Abstract: In order to investigate the influence of soil configuration on soil water migration characteristics in red soil slope farmland, the one-dimensional vertical water infiltration test was used to study soil water infiltration characteristics under different soil configurations and straw mulching measures. The results showed that for binary heterogeneous soil, with the increase of soil bulk density in the cultivated soil layer, the advance velocity of the wetting front and water infiltration rate slowed down, resulting in a decrease in filtration capacity. The wetting front movement's time of the simulated no-tillage measure was the longest, which was 64 min and 127 min longer than that of the 25 cm and 35 cm soil column respectively, and the cumulative infiltration amount and infiltration rate of water per unit time were the lowest. The soil water infiltration rate decreased by 5% to 23% after straw mulching, which increased the retention time of soil water and further increased the cumulative water infiltration amount. When a heterogeneous soil column was generalized into a homogeneous soil model, it showed that if the soil bulk density of the underlying soil layer was constant while the bulk density of the upper soil layer increased, the equivalent saturated water conductivity of the generalized homogeneous soil layer decreased. Additionally, as the thickness of the upper soil layer increased, the equivalent saturated water conductivity also increased.

Key words: red soil slope farmland, soil configuration, soil water, migration characteristics, cultivation, soil column simulation