湖泊是干旱区气候与环境变化的敏感指示器,了解干旱区湖泊的空间分布和变化特征,有利于正确分析和评估气候变化和人类活动对干旱区水资源的影响。采用2010年的Landsat遥感数据资料,对新疆、中亚五国及其毗邻高山地区的湖泊制图,并分析该区域内湖泊的数量、面积的时空分布特征。研究表明:①2010年研究区域内大于0.01 km2以上的湖泊总数为30 952个,总面积为496 674.35 km2,其中哈萨克斯坦北部、阿尔泰山地区和昆仑山南麓是湖泊富集的地区。②湖泊数量与湖泊面积呈幂指数关系,湖泊面积每升高一个10的量级,该量级内的湖泊数量下降4~6倍,湖泊面积增加1~2倍,与全球的湖泊分布相比,属于湖泊分布相对稀少的地区。③湖泊数量在纬度带的空间分布相对均一,大型湖泊集中分布在41°~44°、46°和48°~50°的纬度带上;低海拔地区的湖泊数量多,面积大,高海拔地区湖泊数量多,面积小;山区、河谷湿地和哈萨克斯坦北部草原湖泊数量多;荒漠区湖泊分布稀少。④近20 a来,高山地区湖泊与平原地区湖泊呈相反的变化模式,高山地区湖泊处于稳定或快速扩张态势,而平原地区的湖泊剧烈萎缩。
Lake is a kind of sensitive indicator of climate and environmental changes. Mapping of the area and monitoring of the change of lakes in arid regions are essential to estimate the effects of climate change and human activities on water resources. In this paper,the change of area of the lakes in Central Asia was mapped with the Landsat images in 2010,and the spatial distribution of number and area of the lakes was also discussed. The results were as follows:( 1) There were 30 952 lakes larger than 0. 01 km2in Central Asia in 2010,and their total area was 496 674. 35 km2;( 2) There was a power exponential relationship between number and area of the lakes.If the lake size was increased from one logarithmic size class to the next bigger one,the lake number was statistically increased by 4- 6 times,and total area of the lakes was enlarged by 1- 2 times. Compared with the lakes in other regions in the world,the density of lakes in Central Asia was relatively low;( 3) The latitudinal spatial distribution of the lakes was relatively uniform,and the large lakes were mainly distributed in the latitudinal zones of41°- 44°N,46°N and 48°- 50°N. The lakes in the low-altitude regions were more,and their areas were large.However,the lakes in the high-altitude regions were also more,but their areas were small. The lakes in the mountainous regions,valley wetlands and steppes in north Kazakhstan were more than those in deserts;( 4) In recent 20years,the alpine lakes were stable or in an expansion trend,but areas of the lakes in plains were sharply reduced.