摘要
针云南省楚雄地区为研究区域,采用1:25万水系数据为参照,基于资源三号测绘卫星DSM(ZY-3DSM)数据自动提取水系,并从河流分支点和水系因子两方面分析其精度,再与SRTM DEM提取的水系进行比较。结果表明:(1)从河流分支点来看,ZY-3 DSM提取的水系精度普遍高于SRTM DEM,在中海拔丘陵和中海拔台地上点位精度比后者高50%以上,在低海拔平原和中海拔平原上点位精度比后者高25%以上;(2)就水系长度和分级而言,ZY-3 DSM提取的水系总长度比SRTM DEM约长15%,一级和二级河流数目比后者多18%;(3)从水系密度和河网套合差来看,ZY-3 DSM提取水系与1:25万水系吻合度较好,水系密度相似度高于SRTM DEM约3倍,河网套合程度前者高于后者45%。总之,基于ZY-3 DSM提取的水系精度较高,完全符合测绘标准规范,且各方面均优于SRTM DEM提取的水系。
To investigate the accuracy of automatically extracted river network based on ZY-3 DSM, in this paper,the Chuxiong of Yunnan was selected as a study area, the 1：250 000 river network was taken as the reference, its accuracy in terms of the river branch points and river system factors were evaluated, and its accuracy with river system from SRTM DEM were compared. The results show：（1） the accuracy of the river system, in view of river branch points, based on ZY-3 DSM is better than SRTM DEM. The former is even more than 50% betteron the mid-elevation hills and mesas, and is 25% better on the low-elevation plains and the mid-elevation plains;（2） the river system from ZY-3 DSM is 15% longer than the total river length and 18% more than the number of the 1 and 2 level riversof classification from SRTM DEM;（3） the river system from ZY-3 DSM has a good fit with 1：250 000 river network, in view of river density and overlap differences. The similarity of its river density is almost 3 times of that of SRTM DEM, and the river overlap＇s degree is 45% better than the latter. In words, the extracted river system from ZY-3 DSM has high accuracy than that from SRTM DEM.
出处
《地理信息世界》
2016年第2期101-106,共6页
Geomatics World
基金
卫星测绘技术与应用国家测绘地理信息局重点实验室课题项目(KLSMTA-201509)
卫星测绘技术与应用国家测绘地理信息局重点实验室课题项目(KISMTA-201302)资助
