中文摘要：

为阐明珠江流域植被覆盖变化的整体状况，基于RS与GIS技术，应用美国国家航天航空局最新的全球植被指数变化研究数据（GIMMS），对珠江流域1982—2003年间的地表植被覆盖的空间分布及时间序列变化进行了综合分析。结果表明：（1）22年来，珠江流域大部分地区的NDVI都呈现不同程度的下降趋势，表明珠江流域植被活动在减弱；（2）从季节变化来看，珠江流域平均植被覆盖除春季呈不显著上升外，其余各季均呈不显著下降趋势；（3）空间上，中下游地区都呈现不同程度的下降趋势，其中珠江三角洲地区达到了极显著水平：而上游南、北盘江流域、右江、左江及郁江流域则呈小显著增加趋势。这种空间异质性是由于城市化过程、农业生产活动、区域气候特征等综合因素作用的结果。

英文摘要：

NDVI is an important index denoting a region＇s vegetation cover. Based on RS＆GIS technology, this paper analyses and illustrates spatio-temporal changes of NDVI in the Pearl River Basin, by using 8 km resolution Global Inventory Modeling and Mapping Studies （GIMMS） Normalized Difference Vegetation Index （NDVI） dataset, monthly from 1982-2003. The main conclusions are： （1） In general, NDVI values show the decreasing trend （no passing the confidence level of 95%） in the Pearl River Basin in recent 22 years （1982-2003）. Suggesting terrestrial vegetation activity in the Pearl River Basin continues to degrade. （2） In spring, NDVI values show the increasing trend （no passing the confidence level of 95%）, but in summer, autumn and winter NDVI values show the decreasing trend （no passing the confidence level of 95%）. （3） In the middle and lower reaches of the Pearl River, NDVI values display the decreasing trend at different confidence level, especially in the Pearl River Delta region displaying the significant decreasing tendency （at the 99% confidence level）. But in the upper reaches, such as Nanpanjiang River, Beipanjiang River, Youjiang River, Zuojiang River and Yujiang River watershed, NDVI values display the increasing tendency （but no passing the confidence level of 95%）. These spatial differences of change tendency in the Pearl River Basin are influenced by rapid urbanization, agricultural activity and climate change （precipitation, temperature change et al.） together.