植被格局对侵蚀产沙影响的研究评述

土壤侵蚀是人类可持续发展的重要挑战,植被重建则是防控侵蚀产沙的有效手段。在当前水土资源日益稀缺的新形势下,优化植被布局将成为黄土高原等生态脆弱地区未来阻蚀减沙、改善环境的重要途径,有关植被格局对侵蚀产沙影响的科技需求更加急迫、意义更加重要。为此,从坡面与流域两个尺度,总结评述了侵蚀产沙研究中的植被格局表征、侵蚀产沙对植被格局的变化响应两个议题的研究进展。分析认为,目前主要存在缺乏反映侵蚀产沙过程的植被格局表征指数、较少考虑植被与地形叠置格局对侵蚀产沙的耦合影响、尚未建立侵蚀产沙对植被格局的直观响应关系等问题。为促进有关研究,今后在格局指数和耦合关系的构建中应重视植被和地形对侵蚀产沙过程的耦合影响,并选用具有良好应用精度的分布式物理成因模型,以获得反映植被格局影响的流域侵蚀产沙结果。同时,可通过采用GIS空间分析技术,设计获得更多的典型植被格局及对应情景的侵蚀产沙,以丰富基础资料,减少信息干扰。

Review of the effects of vegetation patterns on soil erosion and sediment yield

Soil erosion is one of the main challenges to sustainable development that human beings face. Vegetation reconstruction can play an important role in controlling soil erosion and reducing sediment yield. Given that soil and water resources are becoming increasingly scarce, optimizing the vegetation distribution pattern would undoubtedly be helpful in resolving such problems, as well as in environmental improvement of ecologically fragile regions such as the Loess Plateau. Hence, there is an urgent need to elucidate the effects of vegetation distribution pattern on soil erosion and sediment yield. Keeping this in mind, this study has summarized and reviewed the progress in research on both the slope and the watershed scale on the following two issues: the characterization of vegetation patterns in soil erosion and sediment yield research, and the response of soil erosion and sediment yield to the changes in vegetation patterns. The following problems were identified following the analysis: 1) vegetation pattern metrics that can characterize the effects of soil erosion and sediment yield are still lacking; 2) the coupled effects of vegetation patterns and landforms on soil erosion and sediment yield are rarely studied; and 3) the intuitive response of soil erosion and sediment yield to the vegetation pattern has not been established. In order to promote relevant research, studies on the combined effects of vegetation patterns and landforms on soil erosion and sediment yield should be emphasized in the future, and distributed physical models with high practical accuracy should be used to obtain data on soil erosion and sediment yield, which would reflect the impact of vegetation patterns. In addition, GIS spatial analysis technology should be adopted to design more typical vegetation patterns and study the corresponding soil erosion and sediment yield, which could enrich the basic information available and reduce the presence of not relevant or inaccurate information.