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Osmotic adjustment, photosynthetic pigments and changes in antioxidant enzyme activities were evaluated in ten durum wheat (Triticum durum) genotypes under water stress conditions. The wheat seedlings germinated in hydroponic conditions in a growth chamber. Water deficit was performed at the fourth and fifth leaf stages using a polyethylene glycol (PEG 6000) solution (-0.49 MPa). Osmotic potential as well as total chlorophyll (Chl a+b) and carotenoid (Car) contents were investigated. Electrophoretic analyses were performed for three antioxidant enzymes: superoxide dismutase (SOD), guaiacol peroxidase (GPOX) and catalase (CAT) using native polyacrylamide gel electrophoresis (PAGE). The results obtained show a reduction in leaf osmotic potential and a decrease in Chl a+b and Car contents under water stress conditions. However, there are significant differences between the genotypes studied in their response to the treatment. PAGE showed an increased intensity in the enzymes studied and the appearance of additional isoforms, including one CAT and three SOD, under stress conditions. These differences in water stress response could be useful and reliable indices for the selection of tolerant durum wheat genotypes.

Keywords: accumulation d'osmolytes, chlorophylles, déficit hydrique, isozymes, peroxydation lipidique, stress oxydatif, chlorophylls, isozymes, lipid peroxidation, osmolyte accumulation, oxidative stress, water deficit

Investigating gender relations in Algeria brought the author back to the place where she had spent her childhood, on the outskirts of Algiers, between 2014 and 2016. On this familiar ground, she did an ethnographic study on the movement of female bodies when leaving domestic spaces. Sharing gender constraints with the subjects of her study in the domestic space, as well as experiencing harassment outside the domestic spaces, set the conditions for her involvement as a researcher. This field practice allowed her to co-produce a situated, embodied knowledge that rendered forms of agency and of spatial and social resistance intelligible.

Keywords: Savoir situé, agentivité, motilité, vulnérabilité, implication, Situated knowledge, agency, movement, vulnerability, implication

This study aims to investigate how a specialized body of knowledge – andragogy – can contribute to the development of professional identity for adult education teachers. It focuses on the official discourse included in governmental, administrative and regulatory documents for teachers and its potential influence for understanding the specifics of teaching practice. This document analysis sheds light on the possibility of grasping andragogical concepts through official documents while signaling the presence of ambiguity which can lead to difficulties in the development of a clear professional identity.

Keywords: Andragogie, discours, identité professionnelle, formation générale des adultes, éducation des adultes, Andragogy, educational science, professional identity, adult basic education, adult education, Andragogía, discurso, identidad profesional, formación general de adultos, educación de adultos

This work aims at the determination of favourable areas for the recharge of the Bonoua aquifer, using a cartographic approach and a Geographic Information System (GIS). The determination of these potential recharge areas of the aquifer required the integration of spatial information related to different parameters regulating the recharge, which are represented by thematic maps. A new classification has been done with a weighting of these parameters according to their degree of involvement in the recharge process, using a multicriterion analysis such as the Analytical Hierarchy Process (AHP) of Saaty. In order to establish the map of potential recharge areas for the Bonoua aquifer, the weighting parameters were incorporated in the GIS. Analysis of the resulting map revealed five classes, included one class of better recharge covering 66% of the studied area. This dominant class is located at the central part of the aquifer, especially in the Terminal Continental, which is largely composed of coarse sands with relatively shallow slopes, where the land is used by industrial cultures. The areas of low recharge (34% of the studied area) are located at the western and eastern borders of the studied area on hydromorphic soils. This map showing the spatial distribution of the recharge areas could be considered as a decision-making tool, especially for management of the water resource and analysis of groundwater vulnerability. The preferential recharge areas need particular attention from authorities in order to ensure protection of the aquifer.

Keywords: recharge, eau souterraine, analyse multicritère, Bonoua, Côte d'Ivoire, recharge, groundwater, multicriteria analysis, Bonoua, Côte d'Ivoire

Increasing interest in removing natural organic matter (NOM) has lead to the development of new drinking water treatment technologies. Since July 1992, a nanofiltration demonstration plant (2 x 1400 m3 d-1) has been used to treat sandfiltered water from the Oise river. The permeate has been distributed since February 1993 to the 6000 inhabitants of Auvers/Oise in the Paris suburb. The purpose of this paper is to present and discuss some ofthe results obtained over nine months of operation of this full scale plant, particularly yields of NOM removal and consequently the decreasing of chlorine reactivity (chlorine demand, TTIM and TOX formation potentials).Dissolved organic carbon (DOC) and UV-absorbance were determined using DOC analyser and a spectrophotometer. Biodegradable dissolved organic carbon (BDOC), which represents the biologically assimilable portion of DOC, was determined using the method of JORET et LEVI (1986). Chlorine demand, trihalomethane and total organohalide formation potentials (THMFP and TOXFP) were carried out under the following experimental conditions: applied chlorine dose of 2.5 mg Cl2/mg DOC, pH = 7,5 72 h-contact time and 20°C. Ultrafiltration experiments involved the use ofa laboratory ultrafiltration cell, Total amino-acids were analysed by HPLC after hydrolysis and orthophtaldialdehyde (OPA) derivatization. Aldehyde and ketone determination was based on the method developedby GLAZE et al. (1989) involving pentafluorobenzyl hydroxyl amine (PFBHA) derivatization.Characterization of sand-filtered water (SFW): The sand-frltered water (SFW) upstream of the nanofiItraton membranes has a DOC between 2.4 and 4.l mg l-1, depending on the season (table 1). Its BDOC ranges from 0.7 to l.l mg l-1 C. In fact, a BDOC value higher than 0.3 mg l-1 C has been mentioned by several authors as the limit above which possible bacterial regrowth can take place in the distribution network.The chlorine consumption curves, shown in figure 2 for five sampling campaigns, indicate that the chlorine demand of the SFW can reach 3.4 to 5.2 mg l-1 depending on the season (table 2). The THMFP and the TOXFP are 108-149 ug l-1 and 344-446 ug l-1 Cl- respectively. Note that the ratio of chlorine demand over DOC varies from 1.0 to 1.7 mg Cl2/mg DOC while the THMFP/DOC and TOXFP/DOC ratios present average values of 47.5 ug/mg DOC and 160 ugCl-/mg DOC respectively.The distribution of the SFW (table 3) indicates that the fraction with apparent mo lecular weight Iess than 3 kilodatons contains the major compounds at this stage of the water treatment. This fraction presents the highest chlorine consumption. Specific total amino acids (TAA) analyses demonstrate that TAA represent 3 to 8% of the DOC of the sand-filtered water. The most abundant arnino acids are glycine, aspartic acid, glutamic acid, serine and alanine. The chlorine consumption attributed to these amino acids is evaluated as 1 mg l-1 Cl2, that is to say 1/5 to 1/3 of the SFW chlorine demand. Formaldehyde and acetaldehyde seem to be the major aldehydes present in the SFW with a level of 7 ug l-1 and 20 ug l-1 of formaldehyde and acetaldehyde respectively. They represent only about 0.5 to 0.6 % of the SFW DOC.Characterization of the permeate: The nanofiltration permeate presents a very low NOM level in terms of DOC, BDOC and UV absorbance at 270 nm, that is to say 0.14 to 0.34 mg l-1 C, < 0.1 mg l-1 C and < 0.006 cm-1-l respectively (table 6).The chlorine consumption curves, showt in figure 4 for five sampling campaigns, demonstrate the low permeate reactivity with chlorine. The chlorine demands (table 7) after 72 hours are between 0.12 and 0.32 mg l-1. Moreover chlorine demand/DOC ratios have a value from 0.46 to 0.93 mg Cl2/mg DOC, i.e. half the values measured for SFW. The THMFP and TOXFP (72hours) range from 7 to 11 ug l-1 and 26 to 31 ug l-1 Cl- respectively.Total amino acid (TAA) analyses showed that TAA represent 35 to 60% of the permeate DOC and can account almost entirely for the chlorine consumption. Formaldehyde and acetaldehyde (the major aldehydes analysed) represent 7 to 8% of the permeate DOC.According to the results presented in this paper, nanofiltration appears to be an excellent technolory as a polishing step in surface water treatment. Whereas the level of sand-fïltered water (SFW) DOC varies from 2.4 to 4.1 mg l-1 C (depending on the season), the permeate DOC is consistently lower than 0.3 mg l-1 C. The efficiency of nanofiltration is about 90% for DOC, BDOC and consequently for chlorine demand, THMFP and TOXFP. The high retention of NOM is probably in relation with the percentage (75%) of compounds with apparent molecular weight above 500 daltons in the SFW. In fact the low values of BDOC and chlorine demand justify the use of nanofiltration for the production of a water which represents a very low risk of bacterial regrowth and a low risk of formation of disinfection by product in the network when distributed with a low concentration of residual chlorine.

Keywords: Anofiltration, matière organique naturelle, COD, CODB, organohalogénés, trihalométhanes, acides aminés, Nanofiltration, natural organic matter, DOC, BDOC, organohalides, trihalomethanes, aminoacids

Urban and agricultural development has had a significant impact on the water quality of rivers and lakes around the world. In the last few decades, constructed wetlands have been designed as wastewater treatment systems to prevent water quality deterioration in natural receiving waters. Constructed wetlands are built because they are considered sinks for many pollutants thereby protecting the water quality of downstream ecosystems. The treatment performance of these wetlands is generally assessed using mass balance calculations. However, the retention of metals by constructed wetlands is highly variable and the factors involved are still poorly understood. If wetlands are sinks for metals, the metal content of organisms should be lower downstream than upstream. In this context, organisms can be useful to assess the retention or transformation of metals by wetlands.The objective of this study was to determine whether periphyton and the gastropod Helisoma trivolvis could be used to evaluate the retention of dissolved metals in a constructed wetland. H. trivolvis is a freshwater pulmonate snail widespread in ponds across North America. It feeds mostly on periphyton and is more or less sedentary. Snails have been used as biomonitors because several species are metal tolerant. However, compared to snails, periphytic microorganisms may track more closely dissolved metal concentrations as they take up metals principally from the water column.This study was conducted at the Monahan Pond in Kanata, Ontario (Canada). This wetland was built in 1995 to treat run-off from an agricultural and residential watershed. Water chemistry samples, snails and periphyton grown on artificial substrata were collected at both the inlet and the outlet of the wetland in the fall of 1999. Tissue samples were digested with concentrated nitric acid and metal analyses were done by ICP-MS (Inductively Coupled Plasma Mass Spectrometry). During the experiment several chemical parameters differed between the inlet and the outlet. Alkalinity was significantly higher at the inflow and all major cation concentrations were higher at the inflow. The temperature was on average 3 ºC higher at the outlet. Mass balance calculations showed that the wetland was a sink for most dissolved metals. Snails and periphyton tissue metal concentrations were higher at the inflow than at the outlet for Cd and Ni. However, no significant differences were observed between inflow and outlet tissue concentrations for Cr and Al, whereas Mn was actually significantly higher at the outlet. As a result, the metal content of the organisms did not consistently reflect the dissolved metal concentrations in water. For all metals except Cd and Zn, periphyton concentrations were on average higher than snail metal concentrations. Periphyton analyses can provide a more conservative measure of metal contamination and, when artificial substrates are used, correspond to defined and known periods of exposure.This study demonstrates that constructed wetlands may lead to increased metal content of downstream organisms even if these wetlands appear to be overall sinks for dissolved metals based on mass balance calculations. It also shows the need to consider not only metal concentrations, but also biological data when assessing the performance of pollution control facilities.

Keywords: Efficacité de traitement, gastropode pulmoné, helisoma trivolvis, marais artificiels, métaux, périphyton, Constructed wetlands, treatment efficiency, metals, periphyton, pulmonate snail, helisoma trivolvis

Contamination of surface and ground waters by persistent organic pollutants constitutes a serious environmental problem. A number of physical and biological methods have been proposed to remove these pollutants from industrial wastewater. However, many organic contaminants are not destroyed by these techniques. Various chemical treatment methods for polluted waters have been proposed. These methods are based on catalytic, electrochemical and photochemical reactions, known as advanced oxidation processes (AOPs). However, despite these treatments, there is presently no universal technique available. Because of their widespread agricultural use, chlorophenoxyacid herbicides contaminate waterways and ground waters in France and many other European countries.In the present study, we have investigated the photochemical degradation of several chlorophenoxyacids in aqueous solution at room temperature, by ultraviolet (UV) irradiation at 254 nm. We compared the efficiency of three different systems: UV alone; assisted photochemistry (UV/H2O2); and photo-Fenton reaction (UV/H2O2/FeIII). The latter photochemical system was found to represent a promising alternative approach, relative to existing methods of polluted water chemical treatment. The method photochemically destroyed the initial herbicides into CO2 and H2O. Also, it constitutes an AOP based on the in situ photochemical formation of OH· radicals. The evolution of the chemical composition of the herbicide samples studied was monitored by high performance liquid chromatography (HPLC). The mineralization of the initial herbicides was evaluated by the measurement of the chemical oxygen demand (COD) and the determination of chloride ions. The photodegradation kinetics, the nature and evolution of the photoproducts as well as the process yield were studied for the three photochemical systems for five different chlorophenoxyacid herbicides, including 2-(2-methyl-4-chlorophenoxy)propionic acid (MCPP), 4-chloro-2-methylphenoxyacetic acid (MCPA), 2,4-dichlorophenoxyacetic acid (2,4-D), 2-(2,4-dichlorophenoxy)propionic acid (2,4-DP) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T).Photodegradation by UV alone was relatively slow and partial, taking place in 1 h for MCPA, 1.5 h for MCPP and 3 h for 2,4-D. This process did not completely destroy the photoproducts. The mineralization yields for the organic matter were 64 %, for MCPA, 69 % for MCPP, 42 % for 2,4-DP and 35 % for 2,4-D, following an irradiation time of 2 h. The technique based on the photolysis of hydrogen peroxide (UV/H2O2) produced a more rapid photodecomposition, occurring within about 30 min for MCPA and MCPP and more than 60 min for 2,4-D and 2,4,5-T. The corresponding mineralization yields for the organic matter were 79 % for MCPP and 2,4-DP and 56 % for 2,4-D. The absolute rate constants for the reaction with hydroxyl radicals were found to be1.5×109, 1.6×109, 3.2×109 and 3.6×109 M-1 s-1 respectively for 2,4,5-T, 2,4-DP, MCPP and MCPA using this technique.The photo-Fenton system significantly improved the kinetic performance and mineralization yield. The photodegradation times were 7 min for MCPA, 10 min for MCPP, 40 min for 2,4-D and 60 min for 2,4,5-T, whereas the mineralization yields reach respective values of 96 % for MCPP, 95 % for MCPA, 80 % for 2,4-D, 94 % for 2,4-DP and 89 % for 2,4,5-T.

Keywords: Herbicides chlorophénoxyalcanoïques, procédé photo-Fenton, radicaux hydroxyles, minéralisation, demande chimique en oxygène, Chlorophenoxyacid herbicides, Photo-Fenton process, Hydroxyl radicals, Herbicide, Mineralization, Chemical oxygen demand

SummaryWater percolation through different soil horizons is one of the main mechanisms contributing to the improvement of the microbial quality of ground water. These soil horizons separate the soil surface from the groundwater table. Wastewater often contains chemicals and microbial pollutants, generally at high concentrations. On the other hand, ground water constitutes a major natural resource in most regions of the world. The present study was carried to examine the transfer of bacterial pollutants to the ground water, with the objective of evaluating the influence of the rate at which wastewater percolates through a soil column overlying the groundwater table.The soil column was 25 cm in diameter and one meter high. It was composed of two horizons of different heights with pH values that varied from 4.43 to 4.56. Wastewater percolation tests were carried out with volumes of 50 mL, 100 mL and 250 mL, which were introduced every 30 minutes for each experiment. Chemical analysis was performed for pH, NH4+ and electrical conductivity. Bacteriological analysis was also carried out for thermo-tolerant coliforms and faecal streptococci quantification. These analyses were first carried out on each wastewater sample before introduction into the soil column, and then again after their percolation through the soil column.Results showed that the lapse of time needed to observe the first percolated water drop was longer for low water loads than for the higher water loading rates. On the other hand, the time necessary to collect an adequate volume of percolated water for analysis was shorter for low water loads than for the high water loads. The average volume of percolated water per hour was thus high at low water loads, and relatively low at high water loading rates.A comparison of the microbial characteristics of the introduced wastewater and those of the percolated water showed that the bacterial load in the percolated water was lower. This reduction was due to bacterial retention by the soil column. At an applied load of 50 mL, this reduction was of the order of 7 log units for thermo-tolerant coliforms, and 6 log units for faecal streptococci. When water load of 250 mL was applied, the reduction was of the order of 6 log units for thermo-tolerant coliforms, and 7 log units for faecal streptococci. The reduction was in order of 7 log units for both bacterial groups at an applied wastewater loading of 100 mL. It thus appears that, at high applied wastewater loadings, the soil column retained faecal streptococci better than thermo-tolerant coliforms. The soil column behaviour was reversed when low wastewater loads were applied. It was also noted that for electrical conductivity, a reduction varying from 6,240 to 6,550 µS/cm was obtained in the water leaving the soil column. The concentration of ammonia decreased from 44‑50 mg/L at the entrance to the column to around 1 mg/L at the exit of the column. Average pH values of water percolated through the two soil horizons varied from 5.70 to 7.32, whereas pH values of water introduced into the soil column varied from 7.43 to 8.02. It thus appears that the pH of these two soil horizons strongly influenced the pH of the percolating water that would enter the underlying ground water. The chemical and bacteriological characteristics of percolating water exhibited temporal variations, showing that the retention of pollutants by the soil column was a dynamic process.

Keywords: coliformes thermotolérants, streptocoques fécaux, charge d'eau, colonne du sol, eau d'infiltration, nappe phréatique, thermo-tolerant coliforms, faecal streptococci, water percolation, soil column, water loading, ground water

A stochastic rainfall generator and a model for calculating the erosivity index of the Universal Soil Loss Equation (USLE) are coupled. The first one operates on a 30 min time step and it is calibrated on a 15 year historical pluviographic database for central Tunisia. The second model works like an automatic calculator, where the rain erosivity index can be averaged or summed. These two models are applied to simulate the annual siltation of hill reservoirs in arid and semi-arid areas of Tunisia. The catchment is considered as a "black-box" where mostly climatic aggressivity is varying (some extreme rainfall events cause most of the erosion) and the other erosion parameters are considered to remain constant over the lifetime of the reservoir. We know that the WISCHMEIER rain erosion index has no upper limit. When all the other factors are maintained constant, erosion is proportional to it. This climatic index is calculated for each rain event, but we can also calculate the annual average or sum it over many years. Soil losses (or solid transport) during a period are proportional to the value of this index summed over the same period.We demonstrate on three representative catchments lying from north to south (from 500 mm to 250 mm annual average rainfall) that the annual rain erosion index distribution can be considered comparable to the solid transport distribution (Galton distributions with equal statistical parameters).For the OUED EL HISSIANE catchment (15.9 km2), the annual extreme value of erosion is proportional to the annual extreme value of the rain erosion index. Only spring and autumn storms need be considered to calculate the annual sediment loss.On gauged small catchments like those of hill reservoirs, the rainfall generator can provide an erosivity rainfall record. Considering that the other erosion parameters are constant, this model allows one to calculate the confidence intervals of a reservoir's predicted durations. We equate the annual erosivity index distribution to the annual solid supplies distribution, and we generate and sum over several consecutive years many series of "solid supplies" to simulate the progressive silting up of the reservoirs (represented by the chosen period : sum over T=5 years, 10 years, 15 years ...). In the context of setting up hill reservoirs, this study concerns the potential duration and possible services of hydraulic structures (including the risk of rapid silting up of the reservoirs). This generator can be computed over many years and avoids the limitation due to the short observed time series.The methodological benefit of such an approach is therefore to avoid the difficulty of limited observed samples. It enlarges the data analysis of the series dispersal and residuals. This approach, based on observations and a statistical method, supports experimental analysis. It gives a clear idea of the rate of siltation, according to climatic hazards. A sensitivity analysis, where we modify the rainfall generator parameters (number of episodes and quantity of rain, peak and duration of storm...), is used to validate the methodology. A regional analysis shows a very low fluctuation considering the whole arid and semi-arid area of Tunisia. These two results led us to set up a regional abacus. This abacus reports the forecasts of the fluctuations of the time length service for hilly and small dams, including the probable average of their service duration. It allow a predetermination of the small dams' life time together with a confidence interval, and it can be used for small dam construction, planning and management. It improves the first feasibility study and can be included in economic calculations.

Keywords: Tunisie, climat aride et semi-aride, génération stochastique, érosion, index de Wischmeïer, réservoirs collinaires, durées de service, Tunisia, arid and semi-arid climate, stochastic generation, erosion, Wischmeïer index, hill reservoirs, service duration

The distinction between high and low policing is increasingly relevant in the wake of the terrorist attacks of 11 September 2001. This paper reviews the content of the high policing paradigm and addresses recent criticism. Its first part provides an update of the defining features of high policing : absorbent policing, power conflation favouring the executive, the primacy of protecting the state and massive use of infiltration through of covert informants. It is, thereafter, argued that the high and low police distinction is considered to run deeper than anticipated by the various bodies reporting on the policing and intelligence failure to prevent 9/11. In part three, the place of private security agencies in high policing is assessed. Private high policing must be taken into account, but it only shares in some of the defining features of high policing and is lacking in others. Finally, the contrast between high and low policing is examined in relation to symbolic significance.

Keywords: Haute police, police politique, basse police, police criminelle, commissions d'enquête, High policing, low policing, political police, criminal police, inquiry commission, Alta policía, baja policía, policía política, policía judicial, Comisiones de investigación