基于分形理论的土壤优先流运动控制方程

为表征土壤优先流的快速非平衡运动、更准确地预测非饱和带土壤中的水流运动和溶质运移过程，该文在活动流场模型基本理论和土壤优先流表现出的分形特征的基础上，将分形理论引入到连续性模型，根据质量守恒原理建立了描述土壤优先流形式下水流运动和溶质运移过程的控制方程，发展和完善了活动流场模型理论；对比分析了活动流场模型理论与二域模型理论和活动裂隙模型理论之间的联系和区别。研究成果为运用活动流场模型解决优先流条件下土壤水流运动和溶质运移等相关问题提供了参考。

Governing equations for modeling preferential flow in unsaturated soil based on fractal theory

To characterize the quick and non-equilibrium movement of preferential flow, and to represent the flow and transport in the unsaturated soil-water system more accurately, fractal theory was incorporated into the continuum approach based on the fundamental theories of active region model (ARM) and the fractal properties of the preferential flow patterns which were observed widely in lab and field studies. The governing equations for controlling preferential soil water flow and solute transport were derived from the mass conservation principle in this research. Furthermore, the ARM was compared with the mobile-immobile region model (MIM) and the active fracture model (AFM) to show the differences and relationship between these approaches. This research provided theoretical directions and effective approaches for using ARM to solve the related flow and transport processes resulted from preferential flow in the unsaturated soil-water system.