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基于GIMMS/NDVI数据对诺敏河流域1982-2006年间植被覆盖的时空演变特征进行了研究,并结合SCS模型模拟地表径流,在流域和像元尺度分析植被NDVI变化与径流的关系。研究表明:诺敏河流域植被NDVI值较高,但25a间整体呈下降趋势,NDVI减少的区域占总面积的82.5%,植被覆盖有所降低;NDVI空间差异明显,NDVI的高值区主要分布在中上游林区,而耕地分布较多的下游地区NDVI值相对较低。流域尺度上植被NDVI与径流不具有明显的相关性。但从像元尺度来看,植被NDVI和径流的正相关和负相关共存,流域不同空间位置的植被变化与径流的关系并不一致。
Based on the GIMMS / NDVI data, the temporal and spatial evolution characteristics of vegetation cover in the Nuomin River Basin during 1982-2006 were studied. The SCS model was used to simulate the surface runoff. The relationship between vegetation NDVI variation and runoff was analyzed on the basin and pixel scale. The results showed that the NDVI value of Nomin River Basin was higher than that of the other two years, but the overall NDV decreased in 25 years. The area of NDVI decreased accounted for 82.5% of the total area, and the vegetation coverage decreased. The NDVI spatial difference was obvious, and the NDVI high value area was mainly distributed In the middle and upper reaches of the forest area, NDVI values in the downstream areas with more cultivated land are relatively lower. There is no obvious correlation between vegetation NDVI and runoff in watershed scale. However, from the pixel scale point of view, the positive and negative correlations between vegetation NDVI and runoff coexist. The relationship between the vegetation change and runoff in different spatial positions of the watershed is not consistent.