Class 12 Revision Notes Economics Environment and Sustainable Development
Environment is defined as the total planetary inheritance and the totality of all resources. It includes all the biotic and abiotic elements that influence each other.
All living elements-the birds, animals and plants, forests, fisheries etc. are biotic elements.
Abiotic elements of the environment includes non-living elements like air, water, land, rocks and sunlight etc.
Functions of the Environment
(i) Environment supplies resource (both renewable and nonrenewable resources) for production.
(ii) Environment assimilates waste,
(iii) Environment sustains life.
(iv) Environment enhances quality of life.
The environment is able to perform these functions without any interruption as long as demand on these functions are within its carrying capacity.
Carrying capacity implies two things:
(i) Resource extraction should remain below the rate of resource regeneration.
(ii) Generation of wastes should remain within the absorption capacity of the environment.
If these two conditions are not fulfilled, then environmental crisis occurs.
Absorptive capacity of the environment means the ability of the environment to absorb degradation.
The various reasons for environmental crisis are as under:
(i) Population explosion and advent of industrial revolution.
(ii) The intensive and extensive extraction of both renewable and nonrenewable resources.
(iii) The affluent consumption and production standards of developed countries.
Renewable resources are those which can be used without the possibility of the resource becoming depleted or exhausted. That is, a continuous supply of resource remains available for e.g. tress in forest and the fish in the oceans.
Non renewable resources are those which get exhausted with extraction and use. For example, fossil fuel.
(i) Problem of pollution.
(ii) Problem of excessive exploitation of natural resources.
Pollution is contamination of useful things such as air, water, land etc. with undesirable or harmful materials like foul gases, smoke, poisonous chemicals, etc.
The major forms of pollution are as follow
(i) Air pollution
(ii) Water Pollution
(iii) Noise Pollution
(iv) Land Pollution
Global warming is a gradual increase in the average temperature of the earth’s lower atmosphere.
Global warming is caused by man-made increase in carbon dioxide (Co2) and other greenhouse gases through the burning of fossil fuels and deforestation.
Some of the long term results of global warming are as follow:
(i) Melting of polar ice with a resulting rise in sea level and coastal flooding.
(ii) Extinction of species as ecological niches disappear.
(iii) more frequent tropical storms and
(iv) An increased incidence of tropical diseases.
Ozone depletion refers to reduction in the amount of Ozone (a protective layer) in the stratosphere.
The problem of Ozone depletion is caused by high levels of CFC used as cooling substances in air conditioners and refrigerators or as aerosol propellants and bromofluro-carbons used in fire extinguishers.
As a result of depletion of the ozone layer, more ultra violet (UV) radiation comes to earth causing damage to living organism.
The threat to India’s environment poses a dichotomy-threat of poverty-induced environmental degradation and, at the same time, threat of pollution from affluence and rapidly growing industrial sector.
Air pollution, water contamination, soil erosion, deforestation and wildlife extinction is some of the most pressing environmental concerns of India.
The priority issues identified in India are:
(i) Land degradation
(ii) Biodiversity loss
(iii) Air pollution with special reference to vehicular pollution in urban cities.
(iv) Management of fresh water.
(v) Solid waste management.
Land degradation refers to a decline in the overall quality of soil, water or vegetation condition, commonly caused by human activities.
Some of the factors responsible for land degradation is
(i) loss of vegetation occurring due to deforestation.
(ii) Forest fires and over grazing.
(iii) Improper crop rotation.
(iv) Encroachment into forest lands.
(v) Shifting cultivation.
(vi) Indiscriminate use of agrochemical such as fertilizers and pesticides.
(vii) Improper planning and management of irrigation systems.
(viii) Extraction of ground water in excess of the recharge capacity.
(ix) Poverty of the agriculture-dependent people.
(x) Non-adoption of adequate soil conservation measures.
Chipko and Appiko movements are related to protect forests.
In order to address two major environmental concerns in India, viz, water and air pollution, the government set up the central pollution control board (CPCB) in 1974. Board investigate, collect and disseminate information relating to water, air and pollution, lay down standards of sewage/trade effluent and emissions.
Functions of the Central Board at the National Level
- Advise the Central Government on any matter concerning prevention and control of water and air pollution and improvement of the quality of air.
- Plan and cause to be executed a nation-wide programme for the prevention, control or abatement of water and air pollution;
- Co-ordinate the activities of the State Board and resolve disputes among them;
- Provide technical assistance and guidance to the State Boards, carry out and sponsor investigation and research relating to problems of water and air pollution, and for their prevention, control or abatement;
- Plan and organise training of persons engaged in programme on the prevention, control or abatement of water and air pollution;
- Organise through mass media, a comprehensive mass awareness programme on the prevention, control or abatement of water and air pollution;
- Collect, compile and publish technical and statistical data relating to water and air pollution and the measures devised for their effective prevention, control or abatement;
- Prepare manuals, codes and guidelines relating to treatment and disposal of sewage and trade effluents as well as for stack gas cleaning devices, stacks and ducts;
- Disseminate information in respect of matters relating to water and air pollution and their prevention and control;
- Lay down, modify or annul, in consultation with the State Governments concerned, the standards for stream or well, and lay down standards for the quality of air; and
- Perform such other function as may be prescribed by the Government of India.
India’s rapid economic development has made us aware of two realities:
(i) Economic development has lifted millions out from poverty.
(ii) Economic development has been accompanied by accelerated depletion of natural resources and rapid deterioration in environment quality.
Sustainable development is that process of development which meets the needs of present generation without reducing the ability of future generation to meet their own needs.
Main features of sustainable development is as under:
(i) Sustained rise in Real per Capita Income and Economic welfare.
(ii) Rational use of natural resources.
(iii) No reduction in the ability of the future generation to meet their own needs.
(iv) Check on pollution.
To achieve sustainable development, the following needs to be done:
(i) Limiting the human population.
(ii) Technological progress should be input efficient and not input consuming.
(iii) Renewable resources should be extracted on a sustainable basis, that is, the rate of
extraction should not exceed rate of regeneration.
(iv) For non-renewable resources, rate of depletion should not exceed the rate of creation of renewable substitutes.
(v) Inefficiencies arising from pollution should be corrected.
Strategies for Sustainable Development.
(i) Use of non-conventional sources of energy.
(ii) Use of cleaner fuels: LPG, Gobargas in rural areas and CNG in Urban areas.
(iii) Use of Solar energy and wind power.
(iv) Shift to organic farming.
(v) Recycle the wastes
(vi) Public means of transport.
(vii) Traditional knowledge and practices.
(viii) Establishment of Mini-Hydel plants.
(ix) Biopest Control
Revision Notes for Class 12 – Free PDF Download
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