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Purposes: This research focuses on the characterization of phosphate ore, its solid effluents, and nearby contaminated soils in the southwest Tunisia (Gafsa-Metlaoui Basin). It aims also at evaluating the vertical distribution and abundance of critical rare earth elements (REE) in the different materials and their ecological and environmental risks. Materials and methods: The sampled materials went through physical, chemical, and mineralogical characterization which involved XRF, XPS, XRD, and ICP-MS analyses. The REE anomalies and the environmental and ecological indices were calculated. Results and discussions: Results show relatively high concentrations of nine rare REEs, following the sequence La > Ce > Nd > Y > Gd > Eu > Sm > Yb > Tb and trace metal elements (TME) such as Cd, Cr, Mn, Zn, Co, Fe, Sr, Cu, Ni, Pb, Ba that surpass, in some cases, international standards. The vertical distribution of the studied elements within a sediment, tailings, and soil profiles (beyond 20 cm of depth) indicates their likely in-depth migration. TME- and REE-bearing phosphate samples reflect mostly oxic conditions in the southern area with high positive Eu anomalies signifying possible mixing of sources. The environmental assessment indicate no contamination and a moderate enrichment of REEs, except for Eu, which displays significant contamination and extreme enrichment. Whereas, a deficiency of Y has been detected in most of the studied samples except for sludge sample which was also found significantly enriched with REE. Conclusions: There are fundamental similarities between the different studied samples with high carbonate mineral concentrations. Statistical analysis confirmed the spectroscopic fingerprints demonstrating that the different materials share a similar composition. All of these similarities are most likely linked to the impact of mining activities on sediments and soils. Overall, our findings highlight the global effect of ore processing in determining the geochemical and the mineralogical characteristics of the surrounding environments of mines. [ABSTRACT FROM AUTHOR]

This study investigates the influence of geographical location on the distribution of terrestrial isopods in nine oases in the south of Tunisia. The oases were categorized as coastal, mountain, and Saharan. Quadrat sampling was conducted with five replicates in each oasis between summer 2020 and spring 2022 to determine species richness, mean densities, dominance, and diversity indices. Physico-chemical parameters, such as temperature, humidity, pHKcl, organic matter, and conductivity, were measured. Three families of isopods were collected, with Porcellionidae being the dominant family. The study found that air humidity and organic matter influenced the distribution of some species, while altitude, temperature, and pHKcl influenced others. Species richness weakly correlated with the area of the oases, and regional species richness followed an east-west gradient, with coastal oases having the highest species richness and Saharan oases having the least. The ancient oasis of Kebili (Saharan) was the most diversified, while Kettana (littoral) was the least. The Gabes oasis (littoral) had the most balanced population compared to Richet Ennaam (Saharan oasis). The study revealed the presence of a dominant species in each oasis and found differences in species dominance among the three categories of oases. [ABSTRACT FROM AUTHOR]

The damages caused by the Mediterranean fruit fly (Medfly), Ceratitis capitata (Wied.) (Diptera: Tephritidae) were assessed on citrus host fruits namely: Thomson (Citrus sinensis (L.) Osbeck), clementine (Citrus clementica Hort. ex Tan.), mandarin (Citrus delisiosa L.), bitter orange (Citrus aurantium L.) and lemon (Citrus limon (L.) Eureka) in two regions in southern Tunisia (Gabes and Tozeur) during 2013-14 - 2015-16. Damage were evaluated by the determination of percentages of fruit infestation (Percentage of punctured fruits) and of fallen fruits. Results showed that C. capitata damage varied upon citrus species and sites. The infestation rates were 42. 02, 39.83, 32.5, and 3.44% in Tozeur, against 39.86, 37.18, 30.57, and 3.38% in Gabes, respectively for Thomson, clementine, mandarin, and lemon. Besides, the highest percentages of dropped fruit were obtained for Thomson navel variety (9.02 and 7.84% in Tozeur and Gabes, respectively) against the lowest percentage recorded for the lemon Eureka variety (2.89 and 2.77% in Tozeur and Gabes respectively). In addition, the highest mean number of punctures/fruit was observed for Thomson navel variety in both regions with mean values of 3.17 and 3.38 %, respectively for Gabes and Tozeur. Results highlighted the severity of C. capitata damages in southern Tunisia and the urgency to develop appropriate control strategies in the oasis fragile ecosystem.

Southern Tunisia is known to be less deformed and simpler than its neighboring Atlassic domain to the north. This area is complex and basin evolution in the Southern Chotts‐Jeffara (SCJ) basin is debated. In this paper we combined surface and subsurface data with low temperature thermochronology (LTT) to reinvestigate the tectono‐sedimentary evolution of the SCJ basin from Permian to Jurassic. We reconstruct the present‐day architecture of the SCJ basin along two regional sections. In these sections, we focused mainly on regional thickness variations and on internal reflections interpreted from seismic data. We observe three structural elements: (a) A Paleozoic culmination, oriented E‐W, capped by Mid‐Upper Triassic deposits; (b) the Tebaga of Medenine (ToM), a culmination also oriented E‐W but located ∼50 km north of the Paleozoic culmination; and (c) A Triassic culmination in the eastern part of the area, oriented NW‐SE. We note the absence of major normal faults along the sections. The LTT data we present are the first published in this area and allow to reconstruct the timing and magnitude of vertical movements. These data prove: (a) exhumation at ∼230 Ma of the Permian and Lower Triassic units associated with the onset of the ToM removing locally about 900 m of pre‐Cretaceous sediments; and (b) the development of the Triassic culmination ∼180 Ma removing 2000 m of pre‐Cretaceous sediments in the Jebel Rehach. This study demonstrates that vertical movements in the SCJ basin are controlled by long‐wavelength processes developed essentially in shortening regimes. Key Points: Two large scale cross sections accross the Southern Chotts‐Jeffara basin allowed to interpret multiscale architecture of the basinThe basin deformation is controled by the implacement of anticlines and basin related to successive shortening regimesOutcrop observations, seismic‐well interpretation and low temperature thermochronology data allow to reconstruct the evolution of the basin [ABSTRACT FROM AUTHOR]

Wind erosion is a worldwide phenomenon for which several recent studies have shown that the intensity is expected to evolve because of climate and land use changes. Identifying the areas where wind erosion is the most active and its associated drivers may help to define efficient solutions to protect the environment from this hazard. The south of Tunisia is a region highly prone to wind erosion and presents a variety of landscapes and land uses in a relatively small area. Thus, from November 2012 to June 2016, six sites were instrumented to monitor wind erosion in the most extended land uses existing in southern Tunisia. The main results are that wind erosion: (i) is nil in the oasis, (ii) is weak (<120 kg m−1 yr−1) in the olive grove even if the surface is be ploughed up to eight times a year, (iii) is moderate (~1000 kg m−1 yr−1) in the barley field, for which the sowing date is a driving parameter of wind erosion seasonality, (iv) can occur in the Chott El Jerid except when it is flooded, (v) is the most intense in rangelands on sand (~2500 kg m−1 yr−1) and on flatbeds (>3000 kg m−1 yr−1). [ABSTRACT FROM AUTHOR]

In southern Tunisia especially in Gabes region, irrigated agriculture is the major economic sector. The intensive exploitation of groundwater have been gradually rising, leading the water quality to deteriorate. To ensure sustainable development and preserve water, soil, and land cover resources, a careful estimation of the irrigation water quality, which influence on the regional agriculture activities. The objective of this study is to investigate the irrigation water suitability based on hydrogeological, hydrochemical, and analytic hierarchy approach (AHP) and water quality index (WQI). Results highlighted that TDS of the groundwater ranged from 0.4 to 6 g/L. The most abundant chemical species in the water were Ca2+, Cl−, SO42−, and Na+, with mean concentration of 460 mg/L, 1320 mg/L, 1450 mg/L, and 1200 mg/L, respectively. The largest amounts were discovered along the shoreline and in deep aquifers embedded in Cretaceous sediments. AHP has used as multicriteria decision analysis, to weighting groundwater quality criteria, and groundwater suitability for irrigation has been mapped. Based on the Quality index "WQI", the water samples are categorized into three types: excellent, acceptable, and worthless. A 45% of sampled water is not suitable for irrigation use. However, groundwater quality is increasingly poor towards the coastal areas and north of the study area. This study concluded that the method adopted in assessing the groundwater quality in arid coastal areas led to important results and could be helpful scholar to improve their research especially in similar areas. It can also assist decision makers in taking proactive solutions to protect and preserve groundwater resources from pollution risks. [ABSTRACT FROM AUTHOR]

Wind erosion is a worldwide phenomenon for which several recent studies have shown that the intensity is expected to evolve because of climate and land use changes. Identifying the areas where wind erosion is the most active and its associated drivers may help to define efficient solutions to protect the environment from this hazard. The south of Tunisia is a region highly prone to wind erosion and presents a variety of landscapes and land uses in a relatively small area. Thus, from November 2012 to June 2016, six sites were instrumented to monitor wind erosion in the most extended land uses existing in southern Tunisia. The main results are that wind erosion: (i) is nil in the oasis, (ii) is weak (−1 yr−1) in the olive grove even if the surface is be ploughed up to eight times a year, (iii) is moderate (~1000 kg m−1 yr−1) in the barley field, for which the sowing date is a driving parameter of wind erosion seasonality, (iv) can occur in the Chott El Jerid except when it is flooded, (v) is the most intense in rangelands on sand (~2500 kg m−1 yr−1) and on flatbeds (>3000 kg m−1 yr−1).

The current study highlights the impacts of mining and ore processing activities on the environment and human health in a south Mediterranean area of southern Tunisia. A geochemical characterization was achieved by analyzing urban soil, stream sediments, mine wastes (tailings, sludge) and phosphate ore, for trace metals "TM" (Cd, Cr, Zn, Mn) have revealed that the samples are highly enriched with metals. An evaluation of the contamination status was attained by calculating pollution indices. Results showed that samples are ranging between moderately and very strongly polluted with TM. Human health risk was evaluated by calculating hazard quotient (HQ), total non-carcinogenic risk (NCR) expressed as hazard index (HI) and carcinogenic risk (CR). The non-carcinogenic risk (NCR) did not exceed the established threshold (NCR > 1) in all studied cases (age or gender based). Thus, local residents of the study area are likely far from developing non-carcinogenic diseases arising from TM exposure. Conversely, CR did exceed the proposed standards (CR > 10–4) in some cases. Accordingly, there is a carcinogenic risk associated with children's exposure to Cr. Globally, our findings prove that children of Gafsa–Metlaoui mining area are more vulnerable to TM contamination than adults could develop health complications. To a lesser extent, females are also more vulnerable than males in the concerned area. In order to eliminate any potential health risks, waste management's legislation should be established in Tunisia and similar areas worldwide (open cast-mining, abandoned mine sites, etc.) to control and mitigate the effects of mining and industrial activities on the environment and the human health. [ABSTRACT FROM AUTHOR]

In Southern Tunisia, as in the major part of agro-based countries under arid and semi-arid climate, the growing water dependent-economies, the increasing scarcity of freshwater resources amplified by the frequent dry climatic episodes and the continuous aquifer decompression define huge challenges for sustainable agricultural development. Multiple environmental issues have been observed related principally to natural resources degradation. Besides to the ecological value, the decreasing of agro-systems production has crucial social, economic and health repercussions. Thus, the present study aims the assessment of the sustainability of different natural resources in the oasis lands, the principal agro-system in southwestern Tunisia. The collected data from field investigations and farming surveys have been completed by analytical laboratory work and literature review. The obtained results indicate that groundwater resources are highly mineralized with doubtful to locally unsuitable quality to be used in irrigation according to the different calculated ionic indices (EC > 3,000 µs/cm; SAR from 6.7 to 9.5; TH between 48 and 69; PI from 46% to 58%) suggesting severe recommendations to be used especially for long term irrigation. The physico-chemical analyses of the soil samples highlight, furthermore, the progressive degradation of these agricultural lands characterized by high EC values above 3.6 and 5.8 mS/cm threatening the safe production of many crop yields. In addition to the difficult natural conditions, farming practices are the most influential factors governing the distribution of water quality related issues and soil hydrodynamic and physico-chemical proprieties. A comprehensive flexible adaptation management measures are required in the study area as the degradation issues have reached tolerance limits of different ecological systems and many irreversible alteration have been observed. These strategies should be evaluated as a shared task between the different parts relative to water consumption and agro-based activities. [ABSTRACT FROM AUTHOR]

The present study focused on the "Continental Intercalaire" (CI), the North Africa′'s hugest aquifer. It uses different disciplines: geology, hydrogeology, and geophysics for achieving enhanced characterization of the Tunisian "CI" in Mednine -Tataouine area (Southern Tunisia), marked by highly constrained surface water resources. Besides, this study represents a successful example of petroleum and water data joint use for hydrogeological purposes. Petroleum wells are better distributed and deeper than water boreholes. They give more complete information on the subsurface stratigraphy, whereas water boreholes furnish hydrochemistry, hydrodynamic, and hydrophysical data. Used geophysical data were composed of well logs and 2D seismic reflection profiles. Available well logs were gamma ray (GR), resistivity, and sonic (ΔT) logs. Their analysis allowed a precise delimitation of the "CI" reservoirs, which chiefly consist of the sandstone layers of Boulouha, Douiret, Chenini, and Oum Diab members. Lithostratigraphic correlations according to different directions were established, and sixty-eight seismic reflection sections were interpreted for the reconstitution of the "CI" geometry. They highlighted that this aquifer is absent in the Jeffara domain and characterized by notable variations in depth, thickness, and lithological composition in the Dahar domain; it shows thickening (373 m), deepening (1607 m), and enrichment in clays towards the southwest, while a thinning (100 m) towards the north and a pinchout towards the northeast. This arrangement has been mainly generated by the Lower Cretaceous synsedimentary NW–SE and E-W normal faulting and the Hercynian, intra-Triassic, and Barremian to Upper Aptian compressive manifestations. The delineated geometry has an important effect on the groundwater circulation and characteristics. By generating tilted block structure of the "CI," NW–SE normal faulting favors groundwater flow and water temperature increase towards the southwest. The present study yielded to interesting results that may contribute to a better management of groundwater resources in southern Tunisia. It can be also a reference of other scientific research dealing with the Northern Sahara Aquifer System (SASS). [ABSTRACT FROM AUTHOR]

Flonicamid is a systemic insecticide that acts as a feed blocker with potential use against whiteflies in an IPM program. The efficacy of flonicamid against populations of Bemisia tabaci in geothermal greenhouses in southern Tunisia. Flonicamid was tested in irrigation and foliar spraying on a greenhouse tomato crop. The use of the insecticide in irrigation or foliar spraying showed significant insecticidal activity on eggs, larvae and adults of B. tabaci. They are comparable to those caused by the reference insecticide confidor and different from those of the control on the different stages of development of B. tabaci. It is advisable to use flonicamid in an integrated pest management program in a heated greenhouse.

The Ghadames Basin is considered as huge intracratonic structure, which preserved over 4000 m of Paleozoic sedimentary succession deposited over the Precambrian Basement. The present work consists of an integrated interpretation of the Paleozoic interval in the Ghadames basin of southern Tunisia using well logs and calibrated seismic data. Thus, the adopted sequence stratigraphic approach allowed the identification of a total of 3 s-order sequences, bounded by Taconic, Caledonian, and Hercynian unconformities recognized as major tectonic discontinuities in the study area. The determined second-order sequences have been further subdivided into fourteen third-order sequences with their associated systems tracts, which are limited by sequence boundaries (SB), and presenting transgressive surfaces (TS), and maximum flooding surfaces (mfs). Each sequence is characterized by a unique stacking pattern and distinctive facies, thus reflecting the lithology and the corresponding depositional environment. These sequences are composed of claystone and sandstone facies deposited in varying depositional environments, ranging from a shallow marine setting during the Ordovician period to a deep marine environment during the Early Silurian. A complex deltaic environment was evidenced during the Late Silurian involving to a fluvial environment during the Devonian period. The integration of well logs and seismic data proved to be an efficient approach in the delineation of sequence stratigraphy, revealing in detail the spatial distribution and sequence organizations within the study area. These later are controlled by the relative sea level variations, with eustasy is being the dominant factor. The obtained results are mainly correlatable with the sequence stratigraphy of North African basins at a regional scale and Snedden and Lee chart (2010) at a global scale. • Three second order sequences have been found within the Research Area. • Based on Gamma-ray log shapes, fourteen third order sequences have been identified. • The obtained results are correlatable at a regional and global scales. • Depositional environments have been deduced from gamma-ray log shapes. • The obtained results are correlatable at regional and global scales. [ABSTRACT FROM AUTHOR]

We present here the typological and archaeometric/petrographic characterization of the production of the pottery workshop of Oued el Akarit, Southern Tunisia, following a new survey of the site. This workshop mainly produced during the 4th century four amphora types (Africana I B, Africana II D, Keay 25.1-2, and perhaps late variants of type Dressel 2/4), together with cooking wares (B and CB, but also imitations of categories A and AC typical of Northern Tunisia) and coarse wares. Despite the presence of abundant kiln wasters, which seem to exclude the presence of imports, the petrographic analysis showed heterogeneous fabrics, even inside each class, which could be explained with the use of different raw materials and production techniques in several workshops/kilns relatively scattered in time and/or space.

The global warming resulting from anthropogenic activities is considered a major threat for the biodiversity in arid and semi-arid regions worldwide. North African countries in western Mediterranean basin, including Tunisia, are expected to experience strong rainfall drop and temperature increase in the next few decades, interrogating the geographical distribution of many plant species in the context of future climate change. Here, ecologically based quantitative climatic envelope model was developed using Maximum Entropy (MaxEnt) to predict current and future distribution of Brassica tournefortii in Tunisia. The data inputs were composed of the species occurrence data and nineteen climatic layers varied over time in line with the predictions created from the global warming scenarios (RCP 4.5 and RCP 6.0) by 2050 and 2070. Using nine uncorrelated variables fitting very well our MaxEnt model, results revealed that the distribution of B. tournefortii was mainly influenced by precipitation-related variables, which contributed with 79.58% in the model, whereas a small contribution was attributed to temperature-related variables (18.20%). Moreover, a noticeable reduction in the current species' range was recorded, compared with that observed during Last Glacial Maximum (LGM). However, the results suggested a small increase in the areas of very highly, highly, and moderately suitable habitats for the species (0.2, 0.28, and 2.41%, respectively) by 2070 under RCP 6.0. Importantly, we found that the habitat suitability of the species, when applying a climate envelope model, was optimal both along the coastal and the dry South-Western zones of the study area. Overall, the results indicated that B. tournefortii exhibits a great tolerance to severe abiotic constraints of southern Tunisia and seemed to be able to survive under future environmental conditions of its adaptation range. These findings can be used to design reasonable exploitation strategies in order to benefit from the ecological and economical values of B. tournefortii. [ABSTRACT FROM AUTHOR]

The aim of the study was to identify the best evaporation process that allows obtaining a dry methanol extract of Moringa oleifera leaves rich on phytochemicals and showing a significant antioxidant activity. The liquid extract, prepared by the maceration of the leaves of M. oleifera into 70% aqueous methanol at room temperature, was evaporated using three solvent evaporation methods, these included evaporation in air at room temperature, with rotary evaporator and in an oven at 40 °C. Extracts were investigated for total polyphenols content (TPC), total flavonoids content (TFC), total condensed tannins content (TCTC), identification and quantification of some phenolic compounds by high-performance liquid chromatography coupled with photodiode array and mass spectrometry detection (HPLC-PDA-ESI/MS) and evaluated for antioxidant activity. The analysis of extracts by HPLC-PDA-ESI/MS showed that the dry extract obtained in dark after oven evaporation exhibited the highest amounts of 13 out of 19 phenolic compounds; quinic acid, gallic acid, 4-O-caffeoylquinic acid, caffeic acid, trans-ferulic acid, apigenin 7-O-glucoside, quercetrin, kaempferol, naringenin, apigenin, luteolin, cirsiliol and cirsilineol. In all extracts, quinic acid, 4-O-caffeoylquinic acid, rutin and quercitrin were present as the main compounds. The chemical composition and the antioxidant potential of the methanol extract are strongly affected by the method of evaporation of the solvent used. The highest values of TPC, TCTC and the antioxidant activity were provided by the extract obtained when the solvent was evaporated in oven. These results showed that the evaporation of the solvent in the oven at 40 °C was the best evaporation method to be used for the extraction of phytochemicals from the leaves of M. oleifera by cold maceration method using 70% aqueous methanol as solvent. • Highest amounts of Moringa phenolic compounds were found in oven extract at 40 °C. • LC/MS method was developed for analysis of 33 phenolic compounds in Moringa leaves. • Phenolic compounds composition was strongly affected by solvent evaporation method. • Main compounds were quinic acid, 4-O-caffeoylquinic acid, rutin and quercitrin. [ABSTRACT FROM AUTHOR]

Deltaic petroleum systems are often complex and heterogeneous. Delineation of sandstone bodies in such complex depositional settings constitutes a crucial challenge in reservoir exploration. However, reservoir characterization based on conventional well-logs and stratigraphic interpretation in complex settings often leads to uncertainties. In this work, we present an integrated quantitative interpretation to reveal heterogeneity and the reservoir properties in a complex deltaic environment. The study benefits from integrating borehole lithology logs, electrical well logging, and a 3D post-stack seismic cube. To demonstrate the practical application and effectiveness of our proposed approach, seismic inversion has been applied to the Acacus Formation in the Ghadames Basin of southern Tunisia. We estimate the acoustic impedance volume from 3D seismic data using a stochastic inversion algorithm. This algorithm enables the generation of multiple realizations, accounting for uncertainties and providing a more comprehensive understanding of subsurface impedance. Then, the porosity model is computed by establishing a functional relationship between acoustic impedance and porosity. The analysis of the relationship between acoustic impedance and different rock properties helped to differentiate lithological units of sandstone and claystone. This lithology classification is used to estimate the lithofacies model. Finally, the obtained porosity and lithofacies models are validated with well data. The crucial correlation between facies distribution and porosity allows for accurate mapping of individual thin sandstone bodies and their property distribution beyond well control. The lithofacies model shows significant sandstone bodies in the Acacus A and C units that constitute good reservoirs. The porosity model confirms this, as these sandstone facies exhibit high porosity (20%). The proposed approach has proven to be powerful in reservoir delineation, characterization, and exploration, and can be applied in similar geological setting basins, and frameworks. • Acoustic impedance volume is estimated from seismic data using a stochastic inversion algorithm. • Acoustic impedance's relationship with different rock properties is analyzed, for sandstone and claystone differentiation. • Porosity cube is obtained from a linear relationship with acoustic impedance. • Lithofacies model is derived from a lithological classification using acoustic impedance cross-plot versus VpVs ratio. • Heterogeneity and reservoir characteristics of the Acacus sandstone are revealed based on an integrated interpretation. [ABSTRACT FROM AUTHOR]

The present study relies on field work, including detailed sedimentological and sequence stratigraphic analyses of the oxic Cenomanian-Turonian carbonates in Southern Tunisia. Based on petrographic study, six microfacies were recognized (MF1-MF6). These microfacies are grouped into three facies associations referred to peritidal flat, shallow subtidal and deep subtidal environments, suggesting an inner ramp type-platform. The sequence stratigraphic analysis led to interpret these sequences as a transgressive systems tract (TST) which, locally, contains abundant microfauna of the Whiteinella archaeocretacea biozone. The TST interval is capped by a centimetric highly bioturbated limestone bed corresponding to the maximum flooding surface (MFS). The logged sections culminate with the highstand systems tract (HST) referred to the Gattar Member. Sea-level fluctuations have played a key role in shaping the sequence stratigraphic patterns and driving the associated diagenetic processes. These features were developed in meteoric, marine, mixed meteoric-marine realms including eodiagenetic and mesodiagenetic states. The impact of diagenesis on reservoir properties is twofold, with both enhancing and reducing effects. Porosity is increased by the dissolution of aragonitic rudistic shells, resulting in moldic and vuggy pores, while dolomitization creates intercrystalline porosity. Fractures improve permeability networks by creating channels for fluid movement. However, cementation, micritization and compaction gave detrimental effects on reservoir properties. The improvement of reservoir quality noted along HSTs is primarily linked to diagenetic processes associated with a drop-in sea level. In the Tataouine region, intense dolomitization occurred in the TSTs, resulting in increased porosity and a more promising reservoir potential. [Display omitted] • We describe an atypical Late Cenomanian-Early Turonian carbonates deposited in oxic conditions. • Six microfacies are originated from three depositional environments: peritidal flat, shallow subtidal and deep subtidal. • Three systems tracts are detailed: upper Zebbag Formation (HST), Bahloul equivalent (TST), and Gattar Member (HST). • The reservoir quality prediction is linked to depositional environment and diagenesis in sequence stratigraphic framework. [ABSTRACT FROM AUTHOR]

In this study, we investigated the habitat, the daily activity and the trophic niche overlap of three carnivores found in southern Tunisia, namely the fennec fox (Vulpes zerda), the red fox (Vulpes vulpes) and the African golden wolf (Canis anthus) over seasons. To achieve this goal, we surveyed 300-meter transects in Sidi Toui National Park (N=29) and in Oued Dekouk Natural Reserve (N=24) over a year. Using information provided by camera trap photos and scats analysis; we determined daily activities and diets of the three canids. African golden wolves and red foxes shared most of their habitat in the two areas, especially in Sidi Toui National Park, while fennec foxes were restricted to the sandy area in Oued Dekouk Natural Reserve. Based on 729 photos produced by camera trap, we observed that the African golden wolf had a continuous activity through the day and the year, while the red fox and the fennec fox were active also through the year but mainly during twilight. We were able to identify food items from 504 scats, which included fruits, invertebrates, rodents, lagomorphs, birds, reptiles and livestock. Our results showed a significant variation in the diets between the species, seasons and sites. Rodents and livestock represented, respectively, 11.7% and 19.2% of the biomass consumed by the African golden wolf over the year. Both foxes ate invertebrates and rodents with different frequency during the seasons. The trophic niche overlap was very high between the two foxes (O j k > 0.95) and partial between each fox species and the wolves (O j k < 0.65). The knowledge of the habitat and the trophic niche overlap of these three carnivores increases our understanding of factors responsible for their coexistence, which may help to improve management and conservation actions. [ABSTRACT FROM AUTHOR]

In 2012, Deudorix livia was responsible for severe losses in production of pomegranate trees in the regions of Gafsa and Gabes situated in Southern of Tunisia. D. livia was observed on some pods of Acacia farnesiana planted as windbreak around these orchards. Larvae of D. livia were observed drilling fruits to eat seeds. At present, the life cycle of D. livia is poorly studied. We confirmed its identification using molecular tools and reported for the first time its occurrence in Southern of Tunisia.

The spatial distribution of trace elements of strontium (Sr), barium (Ba), bromide (Br), boron (B) and lithium (Li) was investigated in the deeper confined continental Intercalair (CI) and the underlying confined/unconfined Complex Terminal (CT) aquifers in southern Tunisia. Geochemical analyses and correlation between trace and major elements suggested that dissolution/precipitation of minerals, water rock interaction are the main factors responsible for the occurrence of these elements in the two aquifers. However, in the CI Djerid aquifer, in addition to these factors, the process of basic exchange is generally responsible for the large variation in cation concentration (Ca, Na, and K) and the five trace elements of interest. The Sr2+ has been used along with Li and other hydrogeological information to trace the extent of leakage from the CI to the CT aquifer. Besides, high 87Sr/86Sr and Br/Cl recorded in the Tazrarit CI1 borehole imply that salinity may be derived from a contact with marine facies in the sediment formation. [ABSTRACT FROM AUTHOR]

This study focuses on the description of rudists observed within the Berressef Formation from the Matmata area in the Saharan platform of southern Tunisia. The study of rudists is based on two measured stratigraphic sections and five observation points. It has revealed for the first time the presence of Coniacian-Santonian rudists. Two rudist associations were identified: 1) Biradiolites angulosus-Biradiolites martellii-Radiolites trigeri association (Coniacian) containing Durania cf. arnaudi , Bournonia cf. gardonica , Biradiolites sp., Hippurites sp. and Apricardia sp.; and 2) Radiolites dario-Bournonia fascicularis association (late Coniacian-Santonian) including Sauvagesia sp. and Radiolites sp. These associations have showed a remarkable similarity with those of central-south of Apennines, Italy. Rudists of the Berressef Formation are mostly elevators in growth position. They present cylindrical to elongated cylindrical shapes and they are organized in isolated individuals, bouquets and clusters. The rudist facies A is mostly represented by rudists in growth position. The facies B consisted of bioclastic limestones rich in rudists fragments, which is considered to have been deposited not far from their original palaeoenvironment. [ABSTRACT FROM AUTHOR]

Nous présentons les résultats préliminaires d'un projet Tuniso-Italien de collaboration scientifique dans le domaine des études environnementales et de la recherche préhistorique et anthropologique en Tunisie méridionale mené selon une approche interdisciplinaire qui comprend la géo-archéologie, la géochronologie, la géochimie, la palynologie, la paléoanthropologie et la génétique. La zone de recherche se trouve au sud du Chott el Jérid et ses environs. Il s’agit d’une zone caractérisée par la présence de l’un des méga lacs qui existaient dans le Sahara pendant les périodes humides à la fin du Quaternaire. La région est une zone charnière entre la Méditerranée et le Sahara, donc favorable à l’étude des diffusions culturelles et des déplacements humains à travers les différentes périodes et environnements.

The fossil dendrobranchiate shrimp Macropenaeus was originally described from the Upper Cretaceous (Cenomanian) limestones of Hadjoula, northwest Lebanon. A new species, M. sidiaichensis sp. nov., was recovered from the Sidi Aïch Formation in the Northern Chotts Range, southern Tunisia. The Barremian occurrence of the genus in Tunisia suggests that Macropenaeus most likely originated in northern Africa and then migrated to Arabia in the Cenomanian. The association of the fossil shrimp with conchostracans, plant fragments, and fish indicates the interaction of freshwater and marine conditions that characterized the northern African margin as part of widespread coastal complex, paralic environments during the Barremian. [ABSTRACT FROM AUTHOR]

Southern Tunisia exhibited thick series of naturally occurring gypsum deposits. Those evaporites may constitute important feeds for plaster industry. An in-depth study of the evaporites deposits outcropping in the Tataouine area (southern Tunisia) has been undertaken to find out their detailed physical and chemical properties. Ten gypseous samples collected from the Oued El Ghar study site were characterized using several techniques. Thus, physical-chemical characterization concerned chemical analysis by X-ray fluorescence, mineralogical analysis by X-ray diffraction and spectroscopic analysis by Fourier transform infrared. Other techniques including thermogravimetric analysis and textural analysis were used for the assessment of the Mestaoua gypsum deposits. It was found that the studied samples were mainly composed of sulfates (as $$ {\text{SO}}_{3}^{ - } $$ ) and calcium oxide (CaO) together with minor amounts of silica, iron and magnesium oxides. This chemical composition was completed by specific surface area measurements (21.25 m/g), volumic mass (2.33 g/cm) and porosity (17.2 %). A technical specifications chart was established to gather the main requirements that will be used as criteria for the selection of products to be manufactured. Based on the above-mentioned analyses, natural gypsum deposits of the Mestaoua area showed the required technical specifications for use as feeds for the manufacture of plaster and derivatives, adjuvant, chemicals, among other industrial uses. [ABSTRACT FROM AUTHOR]

2-D seismic reflection sections, borehole data as well as published and unpublished data have been investigated to reconstruct the paleogeography of southern Tunisia during Middle to Late Permian times. Paleogeographical reconstruction based on the integration of petroleum well data and 2-D seismic facies interpretation shows three main depositional areas with very contrasting sedimentary pile. These are 1) a subsiding basin; 2) an outer shelf carbonate, and 3) an inner shelf carbonate. Based on typical electric responses of reef buildups to seismic wave, we shall urge that during Middle Permian times, the outer carbonate shelf was subject of reef barrier development. Lithology evidences from core samples show that reef framework correspond mainly to fossiliferous limestone and dolomite. The WNW-ESE recognized reef barrier led between latitudes 33° 10′ 00″N and 33° 20′ 00″N. The Tebaga of Medenine outcrop constitutes the northern-edge of this barrier. Westward it may be extended to Bir Soltane area whereas its extension eastward is still to be determined. Biogenic buildups took place preferentially over faulted Carboniferous and lower Paleozoic paleohighs resulting likely from the Hercynian orogeny. The subsiding basin is located north of Tebaga of Medenine outcrop where Upper Permian sedimentary sequence is made entirely of 4000 m deep marine green silty shale facies. These are ascribed to unorganized and chaotic reflectors. Inner carbonate shelf facies succession corresponds to a typical interbedding of shallow marine carbonate deposits, shale, dolomite, and anhydrite inducing parallel-layered of strong amplitude and good continuity reflectors. Also within the inner carbonate shelf patch reef or reef pinnacles have been identified based on their seismic signature particularly their low vertical development as compared to reef complexes. Southward, towards Sidi Toui area, the Upper Permian depositional sequence thins out and bears witness of land influences as entailed by the increase of silicoclastic sedimentary supply and the lack of marine fossil. [ABSTRACT FROM AUTHOR]

The fossil clam shrimp genus Ordosestheria was originally described from the Lower Cretaceous (Aptian) Jingchuan Formation in Inner Mongolia, northwestern China. The species taxonomically described in this paper as Ordosestheria chottsensis sp. nov. was recovered from the uppermost Bouhedma Formation in the northern Chotts range of southern Tunisia. The early Barremian occurrence of the genus in Tunisia suggests that ordosestheriids have most likely originated in North Africa and then migrated to East Asia in the Aptian. Moreover, the occurrence of fossil spinicaudatans in two horizons respectively from the Bouhedma and Sidi Aïch formations indicates the interaction of freshwater and marine conditions that characterized the northern African margin as part of widespread complex paralic environments over the Chotts and Gafsa areas during the Barremian. [ABSTRACT FROM AUTHOR]

The hydrochemical and isotopic investigation of the Nefzaoua aquifer system demonstrates that groundwater mineralization in is controlled by natural and anthropogenic processes including water-rock interaction and irrigation return flow. It identifies all of the water bodies that flow within the aquifer system and their circulation patterns. The isotopically depleted paleowaters, identified within the deep and intermediate aquifers, undergo significant enrichment by evaporation during irrigation and recharged the shallow aquifer by return flow. Subsequently, they infiltrate to the intermediate aquifer which receives also rainfall modern recharge. [ABSTRACT FROM AUTHOR]

During the last few years, several cases of West Nile virus (WNV) infection in humans have been reported in Tunisia. However, detailed information on WNV infection in wild birds, the primary amplifying host of WNV, are lacking. In this work, we investigated the exposure of wild sparrows (hybrid Passer domesticus × hispaniolensis) living in two oases in southern Tunisia (Gabès and Kébili oases) to WNV, through the detection of WNV-specific antibodies by using ELISA and microneutralization tests. In total, 208 birds were sampled (54 from Kébili, 154 from Gabès). Anti-WNV antibodies were detected in two birds, corresponding to an overall seroprevalence of 1%. There was no significant difference between the two sampled populations [1·85% (1/54) in Kébili, 0·65% (1/154) in Gabès]. These data provide indirect evidence of the exposure of resident sparrows in southern Tunisia to WNV. [ABSTRACT FROM PUBLISHER]

The fossil clam shrimp genus Cratostracus was first described from the Turonian–Coniacian (Upper Cretaceous) Qingshankou Formation in the Jilin and Heilongjiang provinces of China, and it has been found to range down into the Aptian Guantou Formation in Zhejiang Province of southeastern China. Recently, species tentatively attributable to it ( Cratostracus ? cheni ) has been recorded in the well-known Jehol Biota bearing Barremian–lower Aptian (Lower Cretaceous) Yixian Formation in western Liaoning Province of northeastern China. The species described in this paper as Cratostracus ? tunisiaensis sp. nov. was recovered from the Sidi Aïch Formation in the Chotts area of southern Tunisia. Although only tentatively attributed to Cratostracus , its occurrence is consistent with a Barremian (Early Cretaceous) age for the formation. This first direct dating of the Sidi Aïch Formation gives a valuable insight for the stratigraphy of the region and will make it possible to more precisely correlate the different outcrops of the Sidi Aïch Formation. Moreover, the new fossil discovery allows a reconstruction of the paralic ecosystem that characterized the study area during the Barremian. [ABSTRACT FROM AUTHOR]

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During these last years, considerable attention has been given to unconventional oil and gas shale in northern Africa where the most productive Paleozoic basins are located (e.g. Berkine, Illizi, Kufra, Murzuk, Tindouf, Ahnet, Oued Mya, Mouydir, etc.). In most petroleum systems, which characterize these basins, the Silurian played the main role in hydrocarbon generation with two main ‘hot’ shale levels distributed in different locations (basins) and their deposition was restricted to the Rhuddanian (Lllandovery: early Silurian) and the Ludlow–Pridoli (late Silurian). A third major hot shale level had been identified in the Frasnian (Upper Devonian). Southern Tunisia is characterized by three main Paleozoic sedimentary basins, which are from North to South, the southern Chotts, Jeffara and Berkine Basin. They are separated by a major roughly E–W trending lower Paleozoic structural high, which encompass the Mehrez-Oued Hamous uplift to the West (Algeria) and the Nefusa uplift to the East (Libya), passing by the Touggourt-Talemzane-PGA-Bou Namcha (TTPB) structure close to southern Tunisia. The forementioned major source rocks in southern Tunisia are defined by hot shales with elevated Gamma ray values often exceeding 1400 API (in Hayatt-1 well), deposited in deep water environments during short lived (c. 2 Ma) periods of anoxia. In the course of this review, thickness, distribution and maturity maps have been established for each hot shale level using data for more than 70 wells located in both Tunisia and Algeria. Mineralogical modeling was achieved using Spectral Gamma Ray data (U, Th, K), SopectroLith logs (to acquire data for Fe, Si and Ti) and Elemental Capture Spectroscopy (ECS). The latter technique provided data for quartz, pyrite, carbonate, clay and Sulfur. In addition to this, the Gamma Ray (GR), Neutron Porosity ( Φ N ), deep Resistivity ( R t ) and Bulk Density ( ρ b ) logs were used to model bulk mineralogy and lithology. Biostratigraphic and complete geochemical review has been undertaken from published papers and unpublished internal reports to better assess these important source intervals. [ABSTRACT FROM AUTHOR]

The Rejim Maatoug aquifer, which located in south-western Tunisia, constitutes a good example of overexploited resources. Hydrogeological and geochemical data were examined to determine the main factors and mechanisms controlling the groundwater chemistry and the hydrodynamic functioning of this aquifer based on a multi-tracer approach. Thirty-one groundwater samples from the CT Miocene aquifer of Rejim Maatoug and Djerid regions were collected in 2010 for major chemical element analysis. Physical parameters such as temperature, pH and electrical conductivity (EC) were measured in the field. Three groundwater samples were selected for 14 C measurements. Four groundwater samples were chosen for 3 H measurements. The chemical data indicates that dissolution of evaporate minerals, evaporation and cation exchange processes seem to be the main factors controlling groundwater mineralization. The geological and hydrogeological studies show the important role of the deep existing faults in controlling the hydrodynamic functioning of the aquifer systems in southern Tunisia. The isotopic data shows that groundwater in this area is a mixture of recent shallow waters located in the Mio-Plio-Quaternary sands and paleo-deep waters of the carbonate Senonian aquifer. Low 3 H and 14 C contents, observed in some sampled wells ( 3 H = 0.15 TU in C1N1, 14 C = 8.8 pmc in Matr2), indicates that the recharge of the Miocene aquifer occurs mainly through upflow leakage of Senonian deep aquifer while there is no evidence of significant recharge in major part of the plain and mountains piedmonts that can be observed. [ABSTRACT FROM AUTHOR]

Hydrogeological investigations in arid zones tend to be logistically difficult and costly. However, isotopic techniques can be used to gain valuable reconnaissance information, for example, in advance of new drilling programmes and also during exploitation. Thus, the most cost-effective exploration in arid zones will include both good hydrogeological data combined with isotopic and supporting geochemical information. The question of recharge is one of the most critical for groundwater management in dry areas. Is the recharge currently taking place and at what rate? If recharge is occurring, further important problems arise dealing with possible mechanisms of recharge, which may occur through direct infiltration, upward leakage, lateral recharge from areas of rainfall, and lateral seepage of river (Fontes and Edmunds, Technical documents in hydrology 77, ). In this study, which is of interest for an important aquifer system in southern Tunisia, conjunction of environmental isotopes, i.e.: O, H, H, C and C and chloride contents was used to understand the mode of recharge of the shallow Plio-Quaternary (PQ) and the intermediate Complexe Terminal (CT) aquifers. Both are unconfined in the vicinity of the Tozeur uplift and the Dahar upland and show relatively modern water that originated from present-day rainfall. It has been demonstrated that the Continental Intercalaire deep groundwater contributes to the CT aquifer recharge, the latter to the upper PQ shallow aquifer. The shallow PQ is mainly recharged by return flow irrigation and upward leakage in oases areas. Away from oases zones, sporadic recharge may occur at the inter-dunes especially between the Chott Djerid and Chott El Gharsa, in the Bir Roumi region and in the Kebili sand fields. [ABSTRACT FROM AUTHOR]

The current geochemical study of n-alkanes, steranes, and triterpanes in bitumen from the Late Maastrichtian-Paleocene El Haria organic-rich facies in West of Gafsa, southern Tunisia, was performed in order to characterize with accuracy their geochemical pattern. The type of organic matter as deduced from n-alkanes, steranes, and triterpanes distributions is type II/III mixed oil/gas prone organic matter. Isoprenoids and biomarkers maturity parameters (i.e., T/ T, 22S/(22S + 22R) of the C αβ-hopanes ratios, 20S/(20R + 20S) and ββ/(ββ + αα) of C steranes), revel that the organic-rich facies were deposited during enhanced anoxic conditions in southern Tunisa. The organic matter is placed prior to the peak stage of the conventional oil window (end of diagenesis-beginning of catagenesis). All these result are suggested by total organic carbon analysis, bitumen extraction and liquid chromatography data. Thus, the n-alkanes, triterpane, and steranes study remains valuable and practical for geochemical characterization of sedimentary organic matter. [ABSTRACT FROM AUTHOR]

The present study provides the first data available on imposex in a gastropod species caught offshore the Tunisian coast. Imposex was analysed in the purple dye murex (Bolinus brandaris,) from ten collecting sites offshore the Gulf of Gabès (southern Tunisia, Central Mediterranean Sea). From a total of 584 individuals analysed, females outnumbered males, leading to a female-biased sex ratio (1 F.0.7 M). Among the 353 females analysed, 117 were affected by imposex. On the whole, these females presented low to moderate imposex incidence (I%=33.1) and severity (FPLI=0.3, RPLI=2.6 and VDSI=0.8). The study revealed that imposex is a widespread phenomenon in the Gulf of Gabes and identified a clear inshore/offshore gradient in the imposex indices of B. brandaris. Regression analysis detected highly significant negative correlations between imposex indices and the distance to the coastline and depth of the collecting sites. Principal components analysis highlighted the specific influence of the distance to the major harbours, either in number of calling vessels (commercial harbour of Sfax) or shipping tonnage (oil terminal of Skhira). This inshore/offshore gradient of imposex development in B. brandaris reflects marked spatial variation in pollution by organotin compounds associated to the shipping activity. Overall, the study provides valuable baseline data for assessing the future evolution of imposex in B. brandaris, and subsequently the spatial and temporal trends of pollution by organotin compounds offshore the Gulf of Gabès. [ABSTRACT FROM AUTHOR]

Permian rock samples from four wells drilled in the Jeffara (J1 and J2) and Dahar (D1 and D2) areas of southern Tunisia were evaluated using the Rock-Eval® Shale Play™ method. Quantification of most liquid hydrocarbon compound families released at specific temperature range for the Sh0 and Sh1 as well as Sh2 and S3 parameters was achieved with subsequent calculations of appropriate indices. In addition, stable carbon isotopes evaluation of Permian samples was carried out in order to estimate the origin of their fossilized organic matter. Biomarker analyses were also undertaken on Permian samples and other proven Paleozoic source rocks samples of the study area (Ordovician Azzel and Upper Silurian Fegaguira formations) for comparison purposes. The results show that the Permian series encompass highly-rich organic matter intervals which may exceed 5%. The organic matter is of type II2-III, proven either by the Rock-Eval®, carbon isotopes and biomarker data. Permian samples from three wells (D1, D2, and J2) are found mostly at an early mature stage. Contrary, Permian samples from the J1 Well show abnormal T max temperatures testifying an overmature stage which could be related to abnormal heat flow around the Jeffara area. The depositional environment of the organic matter-rich Permian intervals is mainly suboxic of normal salinity, similar to the other Paleozoic investigated source rocks in the study area. Overall, this research comes to validate the occurrence within the Dahar and Jeffara areas of an active Permian oil/gas prone source rock, competitive to the other proven Paleozoic source rocks. [ABSTRACT FROM AUTHOR]

Groundwater is the most precious and valuable natural source of water in the southeast of Tunisia. The aim of this study is to find an adequate combination of methods for a qualitative description of geochemical processes into the Zeuss-Koutine, a Triassic and Miocene groundwater system, the unique source of water for this region of the Mediterranean (Medenine, Jerba, Zarzis and Jorf cities). Conventional classification techniques, statistical analyses and kriging methods were used to identify mineral processes distribution. This study finds that water chemistry is mainly dominated by dissolution/precipitation of minerals (calcite, dolomite, aragonite, anhydrite, gypsum and halite). Results obtained from principal component analyses (PCA) demonstrate that the variable responsible for water quality are largely related to soluble salts species (Na+, Cl-, Ca2+, Mg2+ and SO42-). On the basis of the hierarchical cluster analysis (HCA), three groundwater clusters have been distinguished : cluster 1 is low TDS (<1000 mg L-1) Ca2+ = Mg2+-Na+-SO42- waters which degrades into predominantly Na+-Ca2+-Cl--SO42- more saline groundwater (cluster 2) (TDS>3000 mg L-1 ) resulting from replacement of Ca by Na through cation exchange process on clay minerals. Cluster 3 is high TDS (>7000 mg L-1) NaCl waters from the aquifer system under confined conditions. Clusters 1 and 2 are located in preferential recharge zones whereas cluster 3 characterises downstream of the study area. Overall, a groundwater quality decrease has been observed similarly with a salinity increase from downstream to upstream towards the coast, where cation exchange processes and salinisation due to the long residence times appear to be the main processes responsible of more salty waters. [ABSTRACT FROM AUTHOR]