人类活动和自然因素在阿拉善盟荒漠化过程中的相对作用

Relative roles of human activities and natural elements in the desertification process in Alxa League

使用MODIS和TRMM遥感资料定量研究荒漠化两大驱动因素的相对作用,得到以下结果：近些年荒漠化加重区域主要分布在额济纳旗和阿拉善左旗,零星地分布在阿拉善右旗,荒漠化加重区域占阿拉善盟土地总面积的22.6%;在荒漠化加重区域,人类活动对植被生长的影响是负面的,即人类活动促进了该区域荒漠化加重.将2000-2012年分为3个时段：第1时段（2000-2004年）、第2时段（2005-2008年）和第3时段（2009-2012年）,第1-2时段和第2-3时段,人类活动是引起阿拉善荒漠化加重的主导诱因,相对作用达到60.6%-62.1%.

Using MODIS and TRMM data,the relative roles of two main drivers in the desertification process has been analyzed and discussed and it was found that the hot spots of land degradation shared 22.6%of Alxa League desertification area,using the trends of annual sum NDVI.The biggest desertification proportion occurred in Ejina Banner,followed by Alxa Left Banner and Alxa Right Banner.Human affects,taken as a whole,were a negative impact on vegetation growth and quickened the formation and development of desertification in hot spots of land degradation.The study period was divided into three phases,i.e.,the first（2000-2004）,the second（2005-2008） and the third（2009-2012）.From the first phase to the second and from the second to the third,the relative human role occupied a dominant position and the relative role value was between 60.6%-62.1%.