畦灌是主要的地面灌溉方式之一，在我国水资源严重短缺、灌溉水资源供需矛盾仍在加剧的背景下，如何进一步提高其灌水质量是发展节水灌溉亟待解决的重要问题。本项目针对降雨产流形成的畦田土壤水分空间不均的问题，结合室内外试验与数学模拟，研究雨型对畦田土壤水分空间变异的影响效应，揭示畦田降雨产流形成的水分空间变异机理；阐明作物耗水及土壤入渗性能对土壤水分空间变异的响应规律，构建降雨-作物耗水-畦灌的分布式水分运动模型，定量评价降雨产流对畦田灌水质量的影响；结合灌水质量优化模型，发展区域尺度畦灌技术要素的适应性调控模型，提出畦田降雨产流条件下区域尺度技术要素的调控策略。预期成果将为降雨产流复杂条件下畦灌技术要素的适应性调控，实现精准灌溉提供科学依据，对于充分利用畦田降水资源，进一步提高畦田灌水质量具有重要的理论意义和应用价值。

Border irrigation is the main way of surface irrigation. Under the background of serious water scarcity and the increasing contradiction between irrigation water supply and demand in China, how to improve border irrigation performance is an important problem in the development of efficient water-saving irrigation. This project will concentrate on the spatial variability of soil moisture in border fields during the rainfall-runoff processes. Through laboratory tests, field experiments and numerical simulations, the spatial variability of soil moisture in border fields under different rainfall-runoff conditions will be explicit, and the mechanism of soil moisture spatial variation law by rainfall-runoff in border field will be illuminated. The influence mechanism of water spatial variability on crop water consumption and infiltration characteristics in border fields will be discussed. A distributed simulation model of water movement under the processes of rainfall, crop water consumption and border irrigation will be developed to quantitatively evaluate the influence law of rainfall-runoff on border irrigation performance. On this basis, the adaptive regulation model for border irrigation technique elements at regional scales will be explored considering the irrigation performance optimization. An adaptive regulating method for regional border irrigation technique elements under rainfall-runoff in border fields will be proposed. This study will contribute to solve the problems of border irrigation technique elements regulation under the complex rainfall-runoff conditions in border fields and provide scientific basis for the realization of border irrigation precision regulation. In addition, this study will give significant theoretical foundation and application value for making full use of precipitation resources in border fields and further improving border irrigation performance.