Ecology is the study that helps to preserve the Earth, its plants and animals.at present times we have to face such ecological problems as acid rain, global warming, loss of rare species, ozone reduction, etc. Many scientists think that it is connected with industrial boom and development of civilization in the world. Another problem which is worth mentioning is the tree cutting. Trees are a source of oxygen and clean air. So, by doing this people simply violate the biological balance. All the above mentioned ecological problems are the result of man's careless interaction with nature.