基于RS和GIS的干旱河谷范围界定方法研究

DEFINITION DRY VALLEYS SCOPE BY RS AND GIS

以10月份前后的1～2个月内的植被变化为主要依据,以RS和GIS为平台,选取Landsat遥感影像数据,通过对植被和裸地进行分类,提取植被覆盖变化范围,结合平均谷坡坡度大于25°的谷坡高程图,界定出大渡河上游干旱河谷的分布范围,并将该方法应用于大渡河上游干旱河谷范围的界定.结果为:大渡河上游分布的干旱河谷长约355.4km(包括两河口足木足河段),总面积约585.8km2.通过遥感图像和数字高程模型(DEM)来界定干旱河谷范围的方法,对于基础数据资料相对缺乏的川西地区的生境综合治理以及区域可持续发展具有实际指导意义.

Dry valley scope was defined by RS and GIS in this study.The essential criteria was changes in vegetation cover before and after October.The scope of dry valleys was determined,by taking RS and GIS for platform and remote sensing satellite image data from September to October from Landsat.Elevation map was applied in combination with RS and GIS.It was found that dry valley parameters for Dadu upriver were： length 355.4 km,area 585.8 km2.This method to define dry valley scope would be very meaningful for regions lacking such information,and useful to manage ecological environment.