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Eutrophication is one of the most important water quality problems in lakes. Due to the effects of excessive external inputs of nutrients (phosphorus and nitrogen), compounded with unfavorable climatic and hydrologic conditions, the lake undergoes major changes that involve both the physical-chemical properties of water and the aquatic communities living there. There have been many studies on lake ecosystems and their evolution (HENRY et al., 1984; AFDALI, 1993; HARRAK, 1991; LOUDIKI et al., 1994; SBIYYAA, 1998, MOUHRI et al., 1999). These studies relate especially to the role of nutrients (nitrogen and phosphorus mainly) in the evolution of lakes. The influence of climatic and hydrologic conditions on the structure and dynamics of these ecosystems has been often underestimated. Indeed, there are few studies on the relationship between climatic conditions and the trophic status of aquatic ecosystems.The aim of this paper is to study the behavior of the physical-chemical qualities of water in lake Mansour Eddahbi (Ouarzazate, Morocco) and its trophic status under severe climatic conditions, especially during the very dry hydrological year 1998/99. The Ouarzazate region is characterized by an arid continental climate with very hot summers and cold winters. Due to both great evaporation and increasing demand for water for irrigation, the water levels of the reservoir has been reduced by 14 m and its storage capacity has been considerably reduced. The approach used was to assess water quality in a station at the deepest area of the lake during the hydrological year 1998/99. Sampling was undertaken monthly and different parameters were analyzed including temperature, pH, total suspended solids (TSS), salinity, dissolved oxygen (DO), chlorophyll a, phosphorus (TP and PO43-), and nitrogen (TNK, NO3 - and NH4 +).The results of this study demonstrated important seasonal variations of water temperature in the lake. Temperature varied from 9.5°C in the winter to as high as 28.5°C in the summer. Based on this parameter, the reservoir could be classified as a monomictic hot lake with one mixing period occurring in winter. In the entire water column, the pH values were slightly alkaline and oscillated between 7.8 and 8.5 at the surface and 7.4 to 8.2 at the bottom of the lake. This reflects a well-buffered system with moderate benthic decomposition activity. The decrease in water volume by evaporation and intensive use for irrigation resulted in an increase in water salinity. These two parameters presented a significant correlation (r2 =0.60 for n=13 and p<0.05). A decrease in dissolved oxygen from 7.3 mg O2 /l at the surface to 0 mg O2 /l at the bottom of the lake occurred during summer stratification. However, water of the lake reservoir was well oxygenated during preceding years (concentration of dissolved oxygen oscillated between 2 and 11 mg/l (ONEP/BRL, 1998)). Concentrations of chlorophyll a in the euphotic zone (8 m depth) were very important and varied from 12 µg/L (August 1998) to 49 µg/L (September 1999) with an average of 25 µg/L. Based on the chlorophyll a value, the lake Mansour Eddahbi could be classified as eutrophic.The lake has become shallower and the thermocline, beginning at 12 m below the surface, has moved closer to the deeper layers where exchange between sediments and the water column is important. These exchanges between the two compartments of the lake contributed to enrichment of the water column in summer, creating an internal nutrient load. During the hot period when the lake was stratified, there was a large loss of nitrogen from the system. During the mixing period, nitrates were present at substantial concentrations in the deeper regions, but in summer nitrates were consumed rapidly in the surface layer, leading to a limitation on phytoplankton growth in this period. This same phenomenon was also noticed by HENRY et al. (1984). Furthermore, these losses of nitrogen induce a strong reduction in the N/P ratio during this period.Orthophosphate concentrations decrease from the bottom layers to the surface, with almost total impoverishment in the upper strata. This impoverishment reaches 10 m during the summer period and these values are often limiting for the phytoplankton production. The correlation obtained between orthophosphate concentrations and chlorophyll a was significant, especially in summer (r2 =0.79 for n=13 and p<0.05).Nutrient exchange at the water and sediment interface was favoured by the anoxic conditions at the lake bottom that prevailed during the eight months of stratification. The release of these substances can alone, without external contributions, maintain important primary production. This was confirmed by the importance of phytoplankton development compared to the preceding years. The algae production seemed to be enhanced, even if the reported N/P ratio was not optimal, particularly during the period of stratification and had no significant correlation with chlorophyll a content (r2 =0.19, n=13 and p<0.05). This important production appeared to be the result of an internal enrichment of the lake in nutrients coming from the sediment. According to nitrogen (0.2 mg/L) and phosphorus values (0.02 mg/L), the lake could be classified as hypereutrophic whereas two years earlier it was considered mesotrophic (ONEP/BRL, 1998). This work shows clearly that the severe climate conditions during the hydrological year 1998/99 contributed to a rapid degradation of the trophic status of this lake. It changed from a mesotrophic to a hypereutrophic state, resulting from an important enrichment in nutrients and the consequent algal production.

Keywords: Lac, Climat aride, État trophique, Qualité de l'eau, Minéralisation, Nutriments, Azote, Phosphore, Lake, Arid climate, Trophic status, Water quality, Salinity, Nutrients, Nitrogen, Phosphorus

The Paris Principles on the Status and Functioning of National Institutions for the Protection and Promotion of Human Rights have come to embody an evolution that has sprung up in national law for several decades. They mark the growing institutionalization of human rights in domestic law and underline the central role of national institutions as indispensable relays for international human rights law in order to be fully respected in national laws. Indeed, the state and its organs are the first recipients of human rights standards and the responsibility to protect them is their primary responsibility. The Arab States, especially since 2011, when the Arab Spring began, are an interesting case study of the role of the Paris Principles in the institutionalization of human rights. After long decades of dictatorship confining international human rights law from a broadly formal perspective, the political and social upheavals that the region has experienced in recent years offer hope for improvements in the articulation of national laws with international human rights law and better protection of these rights in which national institutions could play a more active role. The study aims to describe the generalization movement of these institutions in the Arab world, to study the interactions they have with the internal and international institutional fabric before concluding with an evaluation of their effectiveness in the protection and promotion of human rights in this part of the world.

Through this text, we aim to better understand the expression of subjective, ethical and aesthetic experiences of Sufi women living in Montreal, all while identifying the dynamic interactions between the key concepts they foreground. These concepts seem to form a conceptual constellation that, for these women, makes up a grid of interpretation of the world and a guide on how to act in this world. Would such a hermeneutic action, which fuses conceptualization and the experiential in the day-to-day, participate both in the construction of the self and a co-existence where difference and otherness would fall under the scope of theophany and sanctity? This is the key question we ask here. We essentially rely on qualitative data. The analysis of this data allows us to see that unpardonable atrocities, perpetrated in the world in the name of Islam by a small, violent, radical minority, organized into murderous militants and reticent to any form of otherness, should not obscure the existence of an Islam of co-existence where the Other is subject to ennoblement.

Keywords: Soufisme, femmes, islam, religiosité, vivre-ensemble, concepts expérientiels, technologie de soi, herméneutique-action, éthique, esthétique, Canada, Maroc, Sufism, women, Islam, religiosity, co-existence, experiential concepts, technology of the self, hermeneutics action, ethics, aesthetics, Canada, Morocco

The purification technique of wastewater by High Rate Algal Ponds (HRAP) is distinguished from the traditional lagoon by a shorter residence time, a shallow depth and constant mechanical agitation. This agitation can be done by a water jet, a paddle wheel, or an air lift. A comparison of the hydrodynamic behaviour of the two agitation systems most often used for wastewater treatment systems similar to High Rate Algal Ponds (air lift and paddle wheel) was undertaken. Power energy consumed by these two agitation systems is compared for typical effluent circulation rates usually encountered in this type of wastewater treatment process. The purification performances for both agitation systems are also analyzed.The results showed that energy consumption using the air lift is about 3 to 5 times less costly than the paddle wheel. This advantage is also confirmed in terms of treatment efficiency since better removal of nitrogen and phosphorus using the air lift system is observed. This study shows that good functioning of the High Rate Algal Ponds can be obtained using the air lift as the agitation system.

Keywords: chenal algal à haut rendement, diffuseur d'air (air lift), roue à aube, hydrodynamique, efficacité épuratoire, high rate algal ponds, agitation, air lift, paddle wheel, hydrodynamics, purification efficiency

AbstractThis article aims at the indirect estimation of the transmissivity (T, m2/s) of the aquifer of Haouz (6,000 km2) in Morocco, using the transverse resistance (R, Ωm2). This aquifer consists of a complex succession of lenticular layers, argilo-marly or formed of coarse elements, of plio-quaternary age, lying on a marly substratum of miocene age. A significant database of the values of transmissivity (≈500) and transverse resistance (≈2,500) was compiled. A research was then carried out to select the pairs (Ti, Ri) characterizing the same volume of aquifer. Two cases of transverse resistance are considered: 1) transverse resistance of the mio-plio-quaternary unit (RA); 2) transverse resistance of the permeable coarse lenses only (RB). The best regression, of geometrical form, is obtained between the transmissivity and the transverse resistance of the permeable coarse lenses. This regression is significantly improved when the values (T; RB) of a given pair are brought back to the same level of the water table, after correction of the transmissivity according to the variations of the water table. The indirect estimate of the field of transmissivity of the aquifer is then carried out at a regional scale using the regression equation previously established. The estimated field of transmissivity is validated through the comparison of its statistical properties (central tendency, dispersion, distribution law) to those of the sample of the values of transmissivity measured by pumping tests.

Keywords: transmissivité, résistance transversale, aquifère hétérogène, prospection électrique, distribution lognormale, régressions statistiques, Haouz de Marrakech, transmissivity, transverse resistance, heterogeneous aquifer, lognormal distribution, statistical relationships, Haouz of Marrakech

The study of the flood transport, plankton and the stomach contents of Cladoceran species and some planktivorous and omnivorous fish of the reservoir-lake Bin El Ouidane has allowed to extract the following conclusions:- flood transport of dissolved and suspended matters during the period 1995-1997 has a net influence on the seasonal dynamics of the zooplancton via changes in the dynamics of the phytoplanktonic populations;- during the same period, the peak of zooplanktonic biomass appeared generally just after spring and summer phytoplanktonic peaks showing the importance of the herbivorous zooplankton in the food chain;- the study of algal stomach contents of Cladocerans Daphnia longispina, Daphnia lumholtzi, Diaphanosoma brachyurum, Ceriodaphnia dubia, Ceriodaphnia reticulata and Bosmina longirostris showed that all species are herbivorous filter-feeders that adopt a variable diet behavior linked to the availability of the phytoplankton in the lake, to their age and biotic and abiotic characteristics of the ecosystem;- the preliminary study of the stomach contents of three omnivorous and herbivorous fish Tinca tinca, Eupomotis gibbosus and Cyprinus carpio species showed also that their food spectre was clearly dominated by the plankton. The animal fraction in their digestive tube was represented by large Cladoceran species and Chironomes showing the importance of these fish, essentially planktivorous, in the regulation of planktonic populations in the reservoir-lake Bin El Ouidane.

Keywords: Lac-réservoir, phytoplancton, zooplancton, poissons, régime alimentaire, Reservoir-lake, phytoplankton, zooplankton, fish, diet

AbstractWater supply and sanitation services (WSSS) face numerous institutional, technical and financial constraints. The expectations of customers and, more broadly, the social and environmental dimensions also determine the supply of services. The objective of this article is to analyze the economic situation with the aim of improving the performance of WSSS in Algeria, using the example of the Souk-Ahras Department. This research includes an empirical analysis (technical and financial) of the management of WSSS, by analyzing data collected from the WSSS management services of the department of Souk-Ahras. According to our results, drinking water and sanitation tariffs do not cover operating costs, rehabilitation and renewal investment costs and tariff grids give large consumers the benefit of the "solidarity" tariffs for the first billing periods.

Keywords: performance économique, services d'eau potable et d'assainissement, Souk-Ahras, Algérie, economic performance, water supply and sanitation services, Souk-Ahras, Algeria

La présente thèse porte sur la progression des femmes dans des postes de direction dans l'administration publique en Tunisie et au Maroc. La problématique de départ vise à identifier comment les femmes parviennent à accéder à des postes de décision au sein de l'administration publique en Tunisie et au Maroc dans un contexte où elles sont toujours sous-représentées. Les considérations liées à l'égalité entre les sexes, aux politiques mises de l'avant par les organismes internationaux, à la participation des femmes à la gouvernance, à l'accroissement de la présence des femmes dans différents domaines d'activités et aux réalités vécues par les femmes en Tunisie et au Maroc constituent le point de départ de cette recherche. En tenant compte des diverses perspectives théoriques de recherche qui présentent …