Aanlysis on the dynamic of lakes in Tibetan Plateau since 1960's

Abstract

Taken the relief maps, MSS images, TM images, ETM images and CBERS images as basic data sources, this paper studied on the dynamic of lakes in Tibetan Plateau since 1960's using RS and GIS technique. The results showed that the increasing area of lakes in Tibetan Plateau in last 50 years is 5760 km2. The change can be divided into two phases: the lake trended to shrink from 1960's to the imddle of 1980's and to spread after that, which is consistent with that change of global climate. The regional difference of lakes in Plateau is obvious: the lakes in Changjiang wateshed, Talimu basin and Qiangtang Plateau represented an increasing tendency after 1980's while that of Chaidamu basin and Hexizoulang region decreased. We also can see that law of lakes change: lakes recharged from precipitation in arid region trended to shrink and the lake recharged form glacier spreaded. The variation leaded the center of gravity of lakes in Plateau to move 21km in the direction of Northwest and the change of lakes in Qiangtang basin played the import role in this process.