宿州地区农田灌溉浅层地下水水文化学特征与水质评价

Hydrochemical Characteristics and Water Quality Evaluation of Shallow Groundwater for Farmland Irrigation in Suzhou Area

摘要: 浅层地下水是宿州市周边农村农田灌溉的重要供水来源，因此，对该区域浅层地下水水化学特征以及水质分析评价具有非常重要的意义。为查明宿州地区农田灌溉浅层地下水水文地球化学与特征，本研究以皖北宿州周边农村30组农田灌溉浅层地下水为研究对象，运用描述性统计法和因子分析法对地下水的化学特征及其成因进行了分析。综合运用数理统计、Piper图、Gibbs图等方法，综合分析研究区的地下水化学特征及水岩作用，研究结果表明，宿州地区地下水中，Ca²⁺、SO₄^2-、Cl⁻、NO₃^- 含量较多，PH范围在6.7~7.4，属于中性偏弱酸性水，TDS值范围在342~745 mg/L，平均值为583.79 mg/L，属于咸水，阳离子质量浓度平均值由大到小依次为：Ca²⁺ > Na⁺ > Mg²⁺ > K⁺，阴离子质量浓度平均值由大到小依次为HCO₃^- >NO₃^- >SO₄^2- > Cl⁻ > F⁻。这些离子产生于岩盐溶解、硫酸盐岩溶解、碳酸盐岩溶解、硅酸盐岩风化等作用。综合分析，研究区所有样品符合灌溉用水条件，可以直接作为灌溉用水，不会对土壤与农作物造成危害。

Abstract: Shallow groundwater is an important source of water supply for rural farmland irrigation around Suzhou City. Therefore, it is of great significance to analyze and evaluate the hydrochemical characteristics and water quality of shallow groundwater in this area. In order to find out the hydrogeo-chemistry and characteristics of shallow groundwater for farmland irrigation in Suzhou, this study took 30 groups of shallow groundwater for farmland irrigation around Suzhou in northern Anhui as the research object, and used descriptive statistics and factor analysis to analyze the chemical characteristics and its causes are analyzed. Comprehensive use of mathematical statistics, Piper diagram, Gibbs diagram and other methods to comprehensively analyze the chemical characteristics of groundwater and water-rock interaction in the study area. The research results show that the groundwater in Suzhou area contains the most Ca²⁺、SO₄^2-、Cl− and NO₃^- . The pH range is 6.7~7.4, which belongs to neutral and weakly acidic water. The TDS value ranges from 342 to 745 mg/L, and the average value is 583.79 mg/L. It belongs to salt water. Ca²⁺ > Na⁺ > Mg²⁺ > K⁺, the average anion mass concentration from large to small is HCO₃^- >NO₃^- >SO₄^2- > Cl⁻ > F⁻. These ions are generated from the dissolution of rock salt, sulfate rock, carbonate rock, and silicate rock weathering. Comprehensive analysis shows that all samples in the study area meet the conditions of irrigation water and can be directly used as irrigation water without causing harm to soil and crops.