Tadla Plain Research Articles

Groundwater NO3 concentration and its potential health effects in Beni Moussa perimeter (Tadla plain, Morocco)

In this research, the concentrations of nitrates were investigated in well water sampled from the irrigated perimeter of Beni Moussa (Tadla plain, Morocco), and human health risks via ingestion and dermal pathways for individuals in different age brackets were assessed using the chronic daily intake, the dermal absorbed dose and hazard index (HI).The results showed that the groundwater NO3 contents were between 4.20 to 80.46 mg L− 1, with an average of 32.11 mg L− 1, indicating anthropogenic inputs caused by the infiltration of nitrates not consumed by plants or surface industrial and domestic wastewater into the shallow aquifer. Compared to the Moroccan standard, 17.78%, 40.00%, 37.78% and 4.44% of sampled wells showed poor, fair, good or excellent quality, respectively. For non-carcinogenic risk, the oral ingestion of nitrate appeared to be the main exposure pathway for local human receptors causing the high non-carcinogenic risk, and the dermal exposure met within the accepted precautionary criterion. Infants in the study area are more likely to experience adverse effects to higher nitrate level in groundwater (3.04E-01 < HI < 1.80E+ 00), followed by female (2.39E-01 < HI < 1.41E+ 00), then male (2.22E-01 < HI < 1.31E+ 00) and finally children (2.08E-01 < HI < 1.23E+ 00). The resulting spatial variation in HI values was greatly influenced by human activities and population density.The results of this study could help to shape effective environmental management measures for enhancing the groundwater quality and ensuring safe drinking water.

Spatial repartition and contamination assessment of heavy metal in agricultural soils of Beni-Moussa, Tadla plain (Morocco)

Spatial repartition and contamination assessment of heavy metal in agricultural soils of Beni-Moussa, Tadla plain (Morocco)

A modelling approach to assess technology effect on wheat farms performance in semi-arid areas

In order to improve socio-economic conditions in rural areas, the purpose of this study is to develop models for estimating wheat yield based on the use of agricultural inputs. The emphasis is not only on increasing production, but on economically efficient production that optimises productive resources. Thereby, a cost efficiency analysis for wheat producers was conducted based on a sample of 111 farmers in the Tadla Plain in central Morocco. To achieve this objective, two models devoted to wheat yield estimation in terms of costs and quantities of agricultural inputs were developed, based on stepwise regression approach. Furthermore, data envelopment analysis (DEA) method was used to analyse the cost efficiency of farms. Overall, this work separates the excess costs related to technical efficiency and economies of scale to cost efficiency in order to understand the type of actions that farmers can take to reduce production costs and ensure their resilience.

Phosphatic series under Plio-Quaternary cover of Tadla Plain, Morocco: Gravity and seismic data

The Ouled Abdoun sedimentary basin in Morocco contains the largest phosphate reserves in the world. To the Northwest of the basin, the phosphate layers crop out or are at a shallow depth and are exploited in open pit mines. By contrast, towards the central and southwestern parts of the basin, the phosphate layers lay below the Plio-Quaternary sediments of the Tadla Plain. This study aims to characterize the distribution and structure of the phosphatic series at depth under this cover, in particular to guide the future exploration and exploitation of the phosphate deposits. The work is based on gravimetric and seismic data acquired in a previous oil exploration study, calibrated by borehole data. The analysis of the gravity data controlled by boreholes first reveals the existence of large regional faults in the basin, forming pronounced gradients in the gravity data. The faults are also seen in the seismic profiles. In the Southeast of the basin, the phosphatic series exhibit a stairway structure controlled by some of these regional faults.The drilling data and the isochron maps established from the seismic profiles show that the base of the phosphatic series is more than 500 m deep in the southeastern area of the basin. As the phosphatic layers get buried deeper, they also become thicker. The phosphate reserves thus increase towards the southeast, and our analysis identifies the areas where this reserve is larger. Our results eventually suggest that the mining methods currently adopted in the Khouribga mining district will need to be modified and adapted to the more complex situation of the phosphatic series deeply buried in the basin.

Using Statistical Analysis to Assess Urban Groundwater in Beni Mellal City (Morocco)

The study was carried out in a shallow phreatic aquifer in the piedmont zone between the Atlas Mountains and Tadla plain in Morocco. This study is carried out using physicochemical analyses with statistical analysis (CA and PCA) to show variability of groundwater hydrochemical parameters beneath Beni Mellal city in order to know spatial variability of water quality under urban activities. Total dissolved solid shows large variation from 355 mg/L to 918 mg/L with high values recorded, as electric conductivity, in the city center. High sulfate content is intercepted also in the old city center with values exceeding the threshold in the Moroccan guideline. Sulfate ions are often suspected of having an anthropogenic origin. All water samples show a dominance of Ca against Mg (Ca/Mg: 1.08–6.25) and HCO3 against SO4 (HCO3/SO4: 0.29–6.92). For most of the trace elements, the measured concentrations were far below the standard values except Al and Fe in some samples which exceed all guideline values. PCA of all dataset highlights eight factors with eigenvalues higher than 1 that explained about 80.34% of the total variance. The first two components PC1 and PC2 explained about 41.14% of the total cumulative variance and were responsible for 24.25% and 16.89% of the variance for each one, respectively. The component PC1 is mostly correlated with electric conductivity, TDS, and chloride. The component PC2 was highly correlated with Ca, Cr, and Zn. The dendrogram at a linkage distance of about 10.5 leads to dividing the diagram into three clusters of water samples, C1, C2, and C3. Cluster C1 shows a medium content of EC, HCO3, and NO3 and low content of TDS, Ca, Mg, Na, K, SO4, and Ba compared with C2 and C3. C1 samples show the lowest ion content, resulting probably from the minimal time of residence within the aquifer with low rock interactions. Cluster C2 regroups samples with high content of Ca, Mg, K, SO4, Al, and Cr, medium content of TDS and Na, and low content of EC, HCO3, NO3, and Cl. Samples in cluster C3 have more content of heavy metal (Cd, Fe, Mn, and Ni), CE, TDS, Ca, Mg, Na, HCO3, NO3, and Cl, with low content of Cr and Al and medium values of K and SO4. We recommended the monitoring and follow-up of the water quality under the city and the repair of pipes especially in the downtown area to limit unwanted infiltration. Spatial autocorrelation used with variograms and Moran'I leads to conclude that groundwater parameters varied differently according to the direction, which means that the semivariance depended on direction and distance between samples.

Health risk assessment of nitrates in the groundwater of Beni Amir irrigated perimeter, Tadla plain, Morocco

Shallow groundwater contaminated with nitrates may result in human health risks. Groundwater quality in the Beni Amir irrigation perimeter in Tadla plain, Morocco, is influenced by agriculture and farming-related activities. This study was carried out to assess the nitrate contamination of groundwater for drinking purposes by comparing it to Moroccan and WHO guidelines, and by estimating the potential human health effect of nitrates using the model recommended by the USEPA. The results showed that the nitrate content of groundwater fall between 0 and 82.08 mg L−1 (mean 24.73 mg L−1), with 38.10% of groundwater samples exceed the Moroccan and WHO limits for drinking. Groundwater nitrates mainly originated from intensive agricultural practices. The health effects of oral exposure to nitrate are higher than those of dermal exposure. For non-carcinogenic risks, 57.14% of samples showed hazard index (HI) values >1, indicating potential risks. The non-carcinogenic risk for infant and female are higher than that for females and males. The results of this study will offer a health risk reference for local residents and can help to propose suitable management ensuring safe drinking water.

Mapping of Soil Salinity Using the Landsat 8 Image and Direct Field Measurements: A Case Study of the Tadla Plain, Morocco

Soil salinization from arid to semiarid climate is a serious environmental problem. In some countries, salinization is considered a real threat to food security and food quality because it lowers crop yields and can irretrievably damage land. In the irrigated area of the plain of Tadla (Central Morocco), the intensive use of groundwater and saline surfaces lead to the degradation of soil quality. Experimental methods of monitoring soil salinity by direct real-time measurements are in high demand, but also very limited in terms of spatial coverage. The objective of this paper is to map soil salinity in the arid and semiarid zone of the Tadla plain in Morocco, based on optical remote sensing data and field measurements of sodium absorption ratio. The first results of work were devoted to the evaluation and validation of salinity models in the study area. Observations on the site, correlation, verification and validation of the model enabled us to map the salinity. All these use the soil salinity map based on non-saline soil content, light saline soil, moderate saline soil and highly saline soil. The map obtained from our model allowed us to identify the distribution of salinity in the study area. The values of the electrical conductivity in the study area range from less than 2 ds/m (non-saline soil) to more than 8 ds/m (highly saline soil) with a significant variation between the different levels of soil salinity in the study area.

Assessment of the heavy metal contamination using GIS-based approach and pollution indices in agricultural soils from Beni Amir irrigated perimeter, Tadla plain, Morocco

In agricultural soils, the contamination of heavy metals has become a major source of soil pollution in the world because of intensive agriculture practices. This paper aimed to assess the heavy metal contamination in the Beni Amir irrigated perimeter in Tadla plain, Morocco, using various geoaccumulation index and Geographical Information Systems (GIS). Forty seven subsurface agricultural soil samples were analyzed for Zn, Cr, Pb, Cu, and Cd contents. The results revealed that soils were contaminated by metals having concentrations (Zn: 294.7 mg/kg, Cr: 57.0 mg/kg, Pb: 33.3 mg/kg, Cu: 25.9 mg/kg, and Cd: 1.8 mg/kg) exceeding the WHO and FAO limits. Moreover, the highest metal contents were noticed around industrial areas and agglomerations. In our study area, the geoaccumulation indexes (Igeo), enrichment factor (EF), contamination factors (CF), and Load Pollution Index (PLI) are confirmed the anthropogenic sources of heavy metals. The spatial pattern for Zn, Cr, Cd, and Pb revealed that the contamination are related to the land use and to the influence of anthropogenic pollution and soil properties such as soil pH, organic matter, and clay mineralogy.

Multivariate statistical analysis for spatial evaluation of physicochemical properties of agricultural soils from Beni-Amir irrigated perimeter, Tadla plain, Morocco

ABSTRACTSoil surveying and mapping is an important operation in soil science, and characterization of their properties is a key step in understanding soil quality . This study was undertaken to investigate the spatial variability of selected soil properties, such as soil pH, electrical conductivity (EC1:5), carbonate content (CaCO3) and total organic matter (TOM) and soil texture using different conventional analytical methods. Spatial distribution of these soil properties was elaborated by using the kriging method. The obtained results showed that the soil is alkaline, soil pH ranges from 7.20 to 8.78. TOM varies from 0.11 to 1.05 dS/m, and its texture varied from sand to loam content. Nonetheless, EC values fall within the slight, moderate and strong degrees of salinity. According to these results, it can be concluded that the soil is saline. Interrelationships between the parameters analyzed and the different samples were investigated by multivariate analyses, principal component analysis (PCA), and hierarchical cluster analyses (HCA). HCA classified the five groups, which were compared to PCA visualizations. The Box-plots show that the values fractions (sand, silt, clay) were very variable. Pearson correlation coefficient indicates a high correlation between carbonate content and pH, organic matter and silt fraction

GIS-based multi-criteria land suitability analysis for sustainable agriculture in the northeast area of Tadla plain (Morocco)

Assessment of soil suitability for sustainable intensive agriculture is an appropriate tool to select the land suitable for agricultural production with the least economic and environmental costs. This study was conducted to evaluate the agricultural soil quality in the northeast area of Tadla plain (Morocco) using geographic information system (GIS) and analytical hierarchy process (AHP). Six soil quality indicators, i.e., pH, organic carbon, cation exchange capacity, texture, salinity and slope were considered and performed in 60 subsurface soil samples. AHP method was utilized to identify the weight of each indicator from the pairwise comparison matrix. The weighted sum overlay analysis was then used to generate the soil quality map in a GIS environment, by overlaying both indicator weights and sub-indicator weights. The studied area was classified into four soil quality categories, i.e., poor, medium, good, and excellent, the percentage of each category is 1.12, 20.98, 61.07 and 16.83%, respectively. The results indicated that 1.12% of the study area has poor suitability for sustainable intensive agriculture due to their unsuitable texture and low salinity, while about 77% of cultivated soils are adapted to agricultural production. The above results could be useful for the management of agricultural activity.

Remote sensing approach to assess salt-affected soils in the north-east part of Tadla plain, Morocco

Recently, the remote sensing technologies have been used increasingly in various domains in order to explain or detect different phenomena in a rapid manner and covering large areas. This study aims to use Landsat 8 Oli imagery product to elaborate a map of soil salinity in the north-east part of Tadla plain, by implication of spectral reflectance and electrical conductivity (EC) measured in the laboratory. Based on salinity Index (SI), the Normalized Differential Salinity Index (NDSI), and Landsat bands, we carried out a statistical study via the JMP13 software to determine the most correlated bands with EC measured. The obtained results were very satisfactory with an R2 = 71.3% and root mean square error (RMSE) of 0.084. The elaborated map showed that the salinity is high near Oum Er Rbia River and the two cities of Beni-Mellal and Ouled Yaich, which is due to saline waters of Oum Er Rbia River and Béni-Moussa-East (Dir) groundwater used for irrigation. These results signify that the combination of remote sensing and laboratory EC measurements would be a suitable method for predicting soil salinity.

Multivariate analysis and GIS-based soil suitability diagnosis for sustainable intensive agriculture in Beni-Moussa irrigated subperimeter (Tadla plain, Morocco)

The aim of this study was to diagnose the agricultural land quality in Beni-Moussa irrigated subperimeter, Tadla plain (Morocco), and to evaluate that whether they are still suitable for sustainable intensive agriculture using GIS and physicochemical analyses. Eight quality indicators, namely soil depth, soil texture, pH, EC, CEC, OC, OM and slope, and were analyzed in 27 topsoil samples (0–20 cm) collected from the study zone at September 2009–2015. GIS approach was used to provide than indicator specific maps and to generate the land suitability for intensive agriculture. The results showed that about 1.69% (1324.38 ha) of studied area are classified in the class ‘excellent suitable’, 17.14% (13449.81 ha) in ‘good suitable’, 75.70% (59393.30 ha) in ‘medium suitable’ and 5.47% (4293.11 ha) in ‘poor suitable’ for sustainable intensive agriculture. These two latter land suitability classes needed some restrictions on agricultural practices and appropriate management to be of good sustainable productivity, without soil deterioration and negative effects on environment. The findings of this study are promising and can be used as a basis for the further scientific works, but they required new investigations and experts’ opinions to evaluate and increase their accuracy.

Mapping and Characterization of Agricultural Systems from Time Series of Normalized Difference Vegetation Index (NDVI) in the Northeast Area of Tadla, Morocco

Introduction: Agriculture is the focus of sustainable development and food security in Morocco, contributing 14% to the national economy and its socio-economic impact depends on agro-climatic conditions and the availability of water resources. The objective of this work is to demonstrate that agriculture in Morocco, and especially in the Tadla region, is distributed according to the availability of underground water. Method: This work was carried out in the transition zone between the phosphate plateau and the plain of Tadla, a site of more than 124,000 ha. To achieve the objectives set, we used Landsat-8 OLI (Operational Land Imager) data sharpened to 15 m. The Support Vector Machine (SVM) classifications were applied to the 10-period Normalized Difference Vegetation Index (NDVI) series. Results: It is shown that agriculture in Morocco is highly dependent on irrigation. In the classified map, it can be observed that the southern region, a zone with a semi-arid climate, which generally relies on irrigation, is very developed in agriculture, whereas in the north most of the soil is bared with cereals that mainly depend on rainfall. Conclusion: The possible water shortage in the region puts food availability in Morocco at risk of inadequacy. Food security depends on the availability of water, a natural resource at risk of extinction. Therefore, strategies to reduce the risk of agricultural drought must be at the forefront of Moroccan policies.

Spatiotemporal monitoring of soil salinization in irrigated Tadla Plain (Morocco) using satellite spectral indices

Soil salinization is major environmental issue in irrigated agricultural production. Conventional methods for salinization monitoring are time and money consuming and limited by the high spatiotemporal variability of this phenomenon. This work aims to propose a spatiotemporal monitoring method of soil salinization in the Tadla plain in central Morocco using spectral indices derived from Thematic Mapper (TM) and Operational Land Imager (OLI) data. Six Landsat TM/OLI satellite images acquired during 13 years period (2000–2013) coupled with in-situ electrical conductivity (EC) measurements were used to develop the proposed method. After radiometric and atmospheric correction of TM/OLI images, a new soil salinity index (OLI-SI) is proposed for soil EC estimation. Validation shows that this index allowed a satisfactory EC estimation in the Tadla irrigated perimeter with coefficient of determination R2 varying from 0.55 to 0.77 and a Root Mean Square Error (RMSE) ranging between 1.02 dS/m and 2.35 dS/m. The times-series of salinity maps produced over the Tadla plain using the proposed method show that salinity is decreasing in intensity and progressively increasing in spatial extent, over the 2000–2013 period. This trend resulted in a decrease in agricultural activities in the southwestern part of the perimeter, located in the hydraulic downstream.

Soil Salinity Characterization Using Polarimetric InSAR Coherence: Case Studies in Tunisia and Morocco

The phenomenon of soil salinization in semi-arid regions is getting amplified and accentuated by both anthropogenic practices and climate change. Land salinization mapping and monitoring using conventional strategies are insufficient and difficult. Our work aims to study the potential of synthetic aperture radar (SAR) for mapping and monitoring of the spatio-temporal dynamics of soil salinity using interferometry. Our contribution in this paper consists of a statistical relationship that we establish between field salinity measurement and InSAR coherence based on an empirical analysis. For experimental validation, two sites were selected: 1) the region of Mahdia (central Tunisia) and 2) the plain of Tadla (central Morocco). Both sites underwent three ground campaigns simultaneously with three Radarsat-2 SAR image acquisitions. The results show that it is possible to estimate the temporal change in soil electrical conductivity (EC) from SAR images through the InSAR technique. It has been shown that the radar signal is more sensitive to soil salinity in HH polarization using a small incidence angle. However, for the HV polarization, a large angle of incidence is more suitable. This is, under considering the minimal influence of roughness and moisture surfaces, for a given InSAR coherence.

A GIS-Based Inventory of Ornamental Stone and Aggregate Operations in the Beni-Mellal Region (Morocco)

Straddling between two contrasting structural features, the High-Atlas in east and the Tadla plain in west, the Beni-Mellal region has a diversified and enormous potential in terms of natural resources, especially building materials and ornamental rocks. The material quarries became widespread and represent one of the significant economic activities in the region. The aim of this study was to develop a GIS-database that includes several themes (layers) in order to properly locate all exploited quarries in the Beni-Mellal region and to analyze its relationship with geology, hydrographic and road networks, and market area. The material extraction takes place by the open-pits in rivers and by the quarries in the Atlas piedmont. The majority of aggregate such as sand and gravel is produced from alluvial deposits, flood plains, and stream terraces located along the Oum Er-Rbia and Oued Derna Rivers and its tributaries. The quarries located in the Atlas piedmont produce crushed rock aggregates from limestone and brecciated dolomite rocks of Lias age. More easily accessible, they could provide long-term quarry material production (in tonnage and quality), meeting the needs of the inhabitants of the region. Also, the Beni-Mellal Atlas region offers huge reserves ornamental rocks, namely travertine and limestone onyx deposited in the dolomite and coral-reef limestone of Lias.

Mapping soil salinity in irrigated land using optical remote sensing data

Soil salinity caused by natural or human-induced processes is certainly a severe environmental problem that already affects 400 million hectares and seriously threatens an equivalent surface. Salinization causes negative effects on the ground; it affects agricultural production, infrastructure, water resources and biodiversity. In semi-arid and arid areas, 21% of irrigated lands suffer from waterlogging, salinity and/or sodicity that reduce their yields. 77 million hectares are saline soils induced by human activity, including 58% in the irrigated areas. In the irrigated perimeter of Tadla plain (central Morocco), the increased use of saline groundwater and surface water, coupled with agricultural intensification leads to the deterioration of soil quality. Experimental methods for monitoring soil salinity by direct measurements in situ are very demanding of time and resources, and also very limited in terms of spatial coverage. Several studies have described the usefulness of remote sensing for mapping salinity by its synoptic coverage and the sensitivity of the electromagnetic signal to surface soil parameters. In this study, we used an image of the TM Landsat sensor and field measurements of electrical conductivity (EC), the correlation between the image data and field measurements allowed us to develop a semi-empirical model allowing the mapping of soil salinity in the irrigated perimeter of Tadla plain. The validation of this model by the ground truth provides a correlation coefficient r² = 0.90. Map obtained from this model allows the identification of different salinization classes in the study area.

Use of multivariate statistical and geographic information system (GIS)-based approach to evaluate ground water quality in the irrigated plain of Tadla (Morocco)

Twenty five chemical, physical and bacteriological features of water samples from 25 wells were analyzed by multivariate statistical tools to provide the characterization of the ground water distribution in the basin of Tadla province (Morocco). The 25 parameters determined include: temperature, pH, conductivity, IP (permanganate index), dry residue (RS), total hardness, total iron (FeT), several bacteriological residues (faecal, total coliforms and faecal streptococcus) and several cations and anions (Ca2+, Na+, K+, Mg2+, SO42−, Mn2+, NH4+, NO3, HCO-3 , NO-2, Cl−). All sampling was performed in the period between December 2007 and February 2007(rain season). Principal Component Analysis together with the GIS approach (kriging methods) which provided a description of the area investigated with respect to the characteristics of the ground water was used. It is demonstrated that the water, quality in this region is critical. Nitrate levels are situated between 11.3 and 100 mg/L, with 73% of the observations exceeding the critical level of 50 mg/L fixed by the standards of the World Health Organization (WHO) for drinking water. However, bacteriological residues (faecal, total coliforms, and faecal streptococcus) are retrieved in nearly all water samples. Principal Component Analysis indicates that Bacteriological contamination is merely correlated with nitrite and ammonia amount rather than with nitrate amount, indicating a possible contribution of local pollution sources to ground water deterioration. The variability of the nitrate and bacteriological pollution is important and spatially correlated. A significant difference in water composition has been highlighted between water table of Beni Amir and water table of Beni Moussa and also a difference between ground water near cities (with a probable human polluting effect) and zones far from the built-up areas. Cluster analysis was also performed in order to evaluate the different wells similarity and to confirm the results obtained by Principal Component Analysis. Key words: Morocco, ground water quality, Kriging methods, principal component analysis, geographic information system (GIS), multivariate analysis.

Contact of languages and populations in Morocco

The objective of this dissertation is language and populations contact in the plain of Tadla, situated in central Morocco around the city of Beni Mellal. This language contact setting presupposes common human and linguistic facts made up of heterogeneity, mixing, variation both within the same language, the same group of people as well as within different human groups. The languages concerned in this study are mainly Amazigh and Arabic and, to some extent, French. The groups investigated are the Chleuh, the Arabized, the Arabs and the Amazighized. The contact between the languages and groups concerns the linguistic ideal parallelism and the ideal identity. This research falls within a larger scope: that of the regionalisation and decentralisation in Morocco and could be introduced as an element for territory planning of the area investigated. This work could be a preliminary initiative study of the region of Tadla from a historical, demographic, geographical, linguistic and anthropological point of view. A good knowledge of the Moroccan territory and populations requires knowledge of the distribution of the languages and the populations and their point of contact. The study of the language and populations contact will help to apprehend the mixing and consequently predict the human and linguistic evolution and changes (i.e. the emergence of a mixed language) and lead to a redefinition of regionalisation on the basis of the linguistic and cultural particularities based on the findings of fieldwork research. From this perspective, our research has the advantage of dealing with a rural micro-structure, which will be described on the basis of the characteristic of the Arabic lect of Tadla, the linguistic features of the contact between Amazigh and Arabic, the impact of the socio-cultural interpenetration between the groups present, the maps of the linguistic boundaries which set the limits of isoglosses, the regional atlases of the lects and populations of the so-called contact areas, i.e. the plain of Tadla. The originality of the research consists in the investigation of both the languages and their populations on the basis of epilinguistic speech. Former works on the region have dealt with either one or the other. The study does not limit itself to the description of the phenomena but it also aims at accounting for and explaining the convergences between the populations and languages thanks to the consideration of all the elements which could influence variation. Our aim, indeed, is not to pre-categorize the range of manifestations of language and populations contact but to apprehend its modes. The general tendency is to show that the different human groupings in Tadla do in no way differ since they have the same representation of the world. The only difference lies in the modes of expression they use i.e. either Amazigh or Arabic to express their perception of the world. The goal is thus to give a general view about the lects in use, to provide a large corpus of epilinguistic speech and to propose a model for its categorization and interpretation. We aim at revealing that what appears to be different and dissimilar on the surface is nothing but the incarnation of the facets of the same and unique, profound and inherent characteristic, i.e. the Moroccan character. Given the dimension and nature of the language and populations contact data in the area of Tadla, we had to opt for an eclectic theoretical and methodological model that would include different models and disciplines such as geography, history, dialectology, sociolinguistics, sociology of language, anthropology, psychology, discourse analysis and linguistics. Thus, on the theoretical and methodological level, we have made use of an eclectic model including different perspectives that allow for the analysis of one or many aspects of the issue. The research methods used in this study (i.e. the indirect interview, participatory observation, direct “in vivo ” testimonies…) and the multi-disciplinary approach initiates a perspective that focuses on the group and the subjectivity of the discursive speech. The description of the language and population context that characterizes the area of Tadla led us to organize the study into two main parts: a descriptive and an interpretative part. This is mainly based on a methodological principle which aims at satisfying both the descriptive and the prescriptive levels. The practices and /or usages and the general theoretical model are raised and described in the first part. The epilinguistic speech is presented, discussed and interpreted in the second part. Since the speech is conceived as a causality that can modify the practices, the speech and practices are not considered at the same level of analysis.

The Hydraulic Exchanges between the Main Water Reservoirs of the Moroccan Middle Atlas Region Measured by Solid State Nuclear Track Detectors

Uranium and thorium contents were evaluated in water samples collected from different sources of the piedmont of the Middle Atlas mountains by using two types of solid state nuclear track detectors (SSNTD). In addition, the radon (222Rn) and thoron (220Rn) α-activities per unit volume of the water samples were also determined. The influence of the water flow rate and altitude on the radon concentration of the water samples belonging to the piedmont of the Middle Atlas mountains was investigated. The hydraulic exchanges between the Middle Atlas water reservoirs and the Turonian aquifer of the neighbouring Tadla plain have been quantified. The results were compared with data given in literature.