Moussa A.B.,University of Sfax |
Haj Salem S.B.,University of Sfax |
Zouari K.,University of Sfax |
Marc V.,Laboratoires dHydrogeologie dAvignon |
Jlassi F.,Commissariat Regional au Developpement Agricole
Environmental Earth Sciences | Year: 2011
Detailed hydrogeochemical and isotopic data of groundwaters from the Hammamet-Nabeul unconfined aquifer are used to provide a better understanding of the natural and anthropogenic processes that control the groundwater mineralization as well as the sources of different groundwater bodies. It has been demonstrated that groundwaters, which show Na-Cl and Ca-SO4-Cl water facies, are mainly influenced by the dissolution of evaporates, the dedolomitization and the cation-exchange process; and supplementary by anthropogenic process in relation with return flow of irrigation waters. The isotopic signatures permit to classify the studied groundwaters into two different groups. Non-evaporated groundwaters that are characterized by depleted δ18O and δ2H contents highlighting the importance of modern recharge at higher altitude. Evaporated groundwaters with enriched contents reflecting the significance infiltration of return flow irrigation waters. Tritium data in the studied groundwaters lend support to the existence of pre-1950 and post-1960 recharge. Carbon-14 activities in shallow wells that provide evidence to the large contamination by organic 14C corroborate the recent origin of the groundwaters in the study area. © 2010 Springer-Verlag.
Ben Moussa A.,Institute Superieur Des Science Et Technologies Of Lenvironnement Of Borj Cedria |
Mzali H.,CNRS Georesources lab |
Zouari K.,University of Sfax |
Hezzi H.,Commissariat Regional au Developpement Agricole
Quaternary International | Year: 2014
The major ion hydrochemistry and environmental isotope composition (18O, 2H) of the Tazoghrane shallow groundwaters were investigated to identify the sources and processes that affect the groundwater composition. The Quaternary shallow aquifer of Tazoghrane represents one of the most important aquifers in the Cap Bon peninsula. Groundwater from this aquifer is classified into two water types: Ca-SO4-Cl and Na-Cl. The groundwater composition is largely controlled by the water-rock interaction, particularly the dissolution of evaporate minerals and the ion exchange process. Elevated content of nitrates indicates that agricultural activities are probably the most significant anthropogenic sources of nitrogen contamination. The stable isotopic signatures reveal two water groups. Non-evaporated waters, which are distinguished by depleted d18O and d2H contents, indicate the significant recharge by modern rainfall from Mediterranean air masses. Evaporated waters that are characterized by relatively enriched d18O and d2H contents indicate an important component of recharge by return flow of irrigation waters. © 2014 Elsevier Ltd and INQUA.
Dhaoui Z.,University of Sfax |
Zouari K.,University of Sfax |
Taupin J.-D.,IRD Montpellier |
Farouni R.,Commissariat Regional au Developpement Agricole
Environmental Earth Sciences | Year: 2016
Groundwaters of the Continental Intercalaire sandstone formations at the eastern piedmont of Dahar (southern Tunisia), where they outcrop, were analysed to study the mineralization, the water origin and the current recharge process. Hydrochemical study shows that these waters present a spatial variability of chemical facies which is linked to the lithology of the host rock. The factors contributing to the mineralization are mainly the water–rock interaction in particular the dissolution of evaporitic minerals and the cation exchange reactions. Stable isotopes show an enrichment in δ18O and δ2H contents principally for piezometric levels closest to the surface, reflecting measures found in the current rainfall subject to a semi-arid to arid context. These results are coherent with those of 14C and 3H that allow the qualitative identification of a current recharge which could probably be supplied by the recent infiltration of waters in Wadis and by the direct infiltration of meteoric water through the local sandstone outcrops of the basin. This concerns in particular the well of Salem ben Salem Dabbabi, showing a content of 1.03 TU, and its static level is controlled by the Tataouine Wadi, indicating therefore an evident sign of recent recharge. © 2016, Springer-Verlag Berlin Heidelberg.
Ogilvie A.,IRD Montpellier |
Ogilvie A.,King's College London |
Le Goulven P.,IRD Montpellier |
Leduc C.,IRD Montpellier |
And 3 more authors.
IAHS-AISH Proceedings and Reports | Year: 2013
Despite small reservoirs becoming increasingly widespread across many semi-arid regions, their cumulative influence in large catchments remains poorly understood. Part of the difficulty lies in distinguishing their effect over concurrent human and climatic processes which also affect runoff. In the Merguellil catchment, in semi-arid central Tunisia, detailed analysis of 114 events revealed a 45% decrease in the runoff coefficients of rainfall events under 40 mm occurring on similar conditions of land cover and soil humidity, following the development of reservoirs and contour benches. These are capable of reducing annual flows by 25-30%. However the major decrease in catchment runoff observed after their construction is shown to be largely related to climatic fluctuations. Annual runoff variations were weakly correlated with total rainfall, but driven by changes in the number of rainfall events over 15 mm (5-6 per year) and in their circumstances, notably rainfall intensity, crop cover and antecedent soil moisture. Copyright © 2013 IAHS Press.
Grami R.,Unite Antibioresistance et Virulence Bacteriennes |
Grami R.,University of Sousse |
Mansour W.,University of Monastir |
Mansour W.,University of Sousse |
And 5 more authors.
Eurosurveillance | Year: 2016
We report a high prevalence of MCR-1 and CTX-M-1producing Escherichia coli in three Tunisian chicken farms. Chickens were imported from France or derived from French imported chicks. The same IncHI2-type plasmid reported to carry those genes in cattle in France and in a food sample in Portugal was found in Tunisian chickens of French origin. This suggests a significant impact of food animal trade on the spread of mcr-1-mediated colistin resistance in Europe. © 2016 European Centre for Disease Prevention and Control (ECDC). All right reserved.