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AbstractThis article analyzes the new Francophonie of Manitoba. The author, unlike Statistics Canada, uses variables other than “French as the mother tongue” to determine the statistical profile of Francophone newcomers. In the same vein, it highlights the characteristics of a redefined Francophone community in Manitoba in the year 2000 and its new make-up after a new wave of immigration of visible minorities coming mainly from Africa.

AbstractThe present work proposes a learning classification method to identify the functional states of a coagulation process for the treatment of surface water and production of drinking water. Supervisory control and diagnosis were performed using the LAMDA (Learning Algorithm for Multivariate Data Analysis) classification technique. This expert learning method involves the processing and aggregation of all information stemming from an environmental process, and it allows the incorporation of the user's knowledge. The study shows that it is possible to refine the diagnosis by taking into account the information obtained from common sensors (e.g., temperature, suspended solids, pH, conductivity, dissolved oxygen) together with the predicted coagulant dosage, as computed with an intelligent software sensor developed previously. The Rocade drinking water plant located at Marrakech, Morocco was chosen to test the method.

Keywords: Procédé de coagulation, classification, apprentissage supervisé, apprentissage non supervisé, reconnaissance de formes, logique floue, Coagulation process, classification, supervised learning, unsupervised learning, pattern recognition, fuzzy logic

The extent and rates of alluvial deposit and dam siltation caused by sediment deposition from Maghreb streams have prompted a number of attempts to quantify and explain the complex mechanisms of suspended sediment transport. In Algeria, a country with scarce water resources, deposition of sediments in dams is estimated to average 20 million m3 /year, which contributes to a 0.3 % yearly loss of storage capacity from a total capacity estimated at 6.2 billion m3.Of interest in this context are suspended sediment loads in Mediterranean Algeria's Mouilah River, on which is built the Hammam Boughrara, a 117 million-m3 capacity dam put into service in 1998.The Mouilah River basin, situated in northwest Algeria, covers a 2650-km2 area and has a 230-km perimeter (Table I).The Mouilah runs along 124 km, rising at an altitude of 1250 m in Algeria then flowing into Morocco. It is ephemeral; perennial flow sets in near Oujda (Morocco), below which it re-enters Algeria near Maghnia (Figure 1).The study zone is characterized by a semi-arid climate. From 1977 to 1993, annual mean temperature was 16.7 °C. Rainfall was relatively scarce and unequally distributed throughout the year, with an inter-annual average of 300 mm over the same period (Figure 2).Analysis of hydrological dataThe study used instantaneous water discharge values (m3/s) measured at the mouth of the Mouilah from September 1977 to August 1993 (results calculated and furnished by the National Agency of Hydric Resources [ANRH]). For measured values, suspended loads (g/l) were evaluated using samples taken from the river: total suspended loads were calculated as the product of these concentrations and water discharge. The number of samples was adapted to the hydrological regime: They were taken every other day or, during flood periods, as frequently as quarter-hourly.Analysis of the instantaneous discharges showed that suspended loads were related to discharge by a power law (Figure 3).To study the responses of the basin over the hydrological year, we grouped the results - 16 years' worth of data - according to season, and analysed the relationship between liquid discharge and suspended sediment load (Table II). Graphical analysis of Figure 4 reveals that autumn and the spring are distinguished by strong river discharges leading to important transport of solids. The maximum flow of solids was about 104 000 kg/s, resulting from a water discharge of 1880 m3/s in November 1986. By contrast, winter and summer discharges were much smaller; values did not exceed 220 m3/s in winter and 83 m3/s in summer.After the dry season, the first rains of autumn encounter dry, hard and barely erodible soil. The response of the basin in terms of suspended-solids generation is therefore very small. It is the heavy rains of October and November that remove large quantities of solids transportable by streams.After the very dry and cool winter and a succession of freezes and thaws, spring rains fall on poorer soil, leading to relatively high loads, though still lesser than those of autumn.Summer is marked by very dispersed values encompassing the smallest discharges of the year and some relatively high suspended loads associated with low discharges, the latter arising from seasonal storms.In summary, stream discharge is very variable throughout the hydrological year. Suspended sediment transport in the Mouilah River basin occurs principally during flood periods. We distinguished two periods of active erosion, one in autumn and another, lesser period in spring.Annual contributions An annual balance sheet of solid and liquid contributions shows that these two parameters vary regularly and as a function of rainfall (Figure 5). Annual liquid contributions from 1977 to 1993 were evaluated at 48.7 million m3, which corresponds to a mean flood depth of 18.4 mm, and a low flow coefficient of 6 %. Due to very dispersed and extreme values and variability, rainfall-discharge relations are varied. This leads to inter-annual irregularity for flood depths: consequently, a relationship with annual rainfalls (Figure 6) was difficult to establish. However, we noted a tendency of the form: LE=0.0009P1.69 (R=0.74).The annual mean contribution of suspended sediment at the mouth of the river was estimated at 335 000 tons, which corresponds to a soil erosion rate of 126 tons/km2/year. This value is moderate compared to other basins of the region, such as the Mazafran (Algiers) and Isser (Lakhdaria) river basins, where erosion rates are about 1610 and 2300 tons/km2/year, respectively (Table III).The inter-annual solid and liquid contributions contrast markedly. Indeed, for liquid contributions, the first and third quartiles are 21.8 and 64.7 million m3, respectively, which shows that 25 % of the annual moduli representing humid years were three times more important than those representing dry years (Figure 7). Furthermore, in annual loads expressed as stream turbidity, variation between the temperate and arid reaches of the stream is apparent.Figure 8 shows that the highest annual liquid contribution, 117.8 million m3, was recorded during the year 1979-80, and generated a solid contribution of 670 000 tons. This liquid contribution is higher than that of 1986-87, evaluated at 106.4 million m3, which carried 2.69 million tons - an erosion rate of more than 1000 tons/km2/year.

Keywords: Pluie, débit liquide, débit solide en suspension, dégradation spécifique, bassin versant, Oued Mouilah, Algérie, Rainfall, discharge, erosion, suspended load, erosion rate, Mouilah, Algeria

In the wastewater stabilization pond, the growth of the microalgae depends on several factors such as temperature, light and nutriments. In addition to these factors, the presence of the organic matter has great influence on the development in such system. In the aim to study the dynamic of the microalgae in the wastewater stabilization pond of Ouarzazate city (south of Morocco) and possibly its modelling, the determination of the growth parameters (µmax, Iopt and b) has been carried out according to the model of PEETERS and EILERS (1978). Indeed, Micractinium pusillum, a Chlorococcal green algae developing in the experimental wastewater stabilization pond of Ouarzazate city has been isolated and cultured under controlled conditions of light and temperature on synthetic medium (DAUTA, 1982) enriched in nitrogen and phosphorus.In autotrophic conditions, application of the PEETERS and EILERS model to the growth of Micractinium pusillum, resulted in the determination of the parameters: µmax (0,58 day-1), Iopt (182 µE·m-z·s-1) and b (0,1) using the maximal growth temperature of 35°C. In mixotrophic conditions under the same temperature, these parameters were respectively 0,85 day-1, 150 µE·m-z ·s-1 and 1. According to the trophic mode, the growth of Micractinium pusillum revealed a variation of the parameters µmax, Iopt and b. The mixotrophic growth, probable behaviour in the wastewater stabilization pond, has induced particularly the elevation of the growth rate and the coefficient b. Also, this study showed that light intensity has varied effects on the growth of microalgae in the two trophic modes.

Keywords: Micractinium pusillum, croissance, autotrophie, mixotrophie, lumière, température, Micractinium pusillum, growth, autotrophic, mixotrophic, light, temperature

The fate of nitrogen (N) and phosphorus (P) was studied in a high-rate algal pond (HRAP) during the start-up period and under steady-state conditions. The HRAP was first used by Oswald and co-workers in Berkeley (California, USA) in the late 1950s for wastewater treatment with algae collection as a by-product for Single Cell Protein production. The HRAP consisted of a raceway shaped, shallow pond (less than 0.50 m deep) equipped with a continuous and gentle mixing device (paddle wheel) generally operated at 8 rpm. The paddle wheel is not used for aeration purposes.In this study, the HRAP is included in a wastewater treatment plant aimed at producing good quality effluent for agriculture reuse purposes. The treatment plant includes three components with the HRAP placed in the middle of the pond train. Up-stream, there is a two-phase anaerobic reactor (TAR) and downstream, two maturation ponds in series. Assigned removal tasks for the plant components are as follows: i) organic matter, suspended solids and helminth eggs for the TAR; ii) N and P for the HRAP; and iii) fecal coliforms for the two maturation ponds. The capacity of the plant is 1,500 inhabitants (70 m3/day), total hydraulic retention time is 8 days and the total occupied area is 1,500 m2 including walkways and other facilities. The plant was constructed in December 1996 and has been continuously operated since that time.The present paper focuses on the fate of N and P in the HRAP in order to evaluate its performance and to shed light on the mechanisms behind N and P removal, with the ultimate goal to improve surface and groundwater protection from pollution by wastewater nutrients. Under steady-state conditions and when we consider the soluble part of N and P taken up by the algal cells together with that lost (either by stripping or chemical precipitation), the total removal averaged 70% for N and 40% for P. Such important removal must be highlighted especially because the system relies on solar energy with no electromechanical aeration, is cheap to construct and easy to operate and maintain.To understand the mechanisms behind such a performance and also to gain experience for the process start-up and for rational operation and maintenance of future plants, an in-depth analysis on the fate of N and P was done based on the four-year follow up data. Total N losses reached an average of 34.5% in the start-up period and 24.5% under steady-state conditions, whereas N assimilated by the algae represented 32 and 43.5%, respectively. Particulate organic nitrogen (PON) accumulated in the bottom of the unit did undergo rapid mineralization under steady-state conditions. Mechanisms involved in N losses might be attributed to settling of PONr and, to much lesser extent, NH3 volatilization in the cold season, whereas the latter mechanism might occur primarily in the hot season. The rates of mineralization of HRAP sediment were estimated to be 12.4 and 1.3 kg of N ha-1 d-1 respectively for the hot and the cold season.On average, total P losses in the HRAP reach 27% in the start-up period and only 17.5 % under steady-state conditions, whereas algae assimilation represented 25 and 17.5% respectively. Under steady-state conditions, algae uptake (54%) and chemical precipitation (46%) were found to be the main mechanisms for P removal in the HRAP.

Keywords: Eaux usées, épuration, CAHR, azote, phosphore, volatilisation de NH3, biomasse algale, Wastewater, treatment, HRAP, nitrogen, phosphorus-stripping, algal biomass

This article proposes to shed new light on East-West relations from the logic of modern globalization. The essays of the Moroccan sociologist Fatima Mernissi generate such a debate by problematizing the notion of barbarism in the context of what is commonly referred to as “the cultures of exchange”. The questioning of barbarism is inextricably linked to the questioning of the transmission of Islamic religious knowledge by male experts mainly. Historicism points to the problematic radicality of modern ideologies. To counter and defeat the dangers of a univocal reading (or intergrist reading) of Islamic literature, Mernissi proposes a humanistic feminization of the interpretation of the inherited knowledge on Islam, a hermeneutical challenge tied into a dynamic of deconstructing (and reconstructing) such knowledge. If barbarism lies in transmission, civilization lies in the democratization of the reading of knowledge.

L'objectif de cette recherche est l'amélioration des connaissances sur les relations entre l'analphabétisme et l'éducation, d'une part, et la pauvreté (sous-développement) de l'autre, et sur l'impact de l'éducation sur la culture et le développement local rural. Dans le domaine de ces relations, le présent travail de recherche est mené selon la démarche inductive. Toutefois, nous ferons parfois appel aux principes de la démarche déductive. Pour acquérir un savoir à partir des points de vue des acteurs sur le terrain concret au Maroc, dans la région naturelle du Rif d'où nous sommes originaires, sur les phénomènes non suffisamment explorés à ce jour, avant d'aller sur le terrain, nous avons d'abord délimité le foyer de la recherche. La formulation du problème de recherche débute avec l'identifi cation …