利用1982-2012年的GLASS LAI数据,结合世界粮农组织(FAO)2000年发布的全球生态环境分类图,对亚马逊热带雨林31年的植被变化进行了综合分析,采用点与面相结合的分析方法,全面地反映雨林植被的变化情况。不同于过去研究中固定研究范围或直接研究整个南美洲区域,本文采用动态静态边界相结合的方法,在考虑热带雨林动态范围变化的同时也强调研究区域的内部变化。结果显示,亚马逊热带雨林叶面积指数在31年中整体呈现波动变化,进入2000年以后,热带雨林范围内平均叶面积指数先下降后增加,整体相对稳定。在空间分布上,由于人类毁林开荒,巴西境内的热带雨林以及热带雨林部分边缘地带的叶面积指数在31年中明显下降,热带雨林东南边界持续收缩;除此之外,雨林内部的叶面积指数波动上升,这是受到全球气候变暖的影响。结果与过去的研究进行对比,具有较好的一致性。研究论证了利用具有中国自主知识产权的GLASS LAI数据可以进行长时间序列大尺度的地表植被状况监测。

This paper analyzed changes in the Amazon rainforest from 1982 to 2012 by combining GLASS LAI data with a global ecological classification map published by FAO in 2000. This approach harnesses the advantages of previous studies in terms of precision and time resolution. Moreover, the combination of single-point and analytical methods in the present work can fully reflect the changing status of rainforest vegetation. Previous studies regarded the entire area of South America as a study area; by contrast, the present research applies dynamic and static boundaries and considers the changes in the dynamic range of the rainforest. At the same time, the changes in the targeted research area are emphasized. Results show that the leaf area index of the Amazon rainforest fluctuated over a period of 31 years; after 2000, this index first decreased first and then increased smoothly. In terms of spatial distribution, the leaf area index of the tropical rainforest in Brazil and of other parts of the rainforest margins declined significantly over the same period. Meanwhile, the boundary in the southeast shrank constantly because of the deforestation attributed to human development activities, and the leaf area index of the rainforest interior increased considerably because of global warming. The results of the present work were consistent with those of previous studies; therefore, the current study shows that GLASS LAI, which is subject to the independent intellectual rights of China, can be used to monitor the long-term status of surface vegetation in large areas.