可可西里地区库赛湖变化及湖水外溢成因

以库赛湖研究区地形图、Landsat TM/ETM+和中国环境与灾害监测预报卫星HJlA/BCCD影像为基础,结合五道梁气象站气温降水资料,利用地理信息技术和数理统计方法,对2011年9月可可西里地区库赛湖湖水外溢成因进行分析.结果表明,库赛湖湖水外溢发生在2011年9月20日至30日期间,卓乃湖湖水进入库赛湖是后者发生变化的直接原因,而库赛湖规模近20年来的持续增长,尤其是2006年之后湖泊面积快速增加是其湖水外溢的基础.卓乃湖湖水外泄的主要诱因是区域持续降水,其中8月17日和21日强降水使卓乃湖于8月22日出现漫顶溢流,8月31日至9月5日、9月16日至17日期间两次持续降水导致卓乃湖水量剧增,并在9月14日至21日期间形成洪水.由于水量外泄,卓乃湖面积骤降,截至11月29日,湖泊面积168.07 km2,仅为8月22日湖泊面积的62％,共减少104.88 km2.库赛湖外溢湖水流入海丁诺尔后又进入盐湖,其中海丁诺尔湖水进入盐湖时间介于10月6日至20日期间.外来湖水大量进入导致海丁诺尔和盐湖在10-11月份快速扩大.

Changes of Kusai Lake in Hoh Xil Region and Causes of Its Water Overflowing

Based on topographic maps,Landsat TM/ETM+images,China Environment and Hazards Monitoring and Prediction Satellite(HJ1A/B)CCD images and meteorological materials observed at Wudaoliang meteorological station,we explore the change causes of Kusai Lake using geographical information techniques and mathematical statistics method. The results show that water overflowing Kusai Lake occurred in September 20-30 in 2011, and the direct reason was the flood from Zhuonai Lake flowing into Kusai Lake.In addition, Kusai Lake has been growing in recent decades;especially after 2006 it experienced a quick increase that formed the foundation of lake water overflow.The main factor resulting in the flood from Zhuonai Lake was the steady precipitation.Specifically,the heavy precipitation on August 17 and 21 made Zhuonai Lake water outflow on August 22,2011;then continuous precipitation during August 31 to September 9,16 and 17 subsequently formed a serious flood from September 14 to 21.Accordingly,there was a sudden drop in area of Zhuonai Lake.As of November 29,the lake decreased to 168.07 km 2 (a reduction of by 104.88 km 2 ), accounting for 62%of the area on August 22.The outflow water from Kusai Lake flowed into Haidingnuoer Lake,then into Yanhu Lake.The latter occurred during October 6-20.Due to sudden rapid flow,both Haidingnuoer and Yanhu lakes suffered a quick expansion from October to November,2011.