田间尺度土壤入渗规律和空间变异性研究

Research on the Field-scale Soil Infiltration Law and Spatial Variability

为了探究北京市大兴区内典型土壤的入渗规律及其影响因素,采用双环法测定大兴基地36个试验点的土壤水分入渗过程,并分别利用Kostiakov、Horton和Philip模型对土壤入渗特征参数进行拟合,同时运用经典统计学和地统计学方法分析入渗模型的回归系数、计算特征参数的统计值、揭示特征参数的空间变异规律。研究结果表明Philip模型可以作为研究区域最优入渗模型,其相关系数的均值达到0.934,各入渗特征参数的概率分布均服从正态分布或对数正态分布。入渗特征参数具有中等或强烈的空间相关性,说明随机性因素对土壤的空间变异影响较小。基于Kriging插值法得到特征参数的空间分布规律,特征参数由西向东呈现一定的递增趋势。

Double-ring method is adopted to measure the soil infiltration process of 36 test points,and infiltration parameters are developed with Kostiakov,Horton and Philip model in order to investigate infiltration law and its influencing factors of Daxing District,Beijing.At the same time,regression coefficient of infiltration model,statistical values of the characteristic parameters,and spatial variability of the characteristic parameters are calculated or analyzed by using classical statistical and geo-statistics methods.Results indicate that the Philip model can be used as the optimal infiltration model in the study area,its mean value of the correlation coefficient reaches 0.934,and probability distribution of each infiltration parameter obeys the normal distribution or the lognormal distribution.Characteristic parameters have moderate or strong spatial correlation,indicating that random factors have less influence on soil spatial variability.Based on Kriging interpolation method,spatial distribution pattern of characteristic parameters is obtained,and characteristic parameters shows a certain increasing trend from west to east.