近40年西藏那曲南部湖泊变化及其成因探讨  

Lake Change in Past 40 Years in the Southern Nagqu District of Tibet and Analysis of Its Driving Forces

作　　者：黄卫东[1,2] 廖静娟[1] 沈国状[1] 

机构地区：[1]中国科学院对地观测与数字地球科学中心,北京100094 [2]中国科学院研究生院,北京100049

出　　处：《国土资源遥感》2012年第3期122-128,共7页Remote Sensing for Land & Resources

基　　金：973计划项目"多平台遥感观测科学实验与环境信息模拟"(编号:2009CB723906)资助

摘　　要：以遥感图像、SRTM的DEM数据为数据源,通过人工目视解译的方法提取并计算了1970—2010年那曲南部地区12个湖泊面积,并结合DEM数据计算其中9个湖泊1990—2010年间水位变化情况;然后分析该地区降水量、气温、最大潜在蒸发量、冻土、冰川雪线的变化规律;计算湖泊变化与气候变化之间的相关性,并以简单的水文模型分析了湖泊变化的原因。结果显示:12个湖泊中除了格仁错面积减少以外,其他湖泊面积在40 a间都处在增长状态,其中湖泊面积增长主要发生在2000—2010年,这期间12个湖泊增长总面积达743.88 km2,占40 a总增长面积的63.95%;9个湖泊的水位也呈上升趋势。造成这些湖泊面积增长的主要原因是近45 a气温上升造成的冰雪、冻土融化,降水量增加,而且该地区蒸发量呈减少趋势。This study was based on remote sensing images and DEM of SRTM. Areas of twelve lakes in southern Nagqu district in the period of 1970 -2010 were derived by visual interpretation, and levels of nine lakes in the period of 1990 -2010 were calculated using lake area data and DEM. Then the change regulations of precipitation, temperature, evaporation, frozen ground, glacier and snow line in this region were analyzed. Correlation analysis between the lake area and the climate change was performed, and the causes of lake change were studied on the basis of a simple hydrological model. According to the results, all lake areas increased during the last 40 years except for Gyaring Co, and the lake area expansion notably happened during 2000 -2010, with the total increased area of all 12 lakes in this decade being 743.88 km2, which accounted for about 63.95% of all the increased area in the past 40 years; in addition, the levels of the nine lakes tended to rise too. The main reasons for lake change are attributed to the melting of snow cover, glaciers and frozen grounds and the increasing of precipitation caused by climate warming in the past 45 years. Besides, the decreasing evaporation is also a reason for lake expansion.

关 键 词：湖泊变化 气候变化 冻土冰川雪线变化 西藏那曲 遥感 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置]