论文部分内容阅读
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 ,考虑滞后作用数学模型更能反映土壤水分运动的动力学微观特征
By measuring and fitting the main dehydration line and the main water absorption line in the soil water characteristic curve, the Mualem hysteresis model was used to calculate the specific water capacity and hydraulic conductivity of each scanning line, and the soil moisture redistribution under the evaporation condition was simulated. The research shows that considering the hysteresis effectively improves the simulation accuracy of the redistribution of water, which fully shows that the gradient of water potential is the motive force of soil moisture migration, not the difference of water content; the soil moisture content can not reflect the validity of water use ; The lag effect slowed the forward speed of wetting front and the drying rate of the surface, and the mathematical model considering hysteresis can better reflect the dynamic micro-characteristics of soil moisture movement