Effect of soil depth on water movement in simulated finger flow

Finger flow can be produced in the layered soil which the structure is the “soil top and sand bottom”. In the condition of finger flow happens, the thickness of upper soils is one of the main factors to influence the development of finger flow. The experiment to simulate the finger flow in the sand layer of the bottom was conducted to research the influence of thickness of upper soils on the layered soil moisture movement. The results indicated that the period that the wetting front of finger flow region arrived in a certain depth increased with the increase of the thickness of upper soils. The stable infiltration rate decreased with the increase of the thickness of upper soils. And stable infiltration rate had linear relationship with the thickness of upper soils. Besides, the experience function model and the continuous function model used to simulate the moisture infiltration of the layer structure soil showed different strengths and weaknesses.