基于遥感的毛乌素沙地红碱淖面积变化趋势及其影响因素分析

Area variation and controlling factors of Lake Hongjian, Mu Us desert, China based on remote sensing techniques

红碱淖是毛乌素沙地最大的内陆湖泊,是集旅游、渔业和生态湿地于一体的功能区。近年来,红碱淖面积萎缩,影响了其综合功能的发挥。为了查明红碱淖面积的变化趋势及其影响因素,在收集前人资料和研究成果的基础上,借助MODIS遥感数据反演了湖面面积,建立了2000年以来红碱淖面积的时间序列。在分析红碱淖面积的变化特征和影响因素后发现,早期主要受气象因素的影响,湖泊面积呈周期性有规律的变化;后期在自然因素的基础上叠加了上游截流、地下水开采等人为因素的影响,湖泊在周期性变化的基础上总体呈现出萎缩的趋势。

Lake Hongjian is the largest inland lake in the Mu Us desert. It performs functions of tourism, fishery and ecological wetland. In recent years, its comprehensive functions have been influenced with shrinking of its area. In order to make clear the lake area variation and its controlling factors, a time sequence of lake area variation since 2000 was constructed by using previous data and research results and inverting MODIS data to the lake area. The study shows that the lake area variation was controlled by precipitation before 1991. After 1991, the lake area decreased due to less groundwater recharge resulting from lowering of the water table caused by agricultural activities and less surface water recharge due to dam construction in the upstream rivers.