新疆克里雅绿洲土壤盐分、pH和盐基离子空间异质性分析

摘要

以克里雅绿洲盐渍化土壤为研究对象,以野外调查与实地数据为基础,采用空间自相关分析与径向基函数插值法,定量分析了克里雅绿洲土壤的含盐量、pH及盐基离子的空间异质特征.结果表明:绿洲盐渍土表聚性强、呈碱性,土壤含盐量从南至北呈现逐渐增大趋势.土壤含盐量、Na+、Ca2+、K+、Mg2+、Cl-、SO2-4均属于强空间变异,HCO-3属于中等强度的空间变异,而pH属极弱变异.土壤盐分含量、pH和盐基离子的Moran's I指数均通过了显著性检验,研究区土壤含盐量、pH与盐基离子在空间上呈现低聚集性.Pearson相关性分析结果显示,土壤盐分含量与Na+、K+、Cl-和SO2-4含量具有强正相关性(P<0.01),与Ca2+和Mg2+含量中等程度正相关(P<0.05);土壤pH与土壤含盐量及盐基离子含量极弱相关.该研究结果可为绿洲水资源合理开发与农业可持续发展提供科学依据,同时可作为盐渍土改良和沙漠化防治等环保工作的决策支撑.%In this paper, the spatial distribution characteristics of soil salinity, pH value and soluble salt ions in the Keriya Oasis were analyzed using spatial autocorrelation and radial basis function interpolation method. The results showed that saline soil had a strong surface aggregation and alkalinity, and soil salt content increased gradually from south to north. The variation coefficients of soil salinity, Mg2+, Na+, Ca2+, K+ , Cl-and SO2- 4showed high variance, HCO- 3 showed medium variance, and pH showed low variance. The Moran's I for soil salinity, pH and base cations were lower than 0.4, indicating these variables were low spatially clustered and autocorrelated. Strong positive correlations were observed between soil salinity and Na+, K+, Cl-, SO2- 4 (P<0.01), indicating that saline soils are mainly composed of chlorate and sulphate. There was moderate positive correlation between soil salinity and Ca2+ and Mg2+ contents (P<0.05). Soil pH had very weak correlations with soil salinity and soluble ions. The above results provide scientific basis for the rational exploitation of water resources and the sustainable development of oasis agriculture, and are helpful to the decision support for the improvement of saline soils and the prevention and control of desertification.