模拟降雨条件下含砾石土壤的坡面产流和入渗特征

Characteristics of Runoff and Infiltration in Stony Soils under Simulated Rainfall Conditions

模拟降雨条件下研究了含砾石土壤的入渗过程,分析了砾石含量和坡度对土壤坡面产流时间和入渗的影响。研究结果表明：含砾石土壤的坡面产流时间与砾石含量和坡度密切相关,当坡度〉5°时,产流时间与砾石含量呈线性负相关。当坡度〈5°时,不同砾石含量的土壤入渗能力表现出明显差异;砾石含量为20%~30%时,土壤入渗相对增加;当坡度〉10°时,砾石含量对入渗能力的影响不明显。利用Kostiakov入渗经验模型可以很好地模拟含砾石土壤的降雨入渗过程,模型中的经验系数K能够反映出降雨开始1 min内坡度和砾石含量对入渗的影响。

Based on the investigation of the infiltration process in soil containing gravels under simulated rainfall, the effects of gravel content and slope gradients on runoff generation time and infiltration were analyzed. The results indicated that runoff generation time was closely related to gravel content and slope gradients. When the gradient being higher than 5°, there was a negative relationship between runoff generation time and gravel content. As for the gradient less than 5°, there existed an evident difference in infiltration capability among the soils containing different gravel contents. As gravel content in soils was between 20% - 30%, soil infiltration increased relatively. When the gradient being higher than 10°, gravel content weakly impacted on infiltration capability. The rainfall infiltration process in soil containing gravels could be well simulated by the experiential infiltration model of Kostiakov. The parameter K in the model could reflect the effects of the gradient and gravel content on infiltration over initial 1 min.