@article {43928,
	title = {Identifying groundwater degradation sources in a Mediterranean coastalarea experiencing significant multi-origin stresses},
	journal = {Science of the Total Environment},
	year = {2020},
	abstract = {
	Abstract



	This study investigates the multiple contamination sources of a coastal Mediterranean aquifer in northeasternAlgeria that is bordered by two rivers and neighboring densely populated areas. Hydrogeochemical and isotopicgroundwater characterization is carried out, including the analyses of major elements, water stable isotopes δ2HH2Oand δ18O-H2O, and stable isotopes of nitrate δ15N-NO3 and δ18O-NO3, and then integrated into the history ofland use over the study area. Groundwater nitrate concentrations ranging from 1.6 to 235 mg/L with a medianvalue of 69 mg/L are evidence of the degradation of groundwater quality induced by anthropogenic sources.The combined of δ15N-NO3 and δ18O-NO3 ratios showed that nitrate in groundwater is attributable to (i) the uncontrolleddevelopment of inadequate private sanitation systems over the study area, and (ii) the unsafe applicationof animal manure to fertilize crops. Very active saltwater intrusion is confirmed by severalhydrogeochemical indicators. Interestingly, the intrusion mechanism appears to be more complex than a directintrusion fromtheMediterranean Sea. During the high-water period, saltwater intrusion may also originate fromthe two rivers bordering the aquifer, via upstream migration of seawater through the river mouths. The heavierratios in δ2H-H2O and δ18O-H2O of surface water collected from the rivers suggest that water from the MediterraneanSea is mixingwithwater in the rivers.Multi-source contamination not only contributes to complex chemicalreactionswithin the aquifer, but also contributes, via the cumulative effect of the various sources, to affecting\&nbsp;large parts of the study area. The present study may serve as a warning to the effect that historical land-use practicesmay exert seriously deleterious impacts on groundwater quality and greatly limit conditions for the sustainablemanagement of Mediterranean coastal areas.

},
	url = {www.elsevier.com/locate/scitotenv},
	author = {Lamine Boumaiza a,⁎, Romain Chesnaux a, Tarek Drias b, Julien Walter a, Fr{\'e}d{\'e}ric Huneau c,d, Emilie Garel c,d, Kay Knoeller e, C}
}
