Changes of snow and vegetation coverage of Qilian mountain and water resource in Shiyang river basin over ten years

摘要

Snow coverage plays a significant role in the Earth's water cycle and is sensitive and informative indicators of climate change. Recently, snow coverage in the Qilian Mountain great changed and caused great changes of the ecological environment in the Shiyang River. In this paper, remote sensing imagines were used to calculate the snow coverage, vegetation coverage and water resource. The result indicated that the entire area of the glacier snow was fluctuated on the Qilian Mountains region, having linear and increasing trend from 1997 to 2006. In the eastern and middle of Qilian Mountains, the snow coverage tends to decrease, but in the western, snow coverage tends to increase. As a whole, vegetation coverage is decreasing in Shiyang River Basin. Sparse vegetation and density vegetation were the worst degradation. Water resource in the downriver of Shiyang River (Hongya Mountain Reservoir) decreased.