TY - JOUR
T1 - Seasonal variation and sources of dissolved trace metals in Maó Harbour, Minorca Island
AU - Martínez-Soto, Marly C.
AU - Tovar-Sánchez, Antonio
AU - Sánchez-Quiles, David
AU - Rodellas, Valentí
AU - Garcia-Orellana, Jordi
AU - Basterretxea, Gotzon
N1 - Publisher Copyright:
© 2016 Elsevier B.V.
PY - 2016/9/15
Y1 - 2016/9/15
N2 - The environmental conditions of semi-enclosed coastal water-bodies are directly related to the catchment, human activities, and oceanographic setting in which they are located. As a result of low tidal forcing, and generally weak currents, waters in Mediterranean harbours are poorly renewed, leading to quality deterioration. Here, we characterise the seasonal variation of trace metals (i.e. Co, Cd, Cu, Fe, Mo, Ni, Pb, and Zn) in surface waters, and trace metal content in sediments from Maó Harbour, a semi-enclosed coastal ecosystem in the NW Mediterranean Sea. Our results show that most of the dissolved trace metals in the waters of Maó Harbour exhibit a marked inner-outer concentration gradient, suggesting a permanent input into the inner part of the harbour. In general, metal concentrations in the waters of Maó Harbour are higher than those in offshore waters. Concentration of Cu (21 ± 8 nM), Fe (9.2 ± 3.2 nM) and Pb (1.3 ± 0.4 nM) are particularly high when compared with other coastal areas of the Mediterranean Sea. The concentration of some metals such as Cu and Zn increases during summertime, when the human population and boat traffic increase during the tourism season, and when resuspension from the metal enriched sediments is higher. The evaluation of the metal sources in the harbour reveals that, compared with other putative sources such as runoff, aerosol deposition and fresh groundwater discharges, contaminated sediments are the main source of the metals found in the water column, most likely through vessel-driven resuspension events. This study contributes to the understanding of the processes that control the occurrence and distribution of trace metals in Maó Harbour, thus aiding in the effective management of the harbour, and enhancing the overall quality of the seawater ecosystem.
AB - The environmental conditions of semi-enclosed coastal water-bodies are directly related to the catchment, human activities, and oceanographic setting in which they are located. As a result of low tidal forcing, and generally weak currents, waters in Mediterranean harbours are poorly renewed, leading to quality deterioration. Here, we characterise the seasonal variation of trace metals (i.e. Co, Cd, Cu, Fe, Mo, Ni, Pb, and Zn) in surface waters, and trace metal content in sediments from Maó Harbour, a semi-enclosed coastal ecosystem in the NW Mediterranean Sea. Our results show that most of the dissolved trace metals in the waters of Maó Harbour exhibit a marked inner-outer concentration gradient, suggesting a permanent input into the inner part of the harbour. In general, metal concentrations in the waters of Maó Harbour are higher than those in offshore waters. Concentration of Cu (21 ± 8 nM), Fe (9.2 ± 3.2 nM) and Pb (1.3 ± 0.4 nM) are particularly high when compared with other coastal areas of the Mediterranean Sea. The concentration of some metals such as Cu and Zn increases during summertime, when the human population and boat traffic increase during the tourism season, and when resuspension from the metal enriched sediments is higher. The evaluation of the metal sources in the harbour reveals that, compared with other putative sources such as runoff, aerosol deposition and fresh groundwater discharges, contaminated sediments are the main source of the metals found in the water column, most likely through vessel-driven resuspension events. This study contributes to the understanding of the processes that control the occurrence and distribution of trace metals in Maó Harbour, thus aiding in the effective management of the harbour, and enhancing the overall quality of the seawater ecosystem.
KW - Groundwater discharge
KW - Maó Harbour
KW - Mediterranean Sea
KW - Seawater
KW - Sediments
KW - Trace metals
UR - http://www.scopus.com/inward/record.url?scp=84965058515&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2016.03.244
DO - 10.1016/j.scitotenv.2016.03.244
M3 - Article
C2 - 27163484
SN - 0048-9697
VL - 565
SP - 191
EP - 199
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -