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土壤水分特征函数空间异质性是定量研究土壤非饱和带水分运动以及溶质运移的先决条件.以坡面机械布点采样、压力膜仪测定土壤水分特征曲线,并以Van-Genuchten模型拟合曲线后,用传统的统计方法与地统计方法,分析了密云水库流域周边人工油松林坡面土壤水分特征函数空间异质性.结果表明:①不同土壤层各级压力下土壤含水量变异系数(Cv)呈中等变异性,Cv为10%-25%,土壤有效饱和度越低,变异性Cv越大,计算合理取样数目越大.②模型参数θs为中等变异,Cv为17.77%-18.12%,服从正态分布;参数α为强变异性,Cv为70.65%-120.91%;参数n为弱变异性,Cv为5.29%-7.09%.③各土壤层参数θs和α均具有空间变异结构,除20-40 cm层参数α符合指数模型外,其余层参数均符合球状模型,参数θs和α变程(A)分别约为66-69及21-69 m;参数n仅在20-40 cm土壤层显示空间变异结构,符合球状模型,变程(A)约为18m;整体上该林地土壤0-20和20-40 cm层参数多以结构性变异为主,40-60 cm层参数的块金效应渐显增大.最后采用Kriging插值方法分别对各参数进行了预测.
Soil moisture characteristics are a function of spatial heterogeneity Quantitative Study of Unsaturated prerequisites and solute transport belt. In the mechanical distribution slope samples, membrane pressure characteristic curve to measure soil moisture, and to model fitting curve Van-Genuchten after using conventional statistical methods and the statistical methods to analyze the artificial pine oil slope characteristic function of soil moisture spatial heterogeneity of the surrounding basin Miyun results show that:. ① coefficient of variation of soil moisture content levels of different soil layers under a pressure (Cv ) Showed a moderate variability with a Cv of 10% -25%, the lower the soil available saturation and the larger the variability Cv, the larger the calculated reasonable number of samples.2 The model parameter θs was moderately variant with a Cv of 17.77% -18.12% The parameter α is strongly variable and the Cv is 70.65% -120.91%. The parameter n is weak variability, and the Cv is 5.29% -7.09% .③The parameters θs and α of the soil layers have the spatial variation structure except The parameter α of 20-40 cm layer is in line with the exponential model, and the parameters of the other layers are in accordance with the spherical model. The parameters θs and α (A) are about 66-69 and 21-69 m respectively. The parameter n is only in 20-40 cm soil Layer shows the structure of spatial variation, in line with the spherical model, the range (A) is about 18m; overall Soil 0-20 and the 20-40 cm layer parameters based mostly structural variation, nugget effect 40-60 cm layer parameters fade increases. Finally Kriging interpolation method for each parameter are predicted.