Abstract
Saudi Arabia is an arid country with very limited water resources. The absence of surface water bodies along with erratic rainfall renders groundwater as the most reliable source of potable water in arid and semi-arid regions globally. Groundwater quality is determined by aquifer characteristics regional geology and it is extensively influenced by both natural and anthropogenic activities. In the recent past, several methodologies have been adopted to analyze the quality of groundwater and associated hydro-geochemical process i.e., multivariate statistical analysis, geochemical modelling, stable isotopes, a redox indicator, structural equation modelling. In the current study, statistical methods combined with geochemical modelling and conventional plots have been used to investigate groundwater and related geochemical processes in the Aseer region of Saudi Arabia. A total of 62 groundwater samples has been collected and analyzed in laboratory for major cations and anions. Groundwater in the study region is mostly alkaline with electrical conductivity ranging from 285–3796 μS/cm. The hydro-geochemical characteristics of groundwater are highly influenced by extreme evaporation. Climatic conditions combined with low rainfall and high temperature have resulted in a highly alkaline aquifer environment. Principal component analysis (PCA) yielded principal components explaining 79.9% of the variance in the dataset. PCA indicates ion exchange, soil mineralization, dissolution of carbonates and halite are the major processes governing the groundwater geochemistry. Groundwater in this region is oversaturated with calcite and dolomite while undersaturated with gypsum and halite which suggests dissolution of gypsum and halite as major process resulting into high chloride in groundwater. The study concludes that the combined approach of a multivariate statistical technique, conventional plots and geochemical modelling is effective in determining the factors controlling the groundwater quality.
Highlights
The absence of surface water bodies renders groundwater as most reliable source of potable water in arid and semi-arid regions globally [1]
The current study evaluates the groundwater and related geo-chemical processes using conventional graphical methods and statistical analysis in the Aseer region of Saudi Arabia
We found a high concentration of the ions that contribute to the hardness of the groundwater, i.e., 104–1658 mg/L, with an average value of 387.3 mg/L
Summary
The absence of surface water bodies renders groundwater as most reliable source of potable water in arid and semi-arid regions globally [1]. High evaporation and low precipitation ensure fewer surface water bodies resulting in a higher dependency on groundwater. In Saudi Arabia, owing to rainfall variability and scarce surface waterbodies, demand for the desalination of seawater and to some extent. Water 2018, 10, 1847 dependency on groundwater resource in Aseer province has increased tremendously in past few years. The groundwater in Saudi Arabia is found in eight large sedimentary basins. The groundwater reserves have been estimated at 1919 × 109 m3 of which 160 × 109 m3 is stored in deeper aquifers [2]. Groundwater is a significant hidden resource in context of quality and quantity. Once contaminated it is not easy to restore the aquifer and this escalates the pollution impact [3,4,5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
