秦王川灌区农田土壤盐分离子特征分析

引大入秦工程实施以来,秦王川灌区土壤次生盐渍化问题日益成为人们关注的焦点。对秦王川灌区不同时空下的农田土壤可溶性盐分离子特征进行了统计分析以及对比分析,结果表明:秦王川盆地农田土壤八大离子中,阴离子以SO42-浓度最高,CO32-浓度最低,几乎为零,阳离子以Na+浓度最高,K+浓度最低,主要盐分包括Na2SO4、CaSO4、NaHCO3和Ca(HCO3)2等;土壤中不同盐分离子之间存在着一定程度的相关性,体现了盐分的沉积学特征以及其在土壤剖面上的分化关系;土壤的盐分含量在各种因素(灌溉、蒸发、降水以及人为耕作等)影响下,是一个时刻变化的动态过程,这种动态过程可能会在某一时间点达到某种平衡,但这种平衡会被新的因素的加入而打破。

Analysis of Farmland Soil Salinity Ions in Qinwangchuan Irrigated Regions

Secondary salinization problem of soil in Qinwangchuan irrigated regions has increasingly become the focus of attention since the Yindaruqin irrigation project was completed. In this paper, statistical and comparative analyses were used to study the farmland soil ions under different time and spaces in Qinwangchuan irrigated regions. The results showed that, among the eight ions of farmland soil, the highest concentration of anion was SO42-, the lowest concentration of anion was CO32-, which reaching almost zero, and the highest concentration of cation was Na+, the lowest concentration of cation was K+. The main soil salts included sodium sulfate, calcium sulfate, sodium bicarbonate and sodium bicarbonate and so on. There were some correlation between different soil ions, which reflected sedimentology characteristics of soil salts and their differentiation relationship in different soil profiles. Under the influence of the various factors (irrigation, evaporation, precipitation, cultivation, and so on), soil salt content was a dynamic process with time, and this process would reach a balance at some point in time which could be broken up if some new factors joined in.