用归一化水体指数NDWI和监督分类中的最大似然法对鄱阳湖入江通道1989年、1996年、1999年、2006年、2010年、2014年的6期枯季Landsat卫星影像进行长时间序列的研究分析,得到水域、滩地、植被面积的变化情况.分析结果表明:其中水域面积从85 km^2增加到108 km^2,其趋势是先增后减再增;滩地面积从189 km^2减少到150 km^2,其趋势是先减后增再减;植被面积从37 km^2增加到53 km^2,其趋势是先增后减再增再减.分析可知鄱阳湖入江通道在25年间的变化受自然、人为等多方面因素影响;其中长江三峡水利枢纽工程、人工挖沙等人为因素对其变化的影响最大.
In this paper, the method of maximum likelihood supervised classification and NDWI is used to analyze the long time series Landsat satellite images of the channel between Poyang Lake and the Yangtze river, and the change of beaches, waters and vegetation area are obtained by studying the six phase images in 1989, 1996, 1999, 2006, 2010 and 2014. The results show that the beaches, waters and vegetation of the channel between Poyang lake and the Yangtze river had changed, with the water area increasing from 85 km^2 to 108 km^2 with fluctuations; the beaches area decreasing from 189 km^2 to 150km^2 with fluctuations; the vegetation area increasing from 37 km^2 to 53 km^2 with fluctuations. The analysis shows that these changes of the channel between Poyang Lake and the Yangtze river in the past 25 years are influenced by nature, humanity and other aspects, and the human factors of Three Gorges project and artificial sand excavation have the greatest impacts on its changes.