基于GIS和RS的雅鲁藏布江中游地区荒漠化动态变化研究

选取1988年TM、2000年ETM以及2007年的ALOS影像数据为主要数据源,对雅鲁藏布江中游地区荒漠化动态变化进行了研究。结果表明:近20年沙质荒漠化经历了1988—2000年沙质荒漠化总面积呈上升趋势和2000—2007年沙质荒漠化总面积呈下降趋势两个发展阶段,但是总体上却是呈上升趋势,其中轻度、中度和重度沙质荒漠化土地增加的速度分别为1.93%、1.50%和3.20%,表现为沙质荒漠化土地总面积在较大幅度增加的同时荒漠化程度的提高速度相当快;沙质荒漠化的形成,一方面与青藏高原高寒干燥的气候和脆弱的植被生态系统有关,另一方面也受人为活动的驱动。该研究可为该地区荒漠化治理提供科学依据。

Research on the Dynamic Change of Land Desertification in the Middle Reaches of Yalu Tsangpo River Based on GIS and RS

1988 TM,2000 ETM and 2007 ALOS images are selected as the main source of data to conduct the research of the dynamic changes of land desertification in the middle reaches of Yalu Tsangpo River.Results show that sandy desertification development in recent 20 years experienced two stages: in 1988-2000 period,the sandy desertification area shows the ascendant trend and in 2000-2007 period,the sandy desertification area declines;but in general,the trend is ascendant.The increasing speed of mild,moderate and severe sandy desertification is 3.20%,1.93% and 1.50% respectively,which means the sandy desertification area is greatly increased with the increase of desertification degree.The formation of sandy desertification is,on one hand,tightly related to the alpine dry climate and fragile vegetation ecosystem of Qinghai-Tibet Plateau,and,on the other hand,affected by human activities.The analysis of the causes of sandy desertification changes can provide scientific basis for the control of desertification.