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世界热带人工造林及其存在的问题联合国粮农组织１９９３年发表的一个报告指出，世界热带９０个国家到１９９０年为止，已累计人工造林４３８０万ｈｍ２，亚太热带１７国占其中的７３％，拉美和加勒比热带３３国占２０％，非洲热带４０国占７％。热带造林成活保存率估计为...
World Tropical Artificial Afforestation and Its Problems In a report released by the UN Food and Agriculture Organization in 1993, 90 countries in the world’s tropical oceans have accumulated 43.8 million hectares of man-made forests by 1990, 73% of which are from the Asia-Pacific region, 33 in the Caribbean tropical region accounted for 20% and in 40 countries in tropical Africa 7%. Tropical forest survival rate is estimated as ...