摘要
通过测定和拟合土壤水分特征曲线中的主脱水线和主吸水线 ,用Mualem滞后模型计算各扫描线的比水容量和导水率 ,对蒸发条件下土壤水分再分布进行了动力学模拟。研究表明 ,考虑滞后作用有效地提高了水分再分布的模拟精度 ,充分显示了水势梯度是土壤水分迁移的动力 ,而不完全是含水量的差异 ;土壤水分含量的大小不能体现水分利用的有效性 ;滞后作用减缓了湿润锋的前进速度和表层的干燥速率 。
Based on the measured main drain curve and main wet curve of soil moisture retention characteristic, the soil water redistribution during evaporation is dynamically simulated. The Mualem's hysteresis model is applied to calculate the specific water and conductivity of scanned curves. It is found that the simulation is improved if the effect of hysteresis is considered. It means the gradient of water potential is the motive power of the water transfer in soil and the efficiency of water used by plant can not be represented solely by soil water content. The effect of hysteresis reduces the advance velocity of moisture edge and drying rate of the surface layer. The model considering the hysteresis effect can reveal the microscopic dynamic characteristics of soil water movement.
出处
《水利学报》
EI
CSCD
北大核心
2002年第7期37-41,共5页
Journal of Hydraulic Engineering
基金
中国科学院水土保持所国外杰出人才基金项目 (982 60 2 )资助
