title: Groundwater quality and hydrochemical properties of Al-Ula Region, Saudi Arabia.
abstract: Groundwater quality monitoring is one of the most important aspects in groundwater studies in arid environments particularly in developing countries, like Saudi Arabia, due to the fast population growth and the expansion of irrigated agriculture and industrial uses. Groundwater samples have been collected from eight locations in Al-Ula in Saudi Arabia during June 2012 and January 2013 in order to investigate the hydrochemical characteristics and the groundwater quality and to understand the sources of dissolved ions. Physicochemical parameters of groundwater such as electrical conductivity, pH, total dissolved solid, and major cations and anions were determined. Chloride was found to be the dominant anion followed by HCO(-) 3 and SO4 (2-). Groundwater of the study area is characterized by the dominance of alkaline earths (Ca(2+) + Mg(2+)) over alkali metals (Na(+) + K(+)). The analytical results show that the groundwater is generally moderately hard and slightly alkaline in nature. The binary relationships of the major ions reveal that water quality of the Al-Ula region is mainly controlled by rock weathering, evaporation, and ion exchange reactions. Piper diagram was constructed to identify hydrochemical facies, and it was found that majority of the samples belong to Ca-Cl and mixed Ca-Mg-Cl facies. Chemical indices like chloro-alkali indices, sodium adsorption ratio, percentage of sodium, residual sodium carbonate, and permeability index were calculated. Also, the results show that the chemical composition of groundwater sources of Al-Ula is strongly influenced by lithology of country rocks rather than anthropogenic activities.
authors: Biology Department, Faculty of Science and Arts Al Ula, Taibah University, Al Madinah Al Munawarh, Kingdom of Saudi Arabia.
authors: Naji
authors: N
authors: Toumi
authors: Belal H M
authors: BH
authors: Hussein
authors: Sarra
authors: S
authors: Rafrafi
authors: Neama
authors: N
authors: El Kassas
mesh_terms: D057914:Agricultural Irrigation; D002254:Carbonates; D004553:Electric Conductivity; D004784:Environmental Monitoring; D060587:Groundwater / Q000737:chemistry*; D007221:Industry; D012529:Saudi Arabia; D014874:Water Pollutants, Chemical / Q000032:analysis*; D060753:Water Quality
chemical_list: D002254:Carbonates; D014874:Water Pollutants, Chemical; C005686:sodium carbonate
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