甘肃省民勤县土地荒漠化动态监测研究

甘肃省民勤县1994年和1998年两期TM影像解译的结果表明:在民勤县,荒漠化局部治理与荒漠化大面积剧烈发展同时并存。民勤绿洲外围荒漠化治理成效显著,4年中灌木林地明显增加,但绿洲外围的低盖度草地沙化也进一步加剧,流沙的面积明显增加,沙质低盖度草地和盐渍低盖度草地减少的幅度分别达13.8%和11.5%,而流沙则增加了0.3%。水资源不合理利用、绿洲边缘随意开荒和草场过度放牧及过度樵采是该县荒漠化的主要动因。位于巴丹吉林沙漠危害民勤绿洲风沙前沿地带的民勤西沙窝,几十年来的风沙危害治理,使该区的荒漠化基本得到了逆转。4年中耕地、林地等都稳步增加,但由于地下水位下降,植被衰退导致的再沙化将是今后荒漠化的主要表现。文中也提出了民勤县荒漠化综合防治的思路。

Research on Desertification Dynamic Monitor in Minqin County

Use GIS and RS, analysis the TM images in 1994 and 1998 about Minqin County. The result show: somewhere in Minqin county desertification has been controlled, the same time somewhere been exacerbated. Around the Minqin oasis desert control is successes, the area of shrub become bigger. But beyond the oasis, the area of sandy grassland and salt grassland have been reduced 13.8% and 0.3%, the flow dune increased 0.3%. The reason of desertification is irrationality use water resource, overly graze on the grassland and overly bring under cultivation around the oasis. In the model area, Xishawo of Minqin, locates the tile of badanjiling desert and before Minqin oasis, after some years control, the land, and the forest are stable increased, the desertification in model area has been reversed. In the future, along with the fall of ground water, the degeneration of vegetation should be the major exhibition of desertification in Minqin County. We provide some advice for the control of desertification in Minqin County.