The Korba region in northwestern Tunisia has a coastal aquifer that is impacted by intensive irri... more The Korba region in northwestern Tunisia has a coastal aquifer that is impacted by intensive irrigation, urban expansion, and sensitivity to SWI. We assessed the vulnerability extent of Korba’s GW to SWI. We utilized a parametric model for GW vulnerability assessment, the GALDIT, which considers six parameters to determine SWI effects. The GALDIT map has four rating categories (≥7.5, 7.5–5, 5–2.5, and <2.5), representing very high, high, moderate, and low vulnerability, respectively. Most of the region was found to be highly vulnerable (44.2% of the surface area), followed by areas characterized by very high (20.3%) and moderate (19.3%) vulnerability. Only 16.2% was found to have low vulnerability. A parameter sensitivity analysis showed that distance from shore and depth of GW represent the determining factors for SWI with variation index values of 24.12 and 18.02%, respectively. Inland advancement of seawater is causing GW salinity to rise, as indicated by a strong Pearson corr...
In numerous coastal aquifers, particularly in semi-arid and arid regions, the salinization of gro... more In numerous coastal aquifers, particularly in semi-arid and arid regions, the salinization of groundwaters is of strategic water resource importance, since it places limitations of the use of the water for urban water supply and agricultural use. The hydrochemical differentiation of the salinization processes is very complex as there is considerable hydrochemical variability due to superposition of different processes: marine intrusion, recycling of wastewaters, continental saltwater contribution and pollution phenomena by agricultural activities. In this book, we try to describe the hydrological processes in the Korba coastal plain (NE of Tunisia) using hydrochemical data, correlation matrices and factor analysis to provide evidence of salinization processes. The application of Multivariate Statistics Techniques based on Principal component Analysis and Hierarchical Cluster Analysis has lead to the corroboration of the hypotheses developed from the hydrochemical study. Two factors ...
Mapping groundwater recharge zones (GWRZs) is essential for planning artificial recharge programs... more Mapping groundwater recharge zones (GWRZs) is essential for planning artificial recharge programs to mitigate groundwater decline and saltwater intrusion into coastal aquifers. We applied two multi-criteria decision-making approaches, namely the analytical hierarchy process (AHP) and the multi-influencing factors (MIF), to map GWRZs in the Korba aquifer in northeastern Tunisia. GWRZ results from the AHP indicate that the majority (69%) of the area can be classified as very good and good for groundwater recharge. The MIF results suggest larger (80.7%) very good and good GWRZs. The GWRZ maps improve groundwater balance calculations by providing estimates of recharge-precipitation ratios to quantify percolation. Lithology, land use/cover and slope were the most sensitive parameters followed by geomorphology, lineament density, rainfall, drainage density and soil type. The AHP approach produced relatively more accurate results than the MIF technique based on correlation of the obtained ...
Inundations represent one of the most impactful and hazardous natural disasters, leading to exten... more Inundations represent one of the most impactful and hazardous natural disasters, leading to extensive loss of life and property. The establishment of flood susceptibility map is highly needed for risk prevention. This research takes Chafrou watershed, NE Tunisia as the study area. Five influencing criteria including Rainfall, Land use/Land cover, Slope, lithology and Streams Network was selected and processed utilizing GIS based on Multi-criteria Decision Making model (MCDM) via the analytical hierarchy process (AHP) method to carry out the flood hazard susceptibility model and estimated the Flood Hazard potential Index (FHI). The approach used in the weight calculation is the prioritized by pairwise comparison (PWC). The application of the proposed approach shows that the land use / Land cover is the most influencing parameter flooding with weight order 35%, followed by the Slope (27%). The flood susceptibility model elaborated shows that the study area is subdivided in five catego...
Located in the southeastern region of Morocco, the Zagora area mainly relies on groundwater as a ... more Located in the southeastern region of Morocco, the Zagora area mainly relies on groundwater as a source of water supply. However, this groundwater is often of concern, due to the limited recharge and unfavorable geological conditions for the development of the aquifer. Despite this, private wells in the Zagora ditch reveal relatively rich water resources. Geochemical and isotopic studies were conducted in the area to understand the origin of the groundwater and its salinity, aiding in informed water management strategies to assist in better planning and regulation of well construction, as well as in mitigating the impacts of high salinity on local water supply and agricultural systems. The results show that the water quality varies, with some wells having conductivity values in excess of 5 mS/cm. Most groundwater samples have high salinity and low pH due to the CO2 dissolved in groundwater. Geochemical analysis indicated two chemical facies: chloride–sulfate calcic/magnesic and bica...
In order to assess the relationship between the groundwater mineralization of Roc-Blanc watershed... more In order to assess the relationship between the groundwater mineralization of Roc-Blanc watershed (Morocco), lithology, fracturation and abandoned mine tailings in the area, a multidisciplinary work was conducted by using the geochemical assessment approaches. Geological and hydrochemical results showed the following: (i) the main direction of fractures and the groundwater flow investigations reveal hydrogeological structures as dividing axis according to the SE and NW directions; (ii) correlations between the principal elements (Cl−, SO42−; Na+, Cl−) indicate that the mineralization of the Roc-Blanc groundwater is deduced from sulphates, chlorides and alkaline formations and iii) the dissolution of carbonate, gypsum and anhydrite constitutes the principal source of the mineralization processes. The saturation index shows that dissolution of gypsum and anhydrite is one of the origins of sulphates and calcium in the water resources of the study area. Abandoned mine tailings have no effects on the groundwater quality.
Dans cette note, nous présentons les premiers résultats hydrochimiques de la nappe de la Mamora. ... more Dans cette note, nous présentons les premiers résultats hydrochimiques de la nappe de la Mamora. Les données recueillies permettent de déterminer la minéralisation globale qui se caractérise par une conductivité électrique variable (entre 595 à 2930 µS.cm-1). La distribution spatiale de cette dernière met en évidence un découpage de la nappe en trois zones où la minéralisation est importante. La corrélation réalisée entre les paramètres chimiques et la conductivité électrique est généralement bonne. Elle révèle la probabilité d'une intrusion marine.
The hydrodynamic dispersion tensor (HDT) of a porous medium is a key parameter in engineering and... more The hydrodynamic dispersion tensor (HDT) of a porous medium is a key parameter in engineering and environmental sciences. Its knowledge allows for example, to accurately predict the propagation of a pollution front induced by a surface (or subsurface) flow. This paper proposes a new mathematical model based on inverse problem-solving techniques to identify the HDT (noted D=) of the studied porous medium. We then showed that in practice, this new model can be written in the form of an integrated optimization algorithm (IOA). The IOA is based on the numerical solution of the direct problem (which solves the convection–diffusion type transport equation) and the optimization of the error function between the simulated concentration field and that observed at the application site. The partial differential equations of the direct model were solved by high resolution of (Δx=Δy=1 m) Lattice Boltzmann Method (LBM) whose computational code is named HYDRODISP-LBM (HYDRO-DISpersion by LBM). As ...
The present paper proposes the numerical solution of an inverse problem in groundwater flow (Darc... more The present paper proposes the numerical solution of an inverse problem in groundwater flow (Darcy’s equation). This solution was achieved by combining a high-resolution new code HYSFLO-LBM (Hydrodynamic of Subsurface Flow by Lattice Boltzmann Method), based on LBM, to solve the direct problem, and the metaheuristic optimization algorithm CMA-ES ES (Covariance Matrix Adaptation-Evolution Strategy) to solve the optimization step. The integrated optimization algorithm which resulted from this combination, HYSFLO-LBM/CMA-ES, was applied to the hydrogeological experimental site of Beauvais (Northern France), instrumented by a set of sensors distributed over 20 hydrogeological wells. Hydrogeological parameters measured by the sensors are necessary to understand the aquifer functioning and to serve as input data for the identification of the transmissivity field by the HYSFLO-LBM/CMA-ES code. Results demonstrated an excellent concordance between the integrated optimization algorithm and h...
A survey of the salinity of the Rharb basin groundwater in western Morocco is based on a spatial ... more A survey of the salinity of the Rharb basin groundwater in western Morocco is based on a spatial partition of several physico-chemical parameters. Marine intrusion and the lithological composition of the saline Pre-Rifean nappes, combined with their tectonic structures and their flow towards the Rharb basin, are considered as increasing factors for the salinity of the underground resources of the area. The partition of the basin in several zones highlighted strong gradients of electrical conductivity and chloride concentrations, in particular in the eastern portion. The correlations between these two parameters are generally good.
Hydrological Sciences Journal-journal Des Sciences Hydrologiques, 2002
The aim is to correlate variations in the piezometric levels, to examine the hydrogeological func... more The aim is to correlate variations in the piezometric levels, to examine the hydrogeological functions of the Mamora coastal basin and to reconstruct the geometrical configuration of its aquifer. This study is based on the combined use of the hydrogeological, geophysical and structural approaches. The spatial and temporal analysis of the piezometry highlighted a variation in the groundwater behaviour and heterogeneity of the piezometric levels. The faults in the NE-SW and NW-SE directions, identified during this work, make it possible to consider the existence of a block system, which would explain the shift between the Plio-Quaternary compartments and the differences in the piezometric levels between the northern and southern parts of this aquifer.
La region de la mamora (maroc) est caracterisee par un potentiel hydraulique souterrain qui repre... more La region de la mamora (maroc) est caracterisee par un potentiel hydraulique souterrain qui represente la seule ressource en eau de la region. Sa nappe alimente principalement l'agglomeration de kenitra et rabat, la capitale administrative. Suite a la croissance agricole et industrielle de la region, la presente these a pour but de comprendre la structure de l'aquifere, afin d'etablir un modele hydrodynamique qui permette une gestion des ressources en eau de la region. La configuration geometrique a ete realisee a partir de plusieurs methodes directes et indirectes : lithostratigraphiques, geophysiques (electriques et sismique-reflexion). L'interpretation structurale a mis en evidence une structure en horsts et grabens controlee par des failles hercyniennes appartenant a deux familles sub-perpendiculaires paralleles aux failles agadir-rabat (n020\e-040\e) et rabat-tiflete (n o120\e). Une faille supplementaire, detectee par l'etude des profils sismiques, divise la...
The Korba region in northwestern Tunisia has a coastal aquifer that is impacted by intensive irri... more The Korba region in northwestern Tunisia has a coastal aquifer that is impacted by intensive irrigation, urban expansion, and sensitivity to SWI. We assessed the vulnerability extent of Korba’s GW to SWI. We utilized a parametric model for GW vulnerability assessment, the GALDIT, which considers six parameters to determine SWI effects. The GALDIT map has four rating categories (≥7.5, 7.5–5, 5–2.5, and <2.5), representing very high, high, moderate, and low vulnerability, respectively. Most of the region was found to be highly vulnerable (44.2% of the surface area), followed by areas characterized by very high (20.3%) and moderate (19.3%) vulnerability. Only 16.2% was found to have low vulnerability. A parameter sensitivity analysis showed that distance from shore and depth of GW represent the determining factors for SWI with variation index values of 24.12 and 18.02%, respectively. Inland advancement of seawater is causing GW salinity to rise, as indicated by a strong Pearson corr...
In numerous coastal aquifers, particularly in semi-arid and arid regions, the salinization of gro... more In numerous coastal aquifers, particularly in semi-arid and arid regions, the salinization of groundwaters is of strategic water resource importance, since it places limitations of the use of the water for urban water supply and agricultural use. The hydrochemical differentiation of the salinization processes is very complex as there is considerable hydrochemical variability due to superposition of different processes: marine intrusion, recycling of wastewaters, continental saltwater contribution and pollution phenomena by agricultural activities. In this book, we try to describe the hydrological processes in the Korba coastal plain (NE of Tunisia) using hydrochemical data, correlation matrices and factor analysis to provide evidence of salinization processes. The application of Multivariate Statistics Techniques based on Principal component Analysis and Hierarchical Cluster Analysis has lead to the corroboration of the hypotheses developed from the hydrochemical study. Two factors ...
Mapping groundwater recharge zones (GWRZs) is essential for planning artificial recharge programs... more Mapping groundwater recharge zones (GWRZs) is essential for planning artificial recharge programs to mitigate groundwater decline and saltwater intrusion into coastal aquifers. We applied two multi-criteria decision-making approaches, namely the analytical hierarchy process (AHP) and the multi-influencing factors (MIF), to map GWRZs in the Korba aquifer in northeastern Tunisia. GWRZ results from the AHP indicate that the majority (69%) of the area can be classified as very good and good for groundwater recharge. The MIF results suggest larger (80.7%) very good and good GWRZs. The GWRZ maps improve groundwater balance calculations by providing estimates of recharge-precipitation ratios to quantify percolation. Lithology, land use/cover and slope were the most sensitive parameters followed by geomorphology, lineament density, rainfall, drainage density and soil type. The AHP approach produced relatively more accurate results than the MIF technique based on correlation of the obtained ...
Inundations represent one of the most impactful and hazardous natural disasters, leading to exten... more Inundations represent one of the most impactful and hazardous natural disasters, leading to extensive loss of life and property. The establishment of flood susceptibility map is highly needed for risk prevention. This research takes Chafrou watershed, NE Tunisia as the study area. Five influencing criteria including Rainfall, Land use/Land cover, Slope, lithology and Streams Network was selected and processed utilizing GIS based on Multi-criteria Decision Making model (MCDM) via the analytical hierarchy process (AHP) method to carry out the flood hazard susceptibility model and estimated the Flood Hazard potential Index (FHI). The approach used in the weight calculation is the prioritized by pairwise comparison (PWC). The application of the proposed approach shows that the land use / Land cover is the most influencing parameter flooding with weight order 35%, followed by the Slope (27%). The flood susceptibility model elaborated shows that the study area is subdivided in five catego...
Located in the southeastern region of Morocco, the Zagora area mainly relies on groundwater as a ... more Located in the southeastern region of Morocco, the Zagora area mainly relies on groundwater as a source of water supply. However, this groundwater is often of concern, due to the limited recharge and unfavorable geological conditions for the development of the aquifer. Despite this, private wells in the Zagora ditch reveal relatively rich water resources. Geochemical and isotopic studies were conducted in the area to understand the origin of the groundwater and its salinity, aiding in informed water management strategies to assist in better planning and regulation of well construction, as well as in mitigating the impacts of high salinity on local water supply and agricultural systems. The results show that the water quality varies, with some wells having conductivity values in excess of 5 mS/cm. Most groundwater samples have high salinity and low pH due to the CO2 dissolved in groundwater. Geochemical analysis indicated two chemical facies: chloride–sulfate calcic/magnesic and bica...
In order to assess the relationship between the groundwater mineralization of Roc-Blanc watershed... more In order to assess the relationship between the groundwater mineralization of Roc-Blanc watershed (Morocco), lithology, fracturation and abandoned mine tailings in the area, a multidisciplinary work was conducted by using the geochemical assessment approaches. Geological and hydrochemical results showed the following: (i) the main direction of fractures and the groundwater flow investigations reveal hydrogeological structures as dividing axis according to the SE and NW directions; (ii) correlations between the principal elements (Cl−, SO42−; Na+, Cl−) indicate that the mineralization of the Roc-Blanc groundwater is deduced from sulphates, chlorides and alkaline formations and iii) the dissolution of carbonate, gypsum and anhydrite constitutes the principal source of the mineralization processes. The saturation index shows that dissolution of gypsum and anhydrite is one of the origins of sulphates and calcium in the water resources of the study area. Abandoned mine tailings have no effects on the groundwater quality.
Dans cette note, nous présentons les premiers résultats hydrochimiques de la nappe de la Mamora. ... more Dans cette note, nous présentons les premiers résultats hydrochimiques de la nappe de la Mamora. Les données recueillies permettent de déterminer la minéralisation globale qui se caractérise par une conductivité électrique variable (entre 595 à 2930 µS.cm-1). La distribution spatiale de cette dernière met en évidence un découpage de la nappe en trois zones où la minéralisation est importante. La corrélation réalisée entre les paramètres chimiques et la conductivité électrique est généralement bonne. Elle révèle la probabilité d'une intrusion marine.
The hydrodynamic dispersion tensor (HDT) of a porous medium is a key parameter in engineering and... more The hydrodynamic dispersion tensor (HDT) of a porous medium is a key parameter in engineering and environmental sciences. Its knowledge allows for example, to accurately predict the propagation of a pollution front induced by a surface (or subsurface) flow. This paper proposes a new mathematical model based on inverse problem-solving techniques to identify the HDT (noted D=) of the studied porous medium. We then showed that in practice, this new model can be written in the form of an integrated optimization algorithm (IOA). The IOA is based on the numerical solution of the direct problem (which solves the convection–diffusion type transport equation) and the optimization of the error function between the simulated concentration field and that observed at the application site. The partial differential equations of the direct model were solved by high resolution of (Δx=Δy=1 m) Lattice Boltzmann Method (LBM) whose computational code is named HYDRODISP-LBM (HYDRO-DISpersion by LBM). As ...
The present paper proposes the numerical solution of an inverse problem in groundwater flow (Darc... more The present paper proposes the numerical solution of an inverse problem in groundwater flow (Darcy’s equation). This solution was achieved by combining a high-resolution new code HYSFLO-LBM (Hydrodynamic of Subsurface Flow by Lattice Boltzmann Method), based on LBM, to solve the direct problem, and the metaheuristic optimization algorithm CMA-ES ES (Covariance Matrix Adaptation-Evolution Strategy) to solve the optimization step. The integrated optimization algorithm which resulted from this combination, HYSFLO-LBM/CMA-ES, was applied to the hydrogeological experimental site of Beauvais (Northern France), instrumented by a set of sensors distributed over 20 hydrogeological wells. Hydrogeological parameters measured by the sensors are necessary to understand the aquifer functioning and to serve as input data for the identification of the transmissivity field by the HYSFLO-LBM/CMA-ES code. Results demonstrated an excellent concordance between the integrated optimization algorithm and h...
A survey of the salinity of the Rharb basin groundwater in western Morocco is based on a spatial ... more A survey of the salinity of the Rharb basin groundwater in western Morocco is based on a spatial partition of several physico-chemical parameters. Marine intrusion and the lithological composition of the saline Pre-Rifean nappes, combined with their tectonic structures and their flow towards the Rharb basin, are considered as increasing factors for the salinity of the underground resources of the area. The partition of the basin in several zones highlighted strong gradients of electrical conductivity and chloride concentrations, in particular in the eastern portion. The correlations between these two parameters are generally good.
Hydrological Sciences Journal-journal Des Sciences Hydrologiques, 2002
The aim is to correlate variations in the piezometric levels, to examine the hydrogeological func... more The aim is to correlate variations in the piezometric levels, to examine the hydrogeological functions of the Mamora coastal basin and to reconstruct the geometrical configuration of its aquifer. This study is based on the combined use of the hydrogeological, geophysical and structural approaches. The spatial and temporal analysis of the piezometry highlighted a variation in the groundwater behaviour and heterogeneity of the piezometric levels. The faults in the NE-SW and NW-SE directions, identified during this work, make it possible to consider the existence of a block system, which would explain the shift between the Plio-Quaternary compartments and the differences in the piezometric levels between the northern and southern parts of this aquifer.
La region de la mamora (maroc) est caracterisee par un potentiel hydraulique souterrain qui repre... more La region de la mamora (maroc) est caracterisee par un potentiel hydraulique souterrain qui represente la seule ressource en eau de la region. Sa nappe alimente principalement l'agglomeration de kenitra et rabat, la capitale administrative. Suite a la croissance agricole et industrielle de la region, la presente these a pour but de comprendre la structure de l'aquifere, afin d'etablir un modele hydrodynamique qui permette une gestion des ressources en eau de la region. La configuration geometrique a ete realisee a partir de plusieurs methodes directes et indirectes : lithostratigraphiques, geophysiques (electriques et sismique-reflexion). L'interpretation structurale a mis en evidence une structure en horsts et grabens controlee par des failles hercyniennes appartenant a deux familles sub-perpendiculaires paralleles aux failles agadir-rabat (n020\e-040\e) et rabat-tiflete (n o120\e). Une faille supplementaire, detectee par l'etude des profils sismiques, divise la...
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