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Ymittos Athens, Greece

Tzoraki O.,University of Aegean | De Girolamo A.-M.,CNR Institute of Neuroscience | Gamvroudis C.,Technical University of Crete | Skoulikidis N.,HCMR
International Journal of River Basin Management | Year: 2016

A new approach, the ‘Naturalness Status' (NS), is suggested to classify the hydrologic alteration of temporary rivers from natural conditions based on the Hydrological Status Tool (HS-Tool). The HS-Tool considers two metrics: the degree and the predictability of dry flow conditions for both natural flow and its alterations, at each water body in actual and natural conditions. The Soil and Water Assessment Tool (SWAT) model is simulating the river flow of Evrotas water bodies, Greece, under natural, actual and climate-impacted conditions. The majority of Evrotas water bodies (72%) experience good (low-impacted) NS for the examined period (1990–2010), despite their intermittent flow regime. Severe flow alteration is predicted for 57% of Evrotas water bodies (high-impacted NS), while selecting the KNMI-RACMO2 future climate projections scenario (2020–2060) as input into the SWAT model. Hydrologic extreme drought phenomena or anthropogenic pressures in water regime can be quantified by the NS. The method is intended to be used in basin decision-making analysis at fulfilling the Water Framework Directive goals. © 2015 International Association for Hydro-Environment Engineering and Research.

Moncheva S.,Institute of Oceanology BAS | Pantazi M.,HCMR | Pautova L.,Russian Academy of Sciences | Boicenco L.,NIMRD Grigore Antipa | And 2 more authors.
Turkish Journal of Fisheries and Aquatic Sciences | Year: 2012

The quality of biological data has gained recognition as an essential part of international monitoring programmes, in response to the demand for strategic environmental evaluations such as the EU WFD, the MSFD and informed decisions for environmental sound management. The paper presents the results of an intercalibration exercise among four Black Sea phytoplankton laboratories (NIMRD-RO, IBSS-UKR, IO-RAS - RUS and IO-BAS - BLG) conducted under SESAME FP6 Project with the objectives: 1) to assess the degree of comparability of phytoplankton and chlorophyll a data produced by routine in-house methods; 2) to formulate recommendations for progress towards harmonization of the research methodology in the Black Sea. The statistical treatment of the results reveal that at the level of total phytoplankton abundance and biomass as well as chlorophyll a the data were in a good agreement, while for some taxonomic classes (Prymnesiophyceae and small flagellates) the differences were significant. The counted sample volume proves essential for detection of species diversity and the methods of species specific biovolume measurements - for the total biomass. As a follow up Guidelines for QC/QA of phytoplankton data and check-list with suggested shapes for biovolume calculation were produced under UP-Grade Black Sea SCENE FP7 Project that offer key options for progress. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey.

Favali P.,EMSO Coordinator | Beranzoli L.,I.N.G.V. | Materia P.,I.N.G.V. | Picard J.B.,French Research Institute for Exploitation of the Sea | And 17 more authors.
MTS/IEEE OCEANS 2015 - Genova: Discovering Sustainable Ocean Energy for a New World | Year: 2015

EMSO (European Multidisciplinary Seafloor and water-column Observatory; http://www.emso-eu.org) is a large-scale European Research Infrastructure (RI) of the ESFRI roadmap composed of fixed-point, seafloor and water-column observatories with the basic scientific objective of near- and realtime, long-term monitoring of environmental processes related to the interaction between the geosphere, biosphere, and hydrosphere. It is geographically distributed in key sites of European waters, spanning from the Arctic, through the Atlantic and Mediterranean Sea to the Black Sea. © 2015 IEEE.

Delfanti R.,ENEA | Ozsoy E.,METU - MEMS Center | Kaberi H.,HCMR | Schirone A.,ENEA | And 5 more authors.
Journal of Marine Systems | Year: 2014

The vertical profiles of 137Cs were determined in the North Aegean, Marmara and Black Seas, to assess inventories and fluxes of the radionuclide in these basins. The inventory of 137Cs in the Western Black Sea integrated from the surface down to 400m water depth is 3.4±0.1kBqm-2, which is surprisingly close to the amount determined in 1988, decay corrected to 2007 (2.9±0.1kBqm-2). On the other hand, based on the comparison of profiles roughly 20years apart, it is estimated that about 1kBqm-2 has been transferred from above the halocline to depths below the halocline, emphasizing the effective redistribution of tracers within the same period. We estimate that about 12TBqy-1 of 137Cs presently leaves the Black Sea with the upper layer flow through the Bosphorus and only 2TBqy-1 is returned with the lower layer inflow of Mediterranean water from the Marmara Sea. Accounting for river fluxes, estimated on the order of 2TBqy-1 few years after the Chernobyl accident, and possibly decreased by now, we can thus estimate a net rate of loss of about 8-10TBqy-1.Investigating the effective redistribution in the upper water column, the supply by the inflowing Mediterranean water alone does not explain the increase of 137Cs concentration and inventory at intermediate depths in the Western Black Sea. The most important mechanism transferring 137Cs and dissolved contaminants from the surface water to the sub-pycnocline layer appears to be the turbulent entrainment of a larger quantity of Black Sea water into the inflowing plume of Mediterranean water through mixing processes on the southwestern shelf and continental slope following its exit from the Bosphorus. This process produces an extra export of some10TBqy-1 of 137Cs from the surface to the sub-pycnocline depths of the Black Sea, a quantity comparable in magnitude to the total export out from the basin. It is the entrainment flux resulting from the mixing, and the further advection and penetration of this water into the Black Sea deeper layer (200-600m) that seems to maintain the inventory with little change over time. Through these two processes the Black Sea surface layer (0-50m) loses every year about 4% of its total inventory of 137Cs. © 2013 Elsevier B.V.

Kontoyiannis H.,HCMR | Lykoysis V.,HCMR
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2011

The East Mediterranean deep thermohaline cell is a series of processes that refer to the water sinking during winter at specific locations and the subsequent spreading that fills the deep near-bottom layers of the East Mediterranean with oxygen-rich water masses. These waters tend to preserve the hydrologic characteristics (temperature, salinity, and transparency) of their formation region. Hydrographic sections offshore from Cape Passero (west Ionian Sea) and near the southwest tip of Peloponnisos (east Ionian Sea), in the framework of the deep-neutrino-telescope-related KM3net program, cut through a bottom plume of Adriatic water at ∼3500 m in the southwest Ionian and a deep vein at ∼3200 m of Cretan water in the southeast Ionian. In the period 20062009, the Adriatic plume, originally characterized by a strong signal of locally higher salinity and oxygen and lower transparency in the near-bottom 500 m, tends to weaken and shrink within the near-bottom ∼200 m in 2009. This weakening trend may be associated with the relatively warm/mild winters following 2006. It may be typical inter-annual variability or a signature of global warming in which case an expected prolonged continuation can potentially affect the deep oxygen supply. © 2010 Elsevier B.V. All rights reserved.

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