典型草原退化梯度上土壤水溶性盐分的变化特征

土壤水溶性盐类的定量化分析,是研究土壤盐分动态变化、确定土壤盐渍化程度以及进行盐渍土改良应用的关键环节之一。以内蒙古呼伦贝尔市新巴尔虎右旗境内典型克氏针茅草原为研究对象,选取轻、中、重三个不同放牧梯度,研究土壤中水溶性离子的变化特征。结果表明:放牧强度对Cl^-、Mg²⁺没有显著性影响,对土壤SO^2-₄、Ca²⁺、K⁺和Na⁺具有极显著的影响;随着放牧强度的增强,SO^2-₄、K⁺和Ca²⁺逐渐降低,Cl^-和Na⁺均呈先增加后降低的趋势,Mg²⁺随放牧强度的增加明显下降;在土壤盐分离子的相关性分析中,SO^2-₄与Ca²⁺、SO^2-₄与K⁺、Ca²⁺与K⁺均表现为极显著的正相关关系(P＜0.01),Cl^-与Ca²⁺、SO^2-₄、K⁺均表现为显著负相关关系(P＜0.05)。

Variation Characteristics of Soil Water-soluble Salts on Different Degraded Gradients in the Typical Steppe

Quantitative analysis of soil water soluble salt is one of the key links on the study of soil salt dynamical change, determining the degree of soil salinization and application of soil amelioration. In this study, typical Stipa krylovii steppe was the research object in Hulunbeier, and we studied the water soluble salt in different grazing gradient (Light grazing, Moderate grazing, heavy grazing). The results showed that: there was no significantly influence of grazing gradient on Cl^-,Mg²⁺, yet grazing gradient significantly impacted on SO^2-₄, Ca²⁺, K⁺ and Na⁺ of the soil; As the grazing intensity increased, SO^{2 -}₄, K ⁺ and Ca²⁺ gradually reduced, both Cl^- and Na⁺ increased first and then decreased, Mg²⁺ decreased obviously with the increase of grazing intensity; In the correlation analysis of soil soluble salts, SO^2-₄ and Ca²⁺, SO^2-₄ and K⁺, Ca²⁺ and K⁺ were very significant positive correlation (P < 0.01), Cl^- and Ca²⁺, SO^2-₄, K⁺ were characterized by significant negative correlation (P<0.05).