Публикация на английском языке на тему BIODIVERSITY IN DANDER для студентов колледжа

BIODIVERSITY IN DANDER

All organisms on Earth are dependent on each other in some way ,including humans .The interplay between biotic and abiotic factors makes possible the diversity of organisms that exists today .

Natural ecosystems have a vast genetic library ,yet researchers have strong evidence that ecosystems are in the opening stages of an extinction episode .There is a sudden and pronounced decline in the worldwide abundance and diversity of ecologically different groups of organisms ,particularly those from tropical rain forests .Such a rate extinction is the most extreme in the past 65 million years .Some researchers estimate that at the current rate ,more than one million species may become extinct by the end of this century.

The primary cause of this decay in diversity is not direct human exploitation but the indirect habitat destruction that result from the expansion of populations and activities .As the human population grows ,it places greater demands on the ecosystem for space and goods .As a result ,land is cleared for cultivation and living space ,destroying the habitat of many organisms .

Organisms require appropriate habitats if they are to survive .Just as people cannot live in atmosphere with too little oxygen ,trout cannot breed in water that is too warm or too acidic .Red-eyed vireos ,scarlet tanagers ,and other birds must have mature tropical forests in which to spend the winters .Black -footed ferrets require prairie that still supports prairie that still supports prairie dogs ,their major source a food .

Through other organisms have provided humans with crops ,domesticated animals ,a variety of industrial products ,and many important medicines,the roles that microorganisms,plants,and animals play within the natural ecosystem are the most important. All these organisms exchange gases with their environments and are thus involved in maintaining the mix of gases in the atmosphere . Changes in that mix ,such of increases in carbon dioxide ,nitrogen oxides , and methane , can lead to rapid climatic change and ,in turn ,agricultural disaster .Destroying forests leads to timber shortages ,water shortages ,and increased danger of flooding .Destruction of some insects can lead to the failure of crops that depend on insect pollination .Extermination of the enemies of insect pests can lead to severe pest outbreaks. These extermination of soil organisms can destroy the fertility of the soil.

Researchers are attempting currently to determine the extent to which humans have devastated the diversity of organisms of the effect these changes will have on the ecosystems of the world . Solutions to these problem are even more difficult to determine . Some solutions require a massive change in human life-style .Others involve the use of new genetic techniques to perpetuate diversity , such as embryo transplants between an endangered species and a domestic species . Whether or not some of these solutions work is yet to be seen .