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Mining activity started in Morocco in the 9th century. Several metals were prospected for but lead was preferentially mined owing to its silver content. The mining history of Morocco can thus be summarized by the history of lead prospecting within the country. Strong mining activity resumed in the 1970s and has been maintained since that time, with lead still being the main metal produced. In 1980 its production reached about 170,000 tons of concentrated lead, which corresponds to 3.5% of the world's production (Wadjinni, 1998). In 1975, the Aouli and Mibladen mines were depleted and in 1986 the Zaida mine was closed. This resulted in large mining districts being abandoned with their mining and metallurgic equipment left on the surface together with all the accompanying waste materials, including tailings. This has created an important source of contamination, progressively releasing trace elements into the environment.The goal of the present study was to characterize the spatial distribution of the heavy metals (Cd, Cu, Pb and Zn) released from the Aouli mine into the Moulouya River. This river, which drains the Aouli, Mibladen and Zaida mines, is a good example of the pollution impact arising from abandoned mining sites. In order to understand the behaviour and the fate of these metals within the only permanent river in this region, contamination levels were measured in three components of this river, namely: water, suspended solids and sediments.Due to the presence of mountainous areas (Rif, Middle and High Atlas), the Moulouya River basin is characterized by variable relief. The river basin also contains high plateaus (the Horsts chain) and low plains (the Missour-Outat El Haj and the Taourirte-Guercif basins). This large area can thus be subdivided into three zones designated by the upper, middle and lower Moulouya basins (Fig.1).The Upper Moulouya basin corresponds to the southwest region of the Oranaise Meseta that is bounded by the High Atlas on the Southeast and by the Middle Atlas on the Northwest. They are composed of two separate Paleozoic massifs (the Bou-Mia and the Aouli). The Paleozoic substratum that outcrops into these massifs consist of pelletic and quartzitic rocks intruded by Hecynian granites and overlain non-uniformly by a Mesozoic cover consisting of Triassic evaporite/clastics and Jurassic and Cretaceous carbonates and shales.The Middle Moulouya basin is separated from the Lower Moulouya basin to the North by the Yacoubat paleo-high that corresponds to an East-West oriented topographic bulge where the river narrows considerably. The outcropped rock consists mainly of Jurassic carbonates and marls, Cretaceous carbonates, marls and sandstones and Tertiary and Quaternary conglomerates, marls and gypsum.The Lower Moulouya basin corresponds to a vast plain extending from the Yacoubat High in the South to the Jbel Mazgout and the Beni-Snassen in the North. This area is underlain by Paleozoic granites, Triassic marls and basalts, Jurassic and Cretaceous carbonates, marls and sandstones and Tertiary and Quaternary conglomerates, marls and carbonates. The Moulouya river basin is characterised by a variable climate, which changes from a Mediterranean type in its low portion to a sub-Saharian type in its median portion and to a continental type at higher elevations.Sampling was carried out during low water level periods. In order to obtain good representative sampling, three samples were taken from each station and were used to measure metal contaminant concentrations in water, suspended solids and sediments. The sediment samples were taken from approximately 5 cm below the surface within the river plain, which is characterized by fine-grained low-energy organic matter-rich sediments.We defined a certain number of pollution parameters within the Moulouya basin, based on the samples taken from eight representative sites. The areal distribution of metal concentrations in water and in suspended solids shows the existence of two main contamination sources: the abandoned Aouli mine and urban waters. Dissolved Zn concentrations varied from 3 to 30 µg·L-1 and the two highest concentrations occurred at station 3 near the Aouli mine and at station 8 located in oued Za near the town of Taourirt (Table 1). Cadmium, Cu and Pb concentrations showed similar trends with high concentrations occurring at stations S3 and S8 for Cd and Cu and at stations S3 and S5 for Pb (Fig. 2). These high levels were explained by the effect of Aouli mine for station S3, the Tindit mineralization area for station S5 and urban waters from Taourirt for station S8.Metal concentrations in sediments reflect the downstream attenuation of the Aouli mine effect (station S3). In fact this station is characterized by high metal concentrations, especially Pb and Zn and to a lesser degree Cd and Cu. For Cu, its concentration in sediments was found to be similar to its concentration in the suspended solids. This is explained by the precipitation of Cu(II) as oxides and hydroxides. The areal distribution of Pb and Cd was similar to that of Zn, suggesting that the Aouli mine is also a source of these metals.By comparing concentration ratios of different metals with respect to that of Zn, we found that all these ratios remain constant downstream from the Aouli mine, with the exception of the Pb/Zn ratio, which increased at station S3 (Fig. 3). This distribution indicates an effect of the Aouli mine (station S3) and to a lesser degree of the Tindit area (station S4). No notable effect of the Moulouya tributaries on the concentrations of metals was detected.

Keywords: Oued Moulouya, contamination, métaux lourds, sédiments, Moulouya River, heavy metals, sediments, mine water

Children with special needs are much more predisposed to have difficulties with school integration than the average people. In addition, they tend not to be diagnosed by the professionals who supervise them. In Morocco, the evaluation of these individuals is currently considered as the main weak point. This article has two objectives: the adaptation of the scale (of Quebec) of adaptive behavior (-school version) to the Moroccan school context and an essay of social validation from the parents and teachers. It appears that the right tool is interesting, answering to the demand of underworld and receiving a positive reception. It can give a working basis, informing educational teams on the skills acquired by each child and helps to develop an individualized educational program.

The supply of Casablanca city with drinking water is insured mainly by waters from the storage reservoir Tit Mellil, which is fed by the treated waters coming from the Sidi Mohamed Ben Abdellah dam. These waters are often affected by eutrophisation, with the attendant proliferation of cyanobacteria, which exercise a negative impact of the production of drinking water. In fact, the physico-chemical analyses carried out on both raw and treated waters have allowed us to make a diagnosis. This diagnosis reveals that the characteristics of the raw waters favour the proliferation of cyanobacteria. Many types of the cyanobacteria are identified, including Microcystis and Oscillatoria, which are considered to be the most toxic as well as the producers of microcystins (MC). We used a colorimetric protein phosphatase inhibition assay for an evaluation of dissolved and intracellular microcystin levels in raw and treated water with a detection limit of 1 ng•L-1. Tests done on treated water at the entrance of the storage reservoir reveal that dissolved MC are present in all the samples taken during the summer-autumn periods from 2006 to 2008. Their rates do not exceed 0.075 µg equivalent to MC-LR•L-1. Though these values are positive, they are below the threshold recommended by the World Health Organisation, which is 1 µg equivalent to MC-LR•L-1 of water. The amounts of microcystins in the treated waters are clearly less than those in the raw waters for the same periods. These values reached a maximum of 1.1 µg equivalent to MC-LR•L-1 in October 2006. On the other hand, an evaluation of the amounts of dissolved microcystins at the exit of the treated water from the storage reservoir revealed a clear decrease of microcystins concentration; this is probably due to the effects of the chlorination that had been applied to these waters.

Keywords: eau potable, cyanobactéries, microcystines, protéine phosphatase 2A, chloration, drinking water, cyanobacteria, microcystins, protein phosphatases 2A, chlorination

This text presents a description of the plant world of an oasis in pre-Saharan Morocco (Souss region) by emphasizing the daily presence of elderly women from very modest backgrounds, who come daily to weed and collect spontaneous plants. These women have a special relationship with the latter and transpose their nourishing, prophylactic, therapeutic or magical powers to the oasis community as a whole. But the question arises of what will happen to this field of relationships, so integrated into fertility cycles, in the wake of the structural transformations and modernization projects currently under way in oasis areas. These projects, while supporting environmentalist objectives, affirm a modality of qualification of the soil and its exploitation that tends to eclipse the presence of these women, neglecting at the same time the whole cosmological background on which their attentive gestures draw, and the sensate permeability of the oasis plant universe of which they are the custodians.

Keywords: Breviglieri, oasis, femme, végétal, écologie, soin, atmosphère, vie, communs, Breviglieri, oasis, woman, vegetal, ecology, care, atmosphere, life, commons, Breviglieri, oasis, mujer, vegetal, ecología, care, atmósfera, vida, comunes

The high plains of Lebanon are subject to water erosion which tends to strip its soils and threaten its agricultural activities. The combined effect of anthropogenic actions (cultural management, deforestation, overgrazing) and natural factors (climatic aggressiveness, steep slopes, soil), weakens the soil and threatens agricultural parcels by depositing sediments. Mhaydssé is a village concerned by this problem and its representative of the natural and anthropogenic conditions of the Békaa's southeast. The study uses GIS and the Universal Earth Loss Equation (USLE). To replace the intensity of precipitation, the aggressiveness index was calculated from the equation of Renard and Freimund. Five soil types were sampled, for which the soil granulometry was analyzed in five classes. The topography (slope), the vegetation cover and the anti-erosion practices are the other factors that have been quantified. Of the 1800 hectares of the study area, the average loss of land is 46 t / ha / year. This high value comes from a high spatial heterogeneity. The barren slopes are subject to rates above 300 t /ha /yr, while the bottom of the plain is practically untouched. Large spatial differences over small distances confirm the thoroughness of an accurate analysis of soil texture.

Keywords: érosion hydrique, USLE, SIG, Békaa, Liban, soil erosion, USLE, GIS, Békaa, Lebanon