阿拉湖群面积变化及其成因分析

Area Change and Cause Analysis of Alakol Lakes

基于阿拉湖群1977～2010年间5期遥感资料及湖群周边5个气象站近41年的逐月降水和气温资料，建立了谱间关系法和阈值法相结合的湖泊面积提取模型提取湖群面积，并结合降水气温变化趋势分析了湖群面积变化及其影响因素。结果表明，阿拉湖群1990年后由萎缩向扩张转变，湖泊变化强度由-0．126％增加至0．467％；1966～2006年阿拉湖群气温呈上升趋势，上升幅度为0．32℃／10a，降水量总体呈微弱减少趋势，减少幅度为-2．3mm／10a，自20世纪90年代后，降水量有所增加；气温升高及降水量增加会加速湖群的扩张，而农业灌溉耗水等人类活动能够改变气候因素变化引起的湖群面积扩张程度。

Based on five years remote sensing data in 1977-2010 and nearly 41 years of meteorological data of five weather ,stations surrounding Alakol lakes, the model combined with spectral relations and threshold method were estab lished to extract the area of lakes. The trend analysis of precipitation and temperature change were used to explore the lakes area change and its influencing factors. The results show that Alakol lakes transform from the contraction to expansion since 1990; area change intensity increases from -0. 126% to 0. 467%; lakes temperature appears upward trend from 1966 to 2006; the increase rate is 0. 32 ℃/10a; precipitation shows weakly downward trend and the reduce rate is -2.3 mm/10a; since the 1990s, precipitation has increased; rising temperature and increasing precipitation can aceeler ate the expansion of lakes; human activities such as agricultural irrigation water consumption can change the lakes area dilatation caused by climatic factors.