• 地球信息科学 •

### DEM流径算法的相似性分析

1. 南京师范大学 虚拟地理环境教育部重点实验室, 南京 210046
• 收稿日期:2008-01-18 修回日期:2008-07-09 出版日期:2008-11-25 发布日期:2008-11-25
• 作者简介:刘学军(1965-),男,陕西合阳人,博士,教授,博士生导师。主要研究方向为DEM及其地形分析、GIS空间分析、空间数据不确定性等。Email:liuxuejun@njnu.edu.cn
• 基金资助:

国家自然科学基金资助项目(40571120),国家863计划资助项目(2006AA12Z212)

### Similarity analysis of flow route algorithms for extractingdrainage network from grid-based terrain model

LIU Xue-jun, JIN Bei, WANG Yan-fang

1. Key Laboratory of Virtual Geographic Environment, Nanjing Normal University,Ministry of Education, Nanjing 210046, China
• Received:2008-01-18 Revised:2008-07-09 Online:2008-11-25 Published:2008-11-25
• Supported by:

国家自然科学基金资助项目(40571120),国家863计划资助项目(2006AA12Z212)

Abstract:

Flow routing algorithm, which is often used to calculate the terrain parameters such as catchment area, specific catchment area, topographic wetness index and so on, is a key point in distributed hydrologic models, soil erosion modeling and other geoscience fields. The results obtained by the flow routing algorithms have distinct effects on hydrological and soil erosion modeling process. So evaluating flow routing algorithms has become a focus in these fields. In this paper, five flow routing algorithms, which are known as D8 (Deterministic eight-node), Rho8(Random eight-node ), Dinf(D-infinite), MFD ( Multiple flow direction algorithm), and DEMON ( Digital Elevation Model Networks), are selected to compare and analyze quantitatively on two Digital Elevation Model (DEM ) with 5m, 10m and 25m horizontal resolution respectively. Coefficient of relative difference, cumulative frequency distributions and XY scatter plot of the Total Catchment Area (TCA) are designed to evaluate the similarities within the selected flow path algorithms. Also the effect of DEM resolution on TCA, obtained from the selected five algorithms, is fully discussed. The results of the paper are summarized as follows: 1) differences between catchment area values estimated by the selected five flow routing algorithms were the greatest along side slopes area, and the differences decreased where the terrain became more convergent or along the channel; 2) the difference exists in any DEM with various resolutions, but is more sensitive to the high resolution DEM; and 3) multiple flow direction (MFD) algorithm is more suitable to estimate catchment area in complex terrain area than single flow direction (SFD) algorithm does that. So if the condition permits or accurate results are needed, high resolution DEM and fine MFD should be used effectively. This study also points out that the choice of flow routing algorithm has potentially important consequences for the calculation of upslope contributing areas, sediment transport capacity, topographic wetness, and several other topographic indices.