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1 热带林的现状 热带林是可再生的自然资源,但其急剧地减少和退化,将会给地球环境造成重大影响。地球上现存的森林面积大约45亿公顷,其中43％分布在最冷月18℃以上的热带地区。热带林随旱季、雨季的长短变化可分为热带雨林、热带季节林、热带高草原、热带半沙漠等,还可根据树林疏密分为热带封闭林和热带稀疏林。热带雨林约占11亿公顷。从面积规模来看,热带雨林
1 STATUS OF A TROPICAL FOREST Tropical forest is a renewable natural resource, but its drastic reduction and degradation will have a significant impact on the Earth’s environment. About 4.5 billion hectares of forest exist on Earth, 43% of which are found in tropical regions above 18 ℃ in the coldest month. Tropical forest with the dry season, the length of the rainy season can be divided into tropical rain forest, tropical seasonal forest, tropical high grassland, tropical semi-desert, but also according to the density of the forest is divided into tropical and coniferous forest tropical forest. Tropical rain forest accounts for about 1.1 billion hectares. From the size of the area, the tropical rain forest