© 2014 Lammini, A., A. Dehbi, H. Omari and A. Abdallaoui. This open access article is distributed under a Creative Commons Attribution (CC-BY) 3.0 license. American Journal of Geosciences Original Research Paper Study of Heavy Metals in the Surface Sediments of the Main Wadis in the Region of Meknes-Morocco Lammini, A., A. Dehbi, H. Omari and A. Abdallaoui Department of Chemistry, Analytical Chemistry and Environment Team, Faculty of Sciences, Moulay Ismail University, PO Box 11201, Zitoune, Meknes, Morocco Article history Received: 12-12-2015 Revised: 01-08-2015 Accepted: 02-02-215 Corresponding Author: Abdallaoui, A. Department of Chemistry, Analytical Chemistry and Environment Team, Faculty of Sciences, Moulay Ismail University, PO Box 11201, Zitoune, Meknes, Morocco Email: a.abdallaoui@gmail.com Abstract: Because of their growing demographic and industrial expansion, the urban areas of the city of Meknes are likely to disturb the ecological balance of watercourse. In the present work, we had evaluate the degree of sediment’s contamination by heavy metals (Al, Cd, Cu, Fe, Mn, Pb and Zn) in the main wadis of the Meknes region (Boufekrane, Wislane and Toulal) which are tributaries of the oued R’doom. These heavy metals were assayed by ICP, after the sediment mineralization by aqua regia. Reference concentrations were determined by the method of coring. In parallel to this and for the characterization of the studied sediments, we also determined the physico-chemical parameters: Carbonates, organic matter, pH and granulometry. The analysis of the whole data collected by a multivariate statistical method (factorial correspondence analysis) allowed us to distinguish five groups of heavy metals. Keywords: AFC, Watercourse, Heavy Metals, Pollution, Sediment Introduction The aquatic environment pollution has become one of the most serious nuisances, notably, that affects urban and industrial areas. The anthropic activities remain the main cause of the degradation of the quality of water in the surface: Wastewater discharges, agricultural activities notably the excessive use of fertilizers and pesticides. However, the degree of pollution of the aquatic environment by heavy metals cannot always be evaluated only on the basis of their concentration in water. Indeed, on the one hand, the concentrations of heavy metals in the water are close to the detection levels limits where the uncertainty range is large enough. On the other hand, the heavy metals are subtracted from water by multiple processes and the concentrations consequently do not reflect the real significance of pollution owed to human activities, which accelerates the process of degradation of the quality of the wadis (Saadallah, 1991). The analysis of metals in sediments appears to be a lane that allows circumventing these difficulties. Elsewhere, the process of exchange of heavy metals at the water-sediment interface in particular, in relationship with adsorption and desorption equilibria, depend of the physicochemical parameters such as organic matter, carbonates, pH and the granulometry. For example an increase in pH promotes the adsorption of selected heavy metals on the reducible fraction of sediments (iron and manganese oxides), (Vanthuyne et al., 2003; Basta and Tabatabal, 1992a; 1992b; Kribi, 2005; Zhu and Alva, 1993; Tessier et al., 1990). We therefore judged it important to determine the physicochemical parameters and evaluate metal concentrations of seven heavy metals; aluminum, cadmium, copper, iron, manganese, lead and zinc; of sediment deposited in the level of three main wadis of the Meknes region: Wislane, Boufekrane and Toulal. Materials and Methods Study Sites The sites of our work are the Wadis of Wislane, Boufekrane and Toulal, which play an important socio- economic role for the Region of Meknes; one of the most agricultural regions in Morocco. Boufekrane Wadi is a permanent watercourse of the Sais plain. It flows through the lake basin of Meknes plateau, whose substratum consists of sandy limestone of Pliocène and its coverage (agricultural land) of Tertiary and Quaternary Age. It rises to the west of El Hajeb, in the Middle-Atas, 750 m above sea level (Saadallah, 1991). It holds the name of Aïn Maarouf near the source, then that of Boufekrane 10 km from it, until after its confluence in the first place