摘要: 土壤水是作为作物可直接利用的水资源，也是农业水资源系统的核心，而地下水对土壤水的补给与涵养作用是保证土壤水量稳定的前提。因此，研究的土壤水与地下水运动特征及其联系对灌区水资源的有效利用和生态环境保护具有重要意义。以宝鸡峡灌区为研究区域，基于钻孔资料，采用不同频率和强度的降雨入渗作为供水条件，应用Hydrus和Modflow模型，探讨了多层黄土土壤水分运移特征及其地下水运动特征，构建了多层黄土条件下的水分入渗模型与三维地下水运动模型。结果显示：1) 各层土壤含水量稳定后，95 cm层土壤含水量最高，其次分别为10 cm、32.5 cm和67.5 cm。表明降雨入渗主要影响浅层土壤，对深层土壤水分的影响微乎其微；2) 土壤水分含量上，降水频率为25%时 > 50%时 > 为75%时，土壤水分变化量与降雨量大小成正比；3) 宝鸡峡灌区地下三层土中的地下水总体流向均为西北至东南，与地面起伏趋势一致；4) 暴雨级以下的降水对地下水运动状态的影响可忽略不计，地下水在垂向上的运动相对缓慢；5) 基于Hydrus建立的典型黄土灌区多层土壤水分运移模型能够准确反映典型黄土灌区土壤水分运移的特征。同时，Modflow在模拟黄土灌区地下水运动特征方面表现出良好的可行性。

Abstract: As a directly available water resource for crops, soil water is the core of agricultural water resources system, and the replenishment and conservation effect of groundwater on soil water is the premise to ensure the stability of soil water quantity. Therefore, the study of the movement characteristics and the connection is of great significance for the effective utilization of water resources and ecological environment protection in irrigated areas. In the research area, based on drilling data, using different frequencies and intensities of rainfall infiltration as water supply conditions and using the Hydrus-Modflow model, this paper discusses the multilayer loess soil water migration characteristics and groundwater movement characteristics, constructing the water infiltration model and three-dimensional groundwater movement model. The results show that: 1) After the soil water content stabilized at different layers, the highest water content was observed at the 95 cm depth, followed by 10 cm, 32.5 cm, and 67.5 cm, respectively. This indicates that rainfall infiltration primarily affects the shallow soil layers, with minimal impact on the water content of deeper soil layers; 2) On the soil moisture content, the precipitation frequency of 25% > 50% > 75%, the change amount of soil moisture is directly proportional to the rainfall amount; 3) The overall flow of groundwater in the three layers of soil in Baoji Gorge Irrigation area is from northwest to southeast, consistent with the ground fluctuation trend; 4) The influence of the precipitation below the rainstorm level on the groundwater movement state is negligible, and the movement of groundwater in the vertical upward movement is relatively slow; 5) The determination parameter R² of the typical multilayer soil moisture transport model based on HYDRUS is greater than 0.8. This paper shows that the model can accurately reflect the characteristics of soil moisture migration in typical loess irrigated areas. Meanwhile, MODFLOW showed good feasibility in simulating the characteristics of groundwater movement in the loess irrigated area.