论文部分内容阅读
土壤参数是地表径流模型中的关键参数,对径流过程模拟有重要影响,因此有必要明确土壤参数的作用机制。论文结合SWAT(Soil and Water Assessment Tool)模型,以广泛应用的径流曲线数模型(SCS-CN)为例,对土壤参数在SCS-CN模型中的作用进行了理论推导、分析和实例研究。分析表明,土壤饱和含水量参数与田间持水量参数的比值,是影响不同土壤湿度下地表产流能力的重要因素,两者比值越大,土壤含水量对地表产流能力的调节越弱,导致基于不同土壤模拟的地表径流量随土壤湿度的波动而上下反转。以实际流域为例,发现不同土壤数据模拟地表径流间差别的显著季节性特征;阐明该差别季节性变化的内在机制,验证了理论分析结论。为深入理解产流过程、合理选择土壤数据、模型参数优化及模拟结果解释提供了参考。
Soil parameters are the key parameters of surface runoff model and have an important influence on runoff process simulation. Therefore, it is necessary to clarify the action mechanism of soil parameters. In this paper, we combine SWAT (Soil and Water Assessment Tool) model with the widely used runoff curve number model (SCS-CN) as an example to study the role of soil parameters in SCS-CN model. The analysis shows that the ratio of saturated soil moisture content parameters to field capacity parameters is an important factor affecting the surface runoff capacity under different soil moisture. The greater the ratio of the two is, the weaker the adjustment of soil moisture content to the surface flow capacity, resulting in Surface runoff based on different soil simulations fluctuated up and down with the fluctuation of soil moisture. Taking the actual watershed as an example, significant seasonal characteristics of different soil data simulating surface runoff were found. The intrinsic mechanism of the seasonal variation of the difference was clarified, and the conclusion of the theoretical analysis was verified. This study provides a reference for further understanding of the runoff process, rational selection of soil data, optimization of model parameters and interpretation of simulation results.