Contaminated soils and mine tailings pose major environmental and agricultural problems worldwide. These problems may be partially solved by an emerging new technology: phytoremediation. This technique uses plants to extract soil contaminants from the ground. Thlaspi caerulescens is known to accumulate in their tissues several heavy metals from soil and aerial deposition. This study was conducted to screen plants growing on a contaminated site to determine their potential for metal accumulation. Seeds of T. caerulescens metallicolous have been collected in the vicinity of F.T. Laurent le Minier in the Pb-Zn mining district of les Malines (North of Montpellier, Southern France), and seeds of T. caerulescens nonmetallicolous were sampled on Larzac Plateau (North of Montpellier, Southern France). Soil substrates were collected from a mine site of Mibladen and Zaida (West, Morroco). Cultivated plant and surface soil samples were analyzed for zinc, lead, and cadmium concentrations by inductively coupled plasma mass spectrometry. A non-metallicolous (NM) ecotype of T. caerulescens and a metallicolous (M) ecotype are compared for Pb, Cd, and Zn accumulation in shoot and root in five metal-contaminated soils and one uncontaminated soil. The growth of individuals from uncontaminated soil was greater than that of individuals from metal-contaminated soils. The NM populations had markedly higher root/shoot ratio compared to M populations. The results indicate that both ecotypes of T.caerulescens are highly tolerant of zinc and Cd. Ecotype NM had constitutively higher Zn uptake capacity than the M ecotype. T. caerulescens species accumulate higher amount of Zn and Cd in their tissues in polluted soil and, in both of the two ecotypes, the root Pb concentrations were much greater than those of the shoot Pb contents. From both uncontaminated and metal-contaminated soils, we conclude that T. caerulescens are interesting material for phytoremediation of zinc and cadmium.

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<p>The geology and geomorphology of Moroccan Atlantic Sahara are dominated by a tabular coastal platform at altitudes of 30-35 m and a Hamada carbonate tableland with altitudes between 200 to 250 m. The coastal platform is marked by the presence of many depressions like sabkhas, lagoons while 2<sup>nd</sup>-order depressions (dayas) locally known as Grara dominate the tableands. The studied region is situated in the Saharan bioclimatic level characterized by the scarcity of precipitation.</p><p>Khnifiss, the biggest lagoon in the Moroccan Atlantic coast is the most important wetland in the Atlantic Moroccan desert. Former studies focused on sedimentary, hydrology, pollution and ecology of the lagoon, but its soil has not been mapped. Here we map the subaqueous sediment and soils of the submerged area and the soil of its surrounding areas based on remote sensing completed by field work and laboratory analysis. The soil classification system is the French Référentiel Pédologique 2008 (RP 2008). We also present a landscape map, which constitutes the first step toward a soil map, and a regional soil map at the scale of 1:150,000. The soil map shows the dominance of weakly developed soils both in fluvio-marine and aeolian dominated environments.</p><p>We also present GIS- mapped shape, morphology, size and land use of about 300 2<sup>nd</sup>-order depressions in a defined 100 sq km of a carbonate plateau. The mapping identified different types of geomorphic, hydrological and agricultural activity that lead to different types of Graras. The total area occupied by Grara covers only 3.2% of the studied area.</p>