针对目前黄淮海平原盐渍土改良区存在的土壤盐渍障碍问题,以该区域典型县域禹城市为研究对象,综合运用GIS和非参数地质统计学的指示克立格法,对县级和镇级两个采样尺度下0～20 cm耕层土壤盐分的空间变异性进行了分析,并给出了土壤盐分满足一定条件的概率分布图.结果表明,两个采样尺度下土壤盐分均不符合正态分布且都存在特异值,但采用指示克里格方法可以获得较为稳健的变异函数:受结构性因素与随机性因素共同影响,土壤盐分的指示半方差均表现为中等程度的空间自相关性；随着研究尺度的增加,块金值/基台值减小,变程增加,说明随着研究尺度的增加,自相关性增强,结构性因素影响增强,随机因素影响减弱；随着研究尺度的减小,盐渍化风险增大.%Taking into account the problem of soil salinization existing in the current Huanghuaihai Plain, spatial distribution of soil salinity at depth of 0 - 20 cm layer at different scales was analyzed in a typical country of Yucheng City with the application of GIS and indicator Kriging of nonparametric geostatistics, and probability maps of soil salinity were provided. The results indicated that neither soil salinity of country scale nor of town scale followed normal distribution because of the existence of outliers, but robust semivariogram could be obtained by using indicator Kriging. Soil salinity of the both scales exhibited moderate spatial autocorrelation due to compound impacts of structural and stochastic factors. The Co/Sill decreased, but range increased as the enlargement of research-scale, which indicate that the self-correlation of soil salinity increased, the influences of random factors weakened while these of structural factors increased. Salinization risk increased with the decrease of scale.
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