摘要
基于DEM的沟谷提取涉及到DEM网格尺寸和汇流累积阈值这两个重要因素的选择问题。以北京市八达岭小流域1∶1万地形图为数据基础,运用Region Manager 5.0软件、MATLAB 6.0软件和Excel统计功能模块,完成该小流域的沟谷提取工作和数据处理工作。分析得出:随着DEM网格尺寸和汇流累积阈值的增加,所提取的沟壑密度呈现幂函数趋势减小;比较这两个因素,DEM网格尺寸对沟谷提取的精度影响更大。试验发现,以汇流累积矩阵平均值作为依据选择汇流累积阈值较合适。
The DEM-based gully-valley extraction involves two important factors of grid dimension of DEM and accumulated threshold value of confluence.It completes the gully-valley extraction and data processing of small watersheds by taking 1 ∶10 000 topographic map of Beijing Badaling Small Watershed as a data base and operating the software of Region Manager 5.0 and MATLAB 6.0 and statistic functional module of Excel.It obtains through analysis that along with the increase of DEM grid dimension and accumulated threshold value of confluence,the power function of extracted gully density is getting smaller;comparing with the factors that the influence of DEM grid dimension is greater to the precision of gully-valley extraction.It also finds out that it is better to take the average value of accumulated matrix of confluence as a basis while selecting the accumulated threshold value of confluence.
出处
《中国水土保持》
北大核心
2007年第2期56-59,共4页
Soil and Water Conservation in China
基金
北京林业大学振兴计划人才培养专项课题之空间采样与DEM精度研究
