Laboratory of Water, Energy and Environment, National School of Engineers of Sfax, University of Sfax, B.P. 1173, Sfax 3083, Tunisia.
Department of Industrial Engineering, College of Engineering, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia.
Int J Environ Res Public Health. 2021 Dec 23;19(1):155. doi: 10.3390/ijerph19010155.
Groundwater (GW) studies have been conducted worldwide with regard to several pressures, including climate change, seawater intrusion, and water overexploitation. GW quality is a very important sector for several countries in the world, in particular for Tunisia. The shallow coastal aquifer of Sfax (located in Tunisia) was found to be under the combined conditions of continuous drop in GW and further deterioration of the groundwater quality (GWQ). This study was conducted to identify the processes that control GWQ mainly in relation to mineralization sources in the shallow Sfax coastal aquifer. To perform this task, 37 wells are considered. Data include 10 physico-chemical properties of groundwater analyzed in water samples: pH, EC, calcium (Ca), sodium (Na), magnesium (Mg), potassium (K), chloride (Cl), sulfate (SO), bicarbonate (HCO), and nitrate (NO), i.e., investigation was based on a database of 370 observations. Principal component analysis (PCA) and hydrochemical facies evolution (HFE) were conducted to extract the main factors affecting GW chemistry. The results obtained using the PCA model show that GWQ is mainly controlled by either natural factors (rock-water interactions) or anthropogenic ones (agricultural and domestic activities). Indeed, the GW overexploitation generated not only the GWQ degradation but also the SWI. The inverse distance weighted (IDW) method, integrated in a geographic information system (GIS), is employed to achieve spatial mapping of seawater intrusion locations. Hydrochemical facies evolution (HFE) results corroborate the seawater intrusion and its spatial distribution. Furthermore, the mixing ratio showed that Jebeniana and Chaffar-Mahares localities are characterized by high SWI hazard. This research should be done to better manage GW resources and help to develop a suitable plan for the exploitation and protection of water resources.
已针对包括气候变化、海水入侵和水资源过度开采在内的多种压力，在全球范围内开展了地下水 (GW) 研究。地下水质量是世界上许多国家非常重要的一个领域，突尼斯尤其如此。发现斯法克斯（位于突尼斯）的浅层沿海含水层处于地下水不断下降和地下水质量 (GWQ) 进一步恶化的综合条件下。本研究旨在确定控制 GWQ 的过程，主要与浅层斯法克斯沿海含水层中的矿化源有关。为了完成这项任务，考虑了 37 口井。数据包括对水样中地下水的 10 种理化性质进行分析：pH 值、电导率、钙 (Ca)、钠 (Na)、镁 (Mg)、钾 (K)、氯 (Cl)、硫酸盐 (SO)、碳酸氢盐 (HCO) 和硝酸盐 (NO)，即调查基于 370 个观测值的数据库。进行了主成分分析 (PCA) 和水化学相演化 (HFE)，以提取影响 GW 化学的主要因素。PCA 模型的结果表明，GWQ 主要受自然因素（岩石-水相互作用）或人为因素（农业和家庭活动）控制。事实上，地下水过度开采不仅导致 GWQ 退化，还导致海水入侵。反向距离加权 (IDW) 方法集成在地理信息系统 (GIS) 中，用于实现海水入侵位置的空间映射。水化学相演化 (HFE) 结果证实了海水入侵及其空间分布。此外，混合比表明，Jebeniana 和 Chaffar-Mahares 地区具有高海水入侵危害。应该进行这项研究，以更好地管理 GW 资源，并帮助制定一项适合的水资源开发和保护计划。
