区域表层土壤EC_s和pH时空变异性分布及其相关性

Analysis on Temporal and Spatial Variability and Correlation of Surface Soil EC_s and pH in a Large-scaled Irrigation Area

应用地质统计学原理与方法,在山东簸箕李灌区开展区域表层土壤盐性和碱性分布状况的研究,描述表层土壤EC_s和pH的空间与时间变化分布趋势和特征,分析二者间的相关性。研究结果表明,表层土壤EC_s和pH在周年内表现出相近的区域时间变异分布趋势和相反的区域空间分布状况。EC_s和pH在灌区上游的西南方向和下游的分布状况相对稳定,而在中游的变化却呈现出各自的时间季节性差异,表层土壤盐性的区域空间分布状况似乎影响到其碱性的空间分布趋势。EC_s和pH间存在的负相关性不仅表观上与表层土壤盐化程度有关,还受到其它诸多因子的影响。受当地季风气候影响,EC_s在夏玉米收获期内明显低于冬小麦收获期,而pH在湿润的初秋时节则高于干旱的初夏季节,表层土壤质地类型差异对土壤盐性和碱性的影响较为明显。研究成果为灌区制定合理的区域农田水土管理策略和作物种植模式提供了科学的依据。

Applying geostatistical techniques to a large-scaled area in the Bojili Irrigation District, this article presented the study results of the temporal and spatial variability of the regional surface soil salinity, EC, and alkalinity, pH. The tendency and features of these temporal and spatial distributions and changes were depicted and the correlations between EC, and pH were analyzed. The results showed that, within a hydrological cycle year, the temporal varieties of these properties indicated similar distribution features, while the spatial varieties demonstrated the nearly opposite distribution tendency. The distributions of the soil EC, and pH in different seasons were relatively stable in the upper southwest and the lower areas, but varied significantly in the middle area of this irrigation district; the distributions of the surface soil salinity likely impacted on the distribution of the soil alkalinity. The inverse correlativity between EC, and pH not only appeared being influenced by the surface soil salinity but also in fact by many other factors. As a result of the local monsoon climates, the surface soil EC, values in the summer maize harvesting were significantly lower than those in the winter wheat harvesting, while the surface soil pH values in the humid early autumn were higher than those in the early summer season. The surface soil textures showed quite significant impacts on the surface soil EC, and pH values. The results of this study provided the rationale that will be of benefit to making the soil and water management strategies and crop patterns in this region.