卤泊滩典型田块土壤盐分三维空间分布研究

为快速了解田块土壤盐分空间分布信息，指导农业生产，论文利用电磁感应技术，测定田块表观电导率（ECa），通过建立不同深度土壤盐分的电磁感应解译模型，解译田块不同深度盐分含量，进而利用空间分析技术，获取田块土壤盐分的三维空间分布。研究结果表明，不同深度土壤盐分含量与ECa具有良好相关性（r²分别为0.875、0.839、0.851、0.866、0.926、0.861），有利于实现土壤盐分的快速诊断；通过研究获取的盐分三维空间分布，信息量丰富，可以提供土体任意方向切面的盐分分布信息。精度检验结果表明，利用三维空间分布研究获得的空间预测比二维空间分布研究具有更高精度；而且利用Kriging 插值比反距离加权（IDW）获取的空间分布具有更高的预测精度。对照盐分空间分布可以发现，研究区域在盐分含量较高的区域，土壤盐分在垂直方向呈现一定的表聚趋势，这对农业生产仍有一定的制约作用，需要加强盐渍化监测，以促进土地的可持续利用。

Research on Three Dimensional Spatial Distribution of Soil Salinity in a Typical Field of Lubotan Area

To acquire the spatial distribution information of soil salinity in field scale and to guide the agricultural production, electromagnetic induction (EM) technique was introduced in this paper to measure the apparent electrical conductivity (ECa). The soil salinity in different depth was interpreted by establishing the EM interpretation model of soil salinity. And then, the three dimensional distribution of soil salinity was obtained by spatial analysis. The result indicated, there were good correlations between the soil salinity and ECa (r² were 0.875, 0.839, 0.851, 0.866, 0.926 and 0.861 in 5 cm, 15 cm, 30 cm, 50 cm, 70 cm and 90 cm depth, respectively), which could benefit quick measurement of soil salinity; the three dimensional distribution of soil salinity contained enough information, it could supply spatial distribution information in any section of the soil solid. The result of precision test indicated, the forcast precision of spatial distribution was higher with 3D research than 2D, and it was more accurate with Kriging than IDW method. Comparing the spatial distribution of soil salinity, it could be found that top accumulation of soil salinity in vertical direction appreared in the areas with higher salt content, which could restrict the agricultural production, and the salinity survey should be continued for promoting the sustainable use of the land.