黄河湿地小白河片区微地形土壤盐基离子分布特征

Distribution Characteristics of Soil Base Ions in Micro Topography in Xiao Bai River Area of the Yellow River Wetland

摘要: 为探究微地形特征下不同盐基离子对不同深度土壤盐分空间分布规律，本研究以黄河小白河段滨河地区为研究区，分析不同土壤深度各盐基离子(Ca²⁺、Mg²⁺、K⁺、Na⁺、NO₃^-、F^-、Cl^-、SO₄^2-)及全盐量空间变异特征，结果表明：1) 土壤中离子总含量浓度大小关系排序为：SO₄^2- > Ca²⁺ > Cl^- > F^- > Na⁺ > NO₃^- > Mg²⁺ > K⁺。研究地土壤中盐碱类物质主要是氯化钙和硫酸钙，小白河流域特有的土壤盐分组成结构特征为氯化物–硫酸性土壤。2) 对比不同部位离子含量可知，Na^＋、F^-、SO₄^2- 和 Ca²⁺各离子含量均表现出样地2 > 样地3 > 样地1，Na^＋、F^-、SO₄^2- 和 Ca²⁺主要聚集于盆地坡面中央；对比和浓度可知其浓度呈现样地1 > 样地2 > 样地3，Cl^- 和 NO₃^- 主要聚集于海拔较低的盆地中央。3) 不同深度的土壤层离子浓度，除表面离子总含量极少之外，各层盐基离子含量均高于1500 mg/L，整体呈现出中间土层含量较高，20~30 cm之间离子总浓度值最高，两侧数值对称的势态。在土壤中各种阴阳离子主要以二价不易迁移的 Ca²⁺和 SO₄^2-居多。

Abstract: In order to explore the spatial distribution law of different base ions on soil salt at different depths under micro topographic characteristics, this study takes the riverside area of Xiao Bai reach of the Yellow River as the research area, and analyzes the spatial variation characteristics of base ions (Ca²⁺、Mg²⁺、K⁺、Na⁺、NO₃^-、F^-、Cl^-、SO₄^2-) and total salt at different soil depths. The results show that: 1) The order of the total ion concentration of soil species is SO₄^2- > Ca²⁺ > Cl^- > F^- > Na⁺ > NO₃^- > Mg²⁺ > K⁺. The saline alkali substances in the soil of the study area are mainly calcium chloride and calcium sulfate. The unique soil salt composition and structure of Xiao Bai River basin is chloride sulfate soil. 2) Comparing the ion contents in different parts, it can be seen that the ion contents of Na^＋、F^-、SO₄^2- and Ca²⁺ show that sample 2 > sample 3 > sample 1, and Na^＋、F^-、SO₄^2- and Ca²⁺ are mainly concentrated in the center of the slope of the basin; Comparing the concentrations of and it is shown that the concentrations of and are sample 1 > sample 2 > sample 3. Cl^- and NO₃^- are mainly concentrated in the center of the basin with low altitude. 3) Comparing the ion concentration of soil layers at different depths, except that the total content of surface ions is very small, the content of base ions in each layer is higher than 1500 mg/L, which shows that the content of middle soil layer is high, the total ion concentration value between 20~30 cm is the highest, and the values on both sides are symmetrical. In the soil, the divalent Ca²⁺ and SO₄^2- which are not easy to migrate are the main cations.