中文摘要：

覆膜开孔影响田间非均质土壤的水分运动过程，尤其当斥水程度不同时，其运动过程更趋于复杂。在控制土表不同覆膜开孔率条件下，进行了不同斥水程度的填夹砂和砂夹填的土柱蒸发实验，测定和分析了不同条件下土壤水分蒸发量变化过程和含水率剖面。结果表明，全覆膜的累积蒸发量一时间曲线明显较低，相应的蒸发10d后土壤水分剖面也与初始水分剖面接近，对于填夹砂尤其明显。覆膜开孔率增加时，同条件下两种层状土的累积蒸发量与全覆膜相比均有明显增加，表明一旦覆膜开孔，覆膜保墒效应便明显降低。斥水程度增加时，累积蒸发量有所减小，说明斥水性的存在降低了水分运移速率。当土壤为严重斥水时，斥水性对水分运动过程的影响比覆膜开孔率的影响更明显。对于不同斥水程度的填夹砂，采用对数函数表达累积蒸发量和时间的定量关系较好，而对于不同斥水程度下的砂夹填分别采用幂函数和对数函数表达。

英文摘要：

The perforated plastic mulch affects soil water movement in the heterogeneous field. Especially when soil water repellency degrees are different, the soil water movement process tends to be more complicated. Soil column evaporation experiments were conducted for Lou soil layered by sand and sand layered by Lou soil at various hydrophobic degrees under the controlled open-hole-ratio conditions. The soil water evaporation and soil moisture profiles at different conditions were measured and analyzed. The results showed that the curves of cumulative evaporation and time for full plastic mulch were obviously low, the corresponding soil moisture profile for ten days of evaporation was closed to the initial moisture profile, and this characteristic was more suitable to Lou soil layered by sand. When the open-hole-ratio increased, the cumulative evaporation of the two types of layered soil increased obviously compared with the full plastic mulch condition, showing the decreasing of mulching effects for conserving water even at small open-hole-ratios. When the water repellency degree increased, the cumulative evaporation decreased slightly, indicating the hydrophobicity of soils slowed down the water movement speed. When soil was seriously hydrophobic, hydrophobicity affected soil water movement more than open-hole-ratios. Logarithmic functions fit well for describing cumulative evaporation and time of various hydrophobic degrees of Lou soil layered by sand, while power functions and logarithmic functions were selected for sand layered by various hydrophobic degrees of Lou soils.