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土壤通用流失方程 (USLE)已被广泛应用于大尺度的土壤侵蚀预测 .在以往的土壤侵蚀研究中 ,由于只能获得静态的植被图 ,土壤通用流失方程只能用于土壤侵蚀的静态估算 .空间直观景观模型能在大尺度上模拟植被动态 ,为土壤通用流失方程提供动态的植被因子 ,从而使土壤侵蚀的动态模拟成为可能 .本研究结合空间直观景观模型LANDIS和土壤通用流失修正方程 ,以大兴安岭呼中林区为研究区 ,动态地模拟未来 6 5 0年内有采伐和无采伐预案下的土壤侵蚀量 ;同时以无火无采伐预案下的土壤侵蚀为对比值 .结果表明 ,土壤侵蚀量随时间变化呈周期性的波动 ,其波动程度在无火无采伐预案下最小 ,而在有火无采伐预案下最大 ;采伐对土壤侵蚀的影响没有火对土壤侵蚀的影响在空间上表现得明显 ,但是其累积效果则比火的影响强 ;降低采伐所产生的裸露土能有效降低年平均土壤侵蚀量 ,但是对土壤侵蚀动态变化的影响不明显 ;虽然采伐增加使平均土壤侵蚀量增加 ,但是也同时使土壤侵蚀的年际变化更趋于平稳 .
The generalized soil loss equation (USLE) has been widely used in large-scale soil erosion prediction. In previous studies of soil erosion, only the static vegetation map can be obtained, and the general soil loss equation can only be used for the static estimation of soil erosion. The spatial landscape model can simulate the vegetation dynamics on a large scale and provide dynamic vegetation factors for the general soil loss equation, thus making it possible to simulate the dynamic process of soil erosion.In this study, the spatial landscape model LANDIS and the universal soil loss correction equation The Huzhong forest area of Daxing’anling was used as the study area to dynamically simulate the amount of soil erosion with and without harvesting in the next 650 years and the soil erosion under the no-fire and no-cut plan as the comparative value.The results showed that the amount of soil erosion The variation with time is cyclical, the fluctuation degree is the smallest under the non-fire and non-cutting plan and the largest under the fire and non-cutting plan. The effect of harvesting on soil erosion The effect of no fire on soil erosion is obvious in space , But its cumulative effect is stronger than the impact of fire; reduce the bare soil produced by logging can effectively reduce the year They are soil erosion, but the impact on the dynamics of soil erosion is not obvious; despite logging increases the average amount of soil erosion increase, but also the annual variation of soil erosion tends to be more stable.