SIMULATION OF SOIL WATER MOVEMENT UNDER BIOCHAR APPLICATION BASED ON THE HYDRUS-1D IN THE BLACK SOIL REGION OF CHINA

The soil water movement under different biochar treatments of the black soil region in Northeast China was simulated by the Hydrus-1d software in this paper. The simulation errors were between -5.12% and 9.15%, within the +/- 10% range. with the increasing amount of biochar applied, the residual soil moisture content and the shape parameter were decreasing, while the saturated soil moisture content and the reciprocal of air inlet value were increasing. The difference between the saturated and residual water content was getting bigger with the increasing amount of biochar applied, which improved the available soil moisture content, a beneficial factor of crop growth With increasing the amount of biochar applied, the moisture rate in the soil profile clearly increased, soil water redistribution curve right shifted significantly, which indicated that biochar can greatly improve the water retention ability of the soil. Furthermore, the soil moisture content increased when the soil depth was more than 50 cm. The effects of biochar on soil moisture diminished rapidly.