土地覆被变化的水文响应模拟研究

采用近年来快速发展的水文模型模拟的手段，应用SWAT模型模拟了长江上游梭磨河流域不同土地覆被情景下的多年降水径流关系，定量地评估了梭磨河流域的土地覆被变化对径流、蒸发和洪峰流量的影响．结果表明，随着土地覆被状况由无植被到全是有林地覆被，径流深减小，蒸发量增加，枯季径流深减小幅度明显小于雨季的减小幅度，而且雨季初期径流深减小的幅度大于雨季后期．相同的洪水重现期，流域全为有林地覆被的情景比无植被的情景洪峰流量减小31．2％．现状覆被与未来最佳覆被之间在较大洪水上的差别不大，在较小洪水上的差别稍大．

Simulation of hydrological response to land- cover changes

Hydrological modeling methodology had a quick development in recent years.In this article,a distributed hydrological model SWAT was used to simulate the rainfall-runoff relationship of the Suomo Basin under different land covers in order to evaluate the impact of land-cover changes on runoff,evapotransperation and peak flow.The results showed that if the land-cover changed from non-vegetation-cover to full-forest-cover scenarios,the runoff depth decreased,evaporation increased,while the reduced extent of runoff in dry season was less than that in rainy season,and in the first rainy season,the reduced extent of runoff was more than that in the second rainy season.With the same recurrent flood flow,the peak flow value under full-forest-cover scenario was 31.2% less than that under non-vegetation-cover scenario.The effect of land-cover between current cover and optimum cover on hydrology was small for large storm,and big for small storm events.