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SOCIAL ROOTS OF ECOLOGICAL PROBLEMS .
The ecological problem, which is also very much a social one, is one of the pressing problemsof our days. It is closely linked through cause-and-effect relations to the problems of economic growth, progress in science and technology, natural resources, energy and food supplies. In many cases the environmental problem has become a dominant one in relation to many others.
The pollution of the environment, the destruction of ecosystems, the destruction of many species of plants and animals has now reached threatening proportions. An increasing influence on nature and the application of new technological processes (whose consequences are increasingly dangerous for the environment) may cause catastrophic results. Negative anthropogenic influences threaten to disrupt nature's basic cycles and to undermine the self-regenerating capacitiesof the biosphere and of its individual components.
This is illustrated by the following data. By comparison with the beginning of the twentieth century the accumulation of carbon dioxide in the atmosphere, as well as of aerosols, has increased dozens of timesin many cities, and has increased globally by 20 per cent. As a result of the formation of a layer of carbon dioxide around the Earth which encloses it like a glass cover the threat of unfavourable changes in climate has arisen that may transform our blue planet into an enormous greenhouse during the next decades, with possibly catastrophic effects. Those include changes in its energy balance and a gradual increase in temperature that will transform fertile region into arid ones, raise the level of water in the oceans (through the melting of polar and drifting ice) and produce a flooding of great numbers of coastal lands and cities. The threat of a disruption in the oxygen balancehas arisen through the destruction of the ozone screen in the lower stratosphere as a result of the flights of supersonic aircraft (its destruction by 50 per cent can increase ultraviolet radiation 10 times, with corresponding influences on the sight of animals and humans). Pollution of the ocean has increased at a rate that threatens to make it global (4.106 tons of petroleum are channeled to the ocean, i.e., approximately 0.1 per cent of petroleum production on maritime shelves).
All this exerts a substantial adverse influence on the health of individuals, their labour productivity, and their creative activities and requires increasing capital investments in order to sustain the fertility of agricultural lands and purify water bodies, since their waters are becoming unsuitable both for general use and for use in the economy
The pollution of the environment through chemical, physical and biological agents (the development of micro-organisms and agricultural pests that are urn drugs and poisons) together with increases in the volume and types of ionizing radiation, produce, among other things, an increase in their mutagenic influence, on individuals, that is, in pathological changes in heredity, and a greater number of hereditary defects, diseases, genetically determined forms of vulnerability to serious and chronic diseases. These impede the vital activities and reproductive functions of individuals and cause their genetic degeneration.
Calculations of researchers indicate that increases in natural background radiation by only 10 rads may lead to the birth of 6 million hereditarily defective persons in each generation. Already now, according to UN experts, 10.5 per cent of people are born with hereditary (genetic) defects. Data concerning deaths from cancer published by the National Cancer Institute of the U.S. indicate that 60 per cent or more of the cases (500,000 cases of cancer per year) are caused by various cancer-producing factors in the environment.
1. Read the following passages of the text and extract the main idea of the each one. Use the expressions like “On the one hand…. but on the other…” or “For one thing … for another one…”.
Model: On the one handthe construction ofhigh-rise buildings economizes city land but on the otherit has led to extremely high density of population.
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