The environment means surroundings in which people, animals and plants develop and exist. The branch of biology investigating relationships between living beings and their environment is called ecology. It is a relatively new science which reflects the concern about the balance of nature. Ecologists and environmentalists are very well aware of the bad sate of environment and of the necessity of its protection. The most serious ekological problems of today are the pollution of air, water and soil, the destruction of ecosystems, disappearance of many species of animals and plants, the weather changes, acid rains, the warming up of the Earth´s surface, the destruction of tropical forests and the breaking of the ozone layer. Most of this damage, which proceeds faster and faster, has not been caused by natural catastrophies, such as earthquake, floods or tornadoes but by the man himself. The technical progress, which enables him a more comfortable life, leads on the other hand to the degradation of the quality of the environment, which he lives in.
The growing number of cars on roads and highways contribute much to the air pollution. Factories produce large quantities of carbone dioxide, lead poisons, radioactive particles, dangerous compounds of sulphur and nitrogen, which get into the air. Some of them in combination with water make sulphuric acid in the clouds. These dangerous clouds are then blow by the winds and later fall acid rain. Acid rains kill trees, then they get into the soil and make it infertile. The polluted rain water is carried to the rivers and all life disappears from them. Factories directly increase water pollution because many of them are built near rivers into which they put their chemical waste.
Farmers use amounts of pesticides to kill certain insects that can be killed by other less dangerous means. They also use fertilizers which pollute the soil and most of them may have the worst effects on human health, too. The bulding of dams causes flooding of large areas of nature and the disappearance of many typical animals, birds and plants of the region. Amounts of industrial and city waste are placed near the lakes and rivers. They pollute the soil, water and air, and spoil the natural scenery.
If the destruction of the environment continues the life on this planet will be endangered. People, animals, birds and plants can´t exist without air, water and soil.