Hydrogeochemical processes and multivariate analysis for groundwater quality in the arid Maadher region of Hodna,northern Algeria

This study focused on water quality and hydrogeochemical processes(evolution,origin)in the Maadher region,central Hodna in Algeria.In recent decades,the excessive exploitation of this resource due to urbanization,irrigation,and the effect of climate change reaching the countries of northern Africa have caused a decline in water levels and hydrochemical changes in the aquifer.The sampling campaign in 2019 based on 13 physicochemical parameters was carried out on the water from 32 boreholes in the study area,compared to data archives of both sampling campaigns in 1967 and 1996.The result revealed that the groundwater as a whole has moderate freshwater quality,due to its total dissolved solids(TDS)content and other dissolved ions of concern(nitrate NO),which exceed WHO standards.In addition,Piper diagram indicates that the hydrochemical facies of sulfate–chloride–nitrate–calcium(SO–Cl–NO–Catype),which globally characterizes the study area and these elements are the dominant dissolved ions.Principal component analysis and hierarchical cluster analysis(HCA)methodologies are applied in order to define the major control factors that affect the hydrochemistry of Maadher plain.Three distinct water groups were found,illustrating a different evolution of salinity(EC and TDS).The HCA indicated an interesting cluster with a distinct contamination signature and most likely with significantly higher sulfate,chloride,and nitrate concentrations.Anthropogenic processes also play an important role in the study area.The water resource comes from Bousaada Wadi,the exchange at the aquifer depth and the agricultural practices contribute to the deterioration of the quality.

Evaluation of hydro-chemistry in a phreatic aquifer in the Vindhyan Region, India, using entropy weighted approach and geochemical modelling

Groundwater quality monitoring and geochemical characterization in the phreatic aquifer are critical for ensuring universal and equitable access to clean,reliable,and inexpensive drinking water for all.This research was intended to investigate the hydrogeochemical attributes and mechanisms regulating the chemistry of groundwater as well as to assess spatial variation in groundwater quality in Satna district,India.To accomplish this,the groundwater data comprising 13 physio-chemical parameters from thirty-eight phreatic aquifer locations were analysed for May 2020 by combining entropy-weighted water quality index(EWQI),multivariate statistics,geochemical modelling,and geographical information system.The findings revealed that the groundwater is fresh and slightly alkaline.Hardness was a significant concern as 57.89% of samples were beyond the permissible limit of the World Health Organisation.The dominance of ions were in the order of Ca^(2+)> Na^(+)> Mg^(2+)> K^(+) and HCO_(3)^(-)> SO_(4)^(2-)> Cl^-> NO_(3)^(-)> F^(-).Higher concentration of these ions is mainly concentrated in the northeast and eastern regions.Pearson correlation analysis and principal component analysis(PCA) demonstrated that both natural and human factors regulate groundwater chemistry in the region.The analysis of Q-mode agglomerative hierarchical clustering highlighted three significant water clusters.Ca-HCO_3 was the most prevalent hydro-chemical facies in all three clusters.Geochemical modelling through various conventional plots indicated that groundwater chemistry in the research region is influenced by the dissolution of calcite/dolomite,reverse ion exchange,and by silicate and halite weathering.EWQI data of the study area disclosed that 73.69% of the samples were appropriate for drinking.Due to high salinity,Magnesium(Mg^(2+)),Nitrate(NO_(3)^(-)),and Bicarbonate(HCO_(3)^(-)) concentrations,the north-central and north-eastern regions are particularly susceptible.The findings of the study may be accomplished by policymakers and groundwater managers to achieve sustainable groundwater development at the regional scale.

Major and Trace Element Characterization of Shallow Groundwater in Coastal Alluvium of Chidambaram Town, Cuddalore District, South India

Hydrogeochemical investigation of groundwater of Chidambaram town has been carried out to assess the suitability for drinking uses and the source for the ions acquisition process. Geologically, the area comes under the alluvial zone and is followed by tertiary formation, includes sands, sand stone, laterite, clayey black and stiff clay. The water level varies from 6 m to 10 m bgl. Twenty groundwater samples are collected and analysed for pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), major cations Ca2+, Mg2+, Na+, K+ and anions , Cl-, . The trace elements of Zn, Pb, Cr, Fe, Cd, Cu and Mn are determined. Study results reveal that groundwater in study area is a fresh water type. The pH, EC and TDS are noticed high and sequence of abundance of the major ions is Ca2+ > Na+ > Mg2+ > K+ and Cl- > > . The Stufzand chloride classification indicates that the groundwater is derived from precipitations and Scholler classification shown type I. Hydrochemical facies of groundwater are Ca2+ > Na+ > Cl- and saturation index shows that nearly all the water samples are under saturated with respect to carbonate (calcite, dolomite and aragonite) and sulfate (gypsum and anhydrite) minerals. Except Zn, other elements of Fe, Pb, Cr, Mn, Cu, and Cd are found high and above the permissible limit of drinking water standard. The ionic concentration present in the groundwater of the study area can be from wastes of commercial activities, domestic sewage and automobiles rather than by ionic exchange and geological formation.