State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China; School of Hydraulic and Electric-Power, Heilongjiang University, Harbin, 150080, China.
State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, China.
J Environ Manage. 2024 Dec;371:123233. doi: 10.1016/j.jenvman.2024.123233. Epub 2024 Nov 6.
The decline in groundwater quality in intensive agricultural areas in recent years, driven by environmental change and intensified human activity, poses a significant threat to agricultural production and public health, requiring attention and effective management. However, distinguishing the specific impacts of various factors on groundwater quality remains challenging, which hinders the effective management and prevention of groundwater pollution. This research integrates a hydrochemical analysis with the Entropy-weighted Water Quality Index, Self-Organizing Map (SOM) approach, and Boruta algorithm to investigate groundwater chemical variations and their influencing factors in the Sanjiang Plain, an important grain-producing region in China. The findings reveal that, compared to 2012, the deep groundwater quality has improved, while the shallow groundwater quality has markedly deteriorated. This decline in shallow groundwater quality is primarily attributable to human activities and is characterized by elevated levels of chloride, sulfate, and nitrate and a shift in the groundwater hydrochemical facies from an HCO-Ca·Mg type to a mixed HCO-Ca·Mg and SO·Cl-Ca·Mg type. The SOM results suggested that land use type significantly affects shallow groundwater quality. Further analysis with the Boruta algorithm identified increased sewage and manure emissions from expanding livestock operations as well as enhanced pollutant leakage from the expansion of paddy fields as the primary contributors to the decline in shallow groundwater quality. These findings offer new insights into the mechanisms of groundwater quality changes in agriculturally intensive regions and provide a foundation for improved groundwater pollution management in the Sanjiang Plain and similar areas.
近年来，受环境变化和人类活动加剧的影响，集约化农业区地下水质下降，对农业生产和公众健康构成重大威胁，需要引起重视和有效管理。然而，区分各种因素对地下水质量的具体影响具有挑战性，这阻碍了地下水污染的有效管理和预防。本研究将水化学分析与熵权水质指数、自组织映射（SOM）方法和 Boruta 算法相结合，调查了中国重要粮食产区三江平原地下水化学变化及其影响因素。研究结果表明，与 2012 年相比，深层地下水水质有所改善，而浅层地下水水质明显恶化。浅层地下水水质下降主要归因于人类活动，其特征是氯化物、硫酸盐和硝酸盐含量升高，地下水水化学相从 HCO-Ca·Mg 型转变为混合 HCO-Ca·Mg 和 SO·Cl-Ca·Mg 型。SOM 结果表明，土地利用类型显著影响浅层地下水水质。Boruta 算法的进一步分析表明，扩大牲畜养殖导致的污水和粪便排放量增加以及水田扩张导致的污染物泄漏加剧是浅层地下水水质下降的主要原因。这些发现为深入了解集约化农业区地下水水质变化机制提供了新的见解，并为三江平原及类似地区改善地下水污染管理提供了基础。
