Mohammed Musaab A A, Szabó Norbert P, Szűcs Péter
University of Miskolc, 3515 Miskolc, Hungary.
MTA-ME Geoengineering Research Group, University of Miskolc, Egyetemváros, Hungary.
Heliyon. 2022 Oct 28;8(11):e11308. doi: 10.1016/j.heliyon.2022.e11308. eCollection 2022 Nov.
Groundwater has recently been considered one of the primary sources of water supply in Sudan. However, groundwater quality is continuously degraded due to overexploitation and long-term agricultural operations. The fossilized Cretaceous Nubian sandstone is the principal aquifer in the study area. This research aims to determine the major factors influencing groundwater quality and detect the suitability of groundwater for drinking and irrigation purposes by integrating hydrochemical and multivariate statistical methods. Hydrochemical plots such as Piper, Chadha, and Durov diagrams were applied to detect the groundwater facies and hydrochemical processes controlling the groundwater quality. They indicated Ca-Mg-HCO water type as a dominant groundwater facies followed by Na-HCO and Na-Cl types. Gibbs plots suggested that the dissolution of the minerals is the main factor influencing the water quality. The results of the Gibbs plot were further interpreted using saturation indices (SI). The SI values indicated that aragonite, calcite, and dolomite precipitated respectively in 58.33%, 75%, and 75% of groundwater samples. Multivariate statistical analyses, including Pearson's correlation analysis, hierarchical cluster analysis (HCA), and principal component analyses (PCA), were jointly employed to identify the structure of water quality data and deduce the main factors controlling groundwater quality. The statistical analysis revealed the effect of the physical and human-induced activities as the main factors influencing groundwater chemistry. These factors are rock-water interaction, agricultural practice, and organic contamination from septic tanks. Further, the suitability of groundwater for irrigation is determined using sodium adsorption ratio (SAR) and sodium percent (Na%) indices. They carefully indicated that 75% of the groundwater samples in the study area are excellent for irrigation except for some sample location where the salinity hazard is stimulated by ion exchange. This integrated approach was effective in calibrating water quality assessment methodologies. The current research concluded that the implication of a groundwater quality monitoring scheme is crucial to ensure water supply sustainability in north Bahri city.
地下水最近被视为苏丹主要的供水水源之一。然而，由于过度开采和长期农业活动，地下水质量不断恶化。白垩纪的努比亚化石砂岩是研究区域的主要含水层。本研究旨在通过整合水化学和多元统计方法，确定影响地下水质量的主要因素，并检测地下水用于饮用和灌溉的适宜性。应用了诸如派珀图、查达图和杜罗夫图等水化学图表来检测控制地下水质量的地下水相和水化学过程。结果表明，Ca-Mg-HCO水型是主要的地下水相，其次是Na-HCO和Na-Cl水型。吉布斯图表明，矿物溶解是影响水质的主要因素。利用饱和指数（SI）进一步解释了吉布斯图的结果。SI值表明，文石、方解石和白云石分别在58.33%、75%和75%的地下水样品中沉淀。联合采用多元统计分析，包括皮尔逊相关分析、层次聚类分析（HCA）和主成分分析（PCA），以识别水质数据结构并推断控制地下水质量的主要因素。统计分析表明，物理和人为活动的影响是影响地下水化学的主要因素。这些因素包括岩石-水相互作用、农业活动以及化粪池的有机污染。此外，利用钠吸附比（SAR）和钠百分比（Na%）指数确定了地下水的灌溉适宜性。结果明确表明，研究区域75%的地下水样品非常适合灌溉，不过在一些样品位置，离子交换会引发盐度危害。这种综合方法有效地校准了水质评估方法。当前研究得出结论，实施地下水质量监测方案对于确保北巴赫里市的供水可持续性至关重要。
