摘要
为提高河南省水土保持小流域划分工作的准确性与高效性,以河南省卢氏县、宜阳县和太康县分别作为山区、丘陵区和平原区的代表,基于分辨率12.5 m的DEM数据,利用Arc Hydro模型提取研究区河网信息,采用河网密度法研究集水面积阈值和河网密度、河网密度二阶导数的关系曲线,选取最优的集水面积阈值。结果表明:河网密度法可以避免传统方法在选取阈值时的盲目性与主观性,更加科学合理;不同地形的区域阈值选取也大不相同,卢氏县、宜阳县和太康县的最优阈值分别是50000、35000和30000,这说明在河南省小流域划分工作中应考虑到不同地形在河网提取时的影响,以保证小流域划分工作的精度。
In order to improve the accuracy and efficiency of small watershed division of soil and water conservation in Henan Province,taking the counties of Lushi,Yiyang and Taikang of Henan Province as the representatives of mountainous area,hilly area and plain area,the paper extracted river network information in the study area by using Arc Hydro model based on DEM data with resolution 12.5 m.It studied the relation curve between the catchment area threshold value and the density of river network and the second derivative of the density of the river network by using the river nerwork density method and selected the optimal catchment area threshold value.The outcomes show that a)the density method of river network can avoid the blindness and subjectivity of the traditional method in selecting the threshold value and is more scientific and reasonable and;b)the selection of regional threshold value for different landform is also very different.The optimal threshold values of Lushi,Yiyang and Taikang counties are 50000,35000 and 30000 respectively,which indicates that the influence of different landform in river network extraction should be taken into account in the small watershed division in Henan Province,so as to ensure the precision of small watershed division.
作者
吴鹏
王伟
王媛
贾智乐
WU Peng;WANG Wei;WANG Yuan(Henan Provincial General Monitoring Station of Water and Soil Conservation,Zhengzhou,Henan 450003,China;Henan Water Resources Survey.,Ltd.,Zhengzhou,Henan 450003,China)
出处
《中国水土保持》
2023年第2期20-23,I0007,共5页
Soil and Water Conservation in China
