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世界的森林面积,相当于陆地面积的约30%,有33亿公顷。其中约40%是非经济林。发达地区(北美、苏联、欧洲、大洋洲)与发展中地区(中南美、亚洲、非洲)的森林面积差别甚大,前者约有17亿公顷(占总数的44%),后者21亿公顷(占总数的56%)。从经济林占森林面积的比例来看,发达地区为76%,发展中地区46%。森林面积多的国家有苏联、加拿大、芬兰、美国等。这些国家共占世界森林面积的一半以上。全部森林面积的约
The world’s forest area, equivalent to about 30% of land area, 3.3 billion hectares. About 40% of them are non-economic forests. The forest area in the developed regions (North America, USSR, Europe, Oceania) and developing regions (Central and South America, Asia and Africa) varies widely, with the former accounting for about 1.7 billion hectares (44% of the total) and the latter 2.1 billion hectares 56% of the total). From the ratio of economic forest to forest area, the developed areas are 76% and the developing regions 46%. Countries with large forest area are the Soviet Union, Canada, Finland, the United States and so on. Together, these countries make up more than half of the world’s forest area. Approximate total forest area