基于NDVI的新疆玛纳斯湖湿地植被覆盖度变化研究

以2000年、2006年、2010年、2013年和2016年5期的Landsat遥感影像为基础数据源，基于像元二分模型反演了玛纳斯湖湿地植被覆盖度。通过动态度、转移矩阵对比不同时期各等级植被覆盖度的转化比例，分析植被变化的驱动力。结果表明： 2000-2016年，玛纳斯湖湿地植被覆盖度总体较差。极低植被覆盖度所占比例由19.6%增加到了46.3%，低植被覆盖度所占比例由60.6%减少到了28.7%，中植被覆盖度所占比例由9.4%减少到了4.6%，中高植被覆盖度相对变化较小，所占比例由2.9%增加到4.2%，高植被覆盖度所占比例由7.4%增加到16.2%。整个地区的荒漠盐碱土地和农田土地利用面积在逐渐增加，影响植被覆盖度和湖泊萎缩干涸的主要因素是过度利用水资源和人类活动对主要源流流域土地资源的大规模开发。

The vegetation coverage change based on NDVI of the wetland by Manas Lake,Xinjiang

Based on Landsat remote sensing images of 2000, 2006, 2010, 2013 and 2016, the vegetation coverage of the wetland by Manas Lake were retrieved based on the dimidiate pixel model. Through dynamic degree and transfer matrix analyses, the conversion ratio of vegetation coverage in different times were compared, and the driving force of vegetation change was analyzed. It was found that:the vegetation coverage in the wetland was generally poor in 2000-2016; the extra-low vegetation coverage ratio had increased from 19.6% to 46.3%, the low vegetation coverage ratio had decreased from 60.6% to 28.7%, the middle vegetation coverage ratio had decreased from 9.4% to 4.6%; the middle and high vegetation coverage ratio was relatively changed less, with the proportion increasing from 2.9% to 4.2%, the high vegetation coverage ratio had increased from 7.4% to 16.2%; as a whole, the utilized land in the areas of desert saline land and farm land is gradually increasing; the main factors that affect vegetation coverage and shrinkage of lakes are the large-scale exploitation of land resources in the main stream basin by over-utilization of water resources and human activities.