209 research outputs found

    ESTIMATION OF THE DENSITY OF BUCCINUM-UNDATUM (GASTROPODA) OFF DOUGLAS, ISLE-OF-MAN

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    The density of the common whelk (Buccinum undatum L.) off Douglas, Isle of Man, was determined by four methods: (1) pot sampling, (2) diving, (3) mark-recapture experiment, and (4) underwater television. Although the values obtained by these methods were comparable, the last two methods yielded overestimations of Buccinum density. The results from diving survey and from pot sampling showed a good agreement, indicating that pot sampling can be used to determine the density of the common whelk, provided a good estimate of the pot attraction area is available. The range of whelk density between February 1989 and August 1990 resulting from pot sampling was between 0.08 and 0.38 individuals m-2. The temporal fluctuations of the whelk densities are discussed in detail

    Pan-European infrastructure for ocean and marine data management (SeaDataNet II)

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    The overall objective of the SeaDataNet II project is to upgrade the present SeaDataNet infrastructure into an operationally robust and state-of-the-art Pan-European infrastructure for providing up-to-date and high quality access to ocean and marine metadata, data and data products originating from data acquisition activities by all engaged coastal states, by setting, adopting and promoting common data management standards and by realising technical and semantic interoperability with other relevant data management systems and initiatives on behalf of science, environmental management, policy making, and economy. SeaDataNet is undertaken by the National Oceanographic Data Centres (NODCs), and marine information services of major research institutes, from 31 coastal states bordering the European seas, and also includes Satellite Data Centres, expert modelling centres and the international organisations IOC, ICES and EU-JRC in its network. Its 40 data centres are highly skilled and have been actively engaged in data management for many years and have the essential capabilities and facilities for data quality control, long term stewardship, retrieval and distribution. SeaDataNet II will undertake activities to achieve data access and data products services that meet requirements of end-users and intermediate user communities, such as GMES Marine Core Services (e.g. MyOcean), establishing SeaDataNet as the core data management component of the EMODNet infrastructure and contributing on behalf of Europe to global portal initiatives, such as the IOC/IODE – Ocean Data Portal (ODP), and GEOSS. Moreover it aims to achieve INSPIRE compliance and to contribute to the INSPIRE process for developing implementing rules for oceanography.EU, Funded under :FP7-INFRASTRUCTURES-2011-

    Fall and rise of the Black Sea ecosystem

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    Güney Avrupa Denizlerinde Politika Yönelimli Deniz Çevresi Araştırmaları

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    The overall scientific objectives of PERSEUS are to identify the interacting patterns of natural and human-derived pressures on the Mediterranean and Black Seas, assess their impact on marine ecosystems and, using the objectives and principles of the Marine Strategy Framework Directive as a vehicle, to design an effective and innovative research governance framework based on sound scientific knowledge. Well-coordinated scientific research and socio-economic analysis will be applied at a wide-ranging scale, from basin to coastal. The new knowledge will advance our understanding on the selection and application of the appropriate descriptors and indicators of the MSFD. New tools will be developed in order to evaluate the current environmental status, by way of combining monitoring and modelling capabilities and existing observational systems will be upgraded and extended. Moreover, PERSEUS will develop a concept of an innovative, small research vessel, aiming to serve as a scientific survey tool, in very shallow areas, where the currently available research vessels are inadequate. In view of reaching Good Environmental Status (GES), a scenario-based framework of adaptive policies and management schemes will be developed. Scenarios of a suitable time frame and spatial scope will be used to explore interactions between projected anthropogenic and natural pressures. A feasible and realistic adaptation policy framework will be defined and ranked in relation to vulnerable marine sectors/groups/regions in order to design management schemes for marine governance. Finally, the project will promote the principles and objectives outlined in the MSFD across the SES. Leading research Institutes and SMEs from EU Member States, Associated States, Associated Candidate countries, non-EU Mediterranean and Black Sea countries, will join forces in a coordinated manner, in order to address common environmental pressures, and ultimately, take action in the challenge of achieving GES.EU, Funded under : FP7-OCEAN-201

    The Comb Jelly Mnemiopsis Leidyi in the Black Sea

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    Following its transportation in ballast waters, the western Atlantic ctenophore Mnemiopsis leidyi caused a striking damage to the ecosystem of the Black Sea in the early 1990s. The concentration of food Zooplankton and simultaneously catches of anchovy and other pelagic fishes sharply decreased during the peak levels of the ctenophore. There have been many studies on the distribution and physiology of this ctenophore in its new environment due to its substantial impact on the marine ecosystem. Later in mid 1990s its biomass was at moderate levels till the appearance of its predator, another ctenophore Beroe sp. in 1997. The predator decreased Mnemiopsis biomass to very low levels which was confirmed by both laboratory and field observations. Now Mnemiopsis is causing very similar problems in the Caspian Sea following its transport from the Black Sea.1st editio

    UP-GRADE BLACK SEA SCIENTIFIC NETWORK (UP-GRADE BS-SCENE)

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    The recently finished FP6 RI Black Sea SCENE project has established a Black Sea Scientific Network of leading environmental and socio-economic research institutes, universities and NGO’s from the countries around the Black Sea and has developed a distributed virtual data and information infrastructure that is populated and maintained by these organisations to improve the identification, access, exchange, quality indication and use of their data and information about the Black Sea. The Black Sea SCENE research infrastructure stimulates scientific cooperation, exchange of knowledge and expertise, and strengthens the regional capacity and performance of marine environmental data and information management, underpins harmonization with European marine data quality control/assessment procedures and adoption of international meta-data standards and data-management practices, providing improved data & information delivery services for the Black Sea region at a European level. The Up-Grade of Black Sea SCENE project aims: a) to extend the existing research infrastructure with 19 marine environmental institutes/organizations from the 6 Black Sea countries, b) to implement the results of the Joint Research Activities of the FP6 RI SeaDataNet project (common communication standards and adapted technologies to ensure the datacenters interoperability), c) to network the existing and new Black Sea datacenters, active in data collection, and provide integrated databases of standardized quality on-line, d) to realize and improve on-line access to in-situ and remote sensing data, meta-data and products and e) to adopt standardized methodologies for data quality checking to ensure the quality, compatibility and coherence of the data issuing from so many sources. The Up-Grade Black Sea SCENE project is undertaken by 51 partners of which 43 are located in the Black Sea countries.EU, Funded under :FP7-INFRASTRUCTURES-2008-

    Recent dramatıc changes in the Black Sea ecosystem the reason for the sharp decline in Turkish anchovy fisheries

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    As a result of eutrophication caused by increased nutrient input via major rivers during the last few decades, the Black Sea ecosystem has been subject to extreme changes in recent years. These changes first became evident in the 1980's, with abnormal phytoplankton blooms and a large increase in medusae (Aurelia aurita) biomass. Then, the introduction of a new species (a lobate ctenophore, Mnemiopsis sp.) into the Black Sea radically affected the whole ecosystem. This species competes with anchovy for the edible zooplankton as well as possibly consuming anchovy eggs and larvae in the Black Sea. The mass occurence of Mnemiopsis appears to be one of the most important reasons for the sharp decrease of anchovy and other pelagic fish stocks in the Black Sea. Although the future of the Black Sea ecosystem seems rather bleak, it is suggested that in addition to reducing anthropogenic impact, systematic studies are essential if the Black Sea fisheries are to recovery

    Determination of age and growth of Buccinum undatum L (Gastropoda) off Douglas, Isle of Man

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    Age and growth of Buccinum undatum off Douglas (Isle of Man, U.K.)were studied using four independent methods: length-frequency analyses (LFA), operculum analysis (OA), mark-recapture experiment (MRE) and laboratory rearing (LR). Within the 16-month period between February 1989 and June 1990, only the January 1990 sample showed histograms allowing possible age group determination Among the several length frequency analyses applied to this sample, the growth analysis program MIX calculated that Buccinum reaches mean lengths of 28.5, 45.8, 59.9, 71.5 and 81.0 mm at the end of its first, second, third, fourth and fifth year, respectively, with an asymptotic length (L(infinity)) of 123.8 mm and Brody growth coefficient (K) of 0.20. Whilst the results from the LFA were supported by those from the OA and the MRE, growth in the laboratory differed; however, this was expected. Both K and L values found in this study are higher than those in two previous studies undertaken for Buccinum in northeastern England and northern France
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