| Seasonal drought is a terrible problem for sustainable development of agriculture in hilly area of Sichuan basin.This study aims to answer the effect of straw mulching and no-tillage on soil moisture keeping of paddy field.Using pressure membrane method,we determined the soil characteristic curve of paddy field soil under straw mulching and no-tillage in Sichuan basin,and analyzed the dynamic characteristic of soil water energy.The results showed that the relationship between soil suction and soil water content could be simulated with the power function θ=aSb.The soil equivalent pore diameter of aeration porosity of the 10～20 cm soil layer increased under straw mulching and no-tillage and the inactive porosity reduced compared with ck.The water binding capacity and storage capacity of plough layer was improved under straw mulching.The increase of soil organic matter after straw returned to paddy field improved soil capillary porosity and soil available water,and the capacity of soil drought resistance and water supplying were also enhanced under straw mulching.The capacity of soil drought resistance was different between two kinds of tillage operations,and the effect of no-tillage was better than that of tillage at intervals. |