北京及邻区荒漠化动态演化的遥感综合研究

在研究区野外实际调研和地质、水文、气象、人文环境、土壤质地等荒漠化相关多源信息研究的基础上，对1987、1996年TM及2000年CBERS－1的CCD三个时相遥感影像的处理和分析，提取了研究区荒漠化轻、中、重三个级别的面积，实现了不同时相遥感图像的数据融合与动态对比分析，结合研究区DEM影像分析获得了北京及邻区荒漠化分布和动态演化的时空信息，并由此得出研究区荒漠化存在两种演化类型：在相对干旱的研究区北部（康保至多伦）以面蚀为主体，荒漠化主要受风蚀作用呈面状分布与演化；研究区的西南部以沟蚀为主体，主要受水蚀作用沿洋河、大洋河和永定河呈线状分布与演化。研究区荒漠化总体表现为北强南弱，荒漠化主要发展及演化趋势位于距北京以北百余公里以外的康保至多伦地区，其方向为由西向东，因此，北京地区的荒漠化程度总体低于以北周边地区。

Integral Research on Dynamic Evolvement of Desertification in Beijing and its Neighboring Areas

based on the field investigation and multi-information such as geology, hydrology, anthropogeography, agrotype, vegetation and so on, the TM,and CBERS-1 scenes were analyzed and desertification quantified information was obtained. there are two types of desertification in the research area: surface and line erode, the north of research area is surface eroding and southwest part is line erode, which distributed along the Yanghe and Yongding rivers. The north desertification is stronger than that of the southwest. Main and severe desertification lies in the north of Beijing more than 100km away, direction of evolvement is from west to east. So that the desertification level of Beijing is more light than neighboring areas.