On the Occurrence and Established Populations of the Alien Polychaete Polydora cornuta Bosc, 1802 (Polychaeta: Spionidae) in the Sea of Marmara and the Bosphorus Strait (Turkey)

The present paper reports the first occurrence of Polydora cornuta in the Bosphorus Strait and its finding in a new locality in the Sea of Marmara, providing a link with its Aegean and Black Sea populations. The probable vector for the introduction of P. cornuta into the Sea of Marmara is shipping through the Dardanelles Strait. Both soft and hard-bottom populations were examined and the importance and prevalence of this species within the native macrozoobenthic communities were elucidated. Its abundance ranged between 40 and 3390 ind.m-2 (mean:1320 ±1199.45 SD) and its percent contribution to the total faunal populations ranged between 3.31 and 75.56 (mean:27.79 ±25.00 SD) in the Sea of Marmara softbottom community. During the sampling period, P. cornuta contributed little to the total faunal abundance of the hard-bottom communities in the Bosphorus Strait. Its mean abundance in the hard substrate ranged between 8.33 and 1000 ind.m-2 (mean:117.36 ±279.73 SD) and its percent contribution to the total faunal populations ranged between 0.02 and 21.86 (mean:2.07 ±6.25 SD). The role of this invasive species in the soft-bottom macrobenthic community at an organically enriched site examined in the Sea of Marmara is highlighted, and a comparison with Aegean Sea populations of the species is also included

Application of the bentix index in assessing ecological quality of hard substrata: a case study from the Bosphorus Strait, Turkey

In this paper, a biotic index (Bentix) has been used for the assessment of ecological quality status of shallow water hard substrate benthic ecosystems affected by coastal sewage discharges in the Bosphorus Strait. A significant difference was observed between the control and the discharge stations with regard to Bentix values (Mann-Whitney U Test, p=0.002) and ecological quality status of the discharge stations was worse than that of controls. The index values revealed that sewage discharges caused serious disturbance in macrozoobenthic communities in the area investigated. Although so far it has been used for soft bottom communities, Bentix (with some species scoring modifications) also appeared to work successfully in hard substrates, at least for the present study

Genetic vs community diversity patterns of macrobenthic species: preliminary results from the lagoonal ecosystem

1 - The use of molecular data derived from multispecies assemblages in order to test ecological theory has only recently been introduced in the scientific literature.2 - As a first step, we compared patterns of abiotic environment, polychaeta distribution and their genetic diversity in five lagoon ecosystems in Greece. Our results confirm the hypothesis that higher genetic diversity is expected in the populations of the species occurring in the transitional waters rather than of those occurring in the marine environment.3 - Patterns derived from the polychaete community level and from the mitochondrial DNA (16S rRNA) obtained from Nephtys hombergii and Hediste diversicolor showed convergence, indicating the potential use of molecular matrices as surrogates in community analysis.4 - Finally, the high correlation between the genetic diversity pattern of H. diversicolor and the phosphorus concentration in the sediments may imply the broadening of the hierarchic-response-tostress hypothesis towards lower than species level

Assessment of the environmental status in Hellenic coastal waters (Eastern Mediterranean): from the Water Framework Directive to the Marine Strategy Water Framework Directive.

A  methodology is presented to assess the environmental status sensu the Marine Strategy Water Framework Directive (MSFD) based on data obtained from the monitoring of water quality in the Hellenic coastal waters within the Water Framework Directive (WFD).   An adapted decision tree used for integrating the results of the WFD in the Basque country was applied. Modifications lie to the evaluation of the physicochemical status based on a eutrophication index developed for Eastern Mediterranean waters. Results on hydromorphological, physicochemical and biological elements are presented. The chemical status was evaluated based on measurements of heavy metals in water. The evaluation of the biological quality was based on the use of metrics developed for phytoplankton biomass, benthic macroinvertebrates and macroalgae updated to accommodate MSFD needs. Results on the integrative status of the water bodies were validated by correlating classification results with a pressure index and environmental indicators in water column and sediment. Following this decision tree the majority of stations expected to be at risk of achieving the good status were found in moderate status. Benthos was found to be the element with the closest agreement with the integrated final status having an increased weighting in the decision tree. The quality of benthos and in some  limited cases  the eutrophication index determined largely the final status. The highest disagreement with the integrative classification was produced by macroalgae. All indicators used correlated with water and sediment parameters but benthos correlated better with sediment factors while phytoplankton and eutrophication index with water column parameters

ELNAIS: A collaborative network on Aquatic Alien Species in Hellas (Greece)

ELNAIS is a dynamic online information platform aiming to collect and report spatial information on Aquatic Alien Species in Greek waters. It covers freshwater, marine and estuarine waters, including not only established aliens but also casual records and cryptogenic species. The ELNAIS system includes: News, List of Greek experts, Literature of findings in Greece, List of species with information on their first introduction date and source as well as photos and distribution maps. Data providers are the scientific community (publications, grey literature, and databases) as well as citizen scientists. ELNAIS provides a useful tool towards national obligations and commitments under both the European and global frameworks in respect to Non Indigenous Species (CBD, WFD, MSFD).JRC.H.1-Water Resource

Indicator-based assessment of marine biological diversity-lessons from 10 case studies across the European seas

The Marine Strategy Framework Directive requires the environmental status of European marine waters to be assessed using biodiversity as 1 out of 11 descriptors, but the complexity of marine biodiversity and its large span across latitudinal and salinity gradients have been a challenge to the scientific community aiming to produce approaches for integrating information from a broad range of indicators. The Nested Environmental status Assessment Tool (NEAT), developed for the integrated assessment of the status of marine waters, was applied to 10 marine ecosystems to test its applicability and compare biodiversity assessments across the four European regional seas. We evaluate the assessment results as well as the assessment designs of the 10 cases, and how the assessment design, particularly the choices made regarding the area and indicator selection, affected the results. The results show that only 2 out of the 10 case study areas show more than 50% probability of being in good status in respect of biodiversity. No strong pattern among the ecosystem components across the case study areas could be detected, but marine mammals, birds, and benthic vegetation indicators tended to indicate poor status while zooplankton indicators indicated good status when included into the assessment. The analysis shows that the assessment design, including the selection of indicators, their target values, geographical resolution and habitats to be assessed, has potentially a high impact on the result, and the assessment structure needs to be understood in order to make an informed assessment. Moreover, recommendations are provided for the best practice of using NEAT for marine status assessments

Performance comparison of biotic indices measuring the ecological status base on soft-bottom macroinvertebrates: a study along the shallow Gomishan lagoon (Southeast Caspian Sea)

Abstract This paper aims to test the suitability of some biotic indices for their application in Southeast Caspian Sea. For this purpose, the ecological quality of the Gomishan lagoon was assessed using three biotic indices (AMBI, BENTIX, BOPA) during summer and autumn 2010. The results from the application of the biotic indices do not highlight a clear distinction between the stations. The results show that two of the indices (AMBI and BENTIX) are very close in terms of diagnosis (good and high) and seem to generally perform better than BOPA. In addition, Principal Component Analysis (PCA) based on abiotic parameters showed clear spatial and temporal differences in environmental variables. However, at this shallow sites with low human pressure and high water residence times, such benthic community composition can be associated with physical stress due to salinity increase and to changes in environmental characteristics, triggered by conventional seasonal variations. Natural variability of transitional waters is a crucial factor for a correct evaluation of the ecological condition of macroinvertebrate communities across the lagoonal system

European Red List of Habitats Part 1. Marine habitats

The European Red List of Habitats provides an overview of the risk of collapse (degree of endangerment) of marine, terrestrial and freshwater habitats in the European Union (EU28) and adjacent regions (EU28+), based on a consistent set of categories and criteria, and detailed data and expert knowledge from involved countries1. A total of 257 benthic marine habitat types were assessed. In total, 19% (EU28) and 18% (EU28+) of the evaluated habitats were assessed as threatened in categories Critically Endangered, Endangered and Vulnerable. An additional 12% were Near Threatened in the EU28 and 11% in the EU28+. These figures are approximately doubled if Data Deficient habitats are excluded. The percentage of threatened habitat types differs across the regional seas. The highest proportion of threatened habitats in the EU28 was found in the Mediterranean Sea (32%), followed by the North-East Atlantic (23%), the Black Sea (13%) and then the Baltic Sea (8%). There was a similar pattern in the EU28+. The most frequently cited pressures and threats were similar across the four regional seas: pollution (eutrophication), biological resource use other than agriculture or forestry (mainly fishing but also aquaculture), natural system modifications (e.g. dredging and sea defence works), urbanisation and climate change. Even for habitats where the assessment outcome was Data Deficient, the Red List assessment process has resulted in the compilation of a substantial body of useful information to support the conservation of marine habitats

A MSFD complementary approach for the assessment of pressures, knowledge and data gaps in Southern European Seas : the PERSEUS experience

PERSEUS project aims to identify the most relevant pressures exerted on the ecosystems of the Southern European Seas (SES), highlighting knowledge and data gaps that endanger the achievement of SES Good Environmental Status (GES) as mandated by the Marine Strategy Framework Directive (MSFD). A complementary approach has been adopted, by a meta-analysis of existing literature on pressure/impact/knowledge gaps summarized in tables related to the MSFD descriptors, discriminating open waters from coastal areas. A comparative assessment of the Initial Assessments (IAs) for five SES countries has been also independently performed. The comparison between meta-analysis results and IAs shows similarities for coastal areas only. Major knowledge gaps have been detected for the biodiversity, marine food web, marine litter and underwater noise descriptors. The meta-analysis also allowed the identification of additional research themes targeting research topics that are requested to the achievement of GES. 2015 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license.peer-reviewe