Iratxe Menchaca

Implementation of the European Marine Strategy Framework Directive: A methodological approach for the assessment of environmental status, from the Basque Country (Bay of Biscay)

The implementation of the Marine Strategy Framework Directive (MSFD) is directing European marine research towards the coordinated and integrated assessment of sea environmental status, following the ecosystem-based approach. The MSFD uses a set of 11 descriptors which, together, summarise the way in which the whole system functions. As such, the European Commission has proposed an extensive set of indicators, to assess environmental status. Hence, taking account of the large amount of data available for the Basque coast (southern Bay of Biscay), together with a recent proposal for assessment within the MSFD, an integrated environmental status assessment approach is developed (for the first time) in this contribution. The strengths and weaknesses of the method, combined with proposals from the MSFD, are discussed.

Source characterization and spatio-temporal evolution of the metal pollution in the sediments of the Basque estuaries (Bay of Biscay).

According to Water Framework Directive requirements, Member States must identify and analyze effects derived from human pressures in aquatic systems. As different kind of pressures can impact water bodies at different scales, analyses of spatio-temporal evolution of water bodies becomes essential in order to understand ecosystem responses. In this investigation, an analysis of spatio-temporal evolution of sedimentary metal pollution (Cd, Cr, Cu, Hg, Ni, Pb, Zn) in 12 Basque estuaries (Bay of Biscay) is presented. Data collected in extensive sampling surveys is the basis for the GIS-based statistical approach used. The implementation of pollution abatement measures is reflected in a long-term decontamination process, mostly evident in estuaries with highest historical sediment pollution levels. Spatial evolution is determined by either naturally occurring or human driven processes. Such spatial processes are more obviously being reflected in estuaries with lower historical sediment pollution levels.

Seasonal variability in gonad development in the sea urchin (Paracentrotus lividus) on the Basque coast (Southeastern Bay of Biscay).

The main limiting factor to carrying out toxicological bioassays with sea urchin larvae is the restricted period for the availability of viable gametes. Although studies have been undertaken of the reproductive cycle of the sea urchin for several areas of the Bay of Biscay, only limited information exists for the southeasternmost area (the Basque coast). Furthermore, this geographical zone presents some particular environmental conditions, e.g., relatively warm waters. In this study, the gonad state of a population of Paracentrotus lividus, settled on the rocky shores of the city of Donostia-San Sebastian have been monitored. These sea urchins are observed to behave like a typical Atlantic population, with generally high gonad indices and a single yearly main spawning period, between April and May. Further, females show a shorter spawning period than males, becoming the limiting organisms for the availability of larvae.

An empirical approach to the determination of metal regional Sediment Quality Guidelines, in marine waters, within the European Water Framework Directive

Regional Sediment Quality Guidelines (SQG) for metals from the Basque Country (northern Spain) were determined. These guidelines are proposed to be used for management purposes, within the Water Framework Directive (WFD). SQG were determined on the basis of sediment chemistry, toxicity and benthic community disturbance, from 961 estuarine and coastal samples. The guidelines were calculated using a percentile approach (effect and non-effect data), following normalisation on the fine-sediment content and with non-normalisation. The feasibility of SQG was quantified by the incidence of adverse effects, that is, the ratio of effect/no-effect data, which increased significantly with increasing SQG ranges. The study proposes the following formula to calculate SQG: SQG μg·g−1/FC. 10−2 (where FC is fine-sediment content and SQG* is the normalised SQG). The SQG* were 13.5 μg·g−1 for As, 1 μg·g−1 for Cd, 39 μg·g−1 for Cr, 55 μg·g−1 for Cu, 0.53 μ g·g−1 for Hg, 23 μg·g−1 for Ni, 78 μ g·g−1 for Pb and 249 μg·g−1 for Zn. The use of four different organisational biological levels ensures an improvement in the determination of metal regional SQG for the assessment of the chemical and physicochemical status in marine waters, within the WFD.

Determination of polychlorinated biphenyl and polycyclic aromatic hydrocarbon marine regional Sediment Quality Guidelines within the European Water Framework Directive

Marine regional Sediment Quality Guidelines (SQG) for polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) from the Basque coast (SE Bay of Biscay) were determined, on the basis of sediment chemistry, toxicity and benthic community disturbance from analysis of 756 estuarine and coastal samples. The SQG were calculated using a percentile approach (based upon effect and non-effect data), using non-normalised and normalised concentration, by total organic carbon. However, normalisation by total organic carbon did not result in any improvement in accuracy compared with non-normalised values. Hence, this study proposes non-normalised SQG values for assessment of the chemical and physicochemical status in marine waters in the Basque Country, within the Water Framework Directive: 24.6–29 μg kg−1 for total PCBs; 164–285 μg kg−1 for low molecular weight PAH; 922–1537 μg kg−1 for high molecular weight PAH; and 1607–2617 μg kg−1 for total PAH.

Application of Toxicity Identification Evaluation (TIE) procedures for the characterization and management of dredged harbor sediments

This study refers to the performance of Phase I Toxicity Identification Evaluation (TIE) procedures to identify the contaminants (i.e. organic compounds, metals and ammonia) exerting toxicity in marine sediments from the Pasaia harbor (Oiartzun estuary, northern Spain). The effectiveness of the manipulations to reduce toxicity was proved with the marine amphipod survival test (whole-sediment) and the sea urchin embryo-larval assay (elutriates). By means of TIEs it was concluded that organic compounds were the major contaminants exerting toxicity, although toxic effects by metals was also demonstrated. Additionally, the combination of Phase I treatments allowed to investigate the toxicity changes associated to the mobility of contaminants during dredging activities. Therefore, the performance of TIE procedures as another line of evidence in the decision-making process is recommended. They show a great potential to be implemented at different steps of the characterization and management of dredged harbor sediments.

Induction to maturation of the sea urchin Paracentrotus lividus (Lamarck, 1816) under laboratory conditions

Laboratory experiments were carried out over two different periods, with the aim of investigating and utilizing the induction to gonadal maturation of the sea urchin Paracentrotus lividus. The final objective was to obtain viable gametes outside the period of natural spawning in the environment; which would allow the utilization of ecotoxicological bioassays with sea urchin larvae at any time of the year. The experiment consisted of maintaining some sea urchins in tanks and providing them with a natural photoperiod, unlimited food and a constant temperature of 20 °C. During days 0, 30, 60 and 90, gonads from 15 of these sea urchins were compared with those collected simultaneously in the natural environment. The gametes obtained were used to carry out fecundations, in order to check their viability. The final results obtained were clearly influenced by the gonadal state of the sea urchins at the initial stage of the experiment. The best results were obtained within a time period of 60 days and when the initial gonad index was low.