Metales en la columna de agua

Estuarine, Coastal and Shelf Science 64 (2005) 200e210 www.elsevier.com/locate/ECSS

Metal and organic carbon distribution in water column of a shallow enclosed Bay at the Aegean Sea Archipelago: Kalloni Bay, island of Lesvos, Greece
A.M. Gavriil, M.O. Angelidis*
Department of Environmental Studies, University of the Aegean, University Hill, 81100 Mytilene, Greece Received 15 June 2004;accepted 3 February 2005 Available online 2 April 2005

Abstract Metals and organic carbon concentrations in dissolved and particulate phases were determined seasonally (wet and dry periods) in four different sites of the semi-enclosed shallow marine system of Kalloni Bay in the island of Lesvos, Greece. The Bay is a typical system of many Mediterranean islands, which combine intermittent streamdischarges, lengthy dry periods and relatively light anthropogenic activities on the coastal zone and the study aimed at the investigation of heavy metal partitioning mechanisms under such conditions. Seasonal and spatial variations in metal concentrations showed that fluvial transport is the major pathway for Cu, Fe, Ni and particulate Al and Li to the Bay. Wet deposition during winter probablydetermines the distributions of Pb and Zn. Manganese distribution appears to be regulated by diagenetic processes in the sediment, leading to Mn release in the overlying water column. Lithium is transported in the very fine fraction of suspended particulate matter (SPM) and is uniformly distributed in the area. Dissolved phase is the major metal carrier for Cd, Cu, Ni, Pb and organic carbon, while Fe andMn are mainly transported in the particulate phase. Important spatial variations in metal partitioning were observed only for Ni because of the presence of nickeliferous ultrabasic minerals at the Northeastern part of the Bay. The concentrations of the human related metals (Cd, Cu and Zn) were low indicating very small anthropogenic influence in the area. The concentrations of organic carbon indissolved (DOC) and particulate (POC) phases were regulated by primary production as well as fluvial transport and were similar to enclosed eutrophic systems or estuaries. Ó 2005 Elsevier Ltd. All rights reserved.
Keywords: metals; coastal seawater; Kalloni Bay; Aegean Sea

1. Introduction Coastal areas are complex and dynamic environments that receive large amounts of material from land. Among thevarious contaminants, trace metals are of particular concern due to their environmental persistence, biogeochemical recycling and ecological risks. Metals are introduced into the marine environment through river runoff, atmospheric deposition, hydrothermal venting, diagenetic remobilization and anthro* Corresponding author. E-mail address: magel@aegean.gr (M.O. Angelidis). 0272-7714/$ - see frontmatter Ó 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.ecss.2005.02.015

pogenic activities (Libes, 1992). Industrial and agricultural activities, as well as urban effluents, are the major anthropogenic sources, which supply important loads of toxic metals to the sea. The major biogeochemical processes, which regulate the distribution and behavior of trace metals in seawater, are mixing ofwater bodies, particleewater interaction (through biological uptake and adsorptionedesorption) and diagenetic processes in sediments (Bruland, 1983; Chester, 1990a). In coastal waters, trace metal concentrations tend not to correlate well with nutrients, since external inputs (terrestrial, anthropogenic, sedimentary) and local hydrography appear to play a more important role

A.M. Gavriil,M.O. Angelidis / Estuarine, Coastal and Shelf Science 64 (2005) 200e210

201

than biogenic processes. Due to several biogeochemical and sedimentological processes that occur there, the coastal zone may act as a source or sink of trace metals (Martin et al., 1989). Cadmium, Cu, Ni, Pb and Zn commonly have significant anthropogenic sources and are of great importance from an environmental quality...