降雨因素对土壤表面结皮发育的影响

Impact of rainfall factors on soil-surface seal formation

为研究降雨因素在土壤表面结皮发育过程中的作用,结合物理模型实验方法和基于物理概念的水文响应数值模拟,以土壤表面的饱和水力传导系数Ks值作为评价指标,研究分析了雨强和累积降雨量两个降雨因素对结皮发育程度的影响。结果显示:Ks值随累积降雨量的增加而减小,且在累积降雨量较小时,Ks的减小速度更快,约为后期速度的23倍;最终累积降雨量近似的情况下,雨强较大时Ks更容易达到一稳定值;在降雨过程中,雨强与Ks的关系前后不一致。研究结果表明:降雨过程中结皮发育是个复杂的动态变化过程。

Various rainfall factors affect soil-surface seal formation.Laboratory experiments and physics-based hydrological model simulations were used to investigate the impact of rainfall intensity and cumulative rainfall depth in terms of the saturated surface hydraulic conductivity,Ks.The results show that Ks decreases as the rainfall depth increases,with the rates of decline much higher when for small rainfall depths.With similar rainfall depths,Ks is more likely to reach a stable value for higher rainfall intensities,although the relationship between Ks and the rainfall intensity value is inconsistent.The study indicates that seal formation during rainfall is a complex dynamic process.