Search

Dissolved organic carbon (DOC) is an essential component of the biogeochemical marine system, effecting biological and chemical reactions that take place in the sea. DOC represents a dynamic component of the global carbon cycle. This paper reports 25 years of measurements of DOC content and distribution at seven stations along the transect Po River delta – Rovinj in the northern Adriatic (NA). The results show strong temporal and spatial variability: (1) The highest average DOC concentrations were observed in 1998 and 2002 (143 μmol/L and 137 μmol/L, respectively); (2) The minimum average DOC was recorded in 2006 (88 μmol/L) and (3) The short-term DOC accumulation (up to 203, average 102 μmol/L) for the years 2009 to 2012, was observed during the summer and autumn months followed by unusually low DOC concentrations during the winter and spring. The DOC results from the more recent monitoring at the same stations indicate primarily oligotrophic characteristics of the NA seawater (88 μmol/L). The results of DOC variability and distribution in the NA appears to be strongly influenced by complex circulation patterns. This paper provides a “link” between the Ionian circulation and the NA ecosystem as a part of the recently identified Adriatic-Ionian Bimodal Oscillating System (BiOS). A good agreement between the BiOS oscillation and other variables related to the DOC concentration, like the NA A and B winter types, the Po River discharge, salinity, chlorophyll a , occurrence of hypoxic-anoxic conditions, eutrophication and oligotrophication, suggests that DOC might be a good tool and indicator of global change. [ABSTRACT FROM AUTHOR]

In this paper we determined the levels of 63 environmental contaminants, including organic (PCBs, organochlorine pesticides, and PAHs) and inorganic (As, Cd, Cu, Pb, Hg and Zn) compounds in the blood of loggerhead turtles ( Caretta caretta ) from two comparable populations that inhabit distinct geographic areas: the Adriatic Sea (Mediterranean basin) and the Canary Islands (Eastern Atlantic Ocean). All animals were sampled at the end of a period of rehabilitation in centers of wildlife recovery, before being released back into the wild, so they can be considered to be in good health condition. The dual purpose of this paper is to provide reliable data on the current levels of contamination of this species in these geographic areas, and secondly to compare the results of both populations, as it has been reported that marine biota inhabiting the Mediterranean basin is exposed to much higher pollution levels than that which inhabit in other areas of the planet. According to our results it is found that current levels of contamination by organic compounds are considerably higher in Adriatic turtles than in the Atlantic ones (∑ PCBs, 28.45 vs. 1.12 ng/ml; ∑ OCPs, 1.63 vs. 0.19 ng/ml; ∑ PAHs, 13.39 vs. 4.91 ng/ml; p < 0.001 in all cases). This is the first time that levels of PAHs are reported in the Adriatic loggerheads. With respect to inorganic contaminants, although the differences were not as great, the Adriatic turtles appear to have higher levels of some of the most toxic elements such as mercury (5.74 vs. 7.59 μg/ml, p < 0.01). The results of this study confirm that the concentrations are larger in turtles from the Mediterranean, probably related to the high degree of anthropogenic pressure in this basin, and thus they are more likely to suffer adverse effects related to contaminants. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are priority contaminants that bioaccumulate through the food webs and affect the biology of a variety of resident and migratory species, including sea turtles. Few studies have evaluated toxicological biomarkers of exposure to PAHs and PCBs in these animals. The present paper reports the results of an initial field study to quantify the association between plasma concentrations of PAHs/PCBs and whole blood cell expression of gene biomarkers in juvenile loggerhead sea turtles ( Caretta caretta ) rescued along the Italian coasts of the northern and central areas of the Adriatic Sea. While detectable levels of PAHs were found in all plasma samples examined, only three PCB congeners (PCB52, PCB95, and PCB149) were noted, with detection percentages ranging between 48% and 57%. A significant correlation was found between 3 of the 6 gene biomarkers assessed (HSP60, CYP1A and ERα) and plasma levels of some PAH congeners. In contrast, no significant association between PCB burden and gene expression was observed. The global DNA methylation levels were significantly and positively correlated with the concentrations of most of the PAHs and only one of the PCB congeners (PCB52). The relation between PAH concentration and gene expression in whole blood cells suggests that these genes may respond to environmental contaminant exposure and are promising candidates for the development of biomarkers for monitoring sea turtle exposure to persistent organic pollutants (POPs). [ABSTRACT FROM AUTHOR]

This research presents a set of multi-objective spatial tools for sea planning and environmental management in the Adriatic Sea Basin. The tools address four objectives: 1) assessment of cumulative impacts from anthropogenic sea uses on environmental components of marine areas; 2) analysis of sea use conflicts; 3) 3-D hydrodynamic modelling of nutrient dispersion (nitrogen and phosphorus) from riverine sources in the Adriatic Sea Basin and 4) marine ecosystem services capacity assessment from seabed habitats based on an ES matrix approach. Geospatial modelling results were illustrated, analysed and compared on country level and for three biogeographic subdivisions, Northern-Central-Southern Adriatic Sea. The paper discusses model results for their spatial implications, relevance for sea planning, limitations and concludes with an outlook towards the need for more integrated, multi-functional tools development for sea planning. [ABSTRACT FROM AUTHOR]