The Experiment and Simulation for Water Movement of Preferential Flow in Soil

A large number of lab and field experiments have showed preferential flow is a ubiquitous phenomenon. Through analysis on the field dye experiment, precipitation and infliltration data in the Experimental Station in Zhengzhou and percolation test data in lab and field experiment, the paper analyze the characterization of preferential flow by a method of statistical analysis and discuss the form mechanism together with influencing factor in soil. The results show the field dye experiment of silt loam in Zhumadian, precipitation and infliltration data and the percolation test in the Experimental Station have showed the macropore caused by the root and wormhole greatly develops in the upper soil layer, tortuose and decreases with the depth. However, the cranny caused by dry shrinkage comparatively develops in the deep soil layer, the macropore has good connectivity, and therefore preferential flow easily occurs in silt loam than sand silt in Kaifeng.