Experimental Study On Soil Infiltration Characteristics Under Water-controlled Partial Wetting Irrigation

The development of facility agriculture is very fast in China,which provides different kinds of anti-season vegetables and fruit for consumers,but the vast majority of people use the traditional way of irrigation,so that consume large amounts of irrigation water consumption.The adoption of advanced water-saving irrigation techniques improves water utilization rate,planting benefits and greenhouse crop's water environment,reduces pest and disease damages and enhances product quality and yield.The water-controlled partial wetting irrigation is an irrigation method with great water-saving potential presented on an existing technology basis,and it is a technology in which with the underground water infiltration irrigation method,the bottom of planting groove is partially perforated and the planting groove is placed in a water tank with certain depth so as to use soil capillarity for infiltration irrigation.The probe into the soil water movement rules and simulation under this technical condition will be of great significance to the maturation,popularization and application of this technology.This paper measures soil water movement parameters with different volume weights in greenhouse culture,tests subsurface point source infiltration and full underground infiltration,systematically analyzes influence rules of soils with different volume weights on infiltration parameters such as soil moisture characteristic curve,diffusion rate,infiltration rate,cumulative infiltration capacity,wetting front movement,and it fits the measured data by Green-Ampt and Philip two models.The results indicated that,the passage of wetting front and soil cumulative infiltration rate and infiltration rate with infiltration time are significant or significant power function relationship;we can use Green-Ampt infiltration model to describe the relationship between the cumulative infiltration and cumulative time accurately;Green-Ampt model accuracy is higher than Philip model with underground pressure point source of soil infiltration characteristics simulation.