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Natural and artificial recharge investigation in the Zéroud Basin,Central Tunisia: impact of Sidi Saad Dam storage 总被引：1，自引：0，他引：1
Sarra Bel Hadj Salem Najiba Chkir Kamel Zouari Anne Laure Cognard-Plancq Vincent Valles Vincent Marc 《Environmental Earth Sciences》2012,66(4):1099-1110
Hydrochemical and isotopic data of waters from the Zéroud aquifer have been used to potentially provide a means for locating occurrences and to trace movements of a variety of natural and anthropogenic recharge waters in the Zéroud Basin, Central Tunisia. Geochemical data have been measured during the dam water release, from May to September 2005, with a sampling time step of 15 days. An implication of dam water has been demonstrated that is noticeable up along the main flow path to a distance of 10 km far from the injection site. Environmental isotopes 2H, 18O and 3H of water molecule were studied to investigate the effect of dam water on the hydrological system, and an isotope balance was established to compute the contribution of water storage component in groundwater. Based on isotopic mass balance, we assess that an average of 13% of total groundwater in the upper aquifer came from dam water storage. Three distinctive recharge waters in the aquifer can be determined. Water from local rainfall (pre-dam Zéroud River) that infiltrated into the boundaries of the Draa Affane Mountain was easily distinguished from the water influenced by anthropogenic recharge located in the Zéroud right rivulet. Distinguishable isotopic signatures of native wadi Zéroud recharge due to “recent lineal recharge” through the riverbed were also identified. 相似文献
2.
C. Tringali V. Re G. Siciliano N. Chkir C. Tuci K. Zouari 《Hydrogeology Journal》2017,25(5):1241-1255
Sustainable groundwater management strategies in water-scarce countries need to guide future decision-making processes pragmatically, by simultaneously considering local needs, environmental problems and economic development. The socio-hydrogeological approach named ‘Bir Al-Nas’ has been tested in the Grombalia region (Cap Bon Peninsula, Tunisia), to evaluate the effectiveness of complementing hydrogeochemical and hydrogeological investigations with the social dimension of the issue at stake (which, in this case, is the identification of groundwater pollution sources). Within this approach, the social appraisal, performed through social network analysis and public engagement of water end-users, allowed hydrogeologists to get acquainted with the institutional dimension of local groundwater management, identifying issues, potential gaps (such as weak knowledge transfer among concerned stakeholders), and the key actors likely to support the implementation of the new science-based management practices resulting from the ongoing hydrogeological investigation. Results, hence, go beyond the specific relevance for the Grombaila basin, showing the effectiveness of the proposed approach and the importance of including social assessment in any given hydrogeological research aimed at supporting local development through groundwater protection measures. 相似文献
3.
A fractionation of uranium (U) series into parent–daughter pairs – 234U and 238U – always occurs in natural waters, and the disequilibria between these is commonly used as a tracer of groundwater flow.
We report here an interpretation of the U-content and U isotope disequilibria in groundwater sampled from the deep Complexe
Terminal and Continental Intercalaire aquifers of southern Tunisia. Variations in both the contents of these isotopes (0.006–2.4 ppb)
and 234U/238U activity ratios (ARs) (1.7–15.4) were observed. The data could be plotted in two distinct fields of reciprocal U concentration
versus 234U/238U AR according to groundwater flow and regional bedrock differences. An initial assessment aimed at verifying whether the
results of this investigation support those of previous hydrogeological and isotope studies, thereby suggesting that the disequilibrium
between U isotopes in groundwater may represent a useful tool for hydrogeological investigations of deep and fossil groundwater.
In addition, the disequilibrium can be used for quantifying the recharge or mixing rates between different formations with
the aim of delineating the preferential outflow pattern or determining residence times of waters. 相似文献
4.
Tunisian Chott’s region is one of the most productive artesian basins in Tunisia. It is located in the southwestern part of
the country, and its groundwater resources are developed for water supply and irrigation. The chemical composition of the
water is strongly influenced by the interaction with the basinal sediments and by hydrologic characteristics such as the flow
pattern and time of residence. The system is composed of an upper unconfined “Plio-Quaternary” aquifer with a varying thickness
of 20–200 m, an intermediate confined/unconfined “Complex Terminal” aquifer about 100 m in thickness and a deeper “Continental
Intercalaire” aquifer about 150 m in thickness separated by thick clay and marl layers. The dissolution of evaporites and
carbonates explains part of the contained Na+, Ca2+, Mg2+, K+, SO42− and Cl-, but other processes, such carbonate precipitation, also contributes to the water composition. The stable isotope composition
of waters establishes that the deep groundwater (depleted as compared to present corresponding local rainfall) is ancient
water recharged probably during the late Pleistocene and the early Holocene periods. The relatively recent water in the Plio-Quaternary
aquifer is composed of mixed waters resulting presumably from upward leakage from the deeper groundwater. 相似文献
5.
Hydrologic and geologic factors controlling groundwater geochemistry in the Turonian aquifer (southern Tunisia) 总被引：2，自引：0，他引：2
Kamel Abid Kamel Zouari Marek Dulinski Najiba Chkir Brahim Abidi 《Hydrogeology Journal》2011,19(2):415-427
Water in the fissured limestone and dolomite of the Turonian aquifer of Tunisia has been investigated using geochemical (major ions) and isotopic (δ18O, δ2H, 14C) data. To carry out a characterization of aquifer behaviour, 48 representative samples were collected at the end of the humid season. The evolution of chemical composition of groundwater from recharge areas to discharge areas is characterized by increasing sodium, chloride and sulphate contents as a result of leaching of evaporite rock. In the study, three distinct chemical trends in groundwater were identified. The major reactions responsible for the chemical evolution of groundwater in the investigated area fall into three categories: (1) calcite precipitation, (2) gypsum and halite dissolution, and (3) ion exchange. The stable isotope composition of water samples indicates large-scale interaction between the Continental Intercalaire and the Turonian aquifer and the presence of a young local component which probably enters the system via faults and/or fractures. 相似文献
6.
Stable isotopes (??2H, ??18O and ??13C) and radiocarbon (14C) have been used in conjunction with chemical data to evaluate recharge mechanisms and groundwater residence time, and to identify inter-aquifer mixing in the Djeffara multi-aquifer in semi-arid southeastern Tunisia. The southern part of this basin, the Djeffara of Medenine aquifer system, is comprised of two main aquifers of Triassic and Miocene sandstone. The Triassic aquifer presents two compartments; the first one (west of the Medenine fault system) is unconfined with a well-defined isotope fingerprint; the second compartment is deeper and confined. Multi-tracer results show groundwater of different origins, ages and salinities, and that tectonic features control groundwater flows. Fresh and brackish groundwater from the unconfined part of the Triassic aquifer was mostly recharged during the Holocene. The recharge rates of this aquifer, inferred by 14C ages, are variable and could reach 3.5?mm/year. Brackish water of the deep confined part of the Triassic aquifer has stable isotope composition and 14C content that indicates earlier recharge during late Pleistocene cold periods. Brackish to saline water of the Miocene aquifer presents variable isotope composition. Groundwater flowing through the Medenine fault system is mainly feeding the Miocene aquifer rather than the deep confined part of the Triassic aquifer. 相似文献
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