基于GIS和DEM数据的流域水系提取与优化分析

相比野外测量和大比例地形图为主的流域水系提取方法,运用GIS技术和DEM数据的数字化提取更为便捷、高效.基于ArcGIS中的3D Analysis和Hydrologic Model模型,研究山区地形条件下的DEM数字流域水系提取.结果表明,研究区提取水系总长度为350.05 km,结果较好,尤其大中型河道长度的偏差仅在...

An Analysis of Basin River Extraction and Optimization Based on GIS and DEM Data

Based on the basin river extraction methods of field measurements and large-scale topographic map,using digital GIS and DEM data extraction is more convenient and efficient.Based on 3D Analysis and Hydrologic Model of ArcGIS,the basin river DEM digital extraction is researched under the condition of mountainous terrain.The results show that the extraction of basin river is a total length of 350.05 km in the study area,especially large and medium-sized river length that deviation is only within 7.5%.Moreover,the extraction results are optimized,the accuracy influence of different grid number andthreshold value to the extraction are analyzed,and it isfound that the triple polynomial function is moresuitable for the relationship between the grid number and distance error.Hydrological information such as the river length,junction area and branch number is calculated,and mathematical function fitting is used.It is concluded that the threshold value is set to 12000,the water extraction is most consistent with the actual effect of basin river.The digital extraction method and optimization of mountain basin river can not only provide technical support and reference for the extraction,but also offer scientific guidance for the difference analysis between the digital extraction and measured one.