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Anthropogenic effects on the environment


 

Air Pollution

 

Air pollution is the result of man’s use of lethal chemicals. Air pollution in industrialized countries caused a visible haze called smog. Smog is a mixture of different pollutants (mainly sulphur dioxide gas and particles of soot) and water vapor in still, cold air. A lot of dangerous gases enter the atmosphere from tall chimneys of factories and power stations. These gases react with water droplets, forming a diluted mixture of sulphuric acid and nitric acid. Then this mixture returns to the Earth in the form of acid rain.

The effects of acid rain are most clearly lakes, streams, rivers, oceans and other bodies of water. Acid rain directly falls on water, but it can flow into rivers after it falls on land. Lakes and streams become acidic when the water and the land around it cannot neutralize the acid rain. Animals that live in the water environment are hurt and possibly killed. Some fish can tolerate only а certain amount of acid before dying. For example, in Sweden at least 40,000 of the 90,000 lakes have been affected, and in the USA one in five lakes suffers from this type of pollution.

 

Soil Pollution

 

Contamination with pesticides has seriously affected the biosphere in many areas; the humus content оf the soil is decreasing and the activity of soil organisms is declining. Soil structure is breaking down owing to excessive ploughing and artificial fertilizer use. Toxic metals such as lead, mercury, copper, cadmium, zinc and aluminum from industrial wastes, find their way into the food chain via plants grown on contaminated land.

The pollution emitted by industry and the communal economy in urbanized areas is causing the contamination of soils and crops with heavy metals, particularly around non-ferrous metal plants. This in turn is affecting food production.

Solid waste from the power generation industry is increasing, as more dust is collected from smokestacks and as more coal is calcined.

The mechanical damage to the topsoil occasioned by the winning of low-grade energy and minerals is compounded by the accelerating production of spoils, washings, fly ash and calcined coal which have to be stored or dumped, rendering more topsoil usе1ess or inaccessible.

 

The Biodiversity Problem

 

Humans have extensively changed the world’s ecosystems. The plants, animals and micro-organisms around us are under threat. The reasons include poor planning, wasteful land use, over-fishing and intensive farming, which bring with it high levels of pesticide use.

We need birds for our survival, for example, because they are a vital link in natural ecosystems such as forests, wetlands and the marine environment. Yet nearly half Europe’s bird species are threatened by extinction or serious decline. A study of 23 common farmlands birds and 24 common woodland birds in 18 European countries has shown that numbers declined by 71% between 1980 and 2002. Birds are recognized as a good indicator of the general state of biodiversity, so their decline is an alarm signal.

So, the group of students of our institute has learned the biodiversity problem on the territory of Muromsky game reserve. Caring for our landscapes and wildlife is the main task of our ecological group. The aim of our investigations is estimating the ecological landscape state on the territory of the game reserve, making up landscape types characteristics, defining degrees of anthropogenic effects.

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