abstract
Sixty sediment samples from four sites in the Bijagos archipelago were characterized for fine fraction, loss on ignition, major, minor and trace elemental composition (Al, Fe, Ca, Mg, Ti, P, Zr, Mn, Cr, Sr, Ba, B, V, Li, Zn, Ni, Pb, As, Co, U, Cu, Cs and Cd), and the elements of the La-Lu series. Element concentrations were largely explained by the Al content and the proportion of fine fraction content, with the exception of Ca and Sr. Sediments showed enhanced Ti, U, Cr, As and Cd concentrations with respect to estimated upper crust values, most likely mirroring a regional signature. Rare earth elements were in deficit relatively to the North American Shale Composite (NASC), mainly in coarser material. No pronounced Ce-anomaly was observed, while Eu-anomalies were positive in most analyzed sediments.
keywords
MARINE-SEDIMENTS; UNITED-STATES; CONTAMINATION; BIOAVAILABILITY; ESTUARINE; METALS; WATERS
subject category
Environmental Sciences & Ecology; Marine & Freshwater Biology
authors
Carvalho, L; Figueira, P; Monteiro, R; Reis, AT; Almeida, J; Catry, T; Lourenco, PM; Catry, P; Barbosa, C; Catry, I; Pereira, E; Granadeiro, JP; Vale, C
our authors
acknowledgements
This research was partially supported by the Strategic Funding UID/Multi/04423/2013 (CIIMAR), UID/AMB/50017/2013 (CESAM), CICECO (UID/CTM/50011/2013) and UID/MAR/04292/2013 (MARE) through national funds provided by FCT-Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the program PT2020. Further funds were provided by the MAVA Foundation through a project granted to IBAP (Guinea-Bissau) - 11-070 Evaluation et conservation de la biodiversite dans le Parc National Marin de Joao Vieira e Poilao. We thank IBAP sailors for important help during fieldwork. Thanks are also due to Alfredo da Silva, Aissa Regalla, and Justino Biai for granting permissions for work in the protected areas and for all facilities and logistical support. Rui Monteiro (SFRH/BD/108535/2015), P.M. Lourenco (SFRH/BPD/84237/2012) and I. Catty (SFRH/BPD/102637/2014) were supported by national funds through grants from FCT.