农田土壤水分和电导率空间变异性及确定其采样数的方法

Spatial Variability of Soil Water Content and Bulk Soil Electrical Conductivity and Determination of Sampling Number in Field

应用传统统计学和地统计学方法 ,分析了 2个氮肥用量间夏玉米田间 2个 10 m× 10 m区域土壤含水量和电导率的空间变异性 ,在此基础上 ,应用普通克立格技术估算了未知点的土壤含水量和电导率 ,并确定了 2种土壤特性的合理采样数目。结果表明 ,不同的氮肥用量不但影响土壤电导率的分布规律 ,而且影响土壤含水量的分布规律 ;土壤含水量和电导率的半方差函数揭示了它们的分布具有强烈的空间自相关性 ,纯块金效应除外 ;在本试验条件下 ,应用克立格方法 ,土壤含水量和电导率采样效率比传统统计学方法提高 6～

Spatial variability of soil water content and bulk soil electrical conductivity was analyzed in the two 10m×10m area of summer maize fields for two nitrogen fertilizer treatments by the classical statistics and geostatistics. Furthermore, ordinary kriging technique was applied to estimate soil water content and bulk soil electrical conductivity of unknown sites, and determine reasonable sampling numbers of two soil properties. The results showed that the nitrogen fertilizer treatments affected the spatial distribution of bulk soil electrical conductivity and soil water content, and semivariograms of soil water content and electrical conductivity revealed strong spatial dependence, except pure nugget effects, and sampling efficiency was 6 to 8 times greater than that estimated soil water content and bulk soil electrical conductivity by the classical statistical methods in this study.