近10年来金沙江石鼓上游NDVI时空变化研究

为分析过去10余年长江源区保护治理的效果，采用归一化植被指数（EOS/MODIS的NDVI），依据地貌、气候、土壤和植被类型等影响植被生长发育的几个主导因素，对金沙江石鼓以上流域近10 a来的归一化植被指数时空分布特征进行了分析。结果表明，2000~2010年NDVI均值为0.51，总体上呈略增大的趋势。NDVI均值增大的趋势主要表现在低植被覆盖地区，高植被覆盖区变化不大；从高程上看，4 000 m以下地区NDVI值较大且历年变化不大，而4 000 m以上地区NDVI值较小且呈略增大的趋势；从气候和植被类型看，森林植被气候区NDVI均值较大但历年变化不大，草原植被气候区NDVI均值较小，但呈增大的趋势；从土壤类型分布看，森林土壤的NDVI均值较大但无增减性变化趋势，草甸、草原土NDVI均值较低但呈增大的趋势。

Research on spatio-temporal variation of NDVI in upper Jinsha River in recent 10 years

In order to analyze the harnessing and protection effect in the source area of Yangtze River in recent 10 years,EOS/MODIS NDVI data are used to investigate the spatio-temporal characteristics of the regional vegetation in the upper Jinsha River above Shigu gauging station based on several leading factors such as the patterns of geomorphology,climate,soil and vegetation.The results indicate that the maximum NDVI mean value is about 0.51 presenting a little increasing trend from 2000 to 2010.The NDVI has no obvious variation at high vegetated area while it exhibits an increasing trend at low vegetated area.The results also show that there is no obvious variation at low altitude areas below 4 000m while it presents a slight increasing tendency at high altitude areas above 4 000m.From the aspect of climate pattern,the NDVI value is relatively high and there is no obvious variation at forest climate areas while it is low and presents a slight increasing tendency at grassland climate areas.From the aspect of soil pattern,the NDVI value is relatively high and there is no obvious variation at forest soil areas while it is low and presents a slight increasing tendency at Alpine meadow soil areas.