黄河下游三角洲盐渍区表层土壤积盐影响因子及其强度分析

采用通径分析方法研究了黄河下游三角洲盐渍区表层土壤(0～10cm)积盐的影响因子及其强度的主次关系,结果表明:表土积盐过程受到盐源分布、盐分离子化学特征、土壤理化性质、地下水状况以及区域性气候条件的综合影响;旱季条件下研究区土壤盐渍化程度较高且盐分表聚性明显;土壤盐源分布对表土层积盐的影响强度最大,其次是盐分离子组成化学特征,表土层理化属性和地下水状况主要通过其它因素对表土层积盐产生间接影响;反映盐源分布的亚表土层(10～20cm)盐分和反映土壤盐分离子化学组成特征的钠吸附比SAR、氯硫比Cl-/SO42-是表土层积盐的主要控制因素。该研究结果为黄河三角洲地区盐渍土地的科学管理与改良利用提供参考依据。

Analysis on Factors of Salt Accumulation and Intensity in Topsoil in the Saline Region of Lower Yellow River Delta

Factors affecting salt accumulation in topsoil and their intensity were studied with the application of the path analysis method, which was performed in the saline region of Lower Yellow River Delta. Results indicated that the process of salt accumulation in topsoil was generally affected by salt source distribution, chemical properties of ionic composition, soil physico-chemical properties, groundwater status and regional climatic conditions. In dry seasons the extent of soil salinization was relatively high and the top enrichment of soil salinity was apparent across the study area. The intensity of salt source distribution to salt accumulation in topsoil was the most significant, followed by chemical properties of ionic composition, while the effect of topsoil physico-chemical properties and groundwater status on salt accumulation in topsoil was via other factors. Subsoil salinity reflecting salt source distribution, plus sodium absorption ratio (SAR) and Cl-/SO42-reflecting chemical properties of ionic composition were crucial factors of salt accumulation in topsoil. The research results can serve as a reference to the scientific management, amelioration and utilization of saline soils in the Yellow River Delta.