Land Cover Changes in Qaidam Area from 2000 to 2008

Qaidam Basin is one of the largest arid regions in the middle latitude Asia, which is surrounded by high mountains. The ecosystem of this region is fragile due to limited annual precipitation amounts in the interior basin and large temperature differentia between winter and summer on the surrounding mountains. Several researchers have reported vegetation cover in this area had degraded in the past several decades with the climate changes and human activity. In this study, we use 1-km resolution moderate-resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) to explore land cover changes in Qaidam area from 2000 to 2008 based on combine decision tree (DT) and spectral angle (SA) classification methods. An accuracy test illustrates the classification are of credible accuracy for both time periods. Analysis results indicate that vegetation cover has increased for the past 9 years in the Qaidam Area, and lake areas and multi-year snow/ice cover areas have also increased significantly, while barrenland has decreased.