Environment Ecology BYJU Notes[Shashidthakur23.Wordpress.com]

ENVIRONMENT & ECOLOGY - 1

CONCEPT OF SYSTEM:

System is group or sum assemblage of elements (can be called subsystem), interacting or independent with each other and separated from space around it (can be called surrounding or its environment) by a boundary (has to be defined by the observer). The concept came into existence for explaining or studying the behavior of a complex element in a scientific and rational manner, however it as good for the simple elements.

Therefore in simple words a system could be defined as: • A set of inter-related components (What it is) • Operates collectively (How it operates) • To accomplish common goals (Its purpose)

And SYSTEMS ENVIRONMENT can be defined as:

• Elements surrounding the system • That are outside the system and interact with the system

And based upon the interaction between the system and its environment, a system can be classified into:

• Closed System, i.e. No interaction of any nature • Open System, i.e. Interaction exits between environment

and the system

Note: In environmental studies most of the systems are of open nature and are thus complex.

UNDERSTANDING THE ECOSYSTEM:

The living community of plants and animals in any area together with the non-living components of the environment such as soil, air, climate, landform and water, constitute the ecosystem. The ecosystem is the unit and way of study of Ecology (i.e. Study of home of living species).

In other words, any system which constitutes of living community and non-living community functioning through various cycles can be called an ecosystem.

Therefore an ‘Ecosystem’ is a region with a specific and recognizable landscape form such as forest, grassland, desert, wetland or coastal area.

The nature of the ecosystem is based on its geographical features such as hills, mountains, plains, rivers, lakes, coastal areas or islands.

It is also controlled by climatic conditions such as the amount of sunlight, the temperature and the rainfall in the region. The geographical, climatic and soil characteristics form its non-living (abiotic) component.

These features create conditions that support a community of plants and animals that evolution has produced to live in these specific conditions. The living part of the ecosystem is referred to as its biotic component.


Structural aspects of an ecosystem: Components that make up the structural aspects of an ecosystem include: 1. Inorganic aspects – C, N, CO2, H2O 2. Organic compounds – Protein, Carbohydrates, Lipids (link abiotic to biotic aspects) 3. Climatic regimes – Temperature, Moisture, Light & Topography 4. Producers – Plants 5. Macro consumers – Phagotrophs – Large animals 6. Micro consumers – Saprotrophs, absorbers – fungi

Functional aspects of an ecosystem (what an ecosystem actually does):-

1. Energy cycles 2. Food chains 3. Diversity - interlinkages between organisms 4. Nutrient cycles - biogeochemical cycles, e.g. Water cycle, Carbon cycle, Nitrogen cycle, Oxygen cycle 5. Evolution

Therefore an ecosystem can be as small as the hole of ants and can be as large as the thin skin of the earth

on the land, the sea and the air, called the biosphere (global level), which is realm of earth and its atmosphere where life can be found, so it depends upon the area of interest of the observer and hence classified thus.

But on a broad scale or division, ecosystems are divided into terrestrial or land-based ecosystems, and aquatic ecosystems in water.

These form the two major habitat conditions for the Earth’s living organisms. At a sub-global level, this is divided into bio-geographical realms, e.g. Eurasia called the palaeartic realm;

South and South-East Asia (of which India forms a major part) is the Oriental realm; North America is the Nearctic realm; South America forms the Neotropical realm; Africa the Ethiopian realm; and Australia the Australian realm.

At a national or state level, this forms bio-geographic regions. There are several distinctive geographical regions in India - the Himalayas, the Gangetic Plains, the

Highlands of Central India, the Western and Eastern Ghats, the semi-arid desert in the West, the Deccan Plateau, the Coastal Belts, and the Andaman and Nicobar Islands.

These geographically distinctive areas have plants and animals that have been adapted to live in each of these regions.

At an even more local level, each area has several structurally and functionally identifiable eco-systems systems such as different types of forests, grass-lands, river catchments, mangrove swamps in deltas, seashores, islands, etc. to give only a few examples. Here too each of these forms a habitat for specific plants and animals.

Amongst the various cycles operating at an ecosystem level, one of the most important cycle is Energy cycle and concepts associated with it.

ENERGY CYCLE The energy cycle is based on the flow of energy through the ecosystem. The main source of energy to an

ecosystem is Sun’s energy which is converted into bio-mass energy by Producers i.e. plants. The energy in the ecosystem can be depicted in the form of a food pyramid or energy pyramid. The food pyramid has a large base of plants called ‘producers’. The pyramid has a narrower middle section

that depicts the number and bio-mass of herbivorous animals, which are called ‘first order consumers first order consumers’.


The apex depicts the small biomass of carnivorous animals called ‘second order consumers’. Man is one of the animals at the apex of the pyramid. Thus to support mankind, there must be a large base

of herbivorous animals and an even greater quantity of plant material. When plants and animals die, this material is returned to the soil after being broken down into simpler

substances by decomposers such as insects, worms, bacteria and fungi so that plants can absorb the nutrients through their roots.

Meaning of the term ‘Food Chains’, ‘Food Web’, ‘Trophic Level’ and ‘Ecological Pyramid’ The most obvious aspect of nature is that energy must pass from one living organism to another. When

herbivorous animals feed on plants, energy is transferred from plants to animals. In an ecosystem, some of the animals feed on other living organisms, while some feed on dead organic matter. At each linkage in the chain, a major part of the energy from the food is lost for daily activities. Each chain

usually has only four to five such links. However a single species may be linked to a large number of species. This transfer of energy from the source in plants through a series of organisms by eating and being eaten

constitutes food chains. These food chains are not isolated sequences, but are interconnected with each other and this interlocking

pattern is known as the food web. In an ecosystem there are a very large number of interlinked chains. This forms a food web. If the linkages in

the chains that make up the web of life are disrupted due to human activities that lead to the loss or extinction of species, the web breaks down.

Each step of the food web is called a trophic level. Hence green plants occupy the first level, herbivores the second level, carnivores the third level and secondary carnivores the fourth level.


These trophic levels together form the ecological pyramid. At each transfer, a large proportion of energy is lost in the form of heat.

ECOLOGICAL SUCCESSION Ecological succession is a process through which ecosystems tend to change over a period of time.

Succession can be related to seasonal environmental changes, which create changes in the community of plants and animals living in the ecosystem. Other successional events may take much longer periods of time extending to several decades.

There is a tendency for succession to produce a more or less stable state at the end of the successional stages.

Developmental stages in the ecosystem thus consist of a pioneer stage, a series of changes known as serel stages, and finally a climax stage.

The most frequent example of successional changes occur in a pond ecosystem where it fluctuates from a dry terrestrial habitat to the early colonization stage by small aquatic species after the monsoon, which gradually passes through to a mature aquatic ecosystem, and then reverts back to its dry stage in summer where its aquatic life remains dormant.


‘Biological diversity’ or biodiversity is that part of nature which includes the differences in genes among the individuals of a species, the variety and richness of all the plant and animal species at different scales in space, locally, in a region, in the country and the world, and various types of ecosystems, both terrestrial and aquatic, within a defined area.

Biological diversity deals with the degree of nature’s variety in the biosphere. This variety can be observed at three levels:

1. The genetic variability within a species, 2. The variety of species within a community, and 3. The organization of species in an area into distinctive plant and animal com-munities constitutes

ecosystem diversity

Genetic diversity: Each member of any animal or plant species differs widely from other individuals in its genetic makeup

because of the large number of combinations possible in the genes that give every individual specific characteristic.

Thus, for example, each human being is very different from all others. This genetic variability is essential for a healthy breeding population of a species.

If the number of breeding individuals is reduced, the dissimilarity of genetic makeup is reduced and in-breeding occurs. Eventually this can lead to the extinction of the species.

The diversity in wild species forms the ‘gene pool’ from which our crops and domestic animals have been developed over thousands of years.

Species diversity: The number of species of plants and animals that are present in a region constitutes its species diversity.

This diversity is seen both in natural ecosystems and in agricultural ecosystems. Some areas are richer in species than others.

Natural undisturbed tropical forests have much greater species richness than plantations developed by the Forest Department for timber production.

Modern intensive agricultural ecosystems have a relatively lower diversity of crops than traditional agro-pastoral farming systems where multiple crops were planted.

Areas that are rich in species diversity are called ‘hotspots’ of diversity. India is among the world’s 15 nations that are exceptionally rich in species diversity.

Ecosystem diversity: There are a large variety of different ecosystems on earth, which have their own complement of

distinctive inter linked species based on the differences in the habitat. Ecosystem diversity can be described for a specific geographical region, or a political entity such as a

country, a State or a taluka. Distinctive ecosystems include landscapes such as forests, grasslands, deserts, mountains, etc., as well

as aquatic ecosystems such as rivers, lakes, and the sea. Each region also has man-modified areas such as farmland or grazing pastures. An ecosystem is referred

to as ‘natural’ when it is relatively undisturbed by human activities or ‘modified’ when it is changed to other types of uses, such as farmland or urban areas. Ecosystems are most natural in wilderness areas.


VALUE OF BIODIVERSITY: 1. Consumptive use value 2. Productive use value 3. Social values (While traditional societies which had a small population and required less resources had

pre-served their biodiversity as a life supporting resource, modern man has rapidly depleted it even to the extent of leading to the irrecoverable loss due to extinction of several species. Thus apart from the local use or sale of products of biodiversity there is the social aspect in which more and more resources are used by affluent societies. The biodiversity has to a great extent been preserved by traditional societies that valued it as a resource and appreciated that its depletion would be a great loss to their society)

4. Ethical and moral values (Don’t plants and animals have an equal right to live and exist on our planet which is like an inhabited spaceship?)

5. Aesthetic value 6. Option value (Keeping future possibilities open for their use is called option value. It is impossible to

predict which of our species or traditional varieties of crops and domestic animals will be of great use in the future)

Commonly used modern drugs derived from plant sources:

SL No. DRUG PLANT SOURCE USE

1 Atropine Belladonna Anticholinergic - reduces intestinal pain in diarrhea.

2 Bromelain Pineapple Controls tissue inflammation due to infection

3 Caffeine Tea, Coffee Stimulant of the central nervous system.

4 Camphor Camphor tree Rebefacient - increases local blood supply

5 Cocaine Cocoa Analgesic and local anesthetic

6 Codeine Opium poppy Analgesic - reduces pain

7 Morphine Opium poppy Analgesic - controls pain

8 Colchicine Autumn crocus Anticancer agent

9 Digitoxin Common foxglove Cardiac stimulant used in heart diseases

10 Diosgenin Wild yams Source of female contraceptive - prevents pregnancy

11 L-Dopa Velvet bean Controls Parkinson’s Disease

12 Ergotamine Smut-of-rye or ergot Control of hemorrhage and migraine headaches

13 Glaziovine ocotea glaziovii Antidepressant - Elevates mood of depressed patients

14 Gossypol Cotton Male contraceptive

15 Indicine N-oxide heliotropium indicum Anticancer agent

16 Menthol Mint Rubefacient - Increases local blood supply & reduces pain

17 Monocrotaline Cotolaria sessiliflora Anticancer agent

18 Papain Papaya Dissolves excess protein and mucus, during digestion

19 Penicillin Penicillium fungi General antibiotic

20 Quinine Yellow cinochona Antimalarial

21 Reserpine Indian snakeroot Reduces high blood pressure

22 Scopolamine Thorn apple Sedative

23 Taxol Pacific yew Anticancer (ovarian).

24 Vinblastine Rosy periwinkle Anticancer agent - Controls cancer in children.


ENDEMIC SPECIES Some species of plants and animals are extremely rare and may occur only at a few locations. These are said to be ‘endemic’ to these areas. It is estimated that 18% of Indian plants are endemic to the country and found nowhere else in the

world. E.g. Indian Wild Ass, Gharial etc.

EXOTIC SPECIES The exotic species are those which are not a part of the natural vegetation. Common examples in India are lantana bushes, Eupatorium shrubs and ‘congress’ grass. These have been imported into the country from abroad and have invaded several large tracts of our

natural forests. Another factor that disrupts forest biodiversity is the introduction of such exotic species.

Environment and Ecology - 3

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ENDEMIC SPECIES & Their REGIONS:

1. Hangul Deer: Kashmir 2. Barasingha or Swamp Deer: Tarai Region 3. Nilgiri Tahr: Shola Grassland 4. Indian Wild Ass: Little Runn of Kutch 5. Snow Leopard: Himalayas (found in Great Himalayan National Park) 6. Asiatic Lion: Gir forest region of Gujrat 7. Lion tail Macaque: Western Ghats and Annamalai regions 8. Golden Langur: Manas region in Assam 9. Black Langur: Nilgiri region 10. Great Indian Bustard: Semi - Arid region of Rajasthan

CONSERVATION OF BIODIVERSITY: IN-SITU AND EX-SITU

1. In-Situ Conservation- Conservation of a species is best done by protecting its habitat along with all the other species that live in it in nature. This is known as in-situ conservation, which is conserving a species in its own environment by creating National Parks and Wildlife Sanctuaries. i.e. Conservation of wild life in their natural place itself. e.g. Wildlife sanctuary, National Park, Biosphere reserve.

2. Ex-Situ Conservation – When there are situations in which an endangered species is so close to extinction that unless alternate methods are instituted, the species may be rapidly driven to extinction. This strategy is known as ex-situ conservation, i.e. outside its natural habitat in a carefully controlled situation such as a botanical garden for plants or a zoological park for animals, where there is expertise to multiply the species under artificially managed conditions. These breeding programs for rare plants and animals are however more expensive than managing a Protected Area.

There is also another form of preserving a plant by preserving its germ plasm in a gene bank so that it can be used if needed in future.

Wildlife Sanctuaries and National Park:

This Provision having wildlife sanctuaries and National park was brought by a regulation in the year 1972 under Wildlife Conservation Act of 1972.

In India around 500 Wildlife Sanctuaries & 89 National park are present. Wildlife Sanctuaries are designated by the State Legislature and national parks are created by Union government.

Biosphere Reserve:

This concept was propagated by UNESCO in the year 1971 when they started the Program called ‘Man and the Biosphere Program’ (MAB).

Biosphere Reserve came into India through Environment Protection Act of 1986. Currently there are 18 Biosphere Reserves in India.

Biosphere Reserves:- 1. The Great Run of Kutch 2. Simlipal (Orissa) 3. The Gulf of Mannar 4. Amarkantak 5. Sunder bans 6. Manas (Assam) 7. Cold Desert in Ladakh 8. Kanchenjunga (Sikkim) 9. The Nanda Devi 10. Agastya Mala (Trivandrum) 11. The Nilgiris (Oldest Reserve) 12. Great Nicobar 13. Dehang Debang 14. Nokrek 15. Pachmarhi 16. Dibru Saikhowa 17. Seshachalam 18. Panna


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7 of them which have been recognized by UNESCO under MAB Program are: Nilgiris, Sunder bans, Gulf of Mannar, Nanda Devi, Nokrek, Simlipal and Pachmarhi.

National Legislations on the Environment

Constitutional provisions:

Forty Second Amendment in the Constitution of India, 1976 has introduced Articles 48A and 5 1A (g) which form Directive Principles of State Policy and the Fundamental Duties respectively. The Supreme Court referred to the concept of ‘Sustainable Development' and 'Polluter pays' principle and held that right to healthy environment is a part and parcel of 'right to life’ guaranteed under article 21 (fundamental rights) of the Constitution. The Supreme Court in its judgment Chameli Singh v. State of U.P. held that Article 21 includes right to food, water, decent environment, medical care shelter and education.

Article -48A: Protection and improvement of environment and safeguarding of forests and wild life: The State shall endeavor to protect and improve the environment and to safeguard the forests and wild life of the country.

Article -51A(g): It is the fundamental duty of Indian citizens to protect and improve the natural environment including forests, lakes, rivers and wild life, and to have compassion for living creatures;

Statutory Acts:

1. Wildlife Conservation Act of 1972: It refers to a sweeping package of legislation enacted in 1972 by the Government of India. Among other reforms, the Act established schedules of protected plant and animal species; hunting or harvesting these species was largely outlawed. The Act provides for the protection of wild animals, birds and plants; and for matters connected therewith or ancillary or incidental thereto. It extends to the whole of India, except the State of Jammu and Kashmir which has its own wildlife act. It also provides for declaration of an area as Wildlife sanctuaries by states and National parks by the central government.

2. Environment (Protection) Act of 1986: The Environment (Protection) Act, 1986 not only has important constitutional implications but also an international background. The spirit of the proclamation adopted by the United Nations Conference on Human Environment which took place in Stockholm in June 1972 was implemented by the Government of India by creating this Act.

The Act to provide for the protection and improvement of environment and for matters connected there with; to take appropriate steps for the protection and improvement of human environment; AND WHEREAS it is considered necessary further to implement the decisions aforesaid in so far as they relate to the protection and improvement of environment and the prevention of hazards to human beings, other living creatures, plants and property;

Although there were several existing laws that dealt directly or indirectly with environmental issues, it was necessary to have a general legislation for environmental protection because the existing laws focused on very specific types of pollution, or specific categories of hazardous substances or were indirectly related to the environment through laws that control land use, protect our National Parks and Sanctuaries and our wildlife. However there was no overarching legislation and certain areas of environmental hazards were not covered. There were also gaps in areas that were potential environmental hazards and there were several inadequate linkages in handling matters of industrial and environmental safety. This was essentially related to the multiplicity of regulatory agencies. Thus


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there was a need for an authority which could assume the lead role for studying, planning and implementing long term requirements of environmental safety and give directions to, as well as coordinate a system of speedy and adequate response to emergency situations threatening the environment. This Act for the first time conferred enforcement agencies with necessary punitive powers to restrict any activity that can harm the environment.

3. Forest Conservation Act of 1980: To appreciate the importance of the Forest Conservation Act of

1980, which was amended in 1988, it is essential to understand its historical background. The Indian Forest Act of 1927 consolidated all the previous laws regarding forests that were passed before the 1920’s. The Act gave the Government and Forest Department the power to create Reserved Forests, and the right to use Reserved Forests for Government use alone. It also created Protected Forests, in which the use of resources by local people was controlled. Some forests were also to be controlled by a village community, and these were called Village Forests.

The Act remained in force till the 1980s when it was realized that protecting forests for timber production alone was not acceptable. The other values of protecting the services that forests provide and its valuable assets such as biodiversity began to overshadow the importance of their revenue earnings from timber. Thus a new Act was essential. This led to the Forest Conservation Act of 1980 and its amendment in 1988.

The Forest Conservation Act of 1980 was enacted to control deforestation which was massive between 1952 and 1988. It ensured that forestlands could not be de-reserved without prior approval of the Central Government. This was created as States had begun to de-reserve the Reserved Forests for non-forest use. States had regularized encroachments and resettled ‘Project Affected People’ from development projects such as dams in these de-reserved areas. The need for a new legislation became urgent. The Act made it possible to retain a greater control over the frightening level of deforestation in the country and specified penalties for offenders.

4. THE WATER (PREVENTION AND CONTROL OF POLLUTION) ACT: The Government has formulated this

Act in 1974 to be able to prevent pollution of water by industrial, agricultural and household wastewater that can contaminate our water sources. The main objectives of the Water Act are to provide for prevention, control and abatement of water pollution and the maintenance or restoration of the wholesomeness of water. It is designed to assess pollution levels and punish polluters. The Central Government and State Governments have set up Pollution Control Boards that monitor water pollution.

5. THE AIR (PREVENTION AND CONTROL OF POLLUTION) ACT: The Government passed this Act in 1981 to clean up our air by controlling pollution. Sources of air pollution such as industry, vehicles, power plants, etc. are not permitted to release particulate matter, lead, carbon monoxide, sulfur dioxide, nitrogen oxide, volatile organic com-pounds (VOCs) or other toxic substances beyond a prescribed level. The main objectives of the Act are as follows: I. To provide for the Prevention, Control and abatement of air pollution.

II. To provide for the establishment of Central and State Boards with a view to implement the Act. III. To confer on the Boards the powers to implement the provisions of the Act and assign to the

Boards functions relating to pollution.


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INTERNATIONAL CONFERENCES, ENVIRONMENTAL ISSUES AND PROTOCOLS:

United Nation Conference on the Human Environment -1972:

The first United Nations Conference on the Human Environment (UNCHE) was held in Stockholm, Sweden from June 5 to June 16, 1972.

This was the first United Nations conference on the environment as well as the first major international gathering focused on human activities in relationship to the environment, and it laid the foundation for environmental action at an international level.

The conference acknowledged that the goal of reducing human impact on the environment would require extensive international cooperation, as many of the problems affecting the environment are global in nature.

Following this conference, the United Nations Environmental Programme (UNEP) was launched in order to encourage United Nations agencies to integrate environmental measures into their programs.

One of the greatest achievements of the UNCHE was the creation of the United Nations Environment Programme (UNEP), based in Nairobi, Kenya.

The mission of UNEP is "to provide leadership and encourage partnership in caring for the environment by inspiring, informing, and enabling nations and peoples to improve their quality of life without compromising that of future generations." UNEP is the voice for the environment within the United Nations system and works toward this mission by:

Encouraging international participation and cooperation in addressing environmental issues and environmental policy

Monitoring the status of the global environment and interpreting environmental data collected

Creating environmental awareness in governments, society, and the private sector

Coordinating UN activities pertaining to the environment

Developing regional programs for sustainability

Helping environmental authorities, especially those in developing countries, form and implement policy

Helping to develop international environmental law

Major Global Environmental Issues are: 1. Ozone hole 2. Climate change

a. Global warming b. Desertification c. Conservation of Biodiversity

Ozone Hole: Ozone is a compound (O3) which is a derivative of environment oxygen. The ozone layer is mainly

found in the lower portion of the stratosphere from approximately 20 to 30 kilometers (12 to 19 mi) above Earth, though the thickness varies seasonally and geographically.

This ozone layer absorbs the ultraviolet radiation which is emitting from the Solar system. Factors responsible for Ozone hole Depletion are the manmade compounds called Chlorofluorocarbons (CFC).

The ozone layer can be depleted by free radical catalysts, including nitric oxide (NO), nitrous oxide (N2O), hydroxyl (OH), atomic chlorine (Cl), and atomic bromine (Br).

While there are natural sources for all of these species, the concentrations of chlorine and bromine have increased markedly in recent years due to the release of large quantities of man-


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made organohalogen compounds, especially chlorofluorocarbons (CFCs) and bromofluorocarbons.

Chlorofluorocarbons are used in different kind of Aerosols & Coolant in the radiators. Effects of Ozone hole on Human:

o Exposure to Ultraviolet rays causes Skin Cancer o Excess Vitamin D o Skin burns on animals occurs o Cataract

Global efforts for the depletion of Ozone hole:

Montreal Protocol -1987: 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 believed to

be responsible for ozone depletion.

Climate Change

Global Warming: A general increase in temperature of the atmosphere of the earth due to human activities is called global warming. The most important summit to prevent this was Earth Summit Conference held at Rio de Janeiro on 1992. After 20 years in 2012 the Rio+20 summit was also organized in Rio de Janeiro. Earth Summit: This Summit leads to the formation of 3 very important conventions:

I. UNFCC - The United Nations Framework Convention on Climate Change II. UNCBD/CBD - The United Nations Convention on Biological Diversity

III. UNCCD - The United Nations Convention to Combat Desertification

I. UNFCC- United Nations Framework Convention on Climate Change

UNFCC is mainly deals with concept of the climate change

This convention is mainly based on 2 major principles

o CBDI -Common But Differentiated Responsibility

o Equity

The different Conference of UNFCC is COP- Conference of Parties. The first COP-1 is held at Berlin in

1995 which led to the signing of UNFCC document by all member nations. The COP-3 occurred in 1997 at

Kyoto in Japan which led to the creation of Kyoto protocol.

Kyoto Protocol divides the countries into 2 groups: I. Annexe 1 Countries: This Contains 37 Industrialized Nations of the world. These countries have

the Historical Responsibility. Target given by the Kyoto protocol in 1990 to Annexe 1 countries have to bring down the Carbon dioxide level by 5.2% by the year 2012.

II. Non-Annexe 1 countries


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In 2001 COP-7 was held at Marrakesh in Morocco. Marrakesh Accord is the very important steps for Kyoto protocol. It also provided different mechanism for develop & developed countries. This mechanism is known as flexible mechanism. Flexible Mechanism includes:

1. Emissions trading: Carbon Credit or CER (Certified Emissions Reduction) under Offset trading 2. Clean Development Mechanism (CDM) 3. Joint Implementation (JI)

COP-15 which occurred in the year 2010 at a place called Copenhagen in Denmark. This lead to creation

3 new concepts:

1. Green Climate Fund (GCF)

2. Adaptation Framework

3. Technology Mechanism


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Climate Change

Climate change means a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods

Climate Change and its implications for India: The future impacts of climate change, identified by the Government of India include:

Decreased snow cover, affecting snow-fed and glacial systems such as the Ganges and Brahmaputra. 70% of the summer flow of the Ganges comes from melt water

Erratic monsoon with serious effects on rain-fed agriculture, peninsular rivers, water and power supply

Drop in wheat production by 4-5 million tones, with even a 1ºC rise in temperature

Rising sea levels causing displacement along one of the most densely populated coastlines in the world, threatened freshwater sources and mangrove ecosystems

Increased frequency and intensity of floods. Increased vulnerability of people in coastal, arid and semi-arid zones of the country

Studies indicate that over 50% of India’s forests are likely to experience shift in forest types, adversely impacting associated biodiversity, regional climate dynamics as well as livelihoods based on forest products.

Response to Climate Change: There are two main policy responses to climate change:

Mitigation

Adaptation Mitigation addresses the root causes, by reducing greenhouse gas emissions, while adaptation seeks to lower the risks posed by the consequences of climatic changes. Both approaches will be necessary, because even if emissions are dramatically decreased in the next decade, adaptation will still be needed to deal with the global changes that have already been set in motion. Adaptation measures may be planned in advance or put in place spontaneously in response to a local pressure. They include large-scale infrastructure changes – such as building defenses to protect against sea-level rise or improving the quality of road surfaces to withstand hotter temperatures – as well behavioral shifts such as individuals using less water, farmers planting different crops and more households and businesses buying flood insurance. The IPCC describes vulnerability to climate change as being determined by three factors: exposure to hazards (such as reduced rainfall), sensitivity to those hazards (such as an economy dominated by rain-fed agriculture), and the capacity to adapt to those hazards (for example, whether farmers have the money or skills to grow more drought-resistant crops). Adaptation measures can help reduce vulnerability – for example by lowering sensitivity or building adaptive capacity – as well as allowing populations to benefit from opportunities of climatic changes, such as growing new crops in areas that were previously unsuitable. Low-income countries tend to be more vulnerable to climate risks and some adaptation measures – such as increasing access to education and health facilities – will overlap with existing development programmes. But adaptation goes beyond just development to include measures to address additional risks specifically caused by climate change, such as raising the height of sea defenses. It is still unclear how expensive these measures


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will be or who will pay for them, but the World Bank suggests adaptation could cost the same again as the world currently spends on development assistance. Indian response to Climate Change: NATIONAL ACTION PLAN ON CLIMATE CHANGE (NAPCC)

On June 30, 2008, Prime Minister Manmohan Singh released India’s first National Action Plan on Climate Change (NAPCC) outlining existing and future policies and programs addressing climate mitigation and adaptation.

The plan identifies eight core “national missions” running through 2017 and directs ministries to submit detailed implementation plans to the Prime Minister’s Council on Climate Change.

Emphasizing the overriding priority of maintaining high economic growth rates to raise living standards, the plan “identifies measures that promote our development objectives while also yielding co-benefits for addressing climate change effectively.”

It says these national measures would be more successful with assistance from developed countries, and pledges that India’s per capita greenhouse gas emissions “will at no point exceed that of developed countries even as we pursue our development objectives.”

National Missions

National Solar Mission: The NAPCC aims to promote the development and use of solar energy for power generation and other uses with the ultimate objective of making solar competitive with fossil-based energy options. The plan includes:

Specific goals for increasing use of solar thermal technologies in urban areas, industry, and commercial establishments;

Produce 22,000 Megawatts of Solar Energy by the year 2022.

A goal of increasing production of photovoltaic to 1000 MW/year; and

A goal of deploying at least 1000 MW of solar thermal power generation. Other objectives include the establishment of a solar research center, increased international collaboration on technology development, strengthening of domestic manufacturing capacity, and increased government funding and international support.

National Mission for Enhanced Energy Efficiency: Current initiatives are expected to yield savings of 10,000 MW by 2012. Building on the Energy Conservation Act 2001, the plan recommends:

Mandating specific energy consumption decreases in large energy-consuming industries, with a system for companies to trade energy-savings certificates;

Energy incentives, including reduced taxes on energy-efficient appliances; and

Financing for public-private partnerships to reduce energy consumption through demand-side management programs in the municipal, buildings and agricultural sectors.

National Mission on Sustainable Habitat: To promote energy efficiency as a core component of urban planning, the plan calls for:

Extending the existing Energy Conservation Building Code;

A greater emphasis on urban waste management and recycling, including power production from waste;

Strengthening the enforcement of automotive fuel economy standards and using pricing measures to encourage the purchase of efficient vehicles; and


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Incentives for the use of public transportation. National Water Mission: With water scarcity projected to worsen as a result of climate change, the plan sets a goal of a 20% improvement in water use efficiency through pricing and other measures. National Mission for Sustaining the Himalayan Ecosystem: The plan aims to conserve biodiversity, forest cover, and other ecological values in the Himalayan region, where glaciers that are a major source of India’s water supply are projected to recede as a result of global warming. National Mission for a “Green India”: Goals include the afforestation of 6 million hectares of degraded forest lands and expanding forest cover from 23% to 33% of India’s territory. National Mission for Sustainable Agriculture: The plan aims to support climate adaptation in agriculture through the development of climate-resilient crops, expansion of weather insurance mechanisms, and agricultural practices. National Mission on Strategic Knowledge for Climate Change: To gain a better understanding of climate science, impacts and challenges, the plan envisions a new Climate Science Research Fund, improved climate modeling, and increased international collaboration. It also encourage private sector initiatives to develop adaptation and mitigation technologies through venture capital funds.

Other Programs The NAPCC also describes other ongoing initiatives, including:

Power Generation: The government is mandating the retirement of inefficient coal-fired power plants and supporting the research and development of IGCC and supercritical technologies.

Renewable Energy: Under the Electricity Act 2003 and the National Tariff Policy 2006, the central and the state electricity regulatory commissions must purchase a certain percentage of grid-based power from renewable sources.

Energy Efficiency: Under the Energy Conservation Act 2001, large energy-consuming industries are required to undertake energy audits and an energy labeling program for appliances has been introduced.

POLLUTION Definition: Pollution is the effect of undesirable changes in our surroundings that have harmful effects on plants, animals and human beings. Pollutants: Pollutants include solid, liquid or gaseous sub-stances present in greater than natural abun-dance produced due to human activity, which have a detrimental effect on our environment. From an ecological perspective pollutants can be classified as follows:

1. Degradable or non-persistent pollutants: These can be rapidly broken down by natural processes. Eg: domestic sewage, discarded vegetables, etc.

2. Slowly degradable or persistent pollutants: Pollutants that remain in the environment for many years in an unchanged condition and take decades or longer to degrade. Eg: DDT, Endosulfan which is POP (Persistent Organic Pollutant) and most plastics.


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3. Non-degradable pollutants: These cannot be degraded by natural processes. Once they are released into the environment they are difficult to eradicate and continue to accumulate. Eg: toxic elements like lead or mercury

Pollution can be further categorized into:

Soil Pollution

Air Pollution

Water Pollution

Marine Pollution

Noise Pollution

Thermal Pollution

Nuclear Hazards SOIL POLLUTION There are 4 different layers of soils on surface of the Earth:

1. O-Horizon - The top layer or the surface litter layer called the O horizon consists mostly of freshly fallen and partially decomposed leaves, twigs, animal waste, fungi and other organic materials. Normally it is brown or black.

2. Horizon or Top soil- The uppermost layer of the soil called the A horizon consists of partially decomposed organic matter (humus) and some inorganic mineral particles. It is usually darker and looser than the deeper layers. The roots of most plants are found in these two upper layers.

3. Horizon or Sub soil: The B horizon often called the subsoil contains less organic material and fewer organisms than the A horizon.

4. Horizon - It contains weathered parent materials. This parent material does not contain any organic materials.

Causes of soil degradation:

1. Erosion

a. Gully erosion

b. Sheet erosion

2. Excess use of fertilizers AND pesticides

Pesticides

Insecticides Fungicide Rodenticide Herbicide

Some specific problems associated with the use of pesticides:

Bioaccumulation:

Persistent pesticides may also accumulate in the bodies of animals, and over a period of time increase in

concentration if the animal is unable to flush them out of its system thus leading to the phenomenon

called bioaccumulation.

Biomagnifications:


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When an affected animal is eaten by another carnivore these pesticides are further concentrated in the

body of the carnivore. This phenomenon of acquiring increasing levels of a substance in the bodies of

higher trophic level organisms is known as bio-magnification. This process especially in the case of

insecticide like DDT has been proved to be disastrous. DDT is a well known case of bio-magnification in

ecosystems.

3. Excess salts and water

WATER POLLUTION Definition: When the quality or composition of water changes directly or indirectly as a result of man’s activities such that it becomes unfit for any purpose it is said to be polluted. Point sources and Non-point sources of pollution: When a source of pollution can be readily identified because it has a definite source and place where it enters the water it is said to come from a point source. Eg. Municipal and Industrial Discharge Pipes. When a source of pollution cannot be readily identified, such as agricultural runoff, acid rain, etc, they are said to be non-point sources of pollution.

Causes of water pollution are:

1. Disease-causing agents (pathogens): which include bacteria, viruses, protozoa and parasitic worms that enter water from domestic sewage and untreated human and animal waste. Human wastes contain concentrated populations of coliform bacteria such as Escherichia coli and Streptococcus faecalis. These bacteria normally grow in the large intestine of humans where they are responsible for some food digestion and for the production of vitamin K. These bacteria are not harmful in low numbers. Large amounts of human waste in water, increases the number of these bacteria which cause gastrointestinal diseases. Other potentially harmful bacteria from human wastes may also be present in smaller numbers.

2. Oxygen depleting wastes: These are organic wastes that can be decomposed by aerobic (oxygen requiring) bacteria. Large populations of bacteria use up the oxygen present in water to degrade these wastes. In the process this degrades water quality. The amount of oxygen required to break down a certain amount of organic matter is called the biological oxygen demand (BOD). The amount of BOD in the water is an indicator of the level of pollution. If too much organic matter is added to the water all the available oxygen is used up. This causes fish and other forms of oxygen dependent aquatic life to die. Thus anaerobic bacteria (those that do not require oxygen) begin to break down the wastes. Their anaerobic respiration produces chemicals that have a foul odour and an unpleasant taste that is harmful to human health.

3. Inorganic plant nutrients: These are water soluble nitrates and phosphates that cause excessive growth of algae and other aquatic plants. The excessive growth of algae and aquatic plants due to added nutrients is called eutrophication. Excess use of fertilizers is one of the major cause of eutrophication.

4. Water soluble inorganic chemicals which are acids, salts and compounds of toxic metals such as mercury and lead.

5. Organic chemicals 6. Sediment of suspended matter

MARINE POLLUTION Definition: Marine pollution can be defined as the introduction of substances to the marine environment directly or indirectly by man resulting in adverse effects such as hazards to human health, obstruction of


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marine activities and lowering the quality of sea water. While the causes of marine pollution may be similar to that of general water pollution there are some very specific causes that pollute marine waters.

The most obvious inputs of waste is through pipes directly discharging wastes into the sea. Very

often municipal waste and sew-age from residences and hotels in coastal towns are directly

discharged into the sea.

Pesticides and fertilizers from agriculture which are washed off the land by rain, enter water

courses and eventually reach the sea.

Petroleum and oils washed off from the roads normally enter the sewage system but storm

water overflows carry these materials into rivers and eventually into the seas.

Ships carry many toxic substances such as oil, liquefied natural gas, pesticides, industrial

chemicals, etc. in huge quantities some-times to the capacity of 350,000 tonnes. Ship accidents

and accidental spillages at sea therefore can be very damaging to the marine environment.

Shipping channels in estuaries and at the entrances to ports often require frequent dredging to

keep them open. This dredged material that may contain heavy metals and other contaminants

are often dumped out to sea.

Offshore oil exploration and extraction also pollute the seawater to a large extent.

AIR POLLUTION

Air pollution occurs due to the presence of un-desirable solid or gaseous particles in the air in quantities that are harmful to human health and the environment. Air may get polluted by natural causes such as volcanoes, which release ash, dust, sulfur and other gases, or by forest fires that are occasionally naturally caused by lightning.

Pollutants that are emitted directly from identifiable sources are produced both by natural events (for example, dust storms and volcanic eruptions) and human activities (emission from vehicles, industries, etc.). These are called primary pollutants.

There are five primary pollutants that together contribute about 90 percent of the global air pollution. These are carbon oxides (CO and CO2), nitrogen oxides, sulfur oxides, volatile organic compounds (mostly hydrocarbons) and suspended particulate matter.

Pollutants that are produced in the atmosphere when certain chemical reactions take place among the primary pollutants are called secondary pollutants. Eg: sulfuric acid, nitric acid, carbonic acid, etc.

Pollutants Source

Carbon monoxide Incomplete combustion of organic material

Sulfur oxides Sulfur containing fossil fuels are burnt

Nitrogen oxides Vehicular exhausts

Hydrocarbons Evaporates from fuel supplies or remnants of fuel that didn’t burn completely

Particulates Smoke particles from fires, bits of asbestos, dust particles and ash from industries

Lead Emitted by vehicles due to leaded petrol

Particulate matter Particulates are small pieces of solid material dispersed into the atmosphere. The effects of particulates range from soot to the carcinogenic (cancer causing) effects of asbestos, dust particles and ash from


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industrial plants that are dispersed into the atmosphere. Repeated exposure to particulates can cause them to accumulate in the lungs and interfere with the ability of the lungs to exchange gases.

Effects of air pollution on atmosphere:

Ozone layer depletion

Green House effect

NOISE POLLUTION Noise is undesirable and unwanted sound. 125-130 dB is consider as the limit above which any sound is not safe for the auditory system of any Human being. Effects of noise pollution on human health: The most direct harmful effect of excessive noise is physical damage to the ear and the temporary or permanent hearing loss often called a temporary threshold shift (TTS). People suffering from this condition are unable to detect weak sounds. However hearing ability is usually recovered within a month of exposure. Permanent loss, usually called noise induced permanent threshold shift (NIPTS) represents a loss of hearing ability from which there is no recovery. Below a sound level of 80 dB haring loss does not occur at all. However temporary effects are noticed at sound levels between 80 and 130 dB. About 50 percent of


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the people exposed to 95 dB sound levels at work will develop NIPTS and most people exposed to more than 105 dB will experience permanent hearing loss to some degree. A sound level of 150 dB or more can physically rupture the human eardrum. Noise can also cause emotional or psychological effects such as irritability, anxiety and stress. Lack of concentration and mental fatigue are significant health effects of noise.

THERMAL POLLUTION The discharge of warm water into a river is usually called a thermal pollution. It occurs when an industry removes water from a source, uses the water for cooling purposes and then returns the heated water to its source.

SOLID WASTE MANAGEMENT of URBAN AND INDUSTRIAL WASTE: Control measures of urban and industrial wastes: An integrated waste management strategy includes three main components:

1. Source reduction 2. Recycling 3. Disposal: Disposal of solid waste is done most commonly through a sanitary landfill or through

incineration.

Multilateral treaties to curb pollution Rotterdam convention: The Rotterdam Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade, more commonly known simply as the Rotterdam Convention, is a multilateral treaty to promote shared responsibilities in relation to importation of hazardous chemicals. The


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convention promotes open exchange of information and calls on exporters of hazardous chemicals to use proper labeling, include directions on safe handling, and inform purchasers of any known restrictions or bans. Signatory nations can decide whether to allow or ban the importation of chemicals listed in the treaty, and exporting countries are obliged make sure that producers within their jurisdiction comply. Stockholm convention on Persistent Organic Pollutants (POP): It is an international environmental treaty, signed in 2001 and effective from May 2004, that aims to eliminate or restrict the production and use of persistent organic pollutants (POPs). Endosulfan was recently banned by it. Basel convention: The Basel Convention on the Control of Trans-boundary Movements of Hazardous Wastes and Their Disposal, usually known as the Basel Convention, is an international treaty that was designed to reduce the movements of hazardous waste between nations, and specifically to prevent transfer of hazardous waste from developed to less developed countries (LDCs). It does not, however, address the movement of radioactive waste. The Convention is also intended to minimize the amount and toxicity of wastes generated, to ensure their environmentally sound management as closely as possible to the source of generation, and to assist LDCs in environmentally sound management of the hazardous and other wastes they generate.

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