Numerical Stimulation & Experimental Research On Soil Movement Of Multi Water Storage Pit

Water is lifeline of human being, economical and social development. It is the foundation of the sustainable development. It is water resources using level has been a evaluation standard of the sustainable development of society or area. China is a large country of irrigated agriculture, in which the shortage of water resources is very serious. Due to the underdevelopment of economy, traditional irrigation such as border and furrow irrigation is still taken as the dominant way in farmland irrigation, which leads to the great waste of water resources. Therefore, it isnecessary to research on the way of water saving irrigation.Water storage pit irrigation is a new orchard irrigation method suitable for hilly region. It has very important meaning for the development of Chinese saving water agriculture. It can not only solve the drought problems, but also control the soil erosion. In this paper, the objectives is to establish 3-D numerical modeling of soil moisture movement in heterogeneous soil, to analyze the results of experiments and calculations and master the soil moisture movement law in order to provide the theory base for researching on storage pit irrigation.In this paper, the main results are as follows:1. To measure parameters of the soil moisture movement: The soil moisture characteristic curve was measured for calculating the water specific capacity. The diffusion coefficient was measured and according to the relationship of the water specific capacity, the diffusion coefficient and the coefficient of hydraulic conductivity to calculate the coefficient of hydraulic conductivity.2. By using the device of horizontal earth column, theinfiltration laws of soil moisture in different water head wereresearched. And then, the soil infiltration rate in different water head was conducted, which is the boundary condition to establish numerical modeling of soil moisture movement of multi water storage pit.3. The method of time-divided and Gauss-Seidel were used to solve the numerical modeling of soil moisture movement that established in this paper. The irrigation experiments of multi storage pit were conducted by using the experimental device. The distribution of water contend were measured with y ray apparatus and the movement of moisture front was observed. It showed that the simulated values are in accordance with the experimental value by contrast on them. It indicates that to research on soil moisture movement under the condition of water storage pit irrigation by using this model is feasible.4. The distribution of soil moisture of one profile was calculated by using this model. This is helpful to learn about the distribution of soil moisture and the movement of moisture frontal in all soil.