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|Referát vhodný pre:||Stredná odborná škola||Počet A4:||2.5|
|Priemerná známka:||3.00||Rýchle čítanie:||4m 10s|
|Pomalé čítanie:||6m 15s|
Tropical rainforests provide a natural defense against hurricanes, cyclones, and typhoons. However, as rainforests are cut down, tropical storms kill at least 20,000 people each year and cause $4 bilion in damage. Flooding and soil and water degradation caused by tropical deforestation periodically disrupts the lives of approximately 1 billion people.
On the Air:
Due to the deforestation of dense, virgin rainforests, 1,4 billion tons of carbon dioxide enter the Earth’s atmosphere each year. Ten percent of it derives from the destruction of Brazilian rainforest. Burning rainforests are the source forr about 20% of carbon dioxide released each year.In single day, satellite photos have show 7,603 different fires raging in the Brazilian rainforests! The smell of smoke is not unusual in the rainforests. Because of heavy smoke in the air, local airports are sometimes closed. In 1997, the smoke from forest fires burning out of control was cause of a plane crash in Indonesia.
On the Land:
A primary or virfgin rainforest is one that reaches a state of balance and adulthood. A secondary forest is a primary forest, that has been cut down and then replanted. However the secondary forest harbors only ¼ of the plant and animal species of the original and the lifespan of the trees decreases. It takes nearly 1,000 years for a secondary forest to evolve byck into primary forest. Just 3 years after deforastation, the land loses half its organic content.
4)Reasons to save the rainforests:
The rainforests contains such a plethora of life that humans have been unable to classify and name all of it. Brazil has ane-third of the world’s remaining rainforests. Yet humans identified only 10% of the plant species that occupy them. Tropical rainforests provide between 25 to 50% of all pharmaceutical products. Three thousand plants have anti-cancer properties. Of these, 70% inhabit the rainforests. Only 1% of tropical plants have examined for possible medicinal use. But, those that have field ¼ of all prescription drugs sold in the United States.
Governments in rainforest countries need to plan and work together. they should also protect certain areas and plant new forests….