沿海地区地下水中的酸盐来源和转化过程经历了各种环境压力因素
Lamine Boumaiza1, Safouan Ben Ammar2, Romain Chesnaux3
1University of Waterloo, Department of Earth and Environmental Sciences, Waterloo, Ontario, N2T 0A4, Canada.
Journal of environmental management
|August 23, 2023
概括
沿海地下水中的酸盐污染是复杂的. 这项研究使用同位素标记物和贝叶斯模型来识别肥料作为主要酸盐来源,并揭示脱和化过程. 了解这些动态对于管理地下水资源至关重要.
科学领域:
- 环境科学 环境科学
- 水文地质学 水文地质学
- 地质化学 地质化学
背景情况:
- 沿海地下水系统面临来自多个来源的复杂酸盐 (NO3) 污染.
- 在这些环境中,区分NO3来源和转化过程是具有挑战性的.
- 有效的实地研究对于了解沿海地下水中NO3污染动态至关重要.
研究的目的:
- 确定地中海沿海农业区的主要NO3来源及其贡献.
- 描述潜在的NO3转化过程 (脱化,化).
- 改善对NO3污染动态的理解,以实现可持续的地下水管理.
主要方法:
- 使用多种同位素标记物: δ18OH2O, δ2H2O, δ15NNO3, δ18ONO3和 δ11B.
- 采用贝叶斯同位素混合SIAR模型来量化NO3来源的贡献.
- 分析了突尼斯一个典型的地中海沿海农业地区的地下水样本.
主要成果:
- 地下水NO3度超过了自然水平,表明人为影响.
- 同位素特征表明,肥料,土壤有机物和污水是潜在的NO3来源.
- 混合SIAR模型证实肥料是主要的NO3来源,得到 δ11B值的支持.
- 观察到脱和化的证据,分布异质.
结论:
- 主要来自有机肥料和牲畜的便是研究区域NO3污染的主要驱动因素.
- 同时发生脱和化,反映了沿海水层中复杂的水地化学相互作用.
- 多同位素标记剂方法有效地识别了沿海环境中的多个NO3来源和过程,有助于地下水管理.
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