title: Environmental impact of intensive aquaculture: investigation on the accumulation of metals and nutrients in marine sediments of Greece.
abstract: The impact of intensive aquaculture activities on marine sediments along three coastal areas in Greece was studied. The content of nine metals/metalloids (Cu, Cd, Pb, Hg, Ni, Fe, Mn, Zn, As), and three nutrients (P, N and C), that seem to accumulate in marine sediments, was determined under the fish cages (zero distance) and away (50 or 100 m) from them. Elevated concentrations for phosphorus, nitrogen, copper, zinc and cadmium were recorded in the areas where farming establishments are moored. In parallel, the intrinsic differences between the aquaculture facilities and their seasonal variations were investigated. The individual characteristics of each farm (local water currents, facilities' capacity, transferring mechanisms or the geological background) were the determinant factors. On the contrary, significant seasonal differences were not recorded. Statistical techniques, as the non-parametric Mann-Whitney U and Kruskal-Wallis tests and principal components analysis (PCA), factor analysis (FA) and discriminant analysis (DA), were used for the evaluation of the results. These chemometric tools succeeded to discriminate the sampling points according to their distance from the cages or the origin of the sample. Variables' significance, correlations and potential accumulation sources were also investigated.
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece.
authors.forename: Eleni G
authors.initials: EG
authors.lastname: Farmaki
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece. Electronic address: ntho@chem.uoa.gr.
authors.forename: Nikolaos S
authors.initials: NS
authors.lastname: Thomaidis
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece.
authors.forename: Ioannis N
authors.initials: IN
authors.lastname: Pasias
authors.affiliation: Nireus Aquaculture S.A., 1st klm. Koropiou-Varis Avenue, 19400 Koropi, Greece.
authors.forename: Cecile
authors.initials: C
authors.lastname: Baulard
authors.affiliation: Nireus Aquaculture S.A., 1st klm. Koropiou-Varis Avenue, 19400 Koropi, Greece.
authors.forename: Leonidas
authors.initials: L
authors.lastname: Papaharisis
authors.affiliation: Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece.
authors.forename: Constantinos E
authors.initials: CE
authors.lastname: Efstathiou
mesh_terms: D000818:Animals; D017756:Aquaculture; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D006115:Greece; D008670:Metals / Q000032:analysis*; D009584:Nitrogen / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D012621:Seasons; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D008670:Metals; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen
keywords: Aquaculture; DA; FA; Marine sediments; Non-parametric techniques; PCA