基于SPOT5和北京一号小卫星数据的北京北部山区土壤侵蚀变化研究

AN ANALYSIS OF SOIL EROSION CHANGE IN THE NORTHERN MOUNTAINOUS AREA OF BEIJING BASED ON SPOT 5 AND BEIJING-1 SATELLITE

利用2004年10月SPOT5卫星影像及2007年9月北京一号小卫星多光谱和全色影像，以植被覆盖度、坡度、土壤可蚀性和土地利用4种影响因子作为辅助数据，进行土壤侵蚀信息提取。利用所提取的信息，分析2004—2007年北京北部山区土壤侵蚀在空间、面积上的变化状况、强度类型转化状况以及变化的驱动力。分析结果表明，北京北部山区土壤侵蚀主要为轻度侵蚀与中度侵蚀，以轻度侵蚀为主；2004—2007年北京北部山区虽然局部地区土壤侵蚀强度增强，但土壤侵蚀总面积减少，大体上呈中度→轻度→微度发展趋势，总体状况得到明显改善。

In this paper, multispectral and panchromatic images of SPOT 5 in October 2004 and Beijing - 1 satellite in September 2007 were selected to extract the information of soil erosion, with four factors, namely the vegetation coverage, slope, soil erodibility and land use, as the supplemental data. The changes of soil erosion in such aspects as distribution, area and intensity type and the driving force of these changes were analyzed in the northern mountainous area of Beijing during the period of 2004 -2007. The results show that soil erosion was mainly light erosion and subordinately moderate erosion. Although the soil erosion intensity increased in some places, the total erosion area tended to decrease. The general erosion trend was moderate → light → slight in the northern mountainous area of Beijing in the period of 2004 -2007. The overall situation had been markedly improved. Soil and water conservation efforts made by Beijing Municipal Government in recent years have proved to be highly effective.