【摘要】 土壤侵蚀模型在空间尺度上可以划分为坡面、小流域和区域3个不同层次。在坡面尺度上,主要考虑坡面侵蚀的垂直分带性及其相互影响;小流域尺度上,不但考虑坡面侵蚀的特点,还要考虑坡面来水来沙对沟道侵蚀产沙的影响、重力侵蚀及泥沙输移情况;在区域尺度上则主要考虑小流域各自的侵蚀产沙特点及其相互影响。因侵蚀的空间尺度不同,在建立土壤侵蚀模型时,要考虑由于空间变化所引起的侵蚀因子对侵蚀产沙响应的不同。影响侵蚀产沙过程的因素在时空上具有很大的不均匀性和变异性,从而增加了不同尺度间侵蚀产沙模拟的复杂性。因此尺度转换是进行不同尺度间侵蚀产沙模拟的关键所在,该文列举了5种土壤侵蚀模型建立中可以参考的尺度转换方法。通过分析评述不同空间尺度上侵蚀产沙过程及其影响因子和国内外常用的不同尺度上的侵蚀产沙模型,特别是众多科学家在我国黄土丘陵沟壑区所做的科研工作,提出了模型建立中存在的问题,可以为以后建立土壤侵蚀产沙模型提供借鉴。更多还原

【Abstract】 According to the spatial scale, almost all of the soil erosion models can be classified as field-scale models, catchment-scale models and region-scale models. Each type of erosion model has its instinctive characteristics. As to the field scale, the analysis of the erosion process on field vertical zones and the interaction between them is very important. In addition to the analysis of soil erosion on hill slopes, effects of runoff and sediment from hill slope on erosion and sediment yield of the followed gully zone and the erosion caused by gravitation are complex and pivotal in the catchments scale. In this scale, the sediment delivery has a significant importance to the erosion modeling. Establishing region scale erosion model, the relationship and the interaction of the subordinate drainages together with the style of the runoff yield and runoff concentration should be taken into account. On different scale, the influence of the main factors on runoff and sediment yield and the composition of the main factors is not the same. The factors affecting the processes of soil erosion and sediment yield have more asymmetry and variability, enhancing sediment yield modeling complexity in different scales. So, scale transfer is the key to soil erosion and sediment yield modeling on different scales. Five kinds of methods of scale transfer in other fields listed in the end of this paper, among which maybe contend some useful ways to transfer scale in modeling soil erosion. Based on the analysis of the soil erosion process and the main factors and according to some valuable works and precious experience done by some authority researches in loess hilly-gully region, this paper has put forward some existing problems in building soil erosion models. All these will provide some useful suggestions to soil erosion modeling in the future.更多还原