长江源区荒漠动态遥感监测及驱动力分析

Desert Dynamics Monitoring by RS and Its Driving Factors in Source Region of Yangtze River

利用遥感和GIS空间信息分析技术,以长江源地区的4期遥感数据为主要信息源,将荒漠分为高寒荒漠、裸岩石砾地、戈壁、沙地、裸土地、盐碱地,通过目视解译提取了长江源区4期荒漠信息,在此基础上进行荒漠动态变化及驱动力分析。结果表明,长江源区荒漠分布范围较广,荒漠面积占源区总面积的28%左右,荒漠中以高寒荒漠、裸岩石砾地、戈壁、沙地为主,其次是裸土地和盐碱地。近30 a来的变化趋势是20世纪70年代中期到1990年荒漠化发展较快,荒漠面积增加了43 935.00 hm2,1990年到2000年荒漠面积减少了32 821.28 hm2,2000年到2005年荒漠面积增加了29 611.30 hm2。

A RS database derived from Landsat MSS in middle 1970＇s, Landsat TM in 1990, Landsat ETM＋ in 2000 and Landsat TM in 2005 was employed to analyze the desert sptio-temporal variation in source region of Yangtze River by GIS technique. The desert in study area was classified into six types： alpine desert, naked-rock desert, Gobi, sandy desert, bare land, and saline-alkaline land. Deserts cover the most area of source region of Yangtze River, occupying 28% of the total area. Alpine desert, naked-rock desert, Gobi, and sandy desert are dominant; bare land and saline-alkaline land are second. The evolution of desert developed positively from middle 1970＇s to 1990, with an increase by 43 935 hm^2, adversely from 1990 to 2000 with a decrease by 32 821.28 hm^2, again with an increase of 29 611.30 hm^2 from 2000 to 2005.