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2010-04-13T18:36:19+02:00
Or deforestation threatens the environment?
Destroying the environment is the greatest threat to plants and animals around the world. In some cases, such as logging in tropical forests. shall be destroyed, often with the impression that it was for the good of mankind, acquired land will be cultivated. The tragedy brings the lack of understanding of the linkages between environment and life cycle of certain species. An example of mangrove swamp drainage, ripening of many fish species. Sometimes the wetland habitat is treated as a disease spread and insects, and dried them without taking into account the damage they cause to other species. Forests are cut because of the harvested wood, forgetting that they are biological systems maintaining proper water balance, without which in times of rain the river will flow faster, causing soil erosion at upper reaches, and depositing sediment at the mouth of the sea.
Although the experience should show that the destruction of the environment is often far-reaching effects, not to predict in the early stages of new developments, the human race in many cases seems to be unable to draw valid conclusions. Politics and immediate profits seem to have prevailed over rozsądnym thinking and the use of the riches of nature, which connects to minimize interference with the environment.
Once the vast expanses of forest stretched around the world. Coniferous forests of Asian and North American taiga passed in the tundra in the north and south have changed in the deciduous forests. Near the equator were dense tropical forests. But with the spread of man, this picture has changed.
In the lowland areas of temperate zones, such as most of Europe, forest cover losses entailed disastrous consequences, although the number of species declined. But if logging was carried out in the mountains, like the top layer of soil is often not related obsuwała the steep slopes. In high rainfall areas of rain, as in Scotland, that will create wet deserts, where they can survive only a few species. In Europe and America, Euro, more previously stripped areas shall be re-afforested. This restores the tree, but does not restore the whole of biological diversity, particularly of animals. At the same time taiga in the north of Asia is being destroyed on a large scale.
However, most tropical forests are threatened. Today they occupy about 6% of the Earth, but it is almost half of all existing forests and it is believed that 70-90% of them living out of living species, many of which are still unknown and has great potential value for humans, eg in medical whether the economy. Traditionally, small patches of forests were hewn, or burned for agriculture, purified, and grown for several years and then return to the jungle.
Farmland occupy a seat of various forest monoculture or mixed, and the majority of animals killed along with the trees. In South America, the former forest land grazed by cattle, but because the forest soils are very fertile, cattle devastating the environment.
Searching for gold and other minerals has caused serious pollution of rivers, and demand for wood is so great that the forests are cut on a large scale in some areas to poachers drzewni get even in areas of reserves.
Global wood consumption is about 3, 4 million cubic meters per year. About half of that is used as fuel in industry.