高寒草甸地区沙漠化发展过程及成因分析——以黄河源区玛多县为例

Development and Cause of Aeolian Desertification in Alpine Region—In Case of Maduo County in Yellow River Source Area

遥感监测和野外调查研究结果表明:玛多县的沙漠化经历了由迅速发展到急剧逆转的过程,其中,20世纪80年代到2000年是沙漠化迅速发展的时期,沙漠化土地面积从1987年的12 827.6km2增加到16 330.7km2,达到全县土地总面积的64.7%,而在此后的6a里,沙漠化状况得以有效逆转,在2006年,沙漠化土地下降到12 977.2km2,年均逆转面积为559km2;研究区沙漠化发生、发展的主要原因是气候变暖引起的冻土退化,以及随之引起的表土干旱化、草场退化、鼠害等;人类活动虽然在研究区沙漠化发生、发展过程中没有起到主导作用,但是可以通过以草定畜、围栏、灭鼠等措施有效控制沙漠化的发展,并使其得到逆转。

The results from remote sensor process in the study area can be distributed monitoring and field survey show that aeolian desertification into two stages： the developing stage from late 1980s to 2000, and the reversing stage form 2000 to 2006. Aeolian desertification area in the study area was 12 827.6 km^2 in 1987, and reached up to 16 330.7 km^2in 2000 which occupied 64.7% of total area of the county, then dropped down to 12 977.2 km^2 in 2006 ; Aeolian desertification in study area mainly results from climate warming which deteriorate the frozen soil and lead to the drought of topsoil, grassland degradation and ro- dent pesticide; human action has not dominantly resulted in the aeolian desertification, however, can control and reverse it effectively by some measures such as confirming livestock number according to the carry capacity of grassland, enclosing grassland and extinguishing rodents pesticide and so on.