基于北京1号小卫星的全国沙漠与沙漠化土地监测研究

利用2006和2007年北京1号小卫星多光谱数据,对中国四大沙地和八大沙漠地区沙漠和沙漠化土地分布状况及其动态变化进行研究。结果表明:2007年研究区内沙漠和沙漠化土地总面积为69.18×10⁴km²,占研究区总面积的25.03%,其中重度区面积占14.88%,中度区占5.10%,轻度区占5.05%。2006~2007年研究区内共有440块图斑发生变化,总变化面积为876.41km²,沙漠化土地增加面积47.57km²,减少面积为373.39km²。沙漠化土地类型间的转换面积为455.45km²,主要以轻度和中度沙漠化土地之间相互转化最为明显。

Study on Monitoring of Desert and Sandy Desertification Land in China Using Images of Beijing-1 Small Satellite

Beijing-1 multispectral data, with advantages of short revisit period and the large area collection capability of 32 m resolution, 600 km width imaging swath and more than 4 000 km stripe, is a new prior source of remote sensing data in monitoring desert and sandy desertification land. This paper introduced the workflow and the key technologies to monitor the desert and sandy desertification land more rapidly and frequently in whole country based on Beijing-1 multispectral data.Two periods of Beijing-1 near-anniversary images in 2006 and 2007 were used to analyse the distribution and change of desert and sandy desertification land. The study area includes Hulunbuir Sandy Land, Horqin Sandy Land, Otindag Sandy Land, MuUs Sandy Land, Hoboq Desert, Tengger Desert, Badain Jaran Desert, Ulan Buh Desert, Qaidam Desert, Kumtag Desert,Gurbantunggut Desert, Taklimakan Desert and so on. The result showed that the total area of the desert and sandy desertification land added up to 691 752km² in 2007, accounting for 25.03% of the whole region. The proportion of severe, medium and slight land was respectively 14.88%, 5.10% and 5.05%. They mainly distributed in Xinjiang Uighur Autonomous Region and Inner Mongolia Autonomous Region, whose area accounted for 61.16% and 27.84% of the total area of the desert and sandy desertification land respectively. There were 22 counties or banners where the area of the desert and sandy desertification land was over 50% of its total region area. Moreover, there were 33 counties or banners where the area of the severe land had exceeded 10% of its total region area.There were 440 patches changed from 2006 to 2007, which added up to 876.41 km², mainly in the edge of desert or sandy land. The area of the desert and sandy desertification land to the non-sandy land was 373.39 km², of which mostly being converted into farmland, vegetation region, water body, construction land and so on. Contrariwise, the area changed from non-sandy to the sandy land was 47.57 km², mainly from farmland or vegetation region to the slight land. So t 325.82 km² of desert and sandy desertification land decreased from 2006 to 2007. In addition, the transformation area among the three level lands was 455.45 km², of which the transformation between medium and slight land was obvious.