因动态非平衡效应（DNE）的存在，传统土壤水力特性曲线在复杂水动力或边界条件下其准确性受到质疑。为此，项目拟科学匹配粒径与孔隙流体，系统构建不同水动力与边界条件下的土体环境。在宏观层面，通过干燥与湿润过程，系统解析孔隙流体DNE效应产生及强弱与介质粒径、孔隙流体、水动力及边界、研究尺度及干燥与湿润过程本身之间的内在机制。在微观层面，采用X-CT技术，辅以中子成像方法，研究干燥和湿润过程中孔隙结构、孔隙流体形态及流体之间界面运动等微观过程，探究不同土体粒径、水动力及边界条件下流体孔隙运动微观过程与其宏观DNE效应之间响应机制。从微观和宏观层面探讨影响DNE效应产生及强弱的关键因子，建立关键因子—DNE效应强度关系，进而揭示孔隙流体DNE效应的产生机制。项目将流体孔隙运动微观过程与DNE效应宏观响应关联研究，对于揭示土体水分与物质过程中的关键因子，构建更为科学的新型水力特性关系具重要意义。

The soil hydraulic property curve is one of the most important parameters for the research on the hydraulic process and pollutant transportation in soils. However, the limits are also evident when the soil hydraulic properties measured under static flow conditions are used under complicated hydraulic dynamic and boundary conditions due to the dynamic non-equilibrium effect (DNE). In this project, goal-specific drainage-imbibition processes with different particle size media, pore fluid pairs (air-water, NAPL-water), hydraulic dynamic conditions (fluid velocity and its change rate, and capillary number), boundary changes (change type of the boundary pressure and its change rate) are produced. At the macro level, the occurrence and strength of DNE connected to the particle size, hydraulic dynamic condition, boundary pressure change, spatial and temporal scale of the sampling, and the drainage-imbibition cycle itself are systematically investigated and characterized. At the micro level, observations of the pore structure, the shapes of the pore fluids and their interface movement via X-ray Computed Tomography and neutron imaging techniques are further performed for revealing the relationship between the occurrence and strength of DNE and the micro pore process of the pore fluids. Then the key determiners which determine the occurrence and strength of DNE are analyzed thoroughly, and the generation mechanism of DNE are put forward at a macro-micro conjunction level. The relationships between the key determiners and the DNE strengths are established under complicated soil-water systems. The project combines the micro pore processes of pore fluids and the macro responses of DNE characterizations, which will be meaningful for a further understanding of the hydraulic process and the establishment of more accurate hydraulic property curve models.