Phytoremediation study of mining soils: case of the Mibladen and Zaida mine (High Moulouya, Morocco)

The Upper Moulouya region, including the Mibladen (M) and Zaïda (Z) mines, is one of the highest lead (Pb) deposit areas in Morocco. These mines, abandoned without any measure of rehabilitation, constitute the main source of soil pollution by Metallic Trace Elements (MTEs) accumulation in the region. In this study, two greenhouse phytoremediation experiments (for the Mibladen and Zaida sites) were set up using Italian ryegrass (Lolium multiflorum) specie to assess its capacity and ability to remediate soils contaminated by zinc (Zn), cadmium (Cd), copper (Cu), and Pb. For both experiments, various factors including (i) three substrates (waste treatment [Wt]; clay uncovering [Cun]; and unpolluted control soil [Ucs]) and (ii) three treatments (no treatment, treatment with organic matter, and treatment with chemical fertilizers) were studied. The results before planting indicated that Wt substrates had poorer physicochemical properties than those of Cun, thus they are the most exposed to the degradation phenomena. This is confirmed by pollution index (PI) results that revealed the trend of PI (Z Wt)> PI (M wt)> PI (M Cun)> PI (Z Cun)> PI (Z Ucs)> PI (M Ucs). The results of experiments indicated that ryegrass crops can grow on substrates contaminated with MTEs. Depending on the applied fertilizers, available metals, and the type of soil, the phytoremediation results showed that L. multiflorum can tolerate, hyperaccumulate, and translocate MTEs from polluted substrates. Our findings suggest that this plant can be a solution for remediating alkaline soils polluted by Cd, Pb, Zn, and Cu in Mediterranean conditions

Etude petrologique et geochimique des lamprophyres et roches associees de la region de Tamazert (Haut-Atlas de Midelt, Maroc)

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Perspectives de phytostabilisation par Jatropha curcas L. des résidus miniers de la mine de Zaida (Haute Moulouya, Maroc)

Growth performance of Jatropha curcas were investigated on various substrates of abandoned lead mine of Zaida (High Moulouya, Morocco). Jatropha curcas shows proper installation despite elevated levels of trace metals and metalloids precisely Pb, Cu, Zn and As in experimental substrates. The accumulation of trace metals and metalloids (TMM) in the different compartments of Jatropha curcas depends on the type of substrate (clay uncovering, tailings, control soil). The low rate of translocation of TMM in J. curcas gives great power of phytostabilization.Les performances de croissance de Jatropha curcas L. ont été étudiées sur divers substrats de la mine de plomb abandonnée de Zaida (Haute Moulouya, Maroc). Jatropha curcas montre une bonne installation malgré les teneurs élevées en Pb, Cu, Zn et As dans les substrats expérimentaux. L’accumulation des éléments traces métalliques (ETM) dans les différents compartiments de Jatropha curcas dépend du type du substrat sur lequel elle est plantée (argile de découvrement, résidus miniers, sol témoin). Le faible taux de translocation des ETM confère à Jatropha curcas un grand pouvoir de phytostabilisation.El Himer Sarah, Bouabdli Abdelhak, Baghdad Bouamar, Saidi Naima. Perspectives de phytostabilisation par Jatropha curcas L. des résidus miniers de la mine de Zaida (Haute Moulouya, Maroc). In: Ecologia mediterranea, tome 39 n°2, 2013. pp. 19-30

Les rejets miniers de traitement : caractérisation, capacité polluante et impacts environnementaux, mine Zeïda, mine Mibladen, Haute Moulouya (Maroc)

The aim of this study is to characterize the wastes of treatment abandoned at the mine sites Zeida and Mibladen (Upper Moulouya, eastern of Morocco).highlight the polluting capacity of these wastes and determine their environmental impacts taking into account climate semi-arid and geological context carbonate and silicate in the region. The results showed that the mining wastes at Zeida (RZ) and at Mibladen (RM) consist of fine particle size, have low geotechnical stability, highly mobile and exhibit high levels of toxic trace metals (MTE) (Pb: 5547ppm for RZ//10520ppm for RM). These wastes with alkaline pH are affected by intense water erosion and in particular wind erosion and they create multiple environmental impacts. lndeed, in addition to the negative impact on the landscape that they generate, MTE contained in these wastes are transported, spread and contaminate surface water resources and soil around: (water: Pb: 13-430g/1//Sediments Pb:33-2415ppm //Soils: Pb:71-566 ppm). However, we note that the risk of contamination related to chemical weathering from the studied wastes is reduced sequel on the one hand to the Jack of moisture in semi-arid climate favoring chemical reactions within the waste and second/y due to the abundance of carbonates and 1 or silicates in wastes and into the geological terrain of the region. Phenomena of acid mine drainage (AMD), in particular acidification of surface water and leachate, most remarkable phenomenon of AMD were detected anywhere in mining districts. This is the contaminated neutral drainage (CND) for mining wastes of Zeïda and Mibladen at upper Moulouya. Mechanical wind erosion is the main vector of the dispersion of suspended particles of contaminants from wastes studied.L'objectif de cette étude est de caractériser les rejets miniers de traitement abandonnés aux centres miniers Zeïda et Mibladen (Haute Moulouya, oriental du Maroc), de mettre en exergue la capacité polluante de ces rejets et déterminer leurs impacts environnementaux tenant compte du climat semi-aride et du contexte géologique dans la région. Les résultats ont révélé que les verses à rejets miniers à Zeïda (RZ) et à Mibladen (RM) sont constituées de particules de taille fine, de stabilité géotechnique faible, très mobiles et présentent des teneurs élevées en éléments traces métalliques toxiques (ETM) (Pb : 5547ppm pour RZ//10520ppm pour RM).Ces rejets à pH alcalin (8,4) subissent l'effet d'une intense érosion hydrique et en particulier éolienne et créent de multiples impacts environnementaux. En effet, en plus de l'impact paysager négatif qu'ils génèrent, les ETM contenus dans ces rejets sont transportés, disséminés et contaminent les ressources en eaux de surface et les sols aux alentours : (Eaux : Pb : 13-430µg/l//Sédiments : Pb : 33-2415ppm//Sols : Pb : 71-566 ppm). Toutefois, on note que le risque de contamination lié à l'altération chimique à partir des rejets miniers étudiés est réduit suite d'une part au manque d'humidité en climat semi aride favorisant les réactions chimiques au sein des rejets et d'autre part suite à l'abondance des carbonates et/ou des silicates dans les rejets et dans les terrains géologiques de la région. Les phénomènes du drainage minier acide (DMA), en particulier l'acidification des eaux de surface et des lixiviats, phénomène le plus remarquable du DMA n'ont été décelés nulle part au niveau des districts miniers. Il s'agit du drainage neutre contaminé (DNC) pour les rejets des mines Zeïda et Mibladen de la Haute Moulouya. L'érosion mécanique éolienne est le vecteur principal de la dispersion, à partir des rejets miniers étudiés, de particules en suspension contaminants

Heavy Metals in Tailings,Soils and Vegetation of an Abandoned Lead Mine Land in Morocco

The High Moulouya is a region where mining industry has been developed at the beginning of the 20th century. Residues generated from past mining activities have been dumped over the years as tailing ponds. The goal of this research was to determine the concentrations of three metal trace elements (MTE) in the tailings, in two plant species (Stipa tenacissima and Artemisia herba-alba) and soils surrounding these deposits. Lead, copper, and zinc have been specifically considered. Chemical analyses have been achieved using ICP-AES. Results showed significant concentration of Pb in mining residues and vegetation that colonize the surrounding area. Concentrations of the three heavy metals in soil and plant samples were minimal at 1 km from the piles of tailings. The maximum accumulation of metals within the 50-200 m zone suggests that the surrounding vegetation forms a wind erosion obstacle resulting in metal dust deposition.La Haute Moulouya est une région où l’exploitation minière a été développée depuis le début du XXe siècle. De ce fait, les résidus miniers générés par l’activité minière ont été disposés en haldes. Le but de cette recherche est de déterminer la quantité de trois éléments traces métalliques (ETM) dans les haldes, dans la végétation steppique et les sols avoisinant ces dépôts. Le plomb (Pb), le cuivre (Cu) et le zinc (Zn) ont été spécifiquement considérés. Les analyses chimiques ont été faites par ICP-AES. Les résultats d’analyse ont montré la présence de Pb en concentrations élevées dans les résidus miniers et dans la végétation qui colonise les sols avoisinants. Les concentrations en Cu, Pb et Zn dans les échantillons de sols et de plantes sont minimales à 1 km des haldes. L’accumulation maximale des métaux dans la zone 50-200 m suggère que la végétation environnante forme un obstacle à l’érosion éolienne qui provoque le dépôt de la poussière métallique.Baghdad Bouamar, Naimi Mustapha, Bouabdli Abdelhak, Sonnet Philippe, Lutts Stanley. Heavy Metals in Tailings,Soils and Vegetation of an Abandoned Lead Mine Land in Morocco. In: Ecologia mediterranea, tome 32,2006. pp. 85-91

Data Conditioning Modes for the Study of Groundwater Resource Quality Using a Large Physico-Chemical and Bacteriological Database, Occitanie Region, France

International audienceWhen studying large multiparametric databases with very heterogeneous parameters (microbiological, chemical, and physicochemical), covering a wide and heterogeneous area, the probability of observing extreme values (Z-score > 2.5) is high. The information carried by these few samples monopolizes a large part of the information conveyed by the entire database. The study of the spatial structure of the data and the identification of the mechanisms responsible for the water quality are then strongly degraded. Data transformation can be proposed to overcome these problems. This study deals with a database of 8110 groundwater analyses (Occitanie region, France), on which the bacteriological load was measured in Escherichia coli and Enterococci, in addition to electrical conductivity, major ions, Mn, Fe, As and pH. Three modes of data conditioning were tested and compared to the treatment with raw data. The results show that log transformation is the best option, revealing a relationship between E. coli content and all the other parameters. By reducing the impact of extreme values without eliminating them, it allowed a concentration of information on the first factorial axes of the PCA, and consequently a better definition of the associated processes. The spatial structure of the principal components and their cartographic representation is improved. The conditioning of the data with the square root function led to an intermediate improvement between the logarithmic transformation and the absence of conditioning. The application of these results should allow a targeted, more efficient, and therefore, less expensive monitoring of water quality by Regional Health Agencies

Soil erodibility mapping using three approaches in the Tangiers province –Northern Morocco

Soil erodibility is a key factor in assessing soil loss rates. In fact, soil loss is the most occurring land degradation form in Morocco, affecting rural and urban vulnerable areas. This work deals with large scale mapping of soil erodibility using three mapping approaches: (i) the CORINE approach developed for Europe by the JRC; (ii) the UNEP/FAO approach developed within the frame of the United Nations Environmental Program for the Mediterranean area; (iii) the Universal Soil Loss Equation (USLE) K factor. Our study zone is the province of Tangiers, North-West of Morocco. For each approach, we mapped and analyzed different erodibility factors in terms of parent material, topography and soil attributes. The thematic maps were then integrated using a Geographic Information System to elaborate a soil erodibility map for each of the three approaches. Finally, the validity of each approach was checked in the field, focusing on highly eroded areas, by confronting the estimated soil erodibility and the erosion state as observed in the field. We used three statistical indicators for validation: overall accuracy, weighted Kappa factor and omission/commission errors. We found that the UNEP/FAO approach, based principally on lithofacies and topography as mapping inputs, is the most adapted for the case of our study zone, followed by the CORINE approach. The USLE K factor underestimated the soil erodibility, especially for highly eroded areas

Data Conditioning Modes for the Study of Groundwater Resource Quality Using a Large Physico-Chemical and Bacteriological Database, Occitanie Region, France

When studying large multiparametric databases with very heterogeneous parameters (microbiological, chemical, and physicochemical), covering a wide and heterogeneous area, the probability of observing extreme values (Z-score > 2.5) is high. The information carried by these few samples monopolizes a large part of the information conveyed by the entire database. The study of the spatial structure of the data and the identification of the mechanisms responsible for the water quality are then strongly degraded. Data transformation can be proposed to overcome these problems. This study deals with a database of 8110 groundwater analyses (Occitanie region, France), on which the bacteriological load was measured in Escherichia coli and Enterococci, in addition to electrical conductivity, major ions, Mn, Fe, As and pH. Three modes of data conditioning were tested and compared to the treatment with raw data. The results show that log transformation is the best option, revealing a relationship between E. coli content and all the other parameters. By reducing the impact of extreme values without eliminating them, it allowed a concentration of information on the first factorial axes of the PCA, and consequently a better definition of the associated processes. The spatial structure of the principal components and their cartographic representation is improved. The conditioning of the data with the square root function led to an intermediate improvement between the logarithmic transformation and the absence of conditioning. The application of these results should allow a targeted, more efficient, and therefore, less expensive monitoring of water quality by Regional Health Agencies

Assessment of water quality in abandoned lead mine environment in the high Moulouya in Morocco.

Trabajo presentado en el 12ème Conférence Inter Régionale Enviro Water celebrado en Marrakech (Marruecos) del 28 al 30 de noviembre de 2009.[FRE]La Haute Moulouya est un secteur où l'exploitation miniére a été très développée au 20érne siècle. Les résidus miniers abondants qu'elle a engendrés ont été disposés en haldes qui n'ont fait l'objet d'aucune réhabilitation sur le plan environnemental. La qualité des eaux souterraines et de surface en ce qui concerne les éléments traces métalliques a été étudiée au voisinage du centre minier abandonné de Zaida. Soixante sept échantillons d'eau ont étés prélevés au sein du territoire de la commune de Zaida le long de l'oued Moulouya qui draine le centre minier, dans des lacs de carriéres à ciel ouvert et dans des puits. Le but de cette étude est de connaître les teneurs en éléments traces métalliques (ETM) des eaux de la commune et leurs relations avec les rejets miniers. Quatre métaux lourds (Cu, Pb, Zn et Cd) ont été déterminés dans les eaux échantillonnées ainsi que les ions habituels (CI-, Ca", Na', K', Mn". Mg", Fe", SOC et NO3), le pH et la conductivité électrique. Les analyses ont été faites par ICP-AES. Les résultats d'analyse montrent que les eaux souterraines sont caractérisées par une salinité globale variable d'un puits à l'autre, une forte charge minérale et de faibles teneurs en métaux lourds pour la majorité des puits. Le Pb, le Zn et le Cu suspectés n'atteignent des concentrations élevées que dans quelques puits. D'autre part, l'analyse des rejets miniers et des eaux de surface a montré une contamination des eaux et des teneurs élevées en ETM dans les haldes. On a également noté des teneurs relativement élevées des eaux superficielles en métaux (Pb, Zn, Cu) mais pas en Cd, qui presente des concentrations relativement faibles.[ENG]The High Moulouya is a region where intensive mining activities developed during the 20th century. Abundant mining waste generated by these activities has been dumped in piles which have never been subjected to rehabilitation. The quality of ground and surface waters have been studied in the vicinity of abandoned mining center of Zaida township. The goal of this study was to determine the content of metallic trace elements (MTE) in waters of the township and to study their relationships with mining disposal. Water samples have been collected along the Moulouya River, from quarry lakes, and in existing wells. Four heavy metals Pb, Cu, Zn and Cd) in addition to usual ions (CI', Ca++, Nat, Kt, Mntt, Mg", Fe", SO4 et NO3), pH and electric conductivity have been determined in these water samples. Chemical determinations have been made using ICP-AES. Results showed that ground water is characterized by a significant global salinity which varies among wells, a high mineral load and low concentrations of heavy metals in most wells. Greater concentrations of Pb, Zn and Cu were only observed in wells that were close to the piles of barren. Analysis of mining disposal and surface water revealed a substantial contamination of water because MTE contents are higher in the barrens. Significant Pb, Zn and Cu contents were found in surface water, but not for Cd, which presented relatively low concentrations.Ce travail est réalisé dans le cadre du programme thématique d'appui á la recherche scientifique (PROTARS II) ainsi que dans le cadre d'une bourse mixte de la coopération technique belge (CTB) et du projet CNRPRST Maroc- CSIC Espagn