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一、前言目前在亚洲、非洲和拉丁美洲森林面积平均每年至少缩少一千一百万公顷,而林区的丧失,又以热带森林面积首当其冲,这种惊人速度的不断下降,给人类经济和环境方面造成灾难,而过去这些热带森林是赖以养育人类环境和珍贵用材的主要来源之一。就我国海南岛的热带珍贵用材树种资源而言,也有日益减少的趋势。随着我国社会主义建设事业发展,扩大我国热带珍贵用材树种资源十分必要,除了在当地大力发展外,北移引种也是一条积极的途径。
I. INTRODUCTION At present, the forest area in Asia, Africa and Latin America shrinks by at least 11 million hectares annually on average. However, the loss of forest areas and the tropical forest area bear the brunt. This staggering rate of decline has given humanity and The environment has caused disasters, and in the past these tropical forests were one of the main sources on which the human environment and valuable timber were raised. In terms of tropical precious tree species resources in Hainan Island, China, there is also a decreasing trend. With the development of China’s socialist construction, it is necessary to expand the resources of tropical precious tree species in our country. In addition to the vigorous development in the area, the introduction of the northward migration is also a positive approach.