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RésuméCette étude vise à améliorer la connaissance de la structure du bassin de Bou-Houria en se basant sur l’analyse et l’interprétation de données gravimétriques. Des cartes de l’anomalie résiduelle, du gradient vertical et du gradient horizontal ont été calculées à partir de la carte de l’anomalie de Bouguer. Ces cartes fournissent des informations sur la variation de la densité dans le sous-sol et permettent de mieux cerner la structure de la zone d’étude en mettant en évidence les principales unités et accidents tectoniques généralement masqués par les dépôts quaternaires. L’ensemble des résultats obtenus conduit à l’amélioration de la carte structurale de la zone d’étude, qui pourrait constituer un document de base pour orienter les futurs travaux d’exploration des eaux souterraines dans le bassin. 相似文献
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Lamyaa Kacem Mbark Agoussine Brahim Igmoullan Soraya Mokhtari Hicham Amar 《Water Resources》2016,43(2):395-401
The National Park of Toubkal is located in the High Moroccan Atlas Mountains, one of the regions sheltering the highest summits of North Africa (Mount Toubkal with an elevation of 4167 m). The park is characterized by very important water resources, including Ifni Lake, which is the highest natural lake in Morocco (with an elevation of 2320 m). This lake is located on the southern side of Mt. Toubkal. This area has never been the object of an environmental or hydrological study. The objective of the current study was the characterization of Ifni Lake and the spring waters located in this area, as the basis of a framework to protect natural resources in northern Africa. The hydrochemical composition of water determines its origin and relationship with its catchment. Hydrochemical studies were carried out to assess the ions water composition, and processes governing the hydrochemistry of Ifni Lake water and the springs in the study area. A total of 20 water samples were collected in 2013 and analyzed for various parameters such as pH, electrical conductivity, and major ions. The physico-chemical analysis of the Ifni Lake water showed that this is the least mineralized water studied in this region, having a bicarbonate, calcium, and magnesium as dominate ions. Also there is a relationship between the hydrochemical composition of Ifni Lake and spring waters. 相似文献
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Hicham El Bakouri Jos Morillo Jos Usero Abdelhamid Ouassini 《Journal of Hydrology》2008,353(3-4):335-342
The heavy use of pesticides in agriculture has meant that the fate due to their movement after their application continue to be a real problem for the environment. In this work, a viable eco-remediation technique based on the use of natural organic substances (NOS) that characterize the Mediterranean region is proposed to demonstrate the efficiency of endosulfan sulphate removal from water. Experimental results showed that the pH of pesticide solutions and temperature negatively affect the adsorption process. According to adsorption kinetic data, 5 h were considered as the equilibrium time for realizing adsorption isotherm. The Freundlich isotherm model describes better the adsorption process of endosulfan sulphate on NOS tested. The Freundlich constant Kf depended mainly on the nature of each adsorbent and ranged from 5.56 for straw to 13.54 for date stones. The adsorption tests gave very satisfying results and point to the possible application of these supports as an ecological remediation technique to reduce pesticide contamination of aquatic ecosystems. 相似文献
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This paper examines the status of traditional agriculture in two areas of Azilal province in the Atlas Mountains, seeking to identify what is needed to counter any breakdown in livelihood strategies and improve the quality of life enjoyed by the farmers. Irrigated terrace agriculture is an important part of livelihood strategies in the areas studied and has the potential to be more productive and sustainable. In some areas it is reported to be endangered by socioeconomic changes and highland land degradation caused by excessive shifting cultivation, sheep and goat grazing, and charcoal production. Field visits made during summer 1998 to establish the condition of irrigated terrace and runoff agriculture and the factors affecting it showed that in at least one of the villages supportive social capital has ensured that challenges are being met and beneficial innovations are being made. Considerable variation in success was evident from community to community, with some farmers maintaining adequate lifestyles and innovating, while in other communities prospects are less promising. The effects of structural adjustment have clearly been felt and may also have triggered some of the highland degradation and difficulties, which clearly threaten some irrigated terrace agriculture and other livelihood practices. 相似文献
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Raji Otmane Ouabid Muhammad Bodinier Jean-Louis El Messbahi Hicham Malainine Cheikh Elwali Tabbakh Zineb 《Natural Resources Research》2021,30(5):3219-3239
Natural Resources Research - Potassium (K)-rich igneous rocks include a variety of silica-undersaturated and alkaline rocks, which distinguished by their elevated K2O contents. These rocks have... 相似文献
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Fniguire Fatima Laftouhi Nour-Eddine Saidi Mohamed Elmehdi Zamrane Zineb El Himer Hicham Khalil Nourddine 《Theoretical and Applied Climatology》2017,129(1-2):321-339
Theoretical and Applied Climatology - The multiple downscaled scenario products allow us to assess the uncertainty of the variations of precipitation and temperature in the current and future... 相似文献
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Hicham Si Mhamdi Mohammed Raji Soufiane Maimouni Mostafa Oukassou 《Arabian Journal of Geosciences》2017,10(5):125
The Paleozoic massif of Tichka in the southern part of the Western High Atlas of Morocco constitutes a structural transition between the Meseta and the Anti-Atlas domains. It was affected by a complex network of fractures noticeable at different scales. Using Landsat ETM+ imagery permits detecting the main fracture directions. Various techniques of lineament’s extraction were applied, including the colored compositions, spectral band ratios, and directional filters applied to the principal component analysis. Lineament’s extraction is based on visual interpretation and completed by field observations. The resulted map allows recognizing at least four trending fracture system, with average N-S, NE-SW, E-W, and NW-SE orientations. The surrounding rocks of the granitic massif show a high fracture density. Tectonic indicators show that this massif is initially affected by NW-SE Variscan tectonic extension, followed by NW-SE Variscan compression. This regime is being maintained until the late Variscan period corresponding to the relaxation of the NW-SE major Variscan stress. A clockwise rotation of the latter stress, which became N-S to NNE-SSW, related to the late Variscan deformation, is responsible for reworking preexisting faults. 相似文献
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In the last few decades, several integrated methods for marine sediment quality evaluation have been developed and applied to many coastal sites. This paper describes the development of a general integrated method based on the determination of organic and inorganic sediment contamination, lethal and sublethal toxicity assessments, in situ benthonic community structure alteration and bioaccumulation of contaminants. The proposed method was applied to sediments from Southern Spain's Atlantic coast where six rivers (Guadiana, Carreras, Piedras, Tinto, Odiel and Guadalquivir) drain pollutants from various anthropogenic sources. A series of experiments was conducted to determine the characteristics of the sediments: granulometry, organic matter content, etc. (1); metal contamination of sediments and Chamelea gallina (bivalves widely distributed in the area studied) (2); lethal and sublethal toxicity by a series of biological tests (3); and macrofauna distribution at the 16 stations included in the study (4). Ratio-to-reference values (RTR) calculated for each parameter were used to determine the organic and inorganic contamination indices, the lethal and sublethal toxicity indices, the index of bioavailability of metals in the organisms analyzed and the macrobenthic alteration index. The data were plotted on six-axis plots to describe better the relations between the physical, chemical and biological properties studied. A general integrated sediment quality index (ISQI) was determined and used as an indicator of pollution-induced degradation. The ISQI values summarize the main characteristics of the environmental situation at each sampling point and can be used for purposes of comparison. 相似文献