预测生物炭添加对土壤饱和水力传导度的影响OA

As a soil amendment,the effect of biochar application on soil saturated hydraulic conductivity is governed by multiple factors,such as application rate,biochar type,and soil texture,and the underlying mechanism remains poorly understood.This study combined field experiments with three-dimensional modeling to investigate the improvement effects of rice straw biochar and bamboo biochar at different addition rates(3%,6%)on the saturated hydraulic conductivity of silt loam soil in the Qujialing experimental field.Field results indicate that 3%rice straw charcoal and 6%bamboo charcoal treatments enhanced saturated hydraulic conductivity in the 0～20 cm soil layer,while 6%rice straw charcoal and 3%bamboo charcoal produced inhibitory effects.To elucidate the underlying mechanisms,a 3D pore structure model of the soil-biochar mixture was constructed using Blender software to calculate the mixture porosity.Subsequently,the Terzaghi and Chapuis models were applied to predict the soil hydraulic conductivity.Comparisons revealed that the Terzaghi model more closely approximated measured values,while the Chapuis model systematically underestimated them.Both models reproduced the experimental trends observed with rice straw charcoal treatment,confirming that moderate amounts of rice straw charcoal improve saturated hydraulic conductivity by optimizing pore connectivity.However,both models exhibited certain deviations in predicting bamboo charcoal effects,primarily due to their failure to account for internal bamboo charcoal porosity.