Bulk density in 0 ~ 20cm , 20 - 40cm and field capacity in 20 ~ 40cm can be simulated with pure nugget effect model , and they are not spatially correlated in sampling scope . 4 O ~加cm 、 20一40cm土壤容重和2 } 40cm田間持水量符合純塊金效應模型,說明在采樣范圍內(nèi)它們的空間相關(guān)性不存在。