani Jhansi Maritime National Park was founded in 1996 at Andaman and Nicobar Island. The area of the park is spread over 256.14 sq km.

  • Gir National Park is located in Joonagarh, Gujarat. It is famous as the habitat of Asiatic lions. Besides, Sanbhan and Cheetal are also found in Gir National Park.

  • Nagarjun Sagar Sailam Tiger Reserve of Andhra Pradesh is largest tiger habitat in India. It is notable that after the reorganisation of the state, 3296.31 sq km area of this Reserve falls under Andhra Pradesh while 2611.39 sq km area falls under Telangana.



  • Total 18 biosphere reserves have been listed so far. These are –



5520 km2

Nanda Devi


5860.69 km2



820 km2

Great Nicobar



Gulf of Mannar


10500 km2



2837 km2



9630 km2



4374 km2



765 km2



5111.50 km2



4926 km2



2619.92 km2



1828 km2



3835.51 km2



12454 km2

 Cold Desert


7770 km2

Seshachalam Hills


4755.997 km2



2998.98 km2



  • Keoladeo Ghana National park formerly known as Bharatpur Bird Sanctuary is situated in Bharatpur, It is home to 366 bird species, 379 floral species and different species of fish, snakes, lizards and amphibians. However, lion is not a protected species of this park.

  • Biosphere reserves are areas comprising terrestrial, marine and coastal Each reserve promotes solutions reconciling the conservation of biodiversity with its sustainable use. The core area (S) comprises a strictly protected ecosystem that contributes to conservation of landscapes, ecosystems, species and genetic variation.

  • Ten of the eighteen biosphere reserves are a part of the World Network of Biosphere Reserves based on the UNESCO Man and the Biosphere (MAB) Programme list.

Name –

  1. Nilgiri Bisphere Reserve

  2. Gulf of Mannar Biosphere Reserve

  3. Sundarbans Biosphere Reserve

  4. Nanda Devi Biosphere Reserve

  5. Nokrek Biosphere Reserve

  6. Panchmarhi Biosphere Reserve

  7. Simlipal Biosphere Reserve

  8. Great Nicobar Biosphere Reserve

  9. Achanakmar-Amarkantak Biosphere Reserve

  10. Agasthyamala Biosphere Reserve



  • National Parks Animals

Bandipur            –        Tiger Reserve

Kaziranga           –        One horn Rhinoceros reserve

Sunderbans        –        Biosphere and Tiger Reserve

Simlipal             –        Elephant Reserve


Name of Tiger Reserve




Jim Corbett (buffer of Corbett TR)



Madhya Pradesh












West Bengal






West Bengal




Arunachal Pradesh


Uttar Pradesh


Tamil Nadu




Madhya Pradesh




Madhya Pradesh


Madhya Pradesh








Arunachal Pradesh




Madhya Pradesh


Tamil Nadu












Madhya Pradesh


Tamil Nadu







Biligiri Ranganatha Temple





Tamil Nadu

Mukandra Hills




Nagarjunsagar Srisailam Park

Andhra Pradesh




Uttar Pradesh



Rajaji Tiger Reserve


Orang Tiger Reserve


Kamlang Tiger Reserve

Arunachal Pradesh

Sanjay National Park

Madhya Pradesh

Dochigam National Park

Jammu and Kashmir

Papikonda National Park

Andhra Pradhesh

Sariska National Park


Bharatpur Bird Sanctuary


Indravati National Park


Gampani Sanctuary





Sanctuary/National Park

Main Protocol Animal









  • Yellowstone National Park is a located in the United States of America (USA) in the state of Wyoming, Montana and Idaho. It was established on March 1, 1872. The park is known for its wildlife and its many geothermal features, especially old Faithful Geyser. It is the first National Park of U.S.A.

  • Gulf of Mannar is a marine national park in Tamil Nadu, established in the year 1986.

  • Small scale photographs are suitable for wildlife management in Jim Corbett National Park situated at Uttarakhand and Rajaji National Park.

  • The Keibul Lamjao National Park is situated in Bishunpur district of Manipur. This National Park is characterized by many floating decomposed plant materials locally called phasmids.

  • Maharashtra has become the first state in the country to have a “State butterfly”. State Government has declared the Blue Mormon (Papilo Polyster) as the State Butterfly.

  • Sathyamangalam Tiger Reserve is located on the meeting site of Eastern Ghats and Western Ghats. Apart from tiger, elephant, hyena, leopard etc are also found in this tiger reserve. This is the largest wildlife sanctuary in Tamil Nadu. Nallamala forest is located in Andhra Pradesh. Nagarhole National Park is located in Karnataka. Sechachalam Biosphere Reserve is the first biosphere reserve of Andhra Pradesh.

  • The Pench tiger reserve is spread over two States namely Madhya Pradesh (90%) and Maharashtra (10%).

  • Initially UNESCO’s World Biosphere reserve list only included India’s Nilgiri, Sundarban, Bay of Mannar and Nanda Devi biosphere In my 2009 UNESCO announced to include 22 new Biosphere reserves of 17 countries. In the new list India’s Simlipal, Pachmadi and Nokrek biosphere reserves were also included. After that in July 2012, UNESCO also included India’s Achankamar Amarkantak biosphere reserve. In 2013, Great Nicobar biosphere reserve also become a part of this list. By March, 2016, UNESCO’s list included 669 Biosphere Reserve of 120 countries.

  • Launched in 1971, UNESCO’s man and the biosphere programme (MAB) is an intergovernmental scientific program that aims to establish a scientific basis for the improvement of relationship between people and their



  • The great Himalayan National Park (GHNP) is located in the Kullu district of Himachal Pradesh, Initially constituted in 1984, GHNP was formerly declared a national park in 1999, covering an area of 754.4 square km. In 1994, two major changes were made in land use around the park. A butterfly zone of 5 km from the park’s Western boundary, covering 265.6 Sq Km including 2300 household in 160 villages, was delineated as Ecozone. Most of the population (about 15000 to 16000 people) in the Ecozone is poor and dependent on nature on natural resources for their livelihoods. The great Himalayan National Park conservation area (GHNPCA) as a natural site was inscribed into the UNESCO World Heritage list during the session of 38th world heritage committee in Doha the state of Qatar, on 23rd June 2014.

  • Gulf of Mannar (10500 km2) is the largest biosphere reserve in term of area approved by However terms of area it is India’s second largest biosphere reserve. Largest biosphere in India is Runn of Kutch with total area of 12454 square km.

  • Nokrek National Park is located 2 km from Tura peak in West Garo Hills district of UNESCO added this Park to its list of Biosphere Reserve in may, 2009. Loktak lake is the largest freshwater lake of India. It is located in Manipur and is famous for the phumdis floating over it. Namdapha National Park is the largest protected area in the Eastern Himalayan biodiversity hotspot and is located in Himachal Pradesh.

  • Cold desert biosphere reserve located in Himachal Pradesh was on 28 August, 2009 declared as 16th Biosphere Reserve of On 20th September, 2010, Seshachalam Hills of Andhra Pradesh was declared as 17th Biosphere Reserve of India and 25th August, 2011, Panna (Madhya Pradesh) was declared as 18th Biosphere Reserve of India. Establishment of Biosphere Reserve help protecting biodiversity and achieve sustainable development. Below is the illustration of Biosphere Reserve play an important role in the environment.

  • The total estimated population of tigers in the world is 3000-4000. India is home of 2,226 wild tigers which is highest as compared to other countries in the world.

  • Kuno wildlife Sanctuary of Palpur-kuno wildlife sanctuary lies in the Sheopur district of Madhya Pra The Kuno wildlife sanctuary was selected as the reintroduction slide for the endangered Asiatic lion because it was home to acetic lion before they were hunted to extinction in about 1873.

  • Bhitarkanika national park has one of the largest populations of endangered saltwater crocodiles, in

  • Desert National Park is a beautiful place, located in the Jaisalmer district of the state of The Great Indian Bustard is a magnificent and can be seen considerably good numbers in this Park. Hoolak Gibbon is found in north eastern state of India mainly in Assam.



  • To see gharials in their natural habitat, Chambal river is the best place to the scientific name of gharials is ‘GavialisGnageticus’. The most of the Gharials in India are found in the chamble and Girwa river. IUCN has placed ghariyals in the category of critically endangered.

  • Dampa Tiger reserve, the largest wildlife sanctuary in Mizoram was notified in 1985 and declared Tiger Reserve in Gumti Wildlife Sanctuary is situated in Tripura. Saramati is a peak rising above the surrounding peaks at the mountainous border of Nagaland state, India and the Sagaing region of Burma.

  • Ram Ganga and Kosi river flows through Corbett National park but river Ganga does not flow through Corbett National Brahmaputra, Diphlu, and Mora Diphlu and Mora Dhansiri are the rivers which flows through Kaziranga National Park. Kunthipuzha river flow through Silent Valley National Park.

  • Harike wetland is located Downstream the Confluence of the Vyas and Satluj rivers .Keoladeo Ghana National Park is located at the confluence of two Rivers, the Gambhir and Kolleru lake is one of the largest fresh water lakes in India in Andhra Pradesh. Between Krishna and Godavari deltas.

  • Marine National Park in the Gulf of Kutch is situated on the Southern Shore of the Gulf of There are 42 Island on the Jamnagar coast in the Marine National Park, most of them surrounded by reefs. 52 Coral species, mollusks, dolphin, tortoise and various kinds of sea birds found here.

  • Chinar Wildlife Sanctuary is situated in Kerala.

  • Sultanpur Bird Sanctuary is situated in Gurgaon, Haryana.

  • The Cloud Goats of Nilgiri are found in Eravikulam National Park. They are rare species and called as Nilgiri Tahr.

  • Bir Sanctuary of Tamil Nadu is located in Karikili. It is 40 km away from Chennai.

  • In Bhutan, National Parks spread over 12922 sq. km which is 33.66% of the total geographical area of the country.

  • World’s largest botanical garden – Royal Botanical Garden is located in Kew, England. It was formed in 1759 and declared a world heritage site by UNESCO in 2003. It is habitat to more than 40 thousand floral species.

  • Bundala Biosphere Reserve is located on the south east coast of Sri Lanka. It is an international wintering ground for migratory birds. In 2005, it was designated as a biosphere reserve and included in Man and Biosphere Reserve Network by UNESCO.



Non-Conventional Energy

  • Solar energy is used most in organic form. Light and heat from the Sun are essential for life on Earth. Solar energy is required for the process of photosynthesis is plants. Photovoltaic systems convert sun rays into the solar heat.

Other uses of Solar Energy

  • Sun Therapy

  • Photosynthesis

  • Water heating

  • Solar cooker

  • Artificial satellite (Mangalyan)

  • Electricity generation by solar plant

  • Solar equipment

  • Transportation

  • Fossil fuels are non-renewable sources of energy. Fossil fuel was formed by natural processes through decomposition of buried organism. Examples of fossil fuel include oil, coal and natural gas. Fossil fuels are the main sources of energy presently.

  • Solar energy is a unique source of which is pollution free and does not give rise to environmental issue.

  • The danger of extinction of fossil fuels like coal and crude oil is called energy crises.

  • Sustainable development is economic development that is conducted without depletion of natural resources. Coal, Mineral Oil, gas and atomic energy are natural resources which are limited. Hydroelectricity uses water to produce electricity without depleting water. Hence Hydro-electricity is the best source to generate electricity for sustainable development.

  • Diesel, Coal and Kerosene, when comes in contact with atmospheric oxygen, produce carbon dioxide, a greenhouse gas which is a major factor for pollution. On the other hand hydrogen, when comes in contact with oxygen, forms water and produces a huge amount of energy. Thus it, is highly efficient fuel with minimum pollution. Notably, India has set a target generate 1000 MW electricity through hydrogen based technology.

  • The solar power source of renewable energy has the greatest potential in The role of new and renewable energy has been assuming increasing significance in recent times with the growing concern for the country’s energy security. Solar panel the most eco friendly power generation system. They are called as the fuel of the future. This is why, the government has set a target of 20,000 megawatt solar power generation by 2022 under Jawaharlal Nehru Solar Mission started on 11 January 2010. It is to be noted that world’s largest Solar plant has been established in Tamil Nadu .

  • Biofuel development in India centres mainly around the cultivation and processing of jatropha plant seed which are very rich in oil. jatropha oil can be used after extraction in diesel generator and engines . Jatropha oil has been used in India for several decades as biodiesel for the fuel requirements  of the remote ruler  and forest

  • During the establishment of nuclear power projects, radioactive radiation and radioactive waste disposal is to be taken into consideration. Radioactive radiation would have a disastrous effect on flora and fauna.




  • Pollution occurs as a result of unexpected change in physical, chemical and biological characteristics of soil, water and air. It occurs due to concentration of pollutants. Pollution is of different kinds. It can be categorised as –

Types of Pollution

Depending on the parts of environment

  • Air Pollution

  • Water Pollution

  • Land Pollution

On the basis of physical properties

  • Gaseous Pollution

  • Dust Pollution

  • Thermal Pollution

  • Noise Pollution

  • Radio Active Pollution

On the basis of origin

  • Natural –        Eruption of volcano

  • Anthropogenic –        Anthropogenic industrial and agricultural pollution

On the basis of ecosystem

  • Biodegradable –        House waste, animal excreta sewage

  • Non-biodegradable – Plastic, DDT Benzene hexachroloride

  • Pollution caused by humans is called anthropogenic pollution. Anthropogenic pollution gives rise to non-biodegradable pollutants which do not get decomposed by organic decomposers or are decomposed very slowly. Therefore it is very difficult to reign in non-biodegradable pollutants caused by anthropogenic pollution.

  • Those pollutant which can be broken down into simpler harmless substances in nature in the due course of time (by the action of microorganism like certain bacteria) are called biodegradable pollutant . Domestic

waste (garbage), wine, fecal matter, sewage, cattle dung , animal bones etc are biodegradable pollutants .

  • Coal petrol and diesel burn to produce oxides of carbon and nitrogen which are the main factor behind air pollution.

  • Photochemical smog is a mixture of pollutants that are formed when nitrogen oxides (NO2), ozone (O3) and peroxyacetyl nitrate (PAN) reacts with sunlight, creating a brown haze above cities.

  • Noise pollution or nose disturbance is the disturbing or excessive noise that may harm the activity or balance of human or animal life. The source of most outdoor noise worldwide is mainly caused by machines and transportation systems, motor vehicles, aircraft and train.



  • Sound Source Sound (in DB)

Rustling of leaves                20 dB

Whispering                          30 dB

Room noise                          40 dB

Normal conversation           60 dB

Truck sound                         80-85 dB

Jet engine sound                  120 dB

Landing of Jet Plane            150 dB

Rocket engine                      180 dB

  • Carbon monoxide is main pollutant emission gas in vehicle exhaust.

  • Combustion of petrol in automobiles pollutes the air by producing lead which causes long term harm in adults including increased risk of high blood pressure and kidney damage.

  • PAN (Peroxycetyl Nitrate), Ozone and smog are secondary pollutants because these are formed after reaction of primary pollutants with atmosphere. While oxide of sulphur (mainly sulphur dioxide) an oxide of nitrogen, carbon monoxide are primary pollutants as these directly spread in the air and pollute and atmosphere.

  • Arsenic is a non-biotic pollutant of underground water. The introduction of Arsenic into drinking water can occur as a result of its natural geological presence in local bedrock. Presence of Arsenic in ground water is relatively high in areas adjoining banks of Ganga. Pesticides and insecticides also add to it’s presence in the ecosystem. According to WHO the amount of arsenic should be 0.05 mg/liter.



Arsenic born diseases

  • Black Foot

  • Skin Cancer

  • Diarrhoea

  • Lungs Cancer

  • Hyper Keratosis

  • Peripheral Neuritis

  • Acid rain is caused by a chemical reaction that begins when a compound like sulphur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere where they mix and react with water, oxygen and another chemical to form more acidic pollutants. When these pollutants fall on the surface with rain it is termed acid rain. Normally the pH value of acid rain is less than 5-6. Notably the pH value of pure water is 7.0.

  • Sulphur dioxide and “nitrogen” oxide are the main factors for acid rain. Acid rain contaminates rain water and snow. This produces adverse impact on rivers, lakes and ponds.

Acid rain’s harmful effect on aquatic system

  • Black food disease in animals

  • Fish death

  • Egg hatching Hampered

  • Death of May Fly- Lack of food for fogs

  • Formation of mucus over Gills by Acidic atoms

  • Food poisoning through drinking water and food

  • End of tissues salt balance because of low pH

  • Sulphur dioxide is an air pollutant gas and is released by burning fossil fuel.

  • Green Muffler is a control measure for noise pollution by planting green plants. Normally 4-5 rows of plants are grown near the noisy places like roadsides and industrial areas so that they can obstruct noise.

  • Bhopal disaster, also referred to as the Bhopal gas tragedy was a gas leak incident in India, considered the world’s worst industrial disaster. It occurred on the night of 3 December, 1984 at the Union Carbide India Limited pesticide plant in Bhopal, Madhya Pradesh. Over 500000 people were exposed to Methyl Isocyanate (MiC) gas. According to state government records 3787 people died in this tragedy. Later due to disease caused by the gas around 25000 people were killed.

  • Fly ash is one of the coal combustion products, composed of the fine particles that are driven out of the boiler with the flue gases. Fly ash is generally captured by electrostatic precipitators or other particle filtration equipments. Fly ash causes respiratory disease.

  • BOD indicates the amount of organic matter present in water. Therefore, a low BOD is an indicator of good quality water, while high BOD indicates polluted water.

  • BOD is maximum in the Ganga River between Kanpur and Allahabad as Kanpur discharge heavy amount of pollutants in Ganga. As result of which BOD is high here.

  • Bio-remediation is a process of detoxification of environment through the use of small organisms. This technique can help overcoming adverse effects of pollution at particular places. Bio-remediation is used in cleaning surface and ground water and soil etc.



  • Automobiles use lead as an antiknocking agent. Lead when released in the air with exhaust are most toxic. Lead affects the nervous system, brain and digestive system of human body.

  • Rain can wash out particles from the air. Washing works much better on larger particles (above 10 microns or above 2.5 microns) than small particles. Rains also help by making dust particles stick to the ground.

  • Damodar considered as “Sorrow of Bengal” due to its devastating floods, has now become the sorrow of both Jharkhand and Bengal owing to excessive pollution. The enormous quantity of pollutants coming out from the mines, industries, cities and agricultural fields have so much degraded the quality of river that it has virtually become a biological desert.

  • Argimon seed is usually mixed with mustard seed as an adulterant. It is form of poppy found in Mexico. Mixing of this in mustard oil could yield epidemic called dropsy.

  • Harmful algal blooms, lethal for a human being and marine ecosystems alike, are steadily increasing in intensity in Indian waters. Upwelling, the formation of mud banks, nutrient discharges from estuaries and run-off from land during south-west and north-east monsoons cause some algae blooms in coastal waters.

  • Cold air being relatively heavy than the warm air does not rise high in the atmosphere. Hence dust particles, pollutants and environmental dirt from a layer above the surface in atmosphere. This is reason for increased pollution level during winter in Delhi.

  • Soil pollution is more dangerous as compared to industrial pollution as fertilizers and pesticides used on crops enter into food cycle which affects the human health.

Effect of soil pollution

  • Deforestation – Global warming

  • Death of microorganisms – Impaction food chain

  • Soil erosion – Flood – Drought

  • Soil acidification

  • Soil alkalinization

  • Loss of fertility by hazardous chemicals

  • Water pollution

  • Entry of pollution is plant

  • Nanoparticlepollute water, soil and air. After being received by bacteria, the whole food chain can get affected. Nano particles of zinc oxide and titanium dioxide product free radicals.

  • According to survey by FICCI, Delhi generates the largest amount of solid waste per capita annually. Delhi generates 7000 metric ton solid waste every day whereas Mumbai generate 6500.

  • A catalytic converter is an emission control device that converts toxic gases and pollutants in the exhaust gas to less toxic pollutants by catalyzing a redox reaction. The catalyst itself is most often a mix of precious metals. Palladium and Platinum are two such precious metals used.

  • Euro Emission standard is pollution applicable to all automobiles in Europe. Euro norms place a limit on the amount of emission of oxides of nitrogen, carbon monoxide, all hydro carbons and suspended particulate matter.

  • To meet Euro-II emission standards, the sulphur content should be 0.05 percent or less than this in the ultra low sulphur diesel.



  • Like other countries India’s Air Quality Index is based on 8 major pollutants –

  1. <10 micro meter size particulate matter (PM10)

  2. <2.5 micro meter size particulate matter (PM)

  3. Nitrogen dioxide (NO2)

  4. Carbon Mono oxide (CO)

  5. Ozone (O3)

  6. Sulphur dioxide (SO2)

  7. Amonia (NH3)

  8. Lead (Pb)

CO and O3 are measured on the average of 8 hours and other pollutants are measured on the average of 24 hours, Measurement unit for NO2 and O3 is micro gram per cubic meter and for CO miligram per cubic meter.

  • Euro emission standards define the acceptable limits for exhaust emission of new vehicles sold in the European Union. Emission of nitrogen oxides, hydrocarbon, non-methane hydrocarbons, carbon monoxide and particulate matter are regulated for most vehicle type. It is notable that European countries introduced Euro I standard in 1992. Significantly, Mashelkar committee for National Autofuel Policy suggested implementation of Euro standard to control pollution. Importantly, BS IV standard was implemented in India starting April, 2017.



Water Conservation

  • World Water Conservation Day is an annual event celebrated on March 22. The day focuses attention on the importance of fresh water and advocates for the sustainable management of freshwater resources. The theme of World Water Conservation Day 2018 was “Nature for Water” to encourage people to “look for the answer in nature”.

  • Biotic resources are obtained from the biosphere (living and organic material) such as forests and animals the materials that can be obtained from them. Fossil fuels such as coal and petroleum are also included in this category because they are formed from decayed organic matter.

  • The “Central Ganga Authority” was constituted in February, 1985 under the aegis of former Prime Minister Rajiv Gandhi. In September, 1995 its name was changed to “National River Conservation Authority”.

  • The Government of India has given Ganga the status of National River and has constituted the National Gnaga River Basin Authority (NGRBA) on 20th February 2009  under section 3 (3) of the Environment Protection Act, 1986.

  • Rajendra Singh is a well-known water conservation from Alwar district, Rajasthan also known as “waterman of India”. He won the Stockholm Water Prize, an award as in 2015. Previously he won the Ramon Magsaysay Award 2001 for his pioneering work in community-based efforts in water harvesting and water management.

  • Due to the scarcity of water in desert, in some plants leaves are modified to reduce water loss. Hard and waxy leaves help to minimise water loss through diffusion. Water loss is also prevented in the form of gummy substance in leaves minimising the surface area to volume ratio. Throns have a high surface area but they help in water conservation. They also help in condensing moisture from air, which then drips to the ground and is absorbed by the roots.

  • The population of the Ganga River Dolphin has declined due to construction of dams and water pollution caused by pesticides, fertilizers and industrial effluents. Threatened ecosystem is posing a danger to the existence of fresh water dolphin. The Ganga River dolphin inhabits Ganges- Brahmaputra- Meghna and Karnaphuli- Sangu River systems of Nepal, India and Bangladesh. As per the reports these Dolphins often get trapped in fishing nets accidentally which puts them in danger. Industrial actions and intensive agriculture along the coast of the river have introduced new threats to the dolphins. Use of pesticides and fertilizers have impacted the fresh water biodiversity. This dolphin in among the four “obligate” fresh water dolphins in the world.



  • The main objective of the National Water Mission is “conservation of water, minimizing wastage and ensuring its more equitable distribution both across and within States through integrated water resources development and management”. National water Mission is a part of National Action Plan on “Climate Change which was started on 30 June, 2008. The five identified goals of the mission are

  1. Comprehensive water data base in public domain and assessment of impact of climate change on water resource

  2. Promotion of citizen and state action for water conservation augmentation and preservation

  3. Focused attention to vulnerable areas including over-exploited areas

  4. Increasing water use efficiency by 20%

  5. Promotion of basin level integrated water resources management.

  • In 1984 the Central Water Commission established “Irrigation Research and management Organisation”.

  • Ultraviolet water purification is the most effective method for disinfecting bacteria from the water. Ultra-violet rays penetrate harmful pathogens in water and destroy illness causing micro organisms. This is extremely efficient in eliminating their ability to reproduce. UV systems destroy 99.99% of harmful micro-organism without adding chemicals or changing water’s taste or odor.

  • Yamuna Action Plan (YAP) to clean the district river in the country was formally launched in 1993. It is a bilateral project between the Government of India and Japan. The YAP has so far completed two phases as YAP-1 and YAP-II. The YAP-1 covered Delhi, eight towns in Uttar Pradesh and six towns in Haryana. Under YAP II, the emphasis was on the 22 km stretch of the Yamuna in Delhi. Notably YAP III was launched on 7 May, 2016 under Namami Gange Programme.

  • National Lake Conservation Plan (NLCP) is a centrally sponsored scheme exclusively aimed at restoring the water quality and ecology of the lakes in urban and semi-urban area of the country. The objective of the scheme is to restore and conserve the urban and semi-urban lakes of the country degraded due to waste water discharge in to the lakes and other reasons, through in integrated ecosystem approach. The Sukhna Lake in Chandigarh, Bhoj in Madhya Pradesh and Pichola Lake in Udaipur, Rajasthan have been declared a Wetland covered under National Lake Conservation Plan.




  • Dakshin Gangotri is the first research base station of India situated in Antarctica. It is currently being used as a supply base and transit camp. India’s second research center “maitree” was established in 1988-89. India’s third research base “Bharati” was established in 2012.

  • Agenda-21 is non-binding voluntarily implemented action plan of the United Nations with regard to sustainable development. It is a product of Earth Summit (UN Conference on Environment and Development) held in Rio de Janeiro, Brazil in 1992. Agenda-21 is a 350 page document divided in to 40 chapters that have been grouped in to 40 sections.

  • Sun temple of Konark was included as a World Heritage Site in 1984 while Mahabali Temple complex at Bodh Gaya Bihar in 2002.

  • Biotechnology Park in Uttar Pradesh has been established in Lucknow. It was set up in 2003.

  • The “Kailash Sacred Landscape Conservation and Development Initiative” (KSLCDI) is a collaboration among India, China and Nepal.

  • Institute                            Place

National Institute of Nutrition                                 –        Hyderabad

Wild Life Institute of India                                      –        Dehradun

National Institute of Ayurveda                                –        Jaipur

National Institute of Naturopathy                            –        Pune

Forest Research Institute                                         –        Dehradun

Indian Grassland and Fodder Research Institute     –        Jhansi

Central Arid Zone Research Institute                      –        Jodhpur

Indian Agricultural Research Institute                    –        New Delhi


  • A tsunami is a series of large waves generated by an abrupt movement on the ocean floor that can result from an earthquake, an underwater landslide, a volcanic eruption or very rarely a large meteorite strike. However powerful undersea earthquakes are responsible for most tsunami.

  • Indian Institute of Forest Management is situated in Bhopal.

  • Indira Gandhi Paryavaran Puraskar is an environment award instituted by the Ministry of Environment and Forest, Government of India in the year 1987 in order to encourage public participation in environment. It is awarded to individuals and organizations that have made significant and measurable contribution in the field of environment protection and improvement.

  • Baba Amte was related to wild life conservation and Narmada Bachao Andolan and Dr. Salim Ali was related with Silent Valley Movement.

  • Rally for Valley programme was related to the settlement of displacement persons of Narmada Valley.

  • World Habitat Day is observed every year on the first Monday of October. It was officially designated by the United Nations and first celebrated in 1986.

  • World No Tobacco Day is observed around the world every year on May 31. It is intended to encourage abstinence from all forms of tobacco consumption around the globe.

  • The Central Arid Zone Research Institute was established by the Government of India in 1952 in Jodhpur, Rajasthan.



  • Helium is an inert gas which is filled in balloons used for weather science dispatch.

  • Salim Ali was an Indian ornithologist and naturalist. He is sometimes referred to as “birdman of India”. He in his book “Handbook of the birds of Indian and Pakistani Vol 5” wrote that common Myna stalking alongside the cattle seizes the insects disturbed by their movement through gasses.

  • Bombay Natural History Science (BNHS) India, a pan Indian wild life research organization, has been promoting the cause of nature conservation since 1883. Main activities of BNHS are –

  • Natural history collection

  • Research on various species and habitats

  • Conservation of landscapes and seascapes

  • Environmental Information system

  • Outreach (Camp, exhibitions, lectures, other events)

  • Communications and Advocacy

  • SODAR (Sonic Detection and Ranging) is a meterological instrument used as a wind profiler to measure the scattering of sound waves by atmospheric turbulence. SODAR systems are used to measure wind speed at various heights above the ground. In India, SODAR is established at Kaiga, Kalpakkam, Tarapur and Trombay.




  • In addition to the general labeling, every package of food shall carry the following information on the label, namely –

  1. The name of food

  2. List of Ingredients

  3. Nutritional information

  4. Energy value in Kcal

  5. The amounts of protein, carbohydrate (specify the quantity of sugar) and fat in gram (g) or m/

  6. The amount of the any other nutrient for which a nutrition or health claim is made

  7. Declaration regarding vegetarian or non-vegetarian

  8. Declaration regarding food additives etc.

  • Eco-Mark is an eco-labeling scheme which was constituted by the Government of India in 1991 for easy identification of environment friendly product.

  • Montana in the United States of America is called as graveyard of Dinosaurs.

  • Section 14(1) of the Disaster Management Act, 2005 empowers Governor of a state establish State Disaster Management Authority (SDMA). In each state, after the notification under Section 3(1) of this act, the Governor shall establish the state Disaster Management Authority.

  • If LANDSAT data for an area is received today, the data for an adjacent area to it’s west will be available after the certain number of days at the same local time due to revolution of the satellite around the earth.

  • AGMARK Act or Agriculture Produce (Grading and Marking) Act, 1937 is an Act to provide for the grading and marking of agriculture and other produce. It came into effect in 1937.















  • Mercury (Buddha) is closest to the sun. It has no atmosphere.

  • Venus (Shukra) is the closest neighbour of the earth. Its atmosphere has 96% carbon dioxide and poisonous gases like sulphur dioxide and carbon monoxide.

  • Mars (Mangal) is also close to earth. It is called the red planet. It has 95% carbon monoxide and reddish dust.

  • Jupiter (Brahaspati) is the largest planet of the solar system. It is mainly a rapidly spinning ball of gas specially clouds of ammonia, and has no solid surface

  • Saturn (Shani) consists mainly of hydrogen and helium. Its atmosphere has 90% nitrogen and a temperature of (-184ºC). It is also made up of hydrogen cyanide which is a highly poisonous gas. It is characterized by a ring that surrounds it

  • Uranus (Arun) is also a very cold planet. Uranus is a distant planet of solar system and 7 th in order from the sun. Uranus and Neptune are the outermost planets of the solar system. Uranus has a highly tilted rotational axis.

  • Neptune (Varun) is much smaller than earth, cold and dark with its surface coated with frozen methane.

  • Both bacteria and protists are unicellular. Then came multi cellular organisms, the fungi followed by plants and animals


  • Local environmental backlash

  • Salination of irrigated soils

  • Eutrophication

  • The Minamata disease

  • Extinction of wild life species


  • Regional Environmental backlash

  • Floods

  • Drought

  • Acid rain

  • Oil spills


  • Global backlash

  • Biodiversity loss

  • Global warming and green house effect

  • Collapse of marine fisheries



  • Ozone layer depletion

  • Consequences of deforestation

  • Soil erosion

  • Landslides

  • Silting

  • Loss of wild habitat

  • Loss of CO2 sink

  • Loss of medicinal and other useful plants

  • Pollution


  • Forests have been cleared for the various reasons-

  1. Developmental activities

  2. For timber and wood

  3. For pastures

  4. Shifting cultivation

  • Pure rain has a pH of 5.6 but in areas where industries burn oil and coal emit SO2 (sulphur dioxide)into the atmosphere and motor vehicles release NOx (compound of nitrogen) into air , the rain becomes more acidic reaching pH of 2.

  • ‘Ecology may be defined as the scientific study of the relationship of living organisms with each other and with their environment.’

  • The term ecology was first coined in 1869 by the German biologist Ernst Haeckel. It has been derived from two Greek words, ‘oikos’, meaning home or estate and ‘logos’ meaning study .

  • A large community unit, characterized by a major vegetation type and associated fauna, found in a specific climatic region is a biome

  • Habitat is the physical environment in which an organism lives. Each organism has particular requirements for its survival and lives where the environment provides for those needs.



  • The features of the habitat can be represented by its structural components namely

  1. space

  2. food

  3. water

  4. shelter

  • Earth has four major habitats-

  1. Terrestrial

  2. Freshwater

  3. Estuarine(Where rivers meet the ocean) &

  • The term niche means the sum of all the activities and relationships of a species by which it uses the resources in its habitat for its survival and reproduction.

  • A niche is unique for a species while many species share the habitat. No two species in a habitat can have the same niche. This is because if two species occupy the same niche they will compete with one another until one is displaced.

  • A species is defined as; “a group of similar populations of organisms whose members are capable of interbreeding, and to produce fertile offspring (children)”.

  • Species are generally composed of a number of distinct populations which freely interbreed even though they appear to be different in appearance


  • The primary reason for these extinctions is environmental change or biological competition.

  • Population’ is defined as a group of freely interbreeding individuals of the same species present in a specific area at a given time.

  • A population has traits of its own which are different from those of the individuals forming the population.

  • An individual is born and dies but a population continues.

  • Natality:The rate at which new individuals are born and added to a population under given environmental conditions is called natality



  • Study of pug marks can provide the following information reliably if analyzed skillfully:

  • Presence of different species in the area of study .

  • Identification of individual animals.

  • Population of large cats (tigers, lions etc.).

  • Sex ratio and age (young or adult) of large cats

  • In ecology the term community , or more appropriately ‘biotic community , refers to the populations of different kinds of organisms living together and sharing the same habitat.

  • Stratification of a community refers to the vertical layers of the vegetation.

  • Tropical forests represent a good example of vertical stratification.

  • These include from the forest floor to the top

  • Ground layer of mosses and liverworts associated with dead leaves and other. The bottom layer substances rich in organic matter .

  • Herb or grass layer, } The lower layer

  • Short shrub layer The middle layer 

  • Tall shrub layer

  • Layer of under storey of short trees,   

  • Layer of canopy of lower trees and The upper layer 

  • Over storey or emergent tree layer formed by tall trees.

  • Primary succession is much more difficult to observe than secondary succession because there are relatively very few places on earth that do not already have communities of organisms.

  • Furthermore, primary succession takes a very long time as compared to secondary succession as the soil is to be formed during primary succession while secondary succession starts in an area where soil is already present. The community that initially inhabits a bare area is called pioneer community.



  • The terminal (final) stage of succession forms the community which is called as climax community. A climax community is stable, mature, more complex and long lasting. The entire sequence of communities in a given area, succeeding each other, during the course of succession is termed sere

  • Succession that occurs on land where moisture content is low for e.g. on bare rock is known as xerarch. Succession that takes place in a water body , like ponds or lake is called

  • Competition :Adversely affects both species

  • Amensalism: This is a negative association between two species in which one species harms or restricts the other species without itself being adversely affected or harmed by the presence of the other species. Organisms that secrete antibiotics and the species that get inhibited by the antibiotics are examples of amensalism. For example the bread mould fungi Pencillium produce penicillin an antibiotic substance which inhibits the growth of a variety of bacteria. 

Parasite-host relationship 

  1. Plant parasite: Dodder (Cuscuta) plant is a parasitic weed that obtains moisture and nourishment by attaching to a green, living plant.

  2. Animal parasite: Ascaris or round worms are internal parasites found in the human intestines

  • Another example of commensalisms is the relationship between trees and epiphytic plants.

  • The tree gets no benefit from this relationship nor are they harmed.

  • Mutualism:

  • This is a close association between two species in which both the species benefit. For example of protocorporation the sea anemone, a cnidarian gets attached to the shell of hermit crabs for benefit of transport

  • However, some mutualisms are so intimate that the interacting species can no longer live without each other as they depend totally on each other to survive. Such close associations are called Symbiosis.

  • An example of such close mutualistic association is that of termite and their intestinal flagellates.



  • Flagellate protists (protozoans)

  • Another familiar example of symbiosis is seen in pollination of flowers where flowering plants are cross pollinated by the bees which benefit by getting nectar from the plants

  • Neutralism:

  • Neutralism describes the relationship between two species which do interact but do not affect each other .

  • True neutralism is extremely unlikely and impossible to prove.

  • Biotic interaction refers to the interaction taking place between individuals belonging to the same species (intra specific) or different species (interspecific).

  • Examples are (i) competition (ii) predation (iii) parasitism (iv) mutualism (v) symbiosis (vi) commensalism (vii) neutralism

  • Biosphere is very huge and cannot be studied as a single entity . It is divided into many distinct functional units called ecosystem.

  • In nature several communities of organisms live together and interact with each other as well as with their physical environment as an ecological unit. We call it an ecosystem.  The term ‘ecosystem’ was coined by A.G .  Tansley in 1935.  

  • An ecosystem is a functional unit of nature encompassing complex interaction between its biotic (living) and abiotic (non-living) components.

(a) Abiotic components (Nonliving): The abiotic component can be grouped into following three categories:-

(i) Physical factors:Sun light, temperature, rainfall, humidity and pressure. They sustain and limit the growth of organisms in an ecosystem.

(ii) Inorganic substances: Carbon dioxide, nitrogen, oxygen, phosphorus, sulphur , water , rock, soil and other minerals.

  • Organic compounds:Carbohydrates, proteins, lipids and humic substances.



  • Functions of ecosystem: Ecosystems are complex dynamic system. They perform certain functions. These are:-

(i) Energy flow through food chain 

(ii) Nutrient cycling (biogeochemical cycles) 

(iii) Ecological succession or ecosystem development 

(iv) Homeostasis (or cybernetic) or feedback control mechanisms

Types of ecosystems

  • Ecosystems are classified as follows:

  1. Natural ecosystems

  2. Manmade ecosystems

  • Natural ecosystems

  1. Totally dependent on solar radiation e.g. forests, grasslands, oceans, lakes, rivers and deserts. They provide food, fuel, fodder and medicines.

  2. Ecosystems dependent on solar radiation and energy subsidies (alternative sources) such as wind, rain and tides. e.g tropical rain forests, tidal estuaries and coral reefs.

  • Man made ecosystems

  1. Dependent on solar energy-e.g. Agricultural fields and aquaculture ponds.

  2. Dependent on fossil fuel e.g. urban and industrial ecosystems.

On the basis of extent of penetration of light a pond can be divided into euphotic(eu=true,photic=light),  mesophotic and  aphotic zones.



  • Pond animals can be classified into the following groups

  1. Zooplanktons are floating animals. Cyclops, Cypris

  2. Nektons are the animals that can swim and navigate at will. Eg. fishes  

  3. Benthic animals

  • Transfer of food energy from green plants (producers) through a series of organisms with repeated eating and being eaten is called a food chain.

  • During this process of transfer of energy some energy is lost into the system as heat energy and is not available to the next trophic level. Therefore, the number of steps are limited in a chain to 4 or 5.

  • There are two types of food chains :

  • Grazing food chains: which starts from the green plants that make food for herbivores and herbivores in turn for the carnivores.

  • Detritus food chains: start from the dead organic matter to the detrivore organisms which in turn make food for protozoan to carnivores etc.

  • Trophic levels in an ecosystem are not linear rather they are interconnected and make a food web. Thus food web is a network interconnected food chains existing in an ecosystem.

  • Food webs are more realistic models of energy flow through an ecosystem 

  • The flow of energy in an ecosystem is always linear or one way .

  • Ecological pyramids are the graphic representations of trophic levels in an ecosystem. They are pyramidal in shape and they are of three types:

  1. Pyramid of number: Always upright but in some instances the pyramid of number may be inverted, i.e herbivores are more than primary producers as you may observe that many caterpillars and insects feed on a single tree.

  2. Pyramid of biomass:This represents the total standing crop biomass at each trophic level. Standing crop biomass is the amount of the living matter at any given time. It is expressed as gm/unit area or kilo cal/unit area. In most of the terrestrial ecosystems the pyramid of biomass is upright. However , in case of aquatic ecosystems the pyramid of biomass may be invertede.g. in a pond phytoplankton are the main producers, they have very short life cycles and a rapid turn over rate (i.e. they are rapidly replaced by new plants). Therefore, their total biomass at any given time is less than the biomass of herbivores supported by them

  3. Pyramid of energy



  • The amount of energy decreases at each subsequent trophic level. This is due to two reasons:

  1. At each trophic a part of the available energy is lost in respiration or used up in metabolism. 

  2. A part of energy is lost at each transformation, i.e. when it moves from lower to higher trophic level as heat.

  • It is the ratio between the amount of energy acquired from the lower trophic level and the amount of energy transferred from higher trophic level is called ecological efficiency.

  • Lindman in 1942 defined these ecological efficiencies for the 1st time and proposed 10% energy is lost during every transaction from lower tropic level to higher tropic level.

  • Atmospheric nitrogen can be fixed by the following three methods:-

  • . Atmospheric fixation: Lightening, combustion and volcanic activity help in the fixation of nitrogen.

  • Industrial fixation: At high temperature (400 o C) and high pressure (200 atm.), molecular nitrogen is broken into atomic nitrogen which then combines with hydrogen to form ammonia. 

  • Bacterial fixation: There are two types of bacteria-

  1. Symbiotic bacteria e.g. Rhizobium in the root nodules of leguminous plants.

  2. Freeliving or symbiotic g. 1.  Nostoc 2.  Azobacter 3. Cyanobacteria can combine atmospheric or dissolved nitrogen with hydrogen to form ammonia.

  • Nitrification: It is a process by which ammonia is converted into nitrates or nitrites by Nitrosomonas and Nitrococcus  bacteria respectively . Another soil bacteria Nitrobacter can convert nitrate into nitrite.

  • Assimilation: In this process nitrogen fixed by plants is converted into organic molecules such as proteins, DNA, RNA etc. These molecules make the plant and animal tissue.

  • Ammonification: Living organisms produce nitrogenous waste products such as urea and uric acid. These waste products as well as dead remains of organisms are converted back into inorganic ammonia by the bacteria This process is called ammonification.  Ammonifying bacteria help in this process.

  • Denitrification: Conversion of nitrates back into gaseous nitrogen is called denitrification. Denitrifying bacteria live deep in soil near the water table as they like to live in oxygen free medium. Denitrification is reverse of nitrogen fixation.

  • Almost 95 % of the total water on the earth is chemically bound to rocks and does not cycle.

  • Out of the remaining 5%, nearly 97.3% is in the oceans and 2.1% exists as polar ice caps. Thus only 0.6% is present as fresh water in the form of atmospheric water vapours, ground and soil water .

  • The driving forces for water cycle are 1) solar radiation 2) gravity .

  • On an average 84% of the water is lost from the surface of the through oceans by evaporation. While 77% is gained by it from precipitation.  Water run of f from lands through rivers to oceans makes up 7% which balances the evaporation deficit of the ocean. On land, evaporation is 16% and precipitation is 23%.

  • Note that in a homeostatic system, negative feedback mechanism is responsible for maintaining stability in a ecosystem.



  • The main components of all the biogeochemical cycles are:-

  1. the reservoir pool that contains the major bulk of the nutrients soil or atmosphere.

  2. cycling pool which are the living organisms (producers, consumers and decomposers), soil, water and air in which it stays temporarily .

  • Coniferous forests are also known as ‘Taiga’. They extend as a continuous belt across north America and north Eurasia below the arctic tundra. There is no counterpart of these forests in southern hemisphere as there is no land at this latitude.

  • Some common birds are crossbill, thrushes, warblers, flycatchers, robin and sparrow .

  • India Grassland, Savanna

Desert plants

  • In some plants even the stem contains chlorophyll for photosynthesis.

  • The word tundra means a “barren land” since they are found in those regions of the world where environmental conditions are very severe. There are two types of tundra- arctic and

  • Alpine tundra occurs at high mountains above the tree line. Since mountains are found at all latitudes therefore alpine tundra shows day and night temperature variations.

  • Animals of tundra are reindeer, musk ox, arctic hare, caribous, lemmings and squirrel.

  • Salix arctica that is arctic willow has a life span of 150 to 300 years. They are protected from chill by the presence of thick cuticle and epidermal hair . Mammals of the tundra region have large body size and small tail and ear to avoid the loss of heat from the surface. The body is covered with fur for insulation.

  • Osmoregulation is the process by which a constant osmotic pressure is maintained in blood.

Tropical deciduous forests

  • Important trees of these forests are teak, sal, and sandalwood.

(iii)  Temperate broad leaf forests It mainly occur between 1500-2400 m altitudes in western Himalayas. Several species of Oak (Quercus) are found in these forests. Oak species are evergreen in the Himalayan

These species show peak leaf fall during summer but never become leafless. 

  • Temperate needle leaf or coniferous forests This type of forests are found in the Himalaya over 1700 to 3000 m altitude. These forests contain economically valuable gymnospermous trees like pine , deodar ,Cypress, Spruce and siver fir.

  • Vegetation growing at altitudes above 3600 m is usually known as alpine vegetation and it can be noticed that with the increment of the altitude, the plants show stunted growth. The trees like silver fir , pine, juniper and birch belong to this category . 

  • Chir pine grows throughout the northwest Himalayas, with the exception of Kashmir

  • The Thar desert in Rajasthan is an extension of the Sahara deserts through Arabian and Persian deserts. They extend from Punjab, Haryana, Rajasthan to Gujarat state. Indian deserts are divided into four main types: • hills, • plains with hills, • marshes and • plains with sand dunes.

  • The distinct Rann of Kutchch–Bhuj in Gujarat forms a separate zone with in Thar deserts due to its different climatic conditions. It represents vast saline flats.

  • Indian deserts support many threatened species of birds and mammals, such as Asiatic lion, wild ass, bats, scaly ant eater , desert fox, Indian gazzel, four horned antelope , white browed Bushchat, Great Indian Bustard, Cranes and Sandgrouse. 

  • Gulf of Kuchch is distinguished by the presence of living corals, pearl oyster , sea turtles and a large number of migratory birds like kingfisher , cranes ibis and herons.

  • Himalayas completely over 12 states



Western ghats 

  • The rainfall may vary from 100 to 500 cm. Soil is mainly red or black in most of the regions and rich in nutrients. 3500 species of flowering plants have been recorded from western ghats of which nearly1500 are endemic species. Nearly 209 species of fresh water fishes occur in these ghats of which 120 are endemic. Similarly out of 219 species of amphibians found here 106 are endemic.

  • Estuaries are richer in nutrients than fresh waters or marine waters therefore; they are highly productive and support abundant fauna.

Characteristics of mangrove ecosystem:-

(1) The mangrove forests include a diverse composition of trees and shrubs

(2) Plants are well adapted to high salinity (halophytic).

 (3) Resistant to tidal effect. 

(4) Tolerant to high temperature. 

(5) Roots bear pneumatophores ( or aerial roots ), which is an aerating system.

The animal communities are of two types:

  1. Permanent fauna mainly bentic are molluscs, crustaceans, polychaetes, insects and birds like kingfishers.

  2. Visiting fauna includes mollusks, echinomerms, crustaceans and birds which come from adjacent terrestrial ecosystems and rivers . Tree frogs, crocodiles, turtles and snakes are also found in these forests. They are breeding and spawning ground for many commercially important fishes. 



Sunderban mangroves are the only mangroves where tiger population is found.

  • Mangroves in India have been reduced to more than 50% during the last forty years.

  • They are subjected to both natural as well as anthropogenic threats

  • For example in Sunderbans collection of tiger prawn seeds for trade has greatly affected the other animals found in these forests.

  • Ecotone is a zone of junction between two or more diverse ecosystems e.g. the mangrove forests. They represent an ecotone between marine and terrestrial ecosystem. Some more examples of ecotone are – grassland, estuary and river bank

Characteristics of ecotone:

  1. It may be very narrow or quite wide.

  2. It has the conditions intermediate to the adjacent ecosystems. Hence ecotone is a zone of tension.

  3. It is linear as shows progressive increase in species composition of one in coming community and a simultaneous decrease in species of the other outgoing adjoining community .

  4. Awell developed ecotones contain some organisms which are entirely different from that of the adjoining communities.

  5. Sometimes the number of species and the population density of some of the species is much greater in this zone than either community. This is called edge effect.

The organisms which occur primarily or most abundantly in this zone are known as  edge species.

  • In the terrestrial ecosystems edge effect is especially applicable to birds. For example the density of song birds is greater in the mixed habitat of the ecotone between the forest and the desert

  • Natural ecosystems can be classified into two types: 1) terrestrial and 2) aquatic.

  • The main reasons for the modification of natural ecosystems are and

1) increasing human population

 2) increasing human needs and 

3) changing life styles.



  • Some examples of human modified ecosystems are:

  1. Agro-ecosystems

  2. Plantation forests

  3. Urban ecosystems

  4. Rural ecosystems

  5. Aquaculture

  6. Industrial areas

  7. Laboratory cultures

  • Characteristics of human modified ecosystems

  1. Highly simplified

  2. Species diversity is very low .

  3. Food chains are simple and small.

  4. Depend on human (anthropogenic) support for survival; need for fossil fuel energy , fertilizers, irrigation etc.

  5. Attract large number of weeds

  6. More susceptible to epidemic diseases.

  7. Suffer from soil erosion. 

  8. Highly unstable.

  • Pollution refers to the addition of any substance in the environment that has direct or indirect adverse effect on humans

  • Urban areas consume 75% of the earth’s resources and produce 75% of the waste.

  • The maximum population density is observed in Malta Africa. It is 1 100 persons/sq km. Next ranking is Bangladesh with 888persons/sq. km., Bahrin 759 persons/sq km, Netherland 441 persons/sq km and Japan 328 persons/sq km.

  • Presently there seems to be an urban revolution as people all over the world are moving into towns and cities. In year 1800, only 5% of the world population was urban-dwelling (50 million people) and in 1985 it increased to 2 billion.  At present 45% of the world population is urban population and by 2030 there will be more than 60% people living in cities.

  • Aquaculture is the artificial cultivation of aquatic plants or animals. It is primarily carried out for cultivating certain commercially important edible species of fresh and marine water fishes, molluscs, crustaceans and aquatic plants.

  • Fisheries include the extraction of food from the sea and the fresh water where as  aquaculture  is rearing of the aquatic organisms in artificially made water bodies



There are two types of aquaculture:

  1. Fish farming is cultivation of fish in a controlled environment often a coastal or inland pond, lake, reservoir or rice field (paddy) and harvesting when they reach the desired size.

  2. Fish ranching is a practice of keeping which fishes in captivity for the first few years in floating cages in coastal lagoons and releasing them from captivity into water bodies.

  • Tilapia is a very favourite fish of many . It is also known as aquatic chicken.

Merits of aquaculture 

  1. Ecological efficiency is high. 2 kg. of grains are required to add 1 kg live weight.

  2. High yield in small volume of water .

  3. Improved qualities of fish obtained by selection and breeding and genetic engineering.

  4. Aquaculture reduces over harvesting of fisheries.

  5. High profit

Demerits of aquaculture

  1. Large inputs of feed, water and land are required.

  2. Loss of native aquatic biodiversit. As it replaced by monoculture of a commercially important fish species. 

  3. Produces large amounts of fish wastes that pollute water bodies.

  4. Destroys mangrove forests or coastal vegetation.

  5. Aquaculture fishes are very sensitive to pesticide runoff from croplands.

  6. In aquaculture ponds high population density is maintained that makes them highly vulnerable to diseases leading to total collapse of the crop. 

  7. Aquaculture tanks or reservoirs are often get contaminated after a few years.

  • Secondary air pollutants formed from complex reactions between primary pollutants, such as smog and acid rain, which are harmful to all living organisms, buildings and monuments.

  • Human health

  • Increased sensitivity to diseases:

  • Genetic resistance

  • Effect on native populations

  • Stress due to overharvesting:

  • Effect on nutrient recycling:




  • Reduce our needs  Eco-industrial revolution

  • Quinine is used to treat malaria (from the cinchona tree);

  • Digitalis is used to treat chronic heart trouble (from the foxglove plant, Cinchona officinalis);

  • Morphine and Cocaine are used to reduce pain;

  • Drug for leukemia from Vinca rosea, taxol fromTaxus brevifolia  etc

  • Drugs which are derived from natural compounds amount to at least $40 billion worldwide sales annually .

  • Asprin, which is probably the world’s most widely used drug was developed according to a chemical “blueprint”, from a compound extracted from the leaves of tropical willow trees. Secondary air pollutants formed from complex reactions between primary pollutants, such as smog and acid rain, which are harmful to all living organisms, buildings and monuments.

  • Deforestation is a very broad term, which consists of cutting of trees including repeated lopping, felling, and removal of forest litter, browsing, grazing and trampling of seedlings. It can also be defined as the removal or damage of vegetation in a forest to the extent that it no longer supports its natural flora and fauna.

  • Almost 44% of the total global wood produced fulfils the fuel requirements of the world

  • India consumes nearly 135-170 Mt (Million tonnes) of firewood annually and 10-15 ha of 

  • About 4% the world’s population lives in special territories .These indigenous or tribal people have claims on a particular place



  • Deforestation affects both physical and biological components of the environment

  • Soil erosion and flash flood

  • Climatic change

  • Loss of biodiversity

  • The loss of top soil is in India, is 18.5% of the global soil loss. This is indeed very serious, considering the fact that India has only 2.4% of the land area of the world. (2)Climatic change Forests enhance local precipitation and improve water holding capacity of soil,

  • Biodiversity – (biological diversity) is a measure of variation, the number of different varieties, among living things.

  • Biodiversity can be expressed in number of ways, which includes the number of genetic strains (differences) within species and the number of different ecosystem in an area.

  • The most common expression of biodiversity is the number of different species, within a particular area (local biodiversity), or in a specific habitat (habitat biodiversity) or in the world (global biodiversity).

  • Biodiversity is not static. It changes over the time during evolution new species have come up while some species become extinct.

  • Over the past 2000 years, 600 species of animals have become extinct or are going to be extinct from the earth.



  • The shrinkage of green cover has adverse effects on the stability of the ecosystem. Poaching is another factor causing depletion of wildlife. The roll call of victims is endless

  • In Africa, in recent years, nearly 95 per cent of the black rhino population has been exterminated by poachers for their horns and over one third of Africa’s elephants have been wiped out for ivory .

  • The scarlet macaw once common throughout South America has been eliminated from most of its range in Central America. Several species of spotted cats such as the ocelot and jaguar are in danger of extinction due to demand of their fur

  • India has nearly 45,000 species of plants and 75,000 species of animals. This biological diversity ought to be preserved for maintaining stability of ecosystems.

  • Deforestation coupled with desertification has destroyed the natural treasure of the earth to a large extent. The population of elephant, lion and tiger is fast diminishing. ‘Cheetah’ is already extinct. Elephants once found all over India have now disappeared from Andhra Pradesh, Madhya Pradesh and Maharashtra. 

  • The Asiatic lion which was very common in Asia has practically vanished from Asia except for a few hundred sq km (square kilometer) of Gir forest in India. In India four species of mammals and three species of birds have been extinct in the last 100 years.  Another 40 species of mammals, 20 species of birds and 12 species of reptiles are considered highly endangered due to overexploitations, of forests.

  • It can be defined as ‘the diminution or destruction of the biological potential of the land which can ultimately lead to desert like conditions’.

  • Desertification is a systemic phenomenon resulting from excessive felling of trees which manifests itself in the loss of soil fertility , high wind velocity , low precipitation, increasing aridity and extremes of temperatures in the affected area.



  • Most of the deserts of recent origin have resulted from any one or more of the following human activities.

  1. Uncontrolled and overexploitation of grazing land, indiscriminate cutting of trees and forest resources leading to drought, soil erosion, deterioration of soil fertility which results in stunted plant growth.

  2. Excessive mining in arid and semi-arid regions for extraction of minerals, coal or limestone resulting in loss of trees, and green cover , and leading to total destruction of conditions conducive to vegetation growing.

  3. Uneconomic land use for agriculture by cultivation on marginal lands affecting adjacent fertile lands and causing soil erosion.

  4. Intensive and uneconomic exploitation of water resources leading to fall in water table, seepage and problems of excessive salinisation of soil.

  • About 76.15% of the total Indian desert area has resulted from manmade desertification process. Another 19.5% of the total area is subjected to medium or slight desertification. This area is concentrated mostly along the eastern Rajasthan in the north-east to south-west zone parallel to the foothills of Aravalis.

  • The large terrestrial reptile, the rock python found on the foothills of Aravali is also vanishing from the desert.

  • There are three major functions of the forests

  1. productive functions .

  2. protective functions

  • regulative functions.

Plant Medicinal use

  1. Cinchona Officinalis Treatment of malaria

  2. Dititalis purspusla Treatment of chronic heart disease

  3. Vinca rosea Treatment of cancer

  4. Taxus brevifolia Treatment of cancer



Tehri town, at the junction of Bhagirathi and Bhilganga.

  • Pollution may be defined as addition of undesirable material into the environment as a result of human activities. The agents which cause environmental pollution are called pollutants. A pollutants may be defined as a physical, chemical or biological substance unintentionally released into the environment which is directly or indirectly harmful to humans and other living organisms.

  • Tetraethyl lead (TEL) is used as an anti-knock agent in petrol for smooth and easy running of vehicles. The lead particles coming out from the exhaust pipes of vehicles is mixed with air. If inhaled it produces injurious effects on kidney and liver and interferes with development of red blood cells. Lead mixed with water and food can create cumulative poisoning. It has long term effects on children as it lowers intelligence.

  • Loss of chlorophyll in plants (chlorosis)

  • Sulphur compounds- Power plants and refineries •Respiratory problems in humans (SO 2 and H 2 S)

  • Nitrogen Compound- Motor vehicle exhaust

  • Irritation in eyes and lungs (NO and N2O) atmospheric reaction

  • Low productivity in plants

  • Use of biogas &CNG (Compressed Natural Gas) need to be encouraged. Those species of trees such as baval (Acacia nilotica) which are least smoky should be planted and used. Charcoal is a comparatively cleaner fuel. Indoor pollution

  • Noise level is measured in terms of decibels (dB). W .H.O. (World Health Organization) has prescribed optimum noise level as 45 dB by day and 35 dB by night.  Anything above 80 dB is hazardous.

Prevention and control of noise pollution

 Following steps can be taken to control or minimize noise pollution-

  • Road traffic noise can be reduced by better designing and proper maintenance of vehicles.

  • Noise abatement measures include creating noise mounds, noise attenuation walls and well maintained roads and smooth surfacing of roads

  • Retrofitting of locomotives, continuously welded rail track, use of electric locomotives or deployment of quieter rolling stock will reduce noises emanating from trains.




  • In Gandhigram, a coastal village in Kutch district, the villagers had been facing a drinking water crisis for the past 10 to 12 years. The groundwater table had fallen below the sea level due to over extraction and the seawater had seeped into the ground water aquifers. The villagers formed a village development group, Gram Vikas Mandal. The Mandal took a loan from the bank and the villagers contributed voluntary labor (Shramdan).  A check dam was built on a nearby seasonal river , which flowed past the village. 

  • Success stories like the revival of the Aravari river basin by the waterman of Rajasthan-Rajender Singh –are already well known.

  • BS discuss these issues with villagers in the chosen hill areas through hundreds of hours of meetings over several months until they all agree to suspend browsing by cows for 3 years, goats for 5 years and camels for 7 years.

  • Issues of use and sharing have been settled before construction began rather than later . Such works are forever and the 5 years of deliberation recedes into significance.

  • This agreements leads to what TBS calls ‘social fencing’ which, in contrast with physical fences, is virtual; only in mind. With great fanfare, elders lead villagers on a walk through the entire line of the agreed ‘social fence’, sanctify it by sprinkling a mixture of scared waters and milk.



  1. Conservation by surface water storage: Storage of water by construction of various water reservoirs have been one of the oldest measures of water conservation.

  2. Conservation of rain water

  3. Ground water conservation

Some of the techniques of ground water management and conservation are described below 

(i)  Artificial recharge

(ii) Percolation tank method- Percolation tanks are constructed across the water course for artificial recharge. The studies conducted in a Maharashtra indicates that on an average, area of influence of percolation of 1.2 km , the average ground water rise was of the order of 2.5 m

(d)  Catchment area protection (CAP) 

Catchment protection plans are usually called watershed protection or management plans. These form are an important measure to conserve and protect the quality of water in a watershed. It helps in withholding runoff water albeit temporarily by a check bund constructed across the streams in hilly terrains to delay the run off so that greater time is available for water to seep underground. Such methods are in use in north-east states, in hilly areas of tribal belts.  This technique also helps in soil conservation.  Afforestation in the catchment area is also adopted for water and soil conservation.



(e)Inter -basin transfer of water

(f) Adoption of drip sprinkler irrigation -Surface irrigation method

(g)Management of growing pattern of crops

  1. i) In water scarce areas, the crop selection should be based on efficiency of the crop to utilize the water

(ii)Nutritional management: Potassium plays a major role under stress conditions. It improves the tissue water potential by osmoregulation, ultimately increasing the water use efficiency .

  • Role of anti-transpirants: Application of anti-transpirants reduces transpiration maintaining thereby the tissue water potential. Plants then take up less water from soil. Anti-transpirants can prolong the irrigation intervals by slowing down soil water depletion.

(h)Reducing evapo-transpiration

  • This can be prevented by placing water tight moisture barriers or water tight mulches on the soil surface. Non-porous materials like papers, asphalt, plastic foils or metal foils can also be used for preventing evaporation losses.

(i)Reducing evaporation from various water bodies

(j)Recycling of water

  • Grey water is defined as untreated household waste-water , which has not come into contact with toilet waste




  • EIA is a tool which helps to evaluate environmental impact of proposed developmental projects or programs are visualized clearance accorded after mitigation strategies are included in the plan.

  • EIA thus proves to be a tool which improves decision making and ensures that the project under construction is environmentally sound and within limits of the capacity of assimilation and regeneration capacities of the ecosystem. Environmental clearance of developmental projects is mandatory for the new project.

The important aspects of EIA are: 

  • risk assessment,

  • environmental management &

  • post product monitoring.

EIA was introduced in India in 1978, with respect to river valley projects. Later the EIA legislation was enhanced to include other developmental sections 

The goal of EIA is to ensure environmentally safe and sustainable development.

The EIA process looks into the following components of the environment

  • Air environment

  • Noise

  • Water environment

  • Biological environment

  • Land environment

  • Biological stress (prediction).

  • Steps in EIA process EIA involves the steps mentioned below . However , EIA process is cyclical with interaction between the various steps.

  • Screening:The project plan is screened for scale of investment, location and type of development and if the project needs statutory clearance.

  • Scoping: The project’ s potential impacts, zone of impacts, mitigation possibilities and need for monitoring. The EIA agency has to follow the published guidelines by the Ministry of Environment and Forest (MoEF) of government of India. 

  • Collection of baseline data: Baseline data is the environmental status of study area.

  • Impact prediction: Positive and negative, reversible and irreversible and temporary and permanent impacts need to be predicted which presupposes a good understanding of the project by the assessment agency .



  • Mitigation measures and EIA report: The EIA report should include the actions and steps for preventing, minimizing or by passing the impacts or else the level of compensation for probable environmental damage or loss.

  • Public hearing: On completion of the EIA report, public and environmental groups living close to project site may be informed and consulted.

  • Decision making: Impact Assessment (IA) Authority along with the experts consult the project-incharge along with consultant to take the final decision, keeping mind EIA and EMP (Environment Management Plan).

  • Monitoring and implementation of environmental management plan: The various phases of implementation of the project are monitored. • Risk assessment: Inventory analysis and hazard probability and index also form part of EIA procedures.

  • The Central Pollution Control Board (CPCB), is statutory organisation, was constituted in September , 1974 under the Water (Prevention and Control of Pollution)  Act, 1974. Further , CPCB was entrusted with the powers and functions under the  Air (Prevention and Control of Pollution)  Act, 1981.

  • Indian Board for Wildlife (IBWL) The IBWL is the apex advisory body in the field of Wildlife Conservation in the country and is headed by the Honorable Prime Minister of India. 

  • UNEP was created by United Nations General Assembly , as an outgrowth of the United Nations Conference on the Human Environment, held in Stockholm, Sweden

  • It is headquartered in Nairobi(Kenya).

  • One view is that humans are the dominant and important species on the planet earth. That gives them the power to manipulate and use nature for their own benefit. This view is “human centred” and thus it is called anthropocentric.

  • There are basically three approaches to environmental ethics.

  • Environmental wisdom talks of total dependence of humans on nature and the nature is for all species. This is life centric or biocentric approach. An extension of the above view seeks respect for all life and demands reverence towards the entire environment. Such a non-anthropocentric approach that talks of ethical responsibility towards other species and even ecosystems is also called ecocentric.

  • Indian philosophy aims not only at the well being of all humans but also of all beings. The Sanskirt verse: “Sarve Bhavantu Sukhinah Sarve Santu Nirmayah”

  • Refers to “May all be sinless and may all experience happiness.” The Vedas, Mahabharata and Ramayana all chant praises about cosmic harmony and environmental protection. 

  • Nature and environment were given importance from Rigvedic period onwards. Verse states- “the sky is like a father , the earth like a mother and space like their son”.

  • In the school curriculum activities such as (i) growing plants and taking care of them (ii) visits to national parks and sanctuaries (iii) creating stories/ poems/ plays on nature conservation, should be included.



  • Bishnois of Rajasthan had once upon a time laid down their lives to protect the local Khejdi trees

  • The Chipko movement (Chandi Prasad Bhatt and Sunder Lal Bahuguna), Baba Amte and Medha Patkar (Narmada Bachao  Andolan) all derived inspiration from Gandhi. 

  • His writings in ‘Hind Swaraj’ published in 1909 explained how the current mode of development is “exploitative of man by man and of nature by man”



Organic farming

  • Organic farming is a type of agriculture or farming which avoids the use of synthetic fertilizers, pesticides, growth regulators, and livestock feed additives.

  • Organic farming systems rely on crop rotation, crop residues, animal manures, legumes, green manure, off-farm organic wastes and biofertilizers, mechanical cultivation, mineral bearing rocks to maintain soil productivity to supply plant nutrients and biological pest control, controlling weeds, insects and other pests.

  • All kinds of agricultural products can be produced organically , including grains, meat, dairy , eggs, fibres such as cotton, jute, flowers etc. Thus organic farming creates a sustainable lifestyle for generations to come.

  • Organic farmers build healthy soils by nourishing the living component of the soil, the microbial inhabitants that release, transform, and transfer nutrients.

  • Soil organic matter contributes to good soil structure and water-holding capacity .

  • Organic farmers feed soil biota and build soil organic matter with cover crops, compost, and biologically based soil amendments. These produce healthy plants that are better able to resist disease and insect predation.

  • Organic farmers’ primary strategy in controlling pests and diseases is prevention through good plant nutrition and management. Organic farmers use cover crops and sophisticated crop rotations to change the field ecology , effectively disrupting habitat forweeds, insects, and disease organisms.

  • Weeds are controlled through crop rotation, mechanical tillage, and hand-weeding, as well as through cover crops, mulches, flame weeding, and other management methods.

  • Organic farmers rely on a diverse population of soil organisms, beneficial insects, and birds to keep pests in check. When pest populations get out of balance, growers implement a variety of strategies such as the use of insect predators, mating disruption, traps and barriers.

  • It has been found that by switching to organic farming, conventional farmer can actually reduce its production cost by over 25% as compared to the cost of conventional farming. This is eliminate the use of expensive synthetic fertilizers and pesticides, minimizing soil erosion by up to 50% and increasing crop yields up to five-folds.

  • Not only does wildlife benefit, but entire ecosystems and ground water are improved by simply following organic farming methods.

  • When dairies feed their cows organic feed and graze them on organic fields, the cows experience better health, less sickness, diseases and ultimately produce better tasting milk for consumers.



  • Organic farming promotes healthy soils that are teaming with life and rich in micro nutrients and which can be used for decades to grow crops without getting exhausted.

  • Consumers purchasing organically grown foods are tastier. Regardless of minimal price differences, consumers can smell, taste and see the difference in the quality of organically grown food products.

  • Organically grown products are free from harmful chemicals, artificial flavors and preservatives that ultimately cost consumers more money than non-organically grown products

  • The most sustainable way to control pests is a carefully designed integrated pest management (IPM) program. In this approach, each crop and its pests are evaluated as parts of an ecological system. Then farmers develop a control programe that includes cultivation, biological and chemical methods applied in proper sequence and with the proper timing. The aim of IPM is not to eradicate the pest population completely but to keep the crop damage to economically tolerable level

  • Farmers monitor the field and when they find the pest level to be high enough, they first use biological methods and cultivation practices to control and then use small amounts of insecticides mostly insecticides derived from plants as a last resort

  • (a) Biological control includes natural predators, parasites and pathogens of the pests are used. Examples are: • Pest on cucumber plant called red spider mite

  • Citrus fruits in California heavily damaged by scale insects which were controlled by Australian ladybird which ate away the insects.

(b)  Cultivation practices:  A variety of cultivation practices like crop rotation, polyculture and inter cropping etc. can be used to get rid of the pests.

(c) Some amounts of insecticides, mostly of plant origin (e.g. Pyrethrum and Rotenone neem product) are applied as a last resort.

(d) Pest and disease resistant crop :plants can be produced by genetic engineering. Ex – Bt cotton

  • Pest control method has some disadvantages:

  • Farmer should have an expert knowledge about each pest.

  • It acts more slowly than conventional pesticides

  • Methods developed for a crop in one area might not apply to areas with even slightest different growing conditions.

  • Initial cost may be higher but in the long-term cost become very low .

  • By slowing down and controlling ripening in tomato by introducing a bacterial gene that prevents ethylene formation thus delays ripening.

  • Frost resistant tomatoes have been produced by introducing gene for antifreeze proteins from polar fish living in ice water .

  • Controversies on GM products

(i)  Safety 

  • Potential human health impact: allergens, transfer of antibiotic resistance markers, unknown effects.



  • Potential environmental impact: unintended transfer of transgenes through cross-pollination, unknown effects on other organisms (e.g., soil microbes) and loss of flora and fauna biodiversity

(ii)  Access and intellectual property

(iii)  Ethics

  •  Violation of natural organisms’ intrinsic values.

  • Tampering with nature by mixing genes among species. 

  • Objections to transferring animal genes in plants and vice versa.

  • Stress for animal.

(iv) Labeling

(v)  Society

  • New advances may be skewed to interests of rich countries.

  • Industries may interact in such a way that they establish a “resource exchange” programme in which waste of one industry or manufacturer is utilized as raw material by another-industry- similar to food web in nature.

  • Bioremediation is the process in which a living organism (plant/animal/bacteria) is deployed to make a hazardous wastes harmless. For example bacteria and enzymes help to destroy toxic and hazardous substances or convert them in harmless compounds.

  • Radiation emitted natural sources is known as “background radiation”,because it is present everywhere, all the time.

  • Huge amount of heat is generated in nuclear power plants, only one third of the heat is used in generating electricity and two third is lost as waste heat.

When the world entered the atomic age, the problem or the dangers of disposal of nuclear waste were not fully realized. It is now becoming increasingly clear that safe disposal of nuclear waste is not easy and simple. Radioactive wastes are of two types 



(1) low level radioactive wastes (LLW) which include civilian applications of radio nuclides in medicine, research and industry , materials from decommissioned reactors, protection clothing worn by persons working with radioactive materials or working in nuclear establishments.

(2) High level radioactive wastes (HLW) results from spent nuclear fuel rods and obsolete nuclear weapons.

  • Some proposed methods of disposing nuclear waste are:

  • bury it deep underground in insulated containers. This is a strategy being pursued in United States.

  • shoot it into the space or into the sun. The cost would be very high and a launch accident should be disastrous.

  •  bury it under the ice sheet of Antarctica or Greenland ice cap. The ice could be destabilized by heat from the waste. The method has been prohibited by international law 

  • Dump it into deep oceans by keeping the waste into glass and steel cases. But the containers might leak and contaminate the ocean. Both HLWand LLW into the Atlantic ocean.  The method is prohibited by international law . 

  • Until 1983, European countries had been dumping .After 1983 when dumping was stopped, by law 90,000 metric tons waste had been disposed in the ocean. • change it into harmless or less harmful isotopes. Currently no method is known to do that and the method would be too costly .

  • Presently waste fuel rods are being stored in special storage ponds at reactor sites or sent to reprocessing plants. Even though reprocessing is more expensive but some countries use reprocessing as an alternative to waste storage.



  • Potentially usable sites or locations where nuclear waste can be disposed off should have some characteristics

  • low precipitation;

  • absence of surface waters;

  • low possibility of tectonic movement;

  • adequate buffer zone (in case the waste gets loose)

  • Labeling of environmentally beneficial goods and resources extracted by more sustainable methods can help consumers decide which goods and services to buy. Product eco-labelling can encourage companies to develop green products and services and help consumers select more environmentally beneficial products and services.

  • Some consumer products to meet certain environment criteria alongwith quality requirements of Indian standards. The label is known as ‘Eco mark’.

  • Eco-label is issued by the Central Pollution Control Board (CPCB) is represented by a pitcher or an ‘earthen pot’

  • The 42nd amendment Clause (g) to Article 51A of the Indian constitution made it a fundamental duty to protect and improve the natural environment.

  • The Act vests regulatory authority in State Pollution Control Boards and empowers these Boards to establish and enforce  effluent standards for factories discharging pollutants into water bodies. 

  • A Central Pollution Control Board performs the same functions for Union  Territories and formulate policies and coordinates activities of different State Boards.

  • In the wake of the Bhopal tragedy , the government of India enacted the Environment (Protection) Act of 1986. 

  • A state may declare forestlands or waste lands as reserved forest and may sell the produce from these forests. Any unauthorized felling of trees quarrying, grazing and hunting in reserved forests is punishable with a fine or imprisonment, or both. Reserved forests assigned to a village community are called  village forests. The state governments are empowered to designate protected forests and may prohibit the felling of trees, quarrying and the removal of forest produce from these forests. 

  • There is provision for notifying National Heritage Sites important from standpoint of biodiversity by State Governments in consultation with local self-government.

  • A protocol is an international agreement that stands on its own but is linked to an existing convention

  • The United Nations Educational, Scientific and Cultural Organisation (UNESCO) serves as the Depositary for the Convention, and its secretariat, the Ramsar Bureau, is in Gland, Switzerland.

  • The United Nations Environment Programme (UNEP) has been addressing this issue since 1977. Under the auspices of UNEP , the nations of the world arrived at The Convention for the Protection of the Ozone Layer  in  Vienna in 1985.



  • The Montreal Protocol uses three kinds of provisions as economic incentives to encourage participation and compliance with the Protocol’ s control regime;

 (1) entry into force requirements,

(2) controls on trade with non-parties, and

(3) research and technology transfer benefits.



Soil Management:

  • Methods of protection include using cover crops, compost, reducing tillage, conserving soil moisture by dead mulches, this increases water hold capacity of the soil.

  • Some of the objectives of varietal improvement are:

  1. development of high yielding varieties of crop plants.

  2. food crops developed for better and higher nutritional quality like protein quality

  3. development of crop varieties resistance to diseases and pests.

  4. improving varieties for resistance against heat, cold, frost, draught and water logging.

  • Bio-fertilizers are living or biologically active products or microbial inoculants of bacteria, algae and fungi (separately or in combination) which are able to enrich the soil with nitrogen, phosphorus, organic matter etc.

  • Rhizobium biofertilizer: Rhizobium is a symbiotic bacteria forming root nodules in legume plants. These nodules act as miniature nitrogen production factories in the fields.

  • Azotobacter biofertilizer: Azobacter are aerobic free living nitrogen fixers. 

  • Azospirillium biofertilizer:These are aerobic free living nitrogen fixers which live in associative symbiosis.

  • Blue green algae: Blue green algae (BGA or cyanobacteria) like Nostoc and Anabaena are free living phostosynthetic organisms also capable of fixing atmospheric nitrogen. In the flooded rice fields blue green algae serves as a nitrogen biofertilizer .

  • Azolla biofertilizers: Azolla is a water fern inside which grows the nitrogen fixing blue green algae   

  • This can be grown in a cooler regions. But there is a need to develop a strain that can tolerant to high temperature, salinity and resistant to pests and diseases.

  • The only constraint in Azolla is that it is an aquatic plant and water becomes limiting factor in growing it particularly in summer .

  • Phosphorus solubilising biofertilizer:   Mycorrhizal fungi acts as biofertilizer are known to occur naturally on roots of forest trees and crop plants.The fungus has the ability to dissolve and absorb phosphorus that plant roots cannot readily absorb.




  • Ozone (O3) layer can be destroyed both by natural and man-made causes-

(i) Natural causes:  A number of naturally occurring substances destroy stratospheric ozone. Most important of these compounds are: Hydrogen oxide (HO x ), Methane (CH 4 ), Hydrogen gas (H 2 ), Nitrogen oxides (NO x ). 

  • Chlorine monoxide (ClO); during volcanic eruptions, significant amount of chlorine may be released in the stratosphere. Tiny particulate matter in the stratosphere, known as stratospheric aerosols, may also lead to ozone destruction.

  • A small amount of uv-radiation is necessary for well-being of human beings and other organisms, such as UV-B promote synthesis of vitamin-D. UV -radiation also act as a germicide to control micro-organisms.

  • Acid precipitation affects both aquatic and terrestrial organisms. It also damages buildings and monuments.

(i) Effects on aquatic life: The pH of the surrounding or medium is very important for metabolic processes of aquatic organisms. The eggs or sperms of fish, frogs and other aquatic organisms are very sensitive to pH change.  Acid rain kills their gametes affecting the life cycles and productivity . 

  • Acidic lake waters may kill bacteria/microbes/planktons and the acidic lakes become unproductive and life less. Such acidic and lifeless ponds/lakes adversely affect fisheries and livelihood.

(ii) Effect on terrestrial life: Acid rain damage cuticle of plant leaves resulting etiolation of foliage. This in turn reduces photosynthesis. Reduced photosynthesis accompanied by leaf fall reduces plant and crop productivity . Acidic medium promotes leaching of heavy metals such as aluminum, lead and mercury . Such metals when percolate into ground water affect soil microflora/ micro fauna. 

(iii) Effects on forests: Acid rains damage forests and kill vegetation and causes severe damage to the landscape.

  • Effect on buildings and monuments: Many old, historic, ancient buildings and works of art/textile etc. are adversely affected by acid rain. Limestone and marble are destroyed by acid rain. Smoke and soot cover



Species diversity can be measured in terms of: 

(a) Species richness –refers to the number of various species in a defined area.

(b) Species abundance –refers to the relative numbers among species. For example, the number of species of plants, animals and microorganisms may be more in an area than that recorded in another area. 

(c) Taxonomic orphylogenetic diversity –refers to the genetic relationships between different groups of species.

  • India is a country of vast diversity and it is among the 12 “mega-diversity” countries in the world

  • Species diversity is not evenly distributed across the globe. The overall richness of species is concentrated in equatorial regions and tends to decrease as one moves from equatorial to polar regions. In addition, biodiversity in land ecosystems generally decreases with increasing altitude. The other factors that influence biodiversity are amount of rainfall and nutrient level in soil. In marine ecosystems, species richness tends to be much higher in continental shelves.

  • Norman Myers, a British Ecologist, developed the concept of hot spots in 1988 to designate priority areas for insitu    According to him, the hot spots are the richest and the most threatened reservoirs of biodiversity on the earth. 



The criteria for determining a hot spot are:

  1. i) The area should support >1500 endemic species

  2. ii) It must have lost over 70 % of the original habitat

  • India accounts for only 2.4 % of the land area of the world; but it contributes approximately 8% species to the global diversity due to existence of such pockets.

  • The threat to survival or loss may be caused in the following three ways: 

  • Direct ways: Deforestation, hunting, poaching, commercial exploitation.

  • Indirect ways:  Loss or modification of the natural habitats, introduction of exotic species, pollution, etc.

  • Natural causes – Climate change.

  • Exotic species  (new species entering geographical region) may wipe out the native ones.  A few examples are

(i) Parthenium hysterophorus (Congress grass- a tropical American weed) has invaded many of the vacant areas in cities, towns and villages in India leading to removal of the local plants and the dependent animals. 

(ii) Nile perch, an exotic predatory fish introduced into Lake Victoria (South Africa) threatened the entire ecosystem of the lake by eliminating several native species of the small Cichlid fish that were endemic to this freshwater aquatic system.

iii) Water hyacinth clogs lakes and riversides and threatens the survival of many aquatic species. This is common in Indian plains.

 (iv) Lantana camara  (an  American weed) has invaded many forest lands in various parts of India and wiped out the native grass species.



 A Biosphere Reserve consists of core, buffer and transition zones. 

(a) The  core zone is fully protected and natural area of the Biosphere Reserve least disturbed by human activities. It is legally protected ecosystem in which entry is not allowed except with permission for some special purpose. Destructive sampling for scientific investigations is prohibited. 

(b) The buffer zone surrounds the core zone and is managed to accommodate a greater variety of resource use strategies, and research and educational activities.

 (c) The  transition zone, the outermost part of the Biosphere Reserve, is an area of active cooperation between the reserve management and the local people, wherein activities like settlements, cropping, forestry , recreation and other economic that are in harmony with the conservation goals.

Ex-situ Conservation

(i) Botanical gardens, zoos, etc.

(ii) Gene Banks :

(iii) Cryopreservation:(“freeze preservation”) is particularly useful for conserving vegetative propagated crops. Cryopreservation is the storage of material at ultra low temperature of liquid nitrogen (-196 0 C) and essentially involves suspension of all metabolic processes and activities. 

  • Conservation at molecular level (DNA level):

  • Natural gas contains methane and smaller amounts of propane and butane. When a natural gas field is tapped, propane and butane gases are liquefied and removed as liquefied petroleum gas (LPG). The rest of the gas (mostly methane) is dried to remove water vapour, cleansed of poisonous hydrogen sulphide and pumped into pressurized pipelines for distribution. At a very low temperature, natural gas can be converted into liquefied natural gas (LNG).

  • Ferrous metallic minerals Non-ferrous metallic minerals (Iron, Mangnese, Chromite). Gold, Silver, Copper , Tin, Zinc, Aluminium (Bauxite ore)

  • Haematite is red in colour, called ‘red ore’ and has 68% iron. Magnetite is dark brown in colour called ‘black ore’ and has 60% iron. Limonite is yellow in colour and has 35% iron.

  • India ranks third in the production of manganese ore in the world.



  • it is also used in the manufacture of dry batteries, in photography , leather and match industries

  • Bauxite is also used in the manufacture of white colour cement and certain chemicals. 

  • Zinc is mainly used in tyre industry . It is also used in dye, casting, dry batteries, textile etc.

  • Limestone, phosphorite, kaolin, gypsum and magnesite are significant non-metallic minerals.

  • Almost 76% of country’ s total consumption is used in cement industry , a lar ge amount is used in iron and steel industry .

  • India is the leading producer of sheet mica. Bihar and Jharkhand produce the high quality ruby-mica.

  • These are mainly used for manufacturing of phosphate fertilizers. Rajasthan is the leading producer followed by Uttaranchal, Madhya Pradesh and Uttar Pradesh.

  • One way to improve mining technology is to use microorganisms to extract metals from its ores known as “biomining” or ‘ecological engineering’

  • Slight degradation refers to the condition that where crop yield potential is reduced by 10%.

  • Moderate degradation refers to 10-50% reduction in yield potential and in severely degradation means that the land has yield potential is lost more than 50% of its potential yield capacity (productive capacity).



  • Some causes of land degradation are: 

  • use of agrochemical (chemical fertilizers and pesticides)

  • excessive irrigation

  • cultivation of high yielding plant varieties.

  • Conservation of cultivable land cause can be achieved not only through preventive and remedial measures in order to control land erosion and degradation about which you will read in section 1but also by using innovative agricultural technologies which involve use of:

(i) organic farming or green manures 

(ii) biofertilisers

 (iii) biological pest control

  • The cottony cushion scale pest (Icerya pur cahsi) (Fig. 17.13a) is controlled biologically on a large scale by its predator, the lady bird beetle

  • Our ecological foot prints –the amount of biologically productive area of the earth needed to produce the required resources as well as to absorb the wastes produced from such resources use.

  • On his recommendation two semi dwarf varieties namely Lerma Rajo and Sonora-64 were chosen and were released for cultivation in irrigated fields. These varieties gave very high yield and brought in revolution in wheat production.

  • M.S. Swaminathan an outstanding mutation geneticist produced ‘Sharbati Sonara’ and released it for cultivation in 1967.

  • Dr . Borlaug :In 1970 he was awarded Nobel prize for “Green Revolution” which helped India.

  • Sustainable Agriculture is one that,

  • supports profitable production;  

  • protects environmental quality;

  • uses natural resources efficiently;  

  • provides consumers with affordable, high-quality products;

  • decreases dependency on non-renewable resources;

  • enhances the quality of life for farmers and rural communities;

  • and will last for generations to come.

  • Several methods adopted in sustainable agriculture are:

  • cultivation practices to increase biological and economic stability .

  • selection of improved varieties to suit the need.

  • soil management by proper method of tillage.

(a)  Mixed cropping or diverse cropping

  • The various plans followed in diverse or mixed cropping practices are-

  • Poly-varietal cultivation where several genetic varieties of the same crop are planted.

  • Inter-cropping where two or more different crops are grown at the same time on a plot

  • Polyculture, in which different plants maturing at various times are planted together .



(b)  Crop rotation

(i) Leguminous crop should be grown after non-leguminous crop

(ii) Crops require less water (irrigation) should be grown after one – that requires more water .

(iii) Crops requiring less manure should be sown after one that requires more manure

  • Important crop patterns of crop rotation

  1. Green gram – Wheat – Moong

  2. Ground nut – Wheat – Moong

  3. Arhar – Sugarcane – Wheat – Moong

  4. Paddy – Wheat – Moong

  • First, growing crops only on more level land and pastures or forages on steeper slopes will reduce soil erosion.

  • Second, pasture and leguminous forage crops in rotation enhance soil quality and reduce erosion; livestock manure, in turn, contributes to soil fertility .

  • Third, livestock can buffer the negative impacts of low rainfall periods by consuming crop residue that in “plant only” systems would have been considered crop failures.

  • Finally , feeding and marketing are flexible in animal production systems.




  • Radiation pollution is the increase in over the natural background radiation. There are many sources of radiation pollution such as nuclear wastes from nuclear power plants, mining and processing of nuclear material etc.

  • When a gamma ray passes through a cell, the water molecules near the DNA might be ionized and the ions might react with the DNA causing it to break. They can also cause chemical changes by breaking the chemical bonds, which can damage living tissues.

Radiation damage can be divided into two types: 

1)  Somatic damage (also called  radiation sickness) 

 Somatic damage refers to damage to cells that are not associated with reproduction. Effects of somatic radiation damage include reddening of the skin, loss of hair , ulceration, fibrosis of the lungs, the formation of holes in tissue, a reduction of white blood cells, and the induction of cataract in the eyes. This damage can also result in cancer and death. 

2) Genetic damage

Genetic damage refers to damage to cells associated with reproduction. This damage can subsequently cause genetic damage from gene mutation resulting in abnormalities. Genetic damages are passed on to next generation.

A traditional unit of human-equivalent dose is the  rem , which stands for  radiation equivalent in man.

At low doses, such as what we receive every day from background radiation (< 1  m rem), the cells repair the damage rapidly .  At higher doses (up to 100  rem), the cells might get mutated.

it is important to realize that the biological damage caused by a particle depends not only on the total energy deposited but also on the rate of energy loss per unit distance traversed by the particle (or “linear energy transfer”). For example, alpha particles do much more damage per unit energy deposited than do electrons.



  • Non-ionizing radiations are constituted by the electromagnetic waves at the longer wavelength of the spectrum ranging from near infra-red rays to radio waves.

  • These waves have energies enough to excite the atoms and molecules of the medium through which they pass, causing them to vibrate faster but not strong enough to ionize them.

  • In a microwave oven the radiation causes water molecules in the cooking medium to vibrate faster and thus raising its temperature.

  • Ionizing radiations  cause ionization of atoms and molecules of the medium through which they pass. Electromagnetic radiations such as short wavelength ultra violet radiations (UV)

  • X-rays and gamma rays and energetic particles produced in nuclear processes, electrically charged particles like alpha and beta particles produced in radioactive decay and neutrons produced in nuclear fission, are highly damaging to living organisms.



  1. Bacterial diseases:

  • Cholera- Vibrio cholerae

  1. Viral diseases

  • Hepatitis

  1. Protozoan diseases

  • Dysentery

  • Diarrhoea

  • Malaria- Plasmodium Vivax

  • Dengue caused by- Aedes aegypti– Man Sudden onset of moderately high fever, 

  • Asbestos, nickel, cadmium, radon, vinyl chloride, benzidine and benzene -carcinogens.

  • An allergic person’s immune system believes allergens to be damaging and so produces a special type of antibody immunoglobulin E (IgE) to attack the invading material. This leads other blood cells to release further chemicals (including histamine) which together cause the symptoms of an allergic reaction.

  • Blue Baby disease- Modern agriculture uses a lot of nitrogenous fertilizers and manures. This leads to increased levels of nitrates in the ground water as nitrates being soluble in water easily leach into the soil. Once the level exceeds 10 ppm it may become harmful and contaminate source of drinking water , this causes  methaemoglobinaemia( blue baby syndrome)  particularly in bottle fed infants who are very sensitive to this pollutant

  • When water containing nitrates is consumed and it reaches intestines, the intestinal bacteria convert nitrates into nitrites. The nitrite ions combine with haemoglobin to form methaemoglobin which inhibits the oxygen carrying capacity of the blood causing a kind of anaemia known as

  • Methaemoglobin is formed when iron in the haemoglobin molecule is oxidized from Fe 2 + (ferrous) to Fe 3 +  (ferric) form.

  • Nitrates can be removed from the water by processes like electrodialysis and reverse osmosis. Nitrites in the water can be oxidized to nitrates by introducing a strong oxidant like ozone in the water .



  • Heavy metals cannot be destroyed by biological degradation

  • Lead enters the atmosphere from automobile exhaust .It is a carcinogen of the lungs and kidneys

  • Mercury kills cells in the body and damages organs which come in contact with mercury and thus impairs their functioning. Inhalation of mercury vapors is more dangerous than its ingestion. Chronic exposure causes lesions in the mouth and skin and neurological problems.

  • Largest source of mercury pollution is through aquatic animals such as fish which accumulate mercury as methyl mercury .

  • Arsenic is emitted from fossil fuel burning. Liquid effluents from fertilizer plants also contain arsenic.



  • Chronic arsenic poisoning leads to loss of appetite, weight, diarrhoea, gastrointestinal disturbances and skin cancer .

  • Alternatively the tube well/ hand pump water should be purified to remove arsenic before consumption

  • If a person drinks water contaminated with arsenic for about 10 years, dark spot develop on the upper chest, back and arms known as The next stage is keratosis in which palms become hard and patient may suffer from diarrohea, stomach pain, breathing problems, etc. 

  • Mining especially of zinc and metallurgical operations, electroplating industries, etc. release cadmium in the environment. It may enter the human body by inhalation or from aquatic sources including fish, etc. It may cause hypertension, liver cirrhosis, brittle bones, kidney damage and lung cancer . Itai-itai disease first reported from Japan in 1965 was attributed to cadmium contamination in water and rice

  • Metals such as zinc, chromium, antimony and tin enter food from cheap cooking utensils. Preserved foods stored in tin cans also cause contamination by tin.

  • Black lung disease is the common name for pneumoconiosis (CWP) or anthracosis, a lung disease of older workers in the coal industry , caused by inhalation over many years, of small amounts of coal dust.

  • Silicosis first reported from Kolar gold mines in 1947 is a common disease among miners, pottery and ceramic industry workers.

  • Pneumoconiosis & byssinosis are common among mica and textile industry workers respectively .

  • Floods are caused by rains, high winds, cyclones, tsunami, melting snow or dam burst.

  • Effects

  • Casualties

  • Structural damage :During floods mud huts and buildings built on weak foundations collapse endangering human lives and property . Damage may also cause to roads, rail, dams, monuments

  • Material loss

  • Utilities damage :Utilities such as water supply , sewerage, communication lines, power -lines, transportation network and railways are put at risk.

  • Crop loss

  • Dengue is also called Breakbone Fever, or Dandy Fever. It is an acute, infectious, mosquito- borne hemorrhagic fever.

  • Dengue is caused by a virus transmitted through a mosquito called Aedes aegypti or Asian tiger mosquito.

  • Water on earth is classified into following three types:

  1. a) Fresh water: It is inland water and its salt content is less than 5 ppt or 0.5%;

  2. b) Marine water: It occurs in seas, oceans and its salt content is more than 35 ppt or 3.5%.

  3. c) Brackish water: It’ s salt content is more than 5 ppt but less than 35ppt. It is present in estuaries, salt marshes and salt lakes. A lot of underground water in Rajasthan, Gujarat, Haryana and Punjab is brackish

  • The ultimate source of this water is rainfall. India receives about 2750 km of rainfall per year .  About 600 km  of its seeps into the ground and about 900 km 3 evaporates water vapour back into environment. 



  • Nitrogen oxides (N 2 O)— Burning of fossil fuels, fertilizers; burning of wood and crop residue.

  • Biodiversity could be classified as

(a) Species biodiversity: It includes total number of different taxonomical or biological species. There are more than 200000 species in India of which several are confined to India (endemic).

  • (b) Genetic biodiversity: It includes land traces; horticultural varieties; cultivers, ecotypes (related types differing due to difference in the ecological condition); all within a biological species.

(c) Ecosystem biodiversity: It includes various biological zones, like lake, desert, coast, estuaries, wetlands, mangroves, coral reefs etc

  • A high value fish is the one which is captured  prior to completing its  life cycle.

  • Ultra violet (UV) radiation, with wavelengths shorter than visible spectrum has high energy . UV  radiations can be divided into three forms: 

  • UV-A (wavelength between 320-400nm), 

  • UV-B (wave length lesser than 280  nm), and 

  • UV-C (wavelength lesser than 280 nm).  UV-C is most damaging to biological systems.





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