Since humans populated the earth, they have caused a devastating effect on the natural environment. In the past, the earth's air has been polluted, many forests have been destroyed and thousands of animals have become extinct.
Air pollution has become a major problem since the first machines were made. Each year industrial developed countries generate billions of tones of pollutants. The major pollutants are: carbon monoxide, sulfur dioxide, nitrogen dioxide, ozone, lead, particles and volatile organic compounds. However most of the air pollution comes from the burning of fossil fuels.
Petroleum is a commonly burnt fossil fuel as it is used in cars, which are many countries greatest atmospheric pollutant. Industrial activities, the burning of fossil fuels and vehicle numbers are still increasing. Action must be taken to insure a future of a clean atmospheric environment.
Forests are very important natural resources. They supply us with oxygen, food, timber, medicine and homes for animals.
Unfortunately, they are gradually decreasing due to the needs of timber, fuels and farmland. In some countries logging has become so bad that less than 50% of the original forests are left. As a result of this there have been many arguments between green groups and loggers. Although the green groups fight very hard the loggers normally win and end up destroying more forests.
The spread of human population has caused the extinction of many animals. Although the extinction of animals is a natural part of evolution, the number of species that have become extinct has increased dramatically since the 1600's. The main causes of this are: the destruction of animal habitats, to make way for new roads or buildings, an upset in the ecosystem, diseases, and for human sports, such as hunting. All of the world creatures play a role in the circle of...