Effect On Experimental Study On Soil Column Infiltration Characteristic Of Infiltration Head

Short of water resource and worsen of water and soil environment have already became very important factors in restricting agriculture of our Country and to the extent of the whole economy of our Country's persist development. For the persistent development of agriculture is depending on the persist using of water and soil. Therefore, to carry out the skill of water saving irrigation and the development of high agriculture quantity with less water are the only ways for development of agriculture of our Country.Water storage pit irrigation is a new method, suiting irrigation of hill area, combining of solving drought problem and controlling water and soil losses. It injects fresh blood for the type of water saving irrigation, and is of great importance for the type of water saving agriculture of our Country. This passage is aiming at establishing the homogeneous soil model of one dimension at varying water head, by means of studying at indoor experimentresults, analyzing the movement rule of the soil moisture, providing important reference foundation for the study of water storage irrigation.The main study contents of this passage are as follows:1 ^ Proceeded the indoor horizontal and vertical experiment on soil column of one dimension infiltration at different water head. The basic infiltration feature is like this: along with the increasing of water head, the pushing distance of wetting front is increasing slowly; at the same water head, as the time going away, the pushing speed decreases slowly. Using the horizontal and vertical experiment infiltration data, we calculate the infiltration rate. The results show, under stable water level, the accumulate infiltration capacity and the infiltration rate are distributing as power according to time. In the range of 5~60cm water head, when infiltrating at horizon, the infiltration exponent a shows no obviously changing, almost can be seen as a constant; compared with horizontal infiltration, vertical infiltration adds the effect of gravity, the infiltration exponent a changes as wave type, and has an oppositechanging tendency with /, .2 > Established one dimension infiltration math model of homogeneous soil at varying water head and soil moisture movement. To its complex boundary, we approximately use linearity Lagrange insert function to replace the functionrelationship between the experiment results of water head and time, and use latent difference method and iterative method to solute the nonlinear deflective differential equation math model, it shows it's feasible to use this method to simulate the problem of one dimension water infiltration at different water head.3 >, Proceeded the indoor one dimension soil column horizontal and vertical experiment at varying water head. As to each horizontal and vertical infiltration process, we use different infiltration models (Philip model and Kostiakov model) to fit. Results show: Philip model not only has better physics sense, but also can more successfully describe the infiltration process of this experiment.4> Drew up the one dimension soil infiltration calculation software.