青藏高原近25年来主要湖泊变迁的特征

青藏高原分布有青海湖、纳木错、色林错3个特大型湖泊和扎日南木错、当惹雍错、阿牙克库木湖、班公错、哈拉湖、鄂陵湖、羊卓雍错、扎陵湖、赤布张错、乌兰乌拉湖、昂拉仁错11个大型湖泊。通过对20世纪70年代中期的MSS图像和90年代末期—21世纪初期的ETM 图像的解译,对近25年来青藏高原重点湖泊的变迁进行了分析。研究结果表明,哈拉湖、鄂陵湖面积相对稳定;青海湖、扎日南木错、当惹雍错、阿牙克库木湖、扎陵湖、乌兰乌拉湖等8个湖泊的面积都有不同程度的缩小,其中青海湖、乌兰乌拉湖面积减少最多,分别为60.60km2、59.80km2;纳木错、色林错、班公错3个湖泊的面积都有不同程度的增加,其中色林错面积增加最多,达140.52km2。重点湖泊的变迁分析为研究青藏高原的湖泊演化和气候、环境变迁提供了新资料。

Characteristics of the change of major lakes on the Qinghai-Tibet Plateau in the last 25 years.

On the Qinghai-Tibet Plateau there are three superlarge lakes,the Qinghai Lake,Nam Co and Siling Co,and eleven large lakes,the Zhari Nam Co,Tangra Yumco,Ayakkum Lake,Bangong Co,Har Lake,Ngoring Lake,Yamzho Yumco,Gyaring Lake,Chibuzhang Co,Ulan Ul Lake and the Ngangla Ringco.The authors studied the changes of these major lakes in the past 25 years,based on interpretations of the MSS images obtained during the middle 1970s and ETM images obtained in the late 1990s or at the beginning of the 21st century.The study shows that:the areas of the Har Lake and Ngoring Lake have remained relatively stable;the areas of the Qinghai Lake,Zhari Nam Co,Tangra Yumco,Ayakkum Lake,Gyaring Lake,Ulan Ul Lake and Ngangla Ringco have been reduced to varying degrees,of which the areas of the Qinghai Lake and Ulan Ul Lake have decreased most sharply by 60.60 km2 and 59.80 km2 respectively;the areas of the Nam Co,Siling Co and Bangong Co have increased more or less,of which the area of the Siling Co has increased most sharply by 140.52 km2.The analysis on the changes in areas of major lakes has provided new materials for the study of the lake evolution,climatic change and environmental variation on the Qinghai-Tibet plateau.