摘要
为探明添加生物炭对东北草甸黑土水力学特性的影响,研究了以5种生物炭体积比(0、2%、4%、6%、8%)施入土壤后的土壤水分运动参数。采用土壤的VAN GENUCHTEN模型和MUALEM理论,推导出添加生物炭土壤的水分特征曲线、相对导水率和水分扩散率方程,并用试验校验理论推导结果。理论和试验结果表明,添加生物炭土壤的饱和度随基质吸力的变化接近无添加的土壤;当基质吸力低于2 000 cm时,添加生物炭能够大大提高土壤的含水率,当基质吸力高于8 000 cm时,土壤的含水率不一定增加;水平土柱吸渗试验表明,生物炭能够抑制土壤水分的水平扩散;数值模拟降雨后的土壤含水率与田间实测数值相比误差小于13.3%。研究可为东北黑土区农业水土保护和利用提供理论依据。
In order to study the effect of biochar on hydrodynamic parameters of northeast meadow black soil, five levels of biochar with different volume ratios （0, 2%, 4%, 6% and 8%） were added into soil. The geometric model was set up by using proportion of biochar and soil, and assumed that the soil and biochar all conformed to the VAN GENUCHTEN model, and the equation of soil water characteristic curve was deduced. And by the theory of MUALEM, the relative hydraulic conductivity equation and water diffusivity equation of soil were deduced. Compared experimental results with theoretical analysis results of soil water characteristic curve, it was showed that the porosity increased in soil was not caused by the pores of biochar, it was caused by biochar and surrounding soil aggregate or the gap produced by itself. Biochar was packaged by soil aggregate, made the saturation changed with matrix suction, was close to the saturation of soil without added. When the matrix suction was lower than 2000cm, biochar can greatly improve the water content of soil, but when the matrix suction was higher than 8000cm, biochar can reduce the water content of soil. Because the biochar packaged by surrounding soil aggregate, the theory model was modified according to the experimental results, and the relative hydraulic conductivity equation and water diffusivity equation were deduced. Soil water diffusivity experiment showed that the water diffusivity equation can accurately describe the hydraulic properties of soil that added biochar, and biochar can decrease the soil water diffusion. Finally, the equations of soil water characteristic and relative hydraulic conductivity were used, and the problem of rainfall infiltration was numerically calculated. The relative error of numerically simulated soil water content afetr rainfall with the results of field experiments was less than 13.3%. It was showed that the hydraulic properties of soil that added biochar can fit the equations of the deduced theoretical model. The research results of the soil hydrodynamic parameters of soil can provide the basis of agricultural soil and water conservation and utilization for the northeast black earth area.
作者
王睿垠
魏永霞
刘慧
张翼鹏
马德才
李冠奇
WANG Ruiyin;WEI Yongxia;LIU Hui;ZHANG Yipeng;MA Decai;LI Guanqi(School of Science, Northeast Agricultural University, Harbin 150030, China;School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 150030, China;Key Laboratory of High Efficiency Utilization of Agricultural Water Resources, Ministry of Agriculture, Harbin 150030, China;Sino - French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China;China Railway Southwest Research Institute Co. , Ltd. , Chengdu 611731, China)
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2018年第7期186-194,共9页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(51479033)
国家重点研发计划项目(2016YFC0400101)
农业部农业水资源高效利用重点实验室开放项目(2017009)
关键词
草甸黑土
生物炭
饱和含水率
非饱和导水率
降雨入渗
有限元分析
meadow black soil
biochar
saturated water content
unsaturated hydraulic conductivity
rainfall infiltration
finite element analysis
