The environmental problems that have threatened the survival of mankind so far and have been recognized by mankind are: global warming, destruction of the ozone layer, acid rain, the crisis of fresh water resources, energy shortages, the sharp decline of forest resources, land desertification, accelerated extinction of species, garbage, toxic chemical pollution and many other aspects.
Environmental problems are diverse, summarized in two categories: one is the natural evolution and natural disasters caused by the primary environmental problems, also known as the first environmental problems. Such as earthquakes, floods, droughts, typhoons, collapses, landslides, mudslides and so on. One category is secondary environmental problems caused by human activities, also called second environmental problems. Secondary environmental problems are generally subdivided into two categories: environmental pollution and ecological damage.
For example, the destruction of forest vegetation caused by indiscriminate logging, the degradation of grassland caused by overgrazing, the desertification and land sands caused by extensive reclamation of grassland, and the deterioration of the atmosphere and water environment caused by industrial production.
Extended information:
p>The cause of land pollution: the cleanup of garbage has become an important issue in major cities, and of the millions of tons of garbage every day, so much of it can't be incinerated or putrefied, such as plastics, rubber, glass, and other enemies of mankind's number one.
Marine pollution causes: mainly from oil tankers and oil wells leak out of the crude oil, pesticides and fertilizers used in agricultural fields, sewage discharged from factories, acidic solutions from mines; they make most of the ocean lakes are polluted, the result is not only the victims of the marine organisms, that is, the birds and human beings may be poisoned because of these organisms and enter the biological chain.
Causes of air pollution: This is the most direct and serious, mainly from factories, automobiles, power plants and so on, emitting carbon monoxide and hydrogen sulfide, etc., and every day people are exposed to these dirty air and contracted respiratory or visual organ diseases. If we continue to ignore the warnings of the experts, we will certainly end up with no clean land to live in.
Baidu Encyclopedia - Environmental Issues