新疆伊犁察南灌区土壤盐分特征

以察南灌区土壤为研究对象,对不同含盐量土壤进行盐化程度分级,并对该地区土壤盐分特征进行相关分析和主成分分析,以及对土壤盐分因子区域影响因素进行探讨。结果表明:察南灌区以碱性土壤为主,HCO_3~–是影响该灌区土壤p H最强的因子;对灌区0~100 cm土体土壤的分析表明,灌区盐化土面积约为总灌溉面积的1/4,盐渍化风险较大;相关性分析显示,HCO–3、Cl~–、SO_4~(2-)、Ca~(2~+)、Mg~(2~+)、Na~+、K~+为盐分主要组成离子,总盐分与各离子之间均呈正相关关系,与总盐分相关性最强的阴离子为SO_4~(2-),相关性最强的阳离子为Mg~(2~+);主成分分析显示,HCO_3~–、Cl~–、K~+为影响该灌区土壤盐分特征的主导因子;通过盐分因子区域影响因素定性分析可知,除HCO_3~–和pH是由河流以及地下水综合作用影响外,其他盐分因子均主要受河流影响。

Characteristics of Soil Salinity in Chanan Irrigation Area, Ili of Xinjiang

Chanan Irrigation Area in Ili of Xinjiang was selected as the study region, the soils were graded according to the salinization level, the characteristics of soil salts were analyzed by using correlation analysis and principal component analysis, and the regional influential factors on soil salinity were also qualitatively determined. The results show and that soils in the Chanan Irrigation Area are mainly alkaline, the influence of HCO₃^- on soil pH is most. Salinization soil constitutes of about 25% of the total Irrigation Area, indicating the study area is facing great risk of salinization. Correlation analysis showsed HCO₃^- , Cl^-, SO₄^2-, Ca²⁺, Mg²⁺, Na⁺ and K⁺ are the main ions of soil salt, all ions have positive correlation with total salt content, among of which, SO₄^2- and Mg²⁺ are the most correlated anion and cation respectively. The result of PCA disclosed that HCO₃^- , Cl^-and K⁺ are the dominant influential factors on soil salinity characteristics in Chanan Irrigation Area. The qualitative analysis of the regional influential factors suggest HCO₃^- and pH of soil in Chanan Irrigation Area are comprehensively influenced by river and groundwater, while other salt ions are mainly affected by rivers.