ASTER数据在寒区流域水系参数化中的应用——以木扎尔特流域为例

Application of ASTER data in parameterizing Water System in Cold region——Case Study for Muzaerte Valley

介绍了以ASTER遥感数据为信息源,通过遥感图像处理技术自动提取天山南麓木扎尔特流域的DEM.根据已建立的数字高程模型,在A rc/Info模块支持下,自动提取流域水系的参数,如栅格水系流向、自动生成河网等,并探讨了寒区流域水系的参数化过程.结果表明,部分冰川覆盖的槽谷地形(U形)区被误判为流域水系,其误差率为21.1%;经过剔除冰川覆盖区误判以后的水系再与来自1¨100 000地形图的水系长度相比,误差仅为0.9%;另外,由于两者数据源的获取时间不同,河流位置也略有差异,这可能与河道的摆动或改道相关,但来自ASTER影像提取水系更能反映河道的近期信息.总体上讲,ASTER数据能适合寒区流域水系参数化的需要,为水文定量化研究及应用提供数据基础.

The DEM in Muzaerta valley of Tianshan is automatically extracted from ASTER data by using the remote sensing technique. Based on the DEM, parameters of the water system, such as flowing direction, flowing network, and so on, are extracted automatically supported by the Arc/Info software, and the parameterized process of the water system in cold region is discussed. The result shows that the parts （U-shaped valley） covered by glaciers are misidentified as the water system with an error rate of 21.1%. However, after eliminating the misidentification, the error rate is only 0. 9% compared with the drainage system derived from topography at a scale of 1 ： 100 000. There is a little difference in their locations of the two rivers because of the migration of river. The water system derived from ASTER images can well reflect the last information of the river. As a whole, the ASTER data can meet the needs of parameterization.