东北平原西部沙地沙质荒漠化的遥感监测研究

东北平原西部沙地位于欧亚大陆中纬度巨型沙带的东部边缘，为我国沙质荒漠化土地的东缘，沙质荒漠化景观日益明显，前景令人勘忧。本文利用TM数据分析了区域荒漠化观特征与土地荒漠化的特征，从机理上认识了区域上的土地荒漠化发生过程；在此基础上以目前生态系统没有产生明显退化的生态状况作为基准，采用相对基准的办法，利用ONOAA／AVHRR数据，确定了植被指数荒漠化监测指标；对荒漠化的动态变化及驱动因子进行了分析。研究认为区域荒漠化监测应当以全球常用多种分辨率的遥感数据为基础，在认识荒化发生机理之后进行监测与评估，在资料获取、分类分级和荒漠化监测的技术路线全球应有一个相对统一的标准，使评价的结果具有可比性。东北平原西部沙地的景观特征、沙质荒漠化程度、沙质荒漠化发展方式等具有明显的区域差异，二十世纪90年代沙质荒漠化发展速度很快，但区域差异很大，这种区域差异与人口增长、滥垦和滥樵具有很强的一致性。

A Study on Monitoring Sandy Desertification in Sandy Land of West Northeast China Plain

Sandy Land of West Northeast China Plain lies in the eastern fringe of huge sandy belt of middle latitude in Eurasia Continent and is also the eastern fringe of sandy desertificartion land. Now sandy desertification landscape becomes very obvious, and we are very anxious for this situation. According to TM data, the landscape patterns and desertification features are analyzed and the mechanisms of sandy desertification process are analyzed. According to the VI index of desertification degree, the dynamic change of desertification is detected based on NOAA/AVHRR data and its driving forces is analyzed. It can be concluded that desertification monitoring should be conducted based on commonly used multi-resolution RS data, and there should be a relatively uniform criterion to data, types, grades and methods for monitoring desertification so that the results can be compared all over the world. The regional differences are very obvious in landscape patterns,desertification degree, development modes in this region. In 1990s sandy desertification developed rapidly and the regional differences which are consistent with the population growth, irreasonable cultivation and overgrazing are great.