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Search Results: 1 - 10 of 10 matches for " Lhoussaine Bouchaou "
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Nitrate Contamination of Groundwater in Irrigated Perimeters under Arid Climate (The Case of Souss-Massa Aquifer, Morocco)
Tarik Tagma,Youssef Hsissou,Lhoussaine Bouchaou,Latifa Bouragba,Said Boutaleb
Environmental Research Journal , 2012,
Abstract: The objective of this study was to clarify, the current status of alluvial aquifer in the Souss-Massa basin, where, the nitric pollution of groundwater is being increasing along the last decades. A multi-approach methodology using hydrogeology, nitrate concentrations, irrigation mode and Oxygen-18 and Deuterium isotopes data, was carried out to identify the sources of this pollution. According to the spatial distribution of nitrate contents, nitric pollution occurs mainly in the Chtouka-Massa plain. More than 36% of the sampled wells exceed the value of 50 mg L-1 which, constitutes the threshold value of nitrate concentrations for drinking water Moroccan standards. The groundwater in Souss plain is less polluted comparing to Chtouka-Massa. Only 7% of wells exceed the permitted level. The widespread distribution of high nitrate contents agrees with the distribution of irrigated areas, which can explain the major origin from agricultural fertilizers. High nitrate levels are associated with high δ18O values, clearly indicating that significant quantities of evaporated (isotopically enriched) irrigation water infiltrate along with fertilizer nitrate to the groundwater system. Different δ18O-NO3- trends suggest isotopically distinct, non-point source origins, which vary spatially and temporally, due to different degrees of evaporation/recharge and amounts of fertilizer applied.
Chloridobis[2-(1,5-dimethyl-1H-pyrazol-3-yl-κN2)-1-methyl-1H-imidazole-κN3]copper(II) chloride methanol hemisolvate tetrahydrate
Lhoussaine El Ghayati,El Mostafa Tjiou,Lahcen El Ammari
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810000048
Abstract: In the title compound, [CuCl(C9H12N4)2]Cl·0.5CH3OH·4H2O, the CuII ion adopts a distorted trigonal-bipyramidal coordination arising from two bidentate ligands and a Cl anion. The two heterocyclic ligands are planar with dihedral angles of 3.4 (1) and 0.7 (1)° between the pyrazole and imidazole rings. In the crystal, water molecules and uncoordinated chloride anions form an O—H...Cl and O—H...O hydrogen-bonded sheet parallel to (100) which lies between two layers of complex molecules. The packing is further stabilized by C—H...Cl and C—H...O hydrogen bonds. The methanol solvent molecule is disordered across a centre of inversion.
Groundwater nitrate pollution in Souss-Massa basin (south-west Morocco)
T Tagma, Y Hsissou, L Bouchaou, L Bouragba, S Boutaleb
African Journal of Environmental Science and Technology , 2009,
Abstract: The objective of our study was to determine the current status of alluvial aquifer in the Souss-Massa basin, where the nitrate pollution of groundwater is being increasing along the last decades. A multiapproach methodology using hydrogeology, nitrate concentrations, irrigation type and oxygen-18 and deuterium data, was carried out to identify the sources of this pollution. According to the spatial distribution of nitrate contents, nitrate pollution occurs mainly in Chtouka-Massa plain. More than 36% of the sampled wells exceed the value of 50 mg/L as NO3 -. Groundwater in Souss plain is less polluted comparing it to Chtouka-Massa; only 7% of wells exceed the permitted level. Agricultural practices in the study sites are the main cause of serious nitrate pollution given the uperimposition of high nitrate concentrations with the distribution of irrigated perimeters. High nitrate levels are associated with high 18O values, clearly indicating that significant quantities of evaporated irrigation waters infiltrate along with fertilizer nitrate to groundwater system. Different 18O-NO3 - trends suggest isotopically distinct, non-point source origins which vary spatially and temporally, due to different degrees of evaporation/recharge and amounts of fertilizer applied.
Characterization of groundwater in the Souss upstream basin: Hydrochemical and environmental isotopes approaches
L Bouragba, MJ Jacques, L Bouchaou, Y Hsissou, T Tagma
African Journal of Environmental Science and Technology , 2011,
Abstract: The hydrochemistry of major ions and environmental isotope compositions (18O, 2H) of water samples have been used to identify the chemical characteristics and the origin of groundwater in the Souss upstream basin. The total dissolved solids (TDS) did not exceed 1000 mg.L-1 with an average of 635 mg.L-1. Two chemical water types were observed: A calcium and magnesium bicarbonate type (Ca2+-Mg2+-HCO3-), forming the dominant water type generally observed in the plain along the Souss river and towards the piedmont of the Anti-Atlas Mountains; and a calcium sulphate type (Ca2+-SO42-), from the northwest of the study area, linked to the presence of phosphatic gypseous marls and limestone marls (Upper Cretaceous). The calculations of saturation indexes versus the main mineral phases have been carried out, using the PHREEQC program. The groundwater is saturated and slightly oversaturated with respect to carbonate minerals and under saturated with respect to evaporite minerals; surface waters show an oversaturation with respect to carbonate mineral phases, mainly dolomite. The groundwater composition is largely controlled by the dissolution of carbonate rocks known in this part of the basin. Stable isotope contents of groundwaters ranged from -7.96 to -6.26‰ for δ18O and from -49.47 to -39.28‰ for δD. The hydrogen (δD) and oxygen (δ18O) isotope signatures indicate a low evaporation of precipitations during infiltration and that the aquifer is highly influenced by the contribution of recharge water recharge from the High Atlas Mountains.
Capillary rise quantification by field injection of artificial deuterium and laboratory soil characterization
O. Grünberger,J. L. Michelot,L. Bouchaou,P. Macaigne
Hydrology and Earth System Sciences Discussions , 2010, DOI: 10.5194/hessd-7-7757-2010
Abstract: In arid contexts, water rises from the saturated level of a shallow aquifer to the drying soil surface where evaporation takes place. This process plays important roles in terms of plant survival, salt balance and aquifer budget. A new field quantification method of this capillary rise flow is proposed using micro-injections (6 μL) of deuterium-enriched solution (δ value of 63 000‰ vs. V-SMOW) into unsatured soil at 1 m depth. Evaluation of peak displacement from a profile sampling 35 days later, delivered estimates that were compared with outputs of numerical simulation based on laboratory hydrodynamic measurements. A rate of 3.7 cm y 1 was observed in a Moroccan site where the aquifer level was 2.44 m deep. This value was higher, than other estimates based on natural diffusion with the same depth of aquifer, but lower than the estimates established using integration of van Genutchen closed-form functions for soil hydraulic conductivity and retention curve.
Comportement des métaux et fonctionnement d’un estuaire en zone sub aride : cas de l’estuaire du Souss (c te atlantique Marocaine)
Wildi, W.,Snoussi, M.,Bouchaou, L.,Elmouden, A.
Estudios Geologicos , 2005, DOI: 10.3989/egeol.05611-239
Abstract: Selected trace metals (Pb, Zn, Cu, Ni and Cr) were studied in surface sediments and cores from the Souss wadi estuary. Trace metal concentrations in riverine and effluent SPM, and in down-the estuary, bed sediments, show that Cr and Ni have a geological origin, while, Pb, Zn and Cu apparently are anthropogenic. The concentration of most metals in down-the estuary sediments diminish in relation to the regional geochemical background by scavenging effects and desorption processes. The vertical distributions of trace metals show an enrichment in finer grained horizons ascribed to the diffusive flux of metals and their retention by the clay-rich layers. The estuary does not constitute a trap for polluting metals as occurs in wet climates. However, the mud flats sedimentary column records a slight increase in polluting elements. The transit of these metals towards the seawater could generate a risk for the aquatic life and for the surrounding beaches. Pour comprendre la distribution et le transfert des métaux lourds à l’interface eau douce - eau salée sous climat sub-aride, les métaux Pb, Zn, Cu, Ni et Cr ont été analysés dans les sédiments superficiels et dans deux carottes prélevées au niveau de la slikke de l’estuaire de l’oued Souss qui est soumis en plus au rejet d’un effluent urbain. La comparaison des concentrations en métaux dans les matières en suspension fluviatiles, celles de l’effluent urbain et dans les sédiments superficiels du bas estuaire montre que Cr et Ni ont une origine lithogénique alors que Pb, Zn et Cu auraient une origine anthropique. Les teneurs de la majorité des métaux montrent un appauvrissement vers l’aval en comparaison avec le fond géochimique naturel. Cet appauvrissement a été expliqué par un phénomène de solubilisation des métaux liés à la phase particulaire et au balayage par les courants de marées des particules sédimentées sur la slikke et appauvries en métaux. La distribution des teneurs en métaux dans les carottes montre un enrichissement dans les horizons à granulométrie fine attribué une migration des métaux par diagenèse précoce et leurs rétention dans les couches argileuses, et aussi probablement au contr le par les conditions oxydo-réductrices du milieu. L’estuaire du Souss ne joue pas donc un r le de piége vis-à-vis des métaux polluants comme c’est le cas de nombreux estuaires des zones tempérées. Par contre, la colonne sédimentaire de la slikke enregistre une légère augmentation des teneurs en éléments métalliques qui pourraient constituer un risque pour la vie aquatique et pour la salubrité des plages environnant
Determination of recharge modes of aquifers by use of chemical and isotopic tracers. Case study of the contact zone between Western High-Atlas Chain and Souss Plain (SW Morocco)
Boutaleb, S.,Bouchaou, L.,Hsissou, Y.,Tagma, T.
Estudios Geologicos , 2008, DOI: 10.3989/egeol.08641459
Abstract: Determination of the origin of recharge of the unconfined aquifer in the right side of the Souss wadi between Agadir and Taroudant (South-western of Morocco) was based on the use of hydrochemical and isotopic analysis of groundwater, surface water and springs of the contact zone between the High-Atlas Chain and the Souss plain. The correspondence in the space evolution of the various chemical elements of evaporitic origin (SO42-, Cl-, Sr2+) in groundwater, piedmont springs, and surface water reveals the existence of recharge water from the adjacent High-Atlas Chain. The various recharge modes of the different aquifers (High Atlas and Souss plain) determined by isotopic analysis, shows that the source of groundwater for the unconfined Souss aquifer seems to be composite between a direct infiltration on the High-Atlas tributaries and a remote recharge from the bordering High Atlas aquifers. La determinación del origen de los aportes de agua de la capa freática de la ribera derecha del rio Souss entre Agadir y Taroudant (Suroeste de Marruecos) se ha basado en la hidroquímica y el análisis isotópico de las aguas subterráneas, aguas superficiales y manantiales de la zona de contacto entre el Alto Atlas y la llanura de Souss. La correspondencia en la evolución espacial de los diferentes elementos químicos de origen evaporítico (SO42-, Cl-, Sr2+) en las aguas subterráneas, manantiales de pie de monte y aguas superficiales, revela la existencia de una recarga de agua procedente de la cadena del Alto Atlas. El análisis de los modos de recarga de los diferentes acuíferos (Alto Atlas y llanura de Souss) determinado por análisis isotópico, demuestra que la alimentación de la capa freática de Souss a partir del Alto Atlas parece ser mixta, compuesta por una infiltración directa de los afluentes del Alto Atlas y una alimentación lejana desde los acuiferos que limitan con el borde del Alto Atlas.
Groundwater Protection Using DRASTIC Vulnerability Maps and ArcFem Tools for Perimeter Protection: A Case Study in the Charf El Akab Aquifer (Morocco North)  [PDF]
Moulay Lhassan Sadiki, Lhoussaine El Mezouary, Abdelaziz Khomsi, Badr Benseddik, El Houssine El Gasmi, Mohamed El Bouhaddioui, Malika Kili, Jamal Chao, Bouabid El Mansouri, Aicha Benmohammadi
International Journal of Geosciences (IJG) , 2018, DOI: 10.4236/ijg.2018.96018
Abstract: The Charf El Akab aquifer has a surface area of 17 km2 and is located about 20 km southwest of the Tangier city, it circulates in the Miocene sandy basin of the same name and comprises two layers, one high and the other low, these two are separated in some places by an airtight impenetrable sand-marly formation. The requirements for water whether potable or industrial, in the Tangier-Asilah region are expected to amplify in order to support the increasing demand prompted by the economical development, population growth as well as the heightened threat of scarcity related to climate change. Currently, the water supply of this region is ensured mostly by the two dams: Ibn Battouta and “April 9, 1947”. However, this aquifer plays the role of an easily usable emergency reservoir, in case of an extra water supply in rush hour or in the event where current service works of the cities of Tangier and Asilah are unavailable. Nevertheless, water resources are still vulnerable because of the existence of abandoned quarries in the area. Therefore, the protection of this aquifer against any source of pollution is the purpose of this work. The lower water layer is the only one that can be exploited by the ONEE (National Office for Electricity and Drinking Water), due to the fact that it has a better quality and very good hydrodynamic characteristics. The most important thing about this work is the establishment of an intrinsic vulnerability map to the pollution by the DRASTIC method, by exploiting of the calibrated hydrodynamical model results. In the same context of protection, a guesstimate of the close protection perimeter of 72.76 ha was acquired, using a new numerical modeling approach by the “Arcfem” software under the ArcMap environment.
Theoretical basis of the community effect in development
Yasushi Saka, Cédric Lhoussaine, Celine Kuttler, Ekkehard Ullner, Marco Thiel
BMC Systems Biology , 2011, DOI: 10.1186/1752-0509-5-54
Abstract: In this work, we propose a model of the community effect in development, which consists in a linear gene cascade and cell-cell communication. We examined the properties of the model theoretically using a combination of stochastic and deterministic modelling methods. We have derived the analytical formula for the threshold size of a cell population that is necessary for a community effect, which is in good agreement with stochastic simulation results.Our theoretical analysis indicates that a simple model with a linear gene cascade and cell-cell communication is sufficient to reproduce the community effect in development. The model explains why a community needs many cells. It suggests that the community's long-term behaviour is independent of the initial induction level, although the initiation of a community effect requires a sufficient amount of inducing signal. The mechanism of the community effect revealed by our theoretical analysis is analogous to that of quorum sensing in bacteria. The community effect may underlie the size control in animal development and also the genesis of autosomal dominant diseases including tumorigenesis.During embryonic development, cell-cell interaction plays a pivotal role in generating many types of cells that constitute a functional adult body. The most prevalent of such interaction is embryonic induction, a process by which part of a tissue within the embryo changes its direction of differentiation into another upon receipt of a signal emanating from the nearby tissue. Such induction events, however, are transient and therefore the cells that have received the signal must 'remember' the event until they terminally differentiate.The precursor cells generated by an embryonic induction tend to stay together and form a cell group of like character. Despite the fact that those cells often proliferate and their surrounding environment changes as a consequence of morphogenesis, cells in such a group behave as a collective and express the
Capillary rise quantifications based on in-situ artificial deuterium peak displacement and laboratory soil characterization
O. Grünberger, J. L. Michelot, L. Bouchaou, P. Macaigne, Y. Hsissou,C. Hammecker
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011,
Abstract: In arid environments, water rises from the saturated level of a shallow aquifer to the drying soil surface where evaporation occurs. This process plays important roles in terms of plant survival, salt balance and aquifer budget. A new field quantification method of this capillary rise flow is proposed using micro-injections (6 μL) of a deuterium-enriched solution (δ value of 63 000‰ vs. V-SMOW) into unsaturated soil at a 1 m depth. Evaluation of peak displacement from profile sampling 35 days later delivered an estimate that was compared with outputs of numerical simulation based on laboratory hydrodynamic measurements assuming a steady state regime. A rate of 3.7 cm y 1 was estimated at a Moroccan site, where the aquifer water depth was 2.44 m. This value was higher than that computed from the relationship between evaporation rates and water level depth based on natural isotopic profile estimates, but it was lower than every estimate established using integration of the van Genuchten closed-form functions for soil hydraulic conductivity and retention curve.
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