基于统计学方法的地下水水质评价与成因分析——以齐齐哈尔市为例

地下水是我国重要的饮用水源,分析其污染成因对于确保饮用水水质安全具有重要意义。以齐齐哈尔市为例,采用统计学方法,通过数据获取、评价指标筛选、水质评价、成因分析4个步骤进行地下水水质评价与污染成因分析。结果表明:齐齐哈尔市部分地区地下水水质极差,铁、锰是主要超标指标(GB/T 14848—2017《地下水质量标准》Ⅲ类标准),且潜水铁、锰浓度超标相较承压水更为严重;铁浓度高值区主要分布在中心城区和泰来县,最大超标达54.67倍,锰浓度高值区主要分布在中心城区、泰来县和克山县,最大超标达15.40倍;地下水铁、锰浓度超标主要与原生地质条件有关,承压水铁、锰浓度超标还与该区地下水开采强度较大有关,铁浓度超标主要与地下水pH、有机质和氨氮浓度相关,锰浓度超标主要与地下水pH、溶解性离子浓度相关。

Groundwater quality evaluation and causes analysis based on statistical methods: taking Qiqihar City as an example

As an important drinking water source in China, the causes analysis of groundwater pollution is of great significance for ensuring the safety of drinking water quality. Taking Qiqihar City as an example, statistical methods were used to analyze groundwater quality and pollution causes through four steps: data acquisition, evaluation index screening, water quality evaluation and cause analysis. The following conclusions were drawn: the groundwater quality in some parts of Qiqihar City was very poor, mainly due to excessive concentration of iron and manganese (Class Ⅲ water quality of the Quality Standard of Underground Water (GB/T 14848-2017)), and the phenomenon of excessive iron and manganese of the submersible water were more serious than that of the confined water. The high value area of iron concentration was mainly distributed in the central city and Tailai County, with the maximum exceeding the standard by 54.67 times. The high value area of manganese concentration was mainly distributed in the central city, Tailai County and Keshan County, with the maximum exceeding the standard by 15.40 times. The concentration of iron and manganese exceeding the standard was mainly related to the original geological conditions, and iron and manganese in the confined water was also related to the high mining intensity of groundwater in the area. The excessive concentration of iron in the groundwater was mainly correlated to pH, organic matter and ammonia nitrogen concentration, while the concentration of manganese was mainly correlated to pH of the groundwater and the dissolved ions concentration.