Enhanced water use efficiency (WUE) is the key to sustainable agriculture in arid regions. The installation of capillary barriers (CB) has been suggested as one of the potential solutions. CB effects are observed between two soil layers with distinctly different soil hydraulic properties. A CB helps retain water in the upper, relatively fine-textured soil layer, suppressing water losses by deep drainage. However, retaining water in a shallow surface layer also intensifies water loss by evaporation. The use of subsurface drip irrigation (SDI) with a CB may prevent such water loss. This study evaluated the performance of SDI in a soil profile with a CB using a pot experiment and numerical analysis with the HYDRUS (2D/3D) software package. The ring-shaped emitter was selected for the SDI system for its low capital expenditures (CapEx) and maintenance. Strawberry was selected as a model plant. The results indicated that the proposed SDI system with a CB was effective in terms of WUE. The numerical analysis revealed that the CB’s depth influences the system’s water balance more than the ring-shaped emitter’s installation depth. While the CB’s shallow installation led to more root water uptake by the strawberry and less water loss by deep drainage, it induced more water loss by evaporation.

中文翻译：

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带有毛细屏障的土壤剖面中地下滴灌设计的评估

提高水资源利用效率（WUE）是干旱地区实现可持续农业的关键。已建议安装毛细管屏障（CB）作为潜在的解决方案之一。在具有明显不同的土壤水力特性的两个土壤层之间观察到CB效应。CB有助于将水分保留在质地较细的上层土壤中，从而抑制深层排水造成的水分流失。但是，将水保留在浅表层中也会加剧蒸发引起的水分流失。带有CB的地下滴灌（SDI）可以防止这种水的流失。这项研究使用盆栽试验和使用HYDRUS（2D / 3D）软件包进行的数值分析，通过CB评估了土壤剖面中SDI的性能。环形发射器因其较低的资本支出（CapEx）和维护成本而被选择用于SDI系统。草莓被选为示范植物。结果表明，提出的带有CB的SDI系统在WUE方面是有效的。数值分析表明，CB的深度对系统水平衡的影响大于环形发射器的安装深度。CB的浅层安装导致草莓吸收更多的根水，而深层排水减少了水分的流失，但它却导致了蒸发引起的更多水分流失。