Research On Soil Moisture Movement Of Multi Water Storage Pit In Heterogenous Soil

In northern China,drought and soil erosion are very severe.So,it is necessary to search for a new efficient irrigation method which is suitable for water holding and drought resistance in northern China.Water storage pit irrigation is a new orchard irrigation method suitable for northern hilly region. It can not only meet the need of water saving,water holding,drought resistance, but also make the best use of local rainfall runoff and efficiently reduce soil erosion.The research on it's theory and appliance will promote the development of orchard water saving irrigation and ecosystem and project of soil and water conservation.In this paper,numerical simulation and experimental research on the soil moisture movement of water storage pit irrigation are conducted.At the same time,the technical parameter of water storage pit irrigation are discussed preliminarily.The research method and content include:1. Based on the fundamental theory of dynamics of soil moisture and the condition of water storage pit irrigation,numerical modeling of soil moisture movement of single water storage pit in heterogeneous soil is established.ADI(Alternating Direction Implicit method) and Gauess-Seidel iterative method are used to solve it.By using the simulated value of modeling,the relation of water injection volume and maximum horizental distance of moisture frontal are concluded.According to the relation ,interval of pits are derived.Then ,after analyzing the infiltration characteristic of soil moisture under the condition of interference infiltration in multi storage pit,numerical modeling of soil moisture movement of multi water storage pit in heterogeneous soil is established,and its numerical solution is also acquired.2. By using the experimental device of soil moisture movement of single water storage pit and suction gauge,irrigation experiment of single water storage pit are conducted. The experimental device of soil moisture movement of multi water storage pit is developed,which can measure the infiltration of moisture and the movement of moisture frontal directly.Distribution of soil water content in all soil section are measured with y ray apparatus.3. It showed that the simulated value are in accordance with the experimental value by contrast of them.It indicates that the numerical modeling can reflect the status of soil moisture movement under the condition of water storage pit irrigation,and its method of solution is feasible.The study in this paper will provide some reference for design of technical factors of water storage pit irrigation,the conclusion will be of important value for the further study on water storage pit irrigation.