Исправьте ! problem of contamination of water(seas, rivers, lakes etc.) - one of most actual. man irretrievably changes the natural mode of water objects the activity by wastes and upcasts. there is much water on earth, fresh water - all 3%, other 97% is water of seas and oceans. three fourths of fresh water the living organisms are not accessible to, because it is water of glaciers. glacial water is a supply of fresh water.almost all mass of water is concentrated in oceans. evaporating from the surface of oceans water gives moisture all ecosystems of dry spell. dry land returns water to the ocean. on an exchange moisture between dry land and ocean is expend plenty of energy : on it 1/3 energies that acts sun on earth are spent.before development of human civilization a cycle of water on a planet was equilibrium. an ocean from the rivers got such amount of water, expended that at her evaporation. at an unchanging climate the rivers did not grow shallow, a water level did not have gone down in lakes. with development of human civilization this cycle was violated. contamination of oceans

Many centuries ago people lived in harmony with nature because industry was not much developed. There was no ecological problem until people built lots of plants and factories which sent wastes into the air, water and land where they didn't disappear but lasted forever in one form or another. Nowadays people live only according to their wants and requirements, they ignore the laws of nature. That's why today the contradictions between man and nature are dramatic. People are slowly destroying the nature environment around them. Today we are anxious about the state of the air we breathe because every year world industry throws out into atmosphere about 1 000 million tons of dust, smoke and other harmful substances and people of many cities suffer from smog. Another reason why there is such high level of air pollution in large cities is because of car exhaust fumes from very intensive transport. A great number of plants get used to dump poisonous chemical wastes in rivers, lakes and seas that has led to polluting water and killing fish life. At present time pollution from sinking ships and tankers with oil is increasing and there is a strong destruction of sea life. We face the fresh water supply problem today because of the depletion of water resources and the disruption of water cycle. Speaking about atmosphere we should mention ozone holes which are result of air pollution and their increase can lead to the destruction of the whole great chain of life of our planet. The pollution of the air, oceans, seas, rivers and lakes and the destruction of the ozone layer could lead our planet to a global catastrophe. But the most terrible catastrophe of our age is the Chernobyl disaster which has resulted not only in atomic explosion but has brought death to 300 thousands hectares of farm lands and has affected the lives of millions of people. The radiation doses have affected and will continue to affect the health of people living in contaminated areas. The Earth is our home that's why we must take measures to fight land pollution and keep our environment clean; we must plant trees and flowers and take care of animals, we must not throw our wastes into the rivers. In many countries environmental protection organizations such as "Green Peace", "Friend of the Earth", "World Wild Life Fund" are set up which try to put pressure upon the governments that don't care for ecology in their countries. The humankind will be able to survive only if we all realize that environmental protection is our universal concern.