Chapter 7 — Environment and Sustainable Development

Chapter 7 is titled 'Environment and Sustainable Development.' It covers the definition and functions of the environment, the state of India's environment including major concerns like land degradation and air pollution, and strategies to achieve sustainable development that safeguards resources for future generations.

According to the chapter, environment is defined as the total planetary inheritance and the totality of all resources. It includes all biotic factors — birds, animals, plants, forests, fisheries — and abiotic factors such as air, water, land, rocks, and sunlight, which all influence each other.

The environment performs four vital functions: (i) it supplies resources, both renewable (trees, fish) and non-renewable (fossil fuels); (ii) it assimilates waste; (iii) it sustains life by providing genetic and biodiversity; and (iv) it provides aesthetic services like scenery.

Renewable resources can be used without the possibility of becoming depleted or exhausted — a continuous supply remains available; examples are trees in forests and fish in the ocean. Non-renewable resources get exhausted with extraction and use; fossil fuel is given as an example.

Carrying capacity means that resource extraction must not exceed the rate of regeneration of the resource, and the wastes generated must remain within the assimilating capacity of the environment. The chapter compares carrying capacity to the 'plimsoll line' of a ship — the load limit mark — beyond which the ship (or economy) becomes unsafe.

The five priority environmental concerns identified for 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, and (v) solid waste management. The chapter also notes that 70 per cent of water in India is polluted.

The United Nations Conference on Environment and Development (UNCED) defined sustainable development as: 'Development that meets the need of the present generation without compromising the ability of the future generation to meet their own needs.' This definition stresses the concepts of 'needs' and 'future generations.'

Edward Barbier defined sustainable development as one which is directly concerned with increasing the material standard of living of the poor at the grass root level — measurable in terms of increased income, educational services, health care, sanitation, and water supply. It aims at decreasing absolute poverty by providing lasting and secure livelihoods that minimise resource depletion and environmental degradation.

Herman Daly listed five conditions: (i) limit human population to within the environment's carrying capacity; (ii) technological progress should be input-efficient, not input-consuming; (iii) renewable resources should be extracted no faster than their rate of regeneration; (iv) for non-renewable resources, the rate of depletion should not exceed the rate of creation of renewable substitutes; and (v) inefficiencies from pollution must be corrected.

The chapter discusses: use of CNG in urban areas (reducing air pollution in Delhi), LPG and gobar gas plants in rural areas, wind power, solar power through photovoltaic cells (with India leading the International Solar Alliance), mini-hydel plants in mountainous regions, biocomposting using earthworms, biopest control using neem-based pesticides, and reviving traditional knowledge practices such as Ayurveda and mixed cropping.

Global warming is a gradual increase in the average temperature of the earth's lower atmosphere due to increased greenhouse gases since the Industrial Revolution, caused by burning fossil fuels and deforestation. Atmospheric CO2 and CH4 increased by 31 per cent and 149 per cent respectively above pre-industrial levels since 1750. A UN Conference on Climate Change held in Kyoto, Japan, in 1997 resulted in an international agreement calling for reductions in greenhouse gas emissions by industrialised nations.

Ozone depletion refers to reductions in ozone in the stratosphere caused by chlorine and bromine compounds from chlorofluorocarbons (CFCs) used in air-conditioners and refrigerators. A reduction of approximately 5 per cent in the ozone layer was detected from 1979 to 1990. This led to the adoption of the Montreal Protocol, banning the use of CFC compounds and other ozone-depleting chemicals such as carbon tetrachloride and halons.

Appiko (meaning 'to hug') was a forest-protection movement in Karnataka similar to the Chipko movement in the Himalayas. On 8 September 1983, when tree-felling began in Salkani forest in Sirsi district, 160 men, women, and children hugged the trees and forced the woodcutters to leave. They kept vigil for six weeks, ultimately saving 12,000 trees, and the movement spread to many adjoining districts.

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