| 世界热带林现状及发展战略(上) |
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| 引用本文： | 关百钧,李维长.世界热带林现状及发展战略(上)[J].世界林业研究,1989,2(4):16-24. |
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| 作者姓名： | 关百钧 李维长 |
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| 作者单位： | 中国林科院情报所 |
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| 摘 要： | 森林资源的消长与社会经济发展密切相关,而林业的兴衰又直接关系到国民经济和社会的发展。当前,世界林业面临的"四大危机"大部分又是与热带林的破坏密切相关的。因此,研究热带林发展战略是研究当前世界林业的核心问题。本文根据国际组织和各国的大量文献,着重就世界热带林的现状、毁林速度、毁林模式、原因和后果等问题进行了论述。
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| 关 键 词： | 热带林-毁林 森林资源-资源动态 森林生态-生态平衡 沙漠化 |
| 收稿时间： | 9/4/1989 12:00:00 AM |
Present Situation and Development Strategy of Global Tropical Forests |
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| Guan Baijun and Li Weichang.Present Situation and Development Strategy of Global Tropical Forests[J].World Forestry Research,1989,2(4):16-24. |
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| Authors: | Guan Baijun and Li Weichang |
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| Institution: | Information Research Institute, Chines Academy of Forestry |
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| Abstract: | Tropical forests are one of. the earth's most ancient ecological systems and most valuable natural resources as well. The FAO/UNEP Tropical Forest Resources Assessment project concluded that in 1980, the total of 1935 million hectares of tropical forests represents 44.8 percent of the global forest areas, with the total volume of standing timber being 181.3 billion m3. However, the serious destruction of tropical forests has been a terrific problem and being paid close attention by international societies in recent years. For the period 1981-1985, 11.3 million hectares of tropical forests were cleared every year, of which tropical America deforested 5.61 million (49.6%) annually and tropical Africa and tropical Asia lost forests of 3.68 million and 2.01 million separately. The direct causes leading deforestation include mainly: (1) Shifting cultivation. The destroyed tropical forests by shifting cultivation covered almost half of the total areas of deforestation in global tropics in 1981-1985; (2) Over-firewood gethering. Firewood-deficient populations will increase from 1 600 million in 1980 to 2700 million in 2000 and deficient firewood will amount to 900 million m3 annually; (3) Over-pasture. The number of livestock in many countries has exceeded the capacity of herding on the existing grazing-land which results in enlarging grasslands in forests; (4) Illegal felling and robberlike cutting, that is felling valuble species regardless of destruction of other species around, and some developed countries seeking after timber resources from developing countries for the purpose of preserving thier own forest resources which also bring about robberlike cutting. (5) Forest fire. 0.2 million forest fires occur in the world annually and the areas destroyed cover more than 15 million hectares; (6) Unfit national policies and development projects, such as transmigration programmes, dams and reservoirs construction, road constructions etc, some of these projects were subsidized by international aid agencies. The serious destruction of tropical forests has created grave endangerment on global ecosystem resulting in critical consequences:disorder of nutrient cycle, loss of soil fertility, decrease in animal and plant species, soil erosion, flood and drought, desertification and climate change. |
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