基于SWAT模型的拉林河流域年径流侵蚀功率空间分布

Spatial Distribution of Annual Runoff Erosion Power in the Lalin River Basin Based on the SWAT Model

摘要: 本研究从能量学视角解析了流域水力侵蚀的空间分异机制，选取径流侵蚀功率作为综合表征流域地表特征、降水状况及其引发的径流对水土流失相互作用的定量指标，以东北典型水土流失区拉林河流域为研究对象，使用SWAT模型模拟分析了该流域年径流侵蚀功率的空间分布差异规律，揭示了侵蚀功率与子流域面积大小的关系。研究表明：(1) 拉林河流域多年平均径流侵蚀功率在空间上表现出“下游高于上游，干流大于支流，西北部高于东南部”的分布格局；(2) 针对集水面积小于150 km²且位于该河中上游的小流域优先实施生态治理措施，可获得显著的水土保持成效。由此可见，拉林河流域径流侵蚀功率具有明显的空间异质性特征，并与流域集水面积呈现显著相关性，揭示这一规律对指导流域生态修复具有重要的理论价值与实践意义。

Abstract: This study investigates the spatial variability mechanisms of hydraulic erosion within a watershed from an energetic standpoint. Utilizing runoff erosive power as a comprehensive quantitative metric, the research characterizes the interplay between watershed surface features, precipitation, and the associated runoff's impact on soil and water loss. The study area is the Lalin River Basin, a representative region of soil and water loss in Northeast China. Through simulation with the SWAT model, the research analyzes the spatial distribution patterns of annual average runoff erosive power and its correlation with sub-watershed area. The findings indicate that: (1) The spatial distribution of multi-year average runoff erosive power in the Lalin River Basin follows a pattern of “higher values downstream than upstream, greater in the main channel than in tributaries, and elevated in the northwest compared to the southeast”; (2) Significant soil and water conservation outcomes can be achieved by prioritizing ecological management in sub-watersheds smaller than 150 km² situated in the river’s middle and upper reaches. Consequently, the runoff erosive power in the Lalin River Basin demonstrates distinct spatial heterogeneity and a strong correlation with the watershed’s drainage area. Identifying this pattern holds significant theoretical value and practical implications for guiding ecological restoration efforts within the watershed.