bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical studies on the dynamics of the Northwestern Black Sea shelf
Authors: KOURAFALOU V. , TSIARAS K. , STANEVA J.
Published: May 2013

The Northwestern Black Sea shelf dynamics are studied with numerical simulations based on the Princeton Ocean Model. The study focus is on buoyancy and wind driven flows and on the transport and fate of low salinity waters that are introduced through riverine sources (the Danube, Dnestr and Dnepr Rivers), under the seasonal changes in atmospheric forcing. The study is part of the DANUBS project (NUtrient management in the DAnube basin and its impact on the Black Sea). The numerical simulations show that the coastal circulation is greatly influenced by river runoff and especially that of the Danube, which is dominant with monthly averaged values ranging from 5,000 m3 to 10,000 m3. The transport of low-salinity waters associated with the Danube runoff is greatly influenced by wind stress, topographic effects and basin-scale circulation patterns, such as changes in the position of the Rim Current.
Analysis of beak morphometry of the horned octopus Eledone cirrhosa (Cephalopoda: Octopoda) in the Thracian Sea (NE Mediterranean)
Authors: LEFKADITOU E. , BEKAS P.
Published: May 2013

Cephalopod beaks are chitinous structures situated in the buccal mass lying at the base of their arms. Because they are among the few hard structures of cephalopods with high resistance to erosion during digestive process in predator stomachs, the study of the beak morphometry is of major importance for the species taxonomy, as well as, for the size estimation of the cephalopods consumed. In this study new information is provided on the dimensions and pigmentation process of the upper and lower beak of the horned octopus Eledone cirrhosa derived from 67 female and 47 male specimens caught by trawl in the Thracian Sea (NE Mediterranean). The growth of both beaks was allometric in relation to the mantle length and body weight. According to the results of covariance analysis, no difference was found in growth pattern of beaks between sexes. Four degrees of pigmentation were identified in both upper and lower beaks, the darkening process starting in females at a smaller size.
Investigation of sea level around the island of Gavdos from ten years of TOPEX/POSEIDON satellite altimetry data
Authors: BANKS A.C. , DRAKOPOULOS P. , TSIMPLIS M.
Published: May 2013

The European Union project ‘GAVDOS’ (MERTIKAS & PAVLIS, 1999) has been designed to lead to the establishment of a calibration and sea level monitoring site for the JASON-1 and ENVISAT satellites as well as the GLObal Sea level monitoring System (GLOSS). Within the context of this project, nearly ten years of TOPEX/POSEIDON satellite altimetry data (cycle 1 to 364) from the vicinity of the Gavdos Island (Crete, Greece) have been processed and analysed. The results presented here are from the application of a method that incorporates the calculation of a corrected sea surface height from the altimetry data, along-track and cross-track data interpolation because of orbital drift, near coastal error filtering, and the use of a new geoid for the area. This method was applied in order to create ten year time series of sea level and associated parameters for the area around Gavdos island. The results reveal the pattern of sea level and local seasonal cycle around Gavdos over the last ten years.
Planktonic foraminiferal ecozones: response of the pelagic environment to palaeoclimatic changes in the eastern Mediterranean Sea
Authors: DRINIA H. , ANTONARAKOU A. , DERMITZAKIS M.
Published: May 2013

A detailed study of the planktonic environment of the eastern Mediterranean Sea has permitted the reconstruction of the climatic history of this part of the basin during the time span from 9.7 to 6.6 Ma. The eastern Mediterranean Sea is confirmed as having a strong sensitivity to the climatic changes that occurred during that timespan. One of the very few complete hemipelagic successions of the Upper Miocene in Mediterranean is found in Gavdos island (SW Crete). Quantitative and qualitative modifications of the planktonic foraminiferal communities observed in Metochia section exhibit a sequence of biological events summarized in 11 successive main time intervals. The bioevents are defined by frequency peaks and/or local (re)-occurrences or (temporary) disappearances of some of the taxa, in association with more or less important fluctuations of the more common species. The planktonic foraminifera show a strong correlation with sea surface temperature variations and with changes in the physical and chemical properties of the upper water column caused by the climatic instability. Two prominent shifts in faunal parameters divide the period recorded in Metochia section into three major time slices that are discussed in chronological order: a cooling trend from 9,7 to 7,6 Ma, a warmer period from 7,6 to 7,2 Ma and then a cooling trend which finishes at the Messinian.
Residual currents and fluxes through the mouth of Vassova coastal lagoon
Authors: SYLAIOS G. , TSIHRINTZIS V.A. , AKRATOS CH. , TSIKLIRAS A. , HARALAMBIDOU K.
Published: May 2013

An intensive sampling program of physical and chemical parameters at the mouth of Vassova lagoon (Northern Greece) during 4 separate tidal cycles is described. The study aims at understanding the tidal circulation and estimating the instantaneous and residual fluxes of water, salt and nutrients through the entrance canal of this micro-tidal lagoon. Results showed that tidal flood exceeded in duration tidal ebb, under spring and neap tidal conditions. Ebb tidal currents were recorded higher than flood currents, especially under neap tidal conditions. Unsteady flow characterized the temporal variation of longitudinal and lateral velocity, inducing a rightward deflection on flood or ebb flow. The intra-tidal variability of dissolved inorganic nitrogen showed seasonal dependence, with higher values during September, October and early March, and lower during the late March period. Residual current and flux analysis into a Eulerian and a mass transport Stokes drift mechanism illustrated that advective water and dissolved parameters (i.e., salt and nitrates, phosphates and chlorophyll-·) fluxes were an order of magnitude higher than tidal pumping effects. Water and dissolved constituents moved into the lagoon under neap tidal conditions and out of the lagoon during spring tidal conditions. Calculated flushing times ranged from 5 to 14 days, with neap tidal conditions and nearly zero freshwater discharge producing the longer flushing time. Lower water flushing effects were generated under spring tides and increased precipitation.
Evaluation Of The Radiological Situation In Algeria After The Algeciras Incident
Authors: NOUREDDINE A. , HAMMADI A. , BOUDJENOUN R. , MENACER M. , ALLALOU A. , BENKRID M. , MAACHE M.
Published: May 2013

The present study has been carried out in the framework of our environmental monitoring programme and immediately after being informed by the IAEA of possible accidental releases of 137 Cs into the air, which might have been released between May 25 th and the first of June 1998 from the Acerinox factory in Algeciras (Spain). Algericas is the region where a steel-processing factory has been set up. During the work procedure, a radioactive source of 137 Cs passed through the furnace resulting in accidental releases into the atmosphere. This radioactive contamination was detected in France, Switzerland, Italy and Germany, and some radioactivity measurements were carried out by the Commissariat A l'Energie Atomique to evaluate the gamma radiation status in areas selected in Algeria. The approach adopted in our case was to start in situ gamma-radiation measurements and to collect air and soil samples as well from a selected area in Algiers. Afterwards, and in order to have more reliable results, a sampling program was carried out in July 1998, in the frame of which some sampling stations were established in the west of Algeria, based upon Algerian meteorological data during the period of incident. A total number of 16 environmental samples from 9 stations, namely, soil, sediment, vegetation and seawater were collected, followed by in situ gamma radiation measurements in each sampling location. Soil, sediment and vegetation samples were analysed by direct gamma spectrometry, whereas, sea water samples were analysed radiochemically using microcrystalline AMP for coprecipitation and gamma counted. Taking into consideration the background levels of radioactivity in the studied areas, obtained by our previous monitoring programs, the results obtained do not show any increase of 137 Cs resulting from the incinerated Caesium source in the Acerinox steel factory in Algeciras, Spain. The conclusion drawn by this work is that the investigated area was not affected by the release of 137 Cs.
An Operational System For Monitoring Oil Spills In The Mediterranean Sea: The PROMED System
Authors: KERAMITSOGLOU I. , ASIMAKOPOULOS D.N. , CARTALIS C. , PETRAKIS M. , ARGIRIOU A. , KASSOMENOS P. , THEOPHILOPOULOS N. , NTZIOU I. , HERRERO A.M.
Published: May 2013

The primary objective of this work was the development of an operational system for early detection of oil-spills, monitoring of their evolution, and provision of support to responsible Public Authorities during cleanup operations, based on Remote Sensing and GIS technologies. In case of emergency, the principal characteristics of the oil spill are defined with the aid of a space-borne synthetic aperture radar (SAR). The transport, spreading and dispersion of the oil spill is subsequently simulated on the basis of wind forecasts of the area. The use of thematic maps of protected, fishing and urban areas, and regions of high tourism allows the better assessment of the impact of an oil spill on the areas to be affected in terms of environmental sensitivity. Finally, reports are generated notifying port authorities, the media, and local organizations to be potentially affected by the presence of the oil spill. The pilot site for testing the PROMED System in Greece is the island of Crete.
Fishery and Aquaculture Relationship in the Mediterranean: Present and Future
Authors: RELINI G.
Published: May 2013

Although the Mediterranean represents only 0.8% of the world seas, it is the site of a very long-established fishing activity, characterized mainly by multispecific catch and by artisanal or coastal activity, resulting from a mosaic of very diversified structures and gears, along more than 45,000 km of coastline. Two main biological features of this sea are the occurrence of a large richness of species (it represents 5.5% - 7% of world marine fauna and 16.6% of macrophyta), which stands in contrast with its ‘trophic poverty’ and the absence of large monospecific fishery, except for some small and large pelagic fish. Another biological characteristic of Mare Nostrumis the high invasion of exotic species, some exploited by fishery and aquaculture, some others quite dangerous. For the entire Mediterranean and Black Sea, the production (catch + aquaculture) had been steadily increasing over the period 1972-1988 from 1,140,000 t to 2,080,000 t . The period 1988-1991 has shown a drastic drop in catches (in 1991: 1,400,000 t). From 1990 to 1995 the total catch increased to 1,701,379 t then decreased and in 2000 reached 1,485,046 t . In 2000 Turkey had the first place with 496,174 t, 26.9% of the total value (1,846,026 t, including fishing and aquaculture), followed by Italy with 25%, Greece 9%, Spain 7.6% and Algeria 5.4%. As in many parts of the world, aquaculture production in the Mediterranean is rapidly expanding. In 1970 the total aquaculture production was about 18,297 t of which 74.3% produced in Italy. In 2000 a value of 358,614 t was reached, about 1/4 of the total fishery catch, while the world aquaculture production corresponds to half of the world total catch. Italy is still the main producer with 46.7% , followed by Greece with 21.5%, Turkey 9.9% and France 6.7%. A sharp drop in the production of the European eel ( Anguilla anguilla) and of the European flat oyster ( Ostrea edulis) is recorded. Positive and negative interactions between fishery and aquaculture are described for environment, food, juveniles, breeders, discards and market. Special attention is devoted to tuna farming, artificial reef and vallicultura. The response of governments and decision makers to the results and suggestions from marine scientists, proposals for urgent action in order to succeed sustainability and priority marine research areas are briefly described. Some urgent needs are outlined.
Surface sediment chemistry in the Olympic Games 2004 Sailing Center (Saronikos Gulf)
Authors: KARAGEORGIS A.P. , HATZIANESTIS I.
Published: May 2013

Construction of the Olympic Games 2004 Sailing Center is planned in the Saronikos Gulf, in the area of Agios Kosmas. A multi-disciplinary base-line study was carried out to provide background levels of inorganic and organic pollutants before the construction. Two shallow reefs (water depth 2-3 m) are the predominant features in the area’s underwater topography. The reef consists of solid rock formations and pebbles, whereas sandy sediments cover predominantly the remaining seabed. Some pockets of fine-grained sand were identified within the existing marina. Sedimentary heavy metal contents were found to be low, showing only slight heavy metal enrichment, attributed mainly to heavy mineral abundance in the area. A small enrichment for lead could be related to anthropogenic sources. Patterns of low concentrations were observed for organic carbon and organic nitrogen. Conversely, the sediment petroleum hydrocarbon content was found to be relatively high, implying anthropogenic pollution related to ship effluents and increased marine traffic.
Physical and Chemical Characteristics of Lake Edku Water, Egypt
Authors: OKBAH M.A. , EL-GOHARY S.EL.
Published: May 2013

The objective of this work is to evaluate the quality of Lake Edku water. Regional and seasonal variations of some physico-chemical parameters (nutrient salts, total nitrogen, total phosphorous and silicate, in addition to pH, total alkalinity, chlorosity, dissolved oxygen, biological oxygen demand and oxidizable organic matter) that were determined during the period from January to December 2000. Important variations have occurred in the investigated area as a result of human activity and the discharge of wastewater to the lake. The relatively low pH values reflect the decreased productivity of the Lake as a result of the polluted water discharged into the lake. Total alkalinity varied between 2.25 ± 0.35 to 8.38 ± 0.9 meq/l. In comparison with previous decades chlorosity content (586-1562 mg/l) showed the general decreasing trend. Dissolved oxygen varied (2.37 ± 0.72 - 4.47 ± 0.94 mg/l). The ratios of BOD/ OOM values indicate that the lake water has a biodegradable nature. There was a noticeable variation in ammonia levels; a lower ammonia content was recorded in summer and spring. Nitrite and nitrate concentrations in Lake Edku water showed values ranging from 3.7±1.4 to 7.8±1.9 ΜM and from 15.2±2.9 to 45.9±11.8 ΜM, respectively. The total nitrogen of the lake exhibited higher levels (53.1±12.2 – 164.2±30.7 ΜM). The ratio of NH4/TIN (0.09-0.45) seems to be highly representative of the microbial nitrification rate as well as of the varying agricultural inflows. It is interesting to note that increasing values of reactive phosphate (11.6±1.8 – 14.7±2.5 ΜM) were determined in autumn and winter respectively. The higher concentrations of reactive silicate were directly proportional to drainage water discharged into the Lake. It is clear from the mean ratio of N/P (2.4-8.8) nitrogen is the limiting factor. The lower values of N/P ratio could be related to an allochthonous condition.
High oxygen consumption rates in the deep layers of the North Aegean Sea (eastern Mediterranean)
Authors: SOUVERMEZOGLOU E. , KRASAKOPOULOU E.
Published: May 2013

Severe winter meteorological conditions promote dense water formation over the shelves of the North Aegean Sea. The newly formed dense water fills the deep basins of the North Aegean Sea, contributing to their ventilation and the downward transport of organic and inorganic material. The great bathymetric variability imposes limitations on the deep circulation and the communication between the various basins and makes the North Aegean Sea an appropriate area for the monitoring of oxygen consumption in the deep layers. Historical hydrographic data suggest that there was extensive production of dense water in the North Aegean Sea on two occasions during the last decade, the winters of 1987 and 1992-1993. Our data series from August 1986 to September 1989 and from March 1997 to February 1999, permitted us to follow, step by step, the oxygen consumption and the nutrient regeneration in the deep basins of the northern Aegean Sea during these periods of isolation. The organic matter reaching the bottom layer just after the deep water formation event is rich in labile and easily oxidizable material and its decomposition leads to a significant oxygen uptake during the first year of stagnation. The further decomposition of the remaining semi-labile and refractory material turns over on greater time scales, by consuming lesser amounts of oxygen. A more significant oxygen decrease is recorded in the eastern basin (Lemnos Basin) of the North Aegean Trough, than in the central (Athos Basin) and the western (North Sporades Basin) ones and is attributed to the irregular contribution of the Black Sea Water (BSW) to the water masses formed on the different shelves of the North Aegean Sea. Our results and the existing data on the Turkish straits showed that dissolved organic matter is the major constituent responsible for this high oxygen consumption. The slightly different particulate organic carbon fluxes to these depressions play a secondary role.
Hydrology and pollution assessment in a coastal estuarine system. The case of the Strymonikos Gulf (North Aegean Sea)
Authors: PAVLIDOU A. , HATZIANESTIS I. , SKLIVAGOU E. , PAPADOPOULOS V. , ZERVAKIS V.
Published: May 2013

Three hydrographic cruises were undertaken to study the hydrology and to estimate the ecological status of the coastal ecosystem of the Strymonikos Gulf (North Aegean Sea) impacted by the riverine waters of the Strymon River. Surface sediments were also collected in order to determine the levels of organic contaminants in the gulf. Three main water masses were identified in the Strymonikos Gulf throughout the year: a) the surface river plume water, b) the surface and subsurface Black Sea Water and c) the near bottom (>50 m) water of Levantine origin. High nutrient concentrations were recorded close to the mouth of the river, indicating a rather eutrophic environment, which was restricted near the river discharge. The salinity-nutrient correlations of the surface waters of the study area were linear, indicating that the riverine waters are the major source of nutrient in the gulf. DIN:P ratios varied seasonally from relatively higher values during winter and early spring to lower values in late spring-early summer. This led to a shift from likelihood P-limitation during winter and early spring to N-limitation in late spring – early summer. Total hydrocarbon concentrations measured in the sediments ranged from 19.2 to 95.9 μ g/g, whereas total polycyclic aromatic hydrocarbon (PAH) values varied between 107.2 and 1019 ng/g. The application of different diagnostic criteria suggests a natural terrestrial origin for aliphatic hydrocarbons and pyrolytic origin for the PAHs. DDTs displayed the highest concentrations of all the organochlorines determined, whereas polychlorinated biphenyl (PCBs) concentrations were very low. Riverine input seems to be the major source for all the compounds identified.
Typological and qualitative characteristics of Greek-interregional rivers
Authors: SKOULIKIDIS N.TH.
Published: May 2013

The catchments of the interregional rivers (I.R.) entering Greece cover an area of approximately 98000 km2, of which only 14% belongs to Greece, while their contribution to the country’s freshwater runoff reach 40% (18 km3/a). Geologically, the I.R. catchments are marked by their high percentage of acid silicates. I.R. show hydrochemical similarities, except for Evros, which is highly polluted. Compared to the other major Greek rivers, I.R. are the most polluted, with the Evros at the top, followed by the Axios. The main factors controlling their composition are climate, pollution and catchment geology. Inter-annual qualitative variations are controlled by seasonal climatic variations, which govern evaporation, groundwater contribution to river flow, dilution and flushing. A long-term salinisation of river water is attributed to climatic and anthropogenic impact. The I.R. transfer approx. 6,63 Μ t dissolved solids to the sea annually. Regarding the inputs of pollutants into the sea, they transfer over 70 % of the potassium, nitrate and dissolved organic carbon of the total load carried by major Greek rivers (78% of total Greek surface runoff), whereas for phosphate and sulphate the percentages reach 89 and 78.
Lead pollution and its sources along the Turkish coast of the Black Sea
Authors: UNSAL M.
Published: May 2013

Lead pollution and its sources have been investigated in the south-eastern and south-western Black Sea. Surficial sediments and mussels were collected in different seasons of the year from the south-eastern and south-western Black Sea and analysed for their lead contents.In the south-eastern Black Sea sediments from the easternmost and from the central stations contained the highest lead concentrations. Sediments contained 8 to 10 times the lead concentrations of sediments from the south-west. Samples taken from rivers, streams and effluents had especially high lead concentrations. The highest lead concentrations were found in sediments collected in October and December.Lead concentrations in mussels from the south-eastern coast were comparatively lower compared to those from the south-western coast. The highest average values occurred in December and in October.In the south-western Black Sea, the highest lead concentrations in sediments were obtained in those from Inebolu, followed by those from around Zonguldak. The concentrations increased from the middle to the west of the southern Black Sea coast, possibly due to the effect of the Danube River. Sediments taken in September had the highest lead concentrations, followed by samples taken in December.Very high lead concentrations (> 10 μ g g-1) were observed in mussels from those stations where the sediments also contained high concentrations. Mussels had their highest lead concentrations in January and April.
Distribution and seasonality of the marine macrophytes from Antikyra Gulf (Viotia, Greece)
Authors: MALEA P. , HARITONIDIS S.
Published: May 2013

The Gulf of Antikyra (Viotia) with a bauxitic substrate was aggravated by wastes discharged from an Aluminium factory where the Parnassos bauxite is treated Seasonal collections of macrophytes from stations selected inside the Antikyra Gulf were carried out. 85 species of macroalgae were totally collected, out of which 16 belonged to Chlorophyceae, 12 to Phaeophyceae and 57 to Rhodophyceae. There has been no obvious difference in the qualitative composition of the macroalgae as we move away from the area where the wastes are being discharged. Moreover, the stations where depths are greater exhibit different qualitative composition that those with smaller depths. The presence of phanerogams and especially that of Halophila stipulacea, the Lessepsian immigrant, encountered for the first time in the Korinthiakos Gulf, was also evident. The biomass of the three phanerogams decreased with the order: Posidonia oceanica>Cymodocea nodosa>Halophila stipulacea. The biomass of C. nodosaand P. oceanica was higher in July, while that of H. stipulacea was lower in July and higher in March and September.
Verification of seiching processes in a large and deep lake (Trichonis, Greece)
Authors: ZACHARIAS I.
Published: May 2013

A computational analysis of the periods and structure of surface seiches of Lake Trichonis in Greece and its experimental verification from three simultaneous water gauge recordings, mounted along the shores in Myrtia, Panetolio and Trichonio is given. The first five theoretical modes are calculated with a finite difference code of tidal equations, which yield the eigenperiodes, co-range and co-tidal lines that are graphically displayed and discussed in detail.Experimental verifications are from recordings taken during spring. Visual observations of the record permit identification of the five lowest order modes, including inter station phase shift. Power spectral analysis of two time series and interstation phase difference and coherence spectra allow the identification of the same five modes. Agreement between the theoretically predicted and the experimentally determined periods was excellent for most of the calculated modes.
Feeding habits of Aspitrigla cuculus (L., 1758) (red gurnard), Lepidotrigla cavillone (Lac., 1802) (large scale gurnard) and Trigloporus lastoviza (Brunn., 1768) (rock gurnard) around Cyclades and Dodecanese Islands (E. Mediterranean)
Authors: TERRATS A. , PETRAKIS G. , PAPACONSTANTINOU C.
Published: May 2013

The feeding habits of the three most abundant gurnard species, red gurnard (Aspitrigla cuculus), large scale gurnard (Lepidotrigla cavillone) and rock gurnard (Trigloporus lastoviza) in the eastern Mediterranean (Dodecanese and Cyclades, Greece) are examined. The stomach contents of the gurnard specimens collected in April and September 1996 by bottom trawling were analyzed. The % frequency of occurrence, % number and % weight of prey types in the stomach contents were evaluated. By weight, Mysidacea and Decapoda dominated in the diet of the three species in both seasons, however the Index of Relative Importance, as well as the percentage frequency of occurrence varied. Rock gurnard presented the most diverse diet whereas the diet of large scale and red gurnard were more specialized. High overlap in terms of number was found between rock and large scale gurnard in May. Rock gurnard had the most divers diet in both seasons.
Long term changes and recent state of macrozoobenthic communities along the Bulgarian Black Sea coast
Authors: TODOROVA V. , KONSULOVA T.
Published: May 2013

The analysis of macrozoobenthic samples collected from 34 stations along the Bulgarian Black Sea shelf at depths ranging from 12 to 83 m yielded 103 taxonomic units. The average abundance established in the present study was over 5000 ind/m2 with nearly 70% dominance of the polychaetes. The number of species, Shannon-Wiener diversity index (H') and Pielou's evenness (J) were the lowest in Varna and Burgas bays, indicating that they are the most ecologically threatened areas along the Bulgarian Black Sea coast. The quantitative and qualitative data were compared to published data from the pristine period 1954-1957 and from the period 1982-1985 with intensive anthropogenic pressure. The comparison revealed an increase of the share of molluscan species and a decrease of the contribution of crustacean species in the total number of species. A 7-fold increase of the total average abundance was established compared to the pristine period 1954-1957. During the recent period the polychaetes are the most dominant group in the benthic abundance, while during the pristine period 1954-1957 the most abundant were the molluscs with nearly 61% of the total abundance. These changes in the benthic communities are attributed to the process of eutrophication. While in the pelagic environment signs of recovery have been observed, we deem that up to 1997 no such signs are valid for the benthic communities.
Genetic divergence between the scad subspecies Trachurus Mediterraneus (Carangidae, pisces) from the Black Sea and the Mediterranean
Authors: DOBROVOLOV I.S.
Published: May 2013

Analysis of myogen and eleven enzymes (AAT, ADH, EST, GPI, IDHP, LDH, MDH, MEP, PGDH, PGM and SOD) were carried out by using starch gel and isoelectric focusing electrophoresis on thinlayer and ultrathin polyacrylamide ampholine and servalite gels in scad species from the Black Sea, the Sea of Marmara, the Aegean Sea, and the Mediterranean. Data from electrophoretic investigations was used to clarify the population structure of the scad migrating in the Bulgarian aquatory of the Black Sea and consisting of two main subpopulations: a) a "Black Sea" one hibernating in this sea only, and b) a "Sea of Marmara" one hibernating in that sea and contiguous Black Sea regions around the Bosporus. Non-specific muscular esterases were used, because they were appropriate for identification of both subspecies: Trachurus mediterraneus ponticus Aleev and Tr.m.mediterraneus Steindachner. Nei's genetic distance (D=0,0113) was used as an indication of their isolation dated back to the Carangate Period. An attempt was made to check the hypothesis of the origin of "large" ("giant") scad in the Black Sea as a result of the heterozygotic interbreeding between Tr.m.ponticus Aleev and Tr.m.mediterraneus Steindachner. A new allele Est-1E as well as the previously known alleles Est-1A and Est-1-B, were found in Mediterranean scad Tr.m.mediterraneus caught off Nice (France). It's proposed that the presence of the large form of large scat in this area is also a consequence of the heterozytic efect from the interbreeding between a population marked by Est-1-A and Est-1-B and a population marked by Est-1-E, probably inhabiting the waters around Gibraltar in the Atlantic Ocean.
Distribution and transfer of trace metals in the Aegean Seawater (Eastern Mediterranean Basin)
Authors: VOUTSINOU-TALIADOURI F. , ZERI C. , MORIKI A.
Published: May 2013

Recent measurements of dissolved Cd, Cu, Ni and Mn in 324 water samples of the Aegean Sea fill the gap of missing knowledge in this part of the Eastern Mediterranean and try to identify their main input sources and spreading pathways. The analyses indicate that trace metal concentrations in the North and South Aegean Sea are generally in good agreement with those reported for the Western Mediterranean Sea. In the North Aegean Sea the trace metal distribution patterns differentiate mainly according to the existing water masses. Hence, a strong influence of the Black Sea Water, enriched in trace metals, is clearly recorded for Mn. Concentrations of this metal are one order of magnitude higher in the surface layer than those of the deeper waters. This feature is followed to a lesser degree also by Cd, Cu and Ni. Trace metal concentrations in the South Aegean Sea reveal almost constant values throughout the watercolumn similar to those observed in the North Aegean Sea below the depth of 100 m. Manganese values in the South Aegean Sea are considerably lower comparing with the North Aegean ones, showing relatively enhanced surface values which decrease with depth.
Oxygen, nitrogen and sulphide fluxes in the Black Sea
Authors: KONOVALOV S.K. , IVANOV L.I. , SAMODUROV A.S.
Published: May 2013

The fluxes and production/consumption rates of oxygen, nitrate, ammonium and sulphide are estimated in the paper utilising results of the 1.5-dimensional stationary model of vertical exchange in the Black Sea (Samodurov & Ivanov, 1998). The profiles of the vertical flux and rate of production/consumption of these substances have revealed a number of intriguing features in the biogeochemical nature of the Black Sea. An approximate redox balance of the counter-fluxes of nitrate and ammonium into the sub-oxic zone has been revealed confirming that intensive denitrification may be the primary loss of nitrogen in the Black Sea. A low ratio of the nitrate stock to the flux of nitrate from the oxycline confirms the possibility of prominent changes in the distribution of nitrate on the time scale of a year. The ratio of the nitrate to oxygen vertical flux has revealed a lack of nitrate in the oxycline above the nitrate maximum. The lateral (related to the "Bosporus plume") flux of oxygen in the layer of the main pycnocline appears to be very important for the existing biogeochemical structure of the Black sea water column being the reason of sulphide consumption inside the anoxic zone and changes in the ammonium-sulphide stoichiometry of the anoxic zone, the primary reason of the existence of the sub-oxic layer and the basic reason of relative stability of the sulphide onset.
Ventilation of the Black Sea pycnocline on seasonal and interannual time scales
Authors: IVANOV L.I. , BELOKOPYTOV V.N. , OZSOY E. , SAMODUROV A.S.
Published: May 2013

The paper is a description of temporal variability of winter cooling conditions and estimation of effective cross-isopycnal mixing rates in the Black Sea. Data averaging versus salinity / sigma-t scale was used to filter effects of local dynamics. It is shown that traces of winter mixing events appear well preserved in the temperature-salinity structure, due to the peculiarities of the Black Sea where temperature often acts as a passive tracer with a smaller contribution to density as compared to salinity. Vertical distribution of the magnitudes of temperature oscillations indicates that the convection events have limited effects in modifying the structure of the middle and lower pycnocline on a seasonal time scale. However, long-term fluctuations are well recognised. The magnitudes of the seasonal and long-term temperature fluctuations are comparable only in the upper pycnocline. Three major cooling events can be distinguished from the record of the pycnocline temperature for the past 75 years. The intensive cooling occurred in the late 1920s - early 1930s, early 1950s and late 1980s - early 1990s. Partial renewal of the water of the cold intermediate layer core took place approximately once in two years. The period when convection causes erosion of the pycnocline lasts for only a week. It is shown that a lateral source of heat and salt exists for the upper pycnocline, where it is the cold intermediate water, and for the lower pycnocline, the layer below S@ 20.5, where this lateral source of salt and heat is maintained by disintegrating Bosphorus plume.
Volatile compounds of some popular Mediterranean seafood species
Authors: GIOGIOS I. , KALOGEROPOULOS N , GRIGORAKIS K.
Published: May 2013

The volatile compounds of highly commercialised fresh Mediterranean seafood species, including seven fish (sand-smelt Atherina boyeri, picarel Spicara smaris, hake Merluccius merluccius, pilchard Sardina pilchardus, bogue Boobps boops, anchovy Engraulis encrasicolus and striped-mullet Mullus barbatus), squid (Loligo vulgaris), shrimp (Parapenaeus longirostris) and mussel (Mytilus galloprovincialis), were evaluated by simultaneous steam distillation-extraction and subsequent GC-MS analysis. A total of 298 volatile compounds were detected. The mussels contained the highest total concentration of volatile compounds, while pilchard among fish species contained the highest number and concentrations of volatile compounds. Individual patterns of volatile compounds have been distinguished. The fish species when compared to the shellfish species studied, contained 6 to 30 times more 1-penten-3-ol, higher quantities of 2-ethylfuran, and 2,3-pentanedione, which was absent from the shellfish species. Pilchard is characterized by a high concentration of alcohols, shrimps by the high presence of amines and S-compounds, while mussels by high amounts of aldehydes, furans, and N-containing compounds (pyridine, pyrazines and pyrrols). The fatty acid-originating carbonyl compounds in fish seem to be related to the species’ fat content.
Establishing length-at-age references in the red mullet, Mullus barbatus L. 1758 (Pisces, Mullidae), a case study for growth assessments in the Mediterranean Geographical Sub-Areas (GSA)
Authors: BIANCHINI M.L. , RAGONESE S.
Published: May 2013

Length at age data are a fundamental tool for the assessment of exploited fish populations, their use requiring the identification of the ‘unit stock’. At the present, however, the spatial reference for stock assessment in the Mediterranean Sea is based on a grid of 30 arbitrary Geographical Sub Areas (GSA). Since older data rarely respect the GSA borders, the authors propose to reconstruct the historical data within a common frame and to assess a single reference length at age, together with the corresponding von Bertalanffy growth parameters, to be used as a broad benchmark for analyses inter and intra GSAs. This approach was tested using, as a case study, the red mullet (Mullus barbatus L. 1758), one of the most investigated fish of the whole Mediterranean basin. Published and grey literature was browsed, to get direct and/or indirect length at age estimations. To establish a common baseline and maximize the use of partial information, a vBGF (L∞, total length in mm, and Ky-1) was fitted to length at age data whenever possible. 56 Mediterranean sets were utilized; an overall reference growth line was estimated by sex, discussing its adequacy to the life traits of the species.
Assessment of the sardine (Sardina pilchardus Walbaum, 1792) fishery in the eastern Mediterranean basin (North Aegean Sea)
Authors: ANTONAKAKIS K. , GIANNOULAKI M. , MACHIAS A. , SOMARAKIS S. , SANCHEZ S. , IBAIBARRIAGA L. , URIARTE A.
Published: May 2013

The aim of this study was to describe the biometric characteristics of the European sardine (Sardina pilchardus) catches and assess the current status of sardine stock in North Aegean Sea based on population characteristics and abundance trends. The stock was dominated by age groups 1 and 2, not exceeding age group 4. The sardine stock in this area was assessed through an Integrated Catch-at-Age model which implements a separable Virtual Population Analysis on catch at age data with weighted tuning indices. Sardine landings data derived from the commercial purse seine fishery over the period 2000-2008 were combined with the age structure of the stock as resulted from fisheries independent acoustic surveys. Sensitivity analysis of the impact of natural mortality values on stock assessment results was applied. Additionally forecast of the sardine population parameters and catches under different exploitation scenarios was implemented in a medium term basis. Results indicated that the North Aegean Sea sardine stock is considered fully exploited with the fishery operating close but over the empirical exploitation level for sustainability. Finally, the status of the sardine stock in N. Aegean Sea is discussed in relation to the sardine stocks from the western and the central Mediterranean basin.
Ecological characteristics of the invasive pufferfish Lagocephalus sceleratus (Gmelin, 1789) in the eastern Mediterranean Sea – a case study from Rhodes
Authors: KALOGIROU S.
Published: May 2013

In this study, the ecological and societal impact of the invasive pufferfish Lagocephalus sceleratus on coastal habitats of an area of the eastern Mediterranean Sea (Rhodes Island) was investigated. Seasonal quantitative samplings in two common coastal habitats were used to investigate habitat use of different life-stages. Sandy areas were found to be highly important for the early life stages of L. sceleratus. In contrast, Posidonia oceanica habitats were mainly preferred by larger (> 29 cm) reproductive adults, not exceeding 64 cm. Lagocephalus sceleratus was found to feed on invertebrates and fish while size classification revealed a tendency for a diet shift with increased size. During early life stages, L. sceleratus inhabits sandy bottoms where it feeds on various invertebrates. The predominant molluscan species found in the diet of larger (> 20 cm) L. sceleratus individuals were the economically important Sepia officinalis and Octopus vulgaris. The size at which 50% of individuals reach maturity was estimated to 19 cm. With increased size, habitat shift to seagrass meadows most possibly occurs to meet both the increased demand in prey availability and requirement of appropriate spawning ground. Condition factor of L. sceleratus showed significantly higher values during summer than all other seasons and this was attributed to spawning season and increase in feeding. Societal impacts were alarming due to increased public attention concerning its lethal effects (presence of tetrodotoxin), if consumed. Its high abundance in the coastal fish communities of the studied area combined with ecological and societal impacts, clearly classify L. sceleratus a pest for fisheries and potential threat for biodiversity.
Is natural bait type a stochastic process for size and condition of fishes in the recreational fishery of Ιzmir Bay?
Authors: AYDIN I.
Published: May 2013

Determining bait type might be one of the most important factors that influence the amount and size of the fish catch in marine recreational fishery. To this end, the relationships between two types of natural bait and catch per unit effort (CPUE), yield per unit effort (YPUE), fish size and condition (K=W/TL3) were evaluated in recreational fishery İzmir Bay (Middle Eastern Aegean Sea, Turkey). The most abundant angling species in Turkish coasts; annular sea bream (Diplodus annularis), blotched picarel (Spicara flexuosa), two banded sea bream (Diplodus vulgaris) and bogue (Boops boops) were collected by anglers between September 2006 – February 2007 with using baits; onyx (Solen vagina), and sardine (Sardina pilchardus). The average CPUE and YPUE of hooks baited with onyx were significantly higher than the bait sardine. Eventhough the averages of specimens caught with bait sardine were bigger than onyx except for bogue but, total length-frequency distributions were revealed some differences only for annular sea bream and blotched picarel between two baits. High conditioned individuals of bogue were caught with bait sardine and the rest of the other species with onyx.
The Presence of the invasive Lionfish Pterois miles in the Mediterranean Sea
Authors: BARICHE M. , TORRES M. , AZZURRO E.
Published: May 2013

Here we report the occurrence of Pterois miles in the Mediterranean Sea, based on the capture of two specimens along the coast of Lebanon. Previously, only one record of the species from the Mediterranean Sea had been documented. The new records highlight the arrival of new propagules of P. miles, more than two decades later, hinting to a future potential invasion of the Mediterranean Sea.
Distribution of the Ponto-Caspian Amphipods in Turkish Fresh Waters: An Overview
Authors: OZBEK M.
Published: May 2013

To date, 13 amphipod species [Dikerogammarus haemobaphes(Eichwald, 1841); D. istanbulensis Özbek & Özkan, 2011; D. gruberi Mateus & Mateus, 1990; Echinogammarus ischnusStebbing, 1899; Pontogammarus robustoides (Sars, 1894); P. maeoticus(Sowinsky, 1894); P. aestuarius(Derzhavin, 1924); Obesogammarus turcarum Stock, 1974; Amathillina cristata Sars, 1894; Chelicorophium curvispinum Sars, 1895; C. maeoticum(Sowinsky, 1898); C. robustum Sars, 1895 and Orchestia cavimana Heller, 1865] were reported from Turkey as the representatives of Ponto-Caspian amphipod fauna. Previous records and current distributional patterns of Ponto-Caspian amphipod crustaceans in Turkish inland waters were investigated. Three new localities were revealed as one of the southernmost points in distributional area of Pontogammarus robustoides (Sars, 1894).
Recovery of the commercial sponges in the central and southeastern Aegean Sea (NE Mediterranean) after an outbreak of sponge disease
Authors: CASTRITSI-CATHARIOS J. , MILIOU H. , KAPIRIS K. , KEFALAS E.
Published: May 2013

The distribution and biometry of commercial sponges (Porifera) in coastal areas of the central and southeastern Aegean Sea was investigated to estimate the recovery progress of the populations eight years after the first appearance of sponge disease. Signs of the disease were detected only in 1.6% of the harvested sponges. Multivariate analysis on the percentage abundance of sponges showed two distinct groups among the sixteen fishing grounds studied: the eight deep (50-110 m) and the eight shallow ones (<40 m). The group from the deep depths consisted of Spongia officinalis adriatica, S. agaricina and S. zimocca. The infralittoral zone was characterized by the presence of Hippospongia communis, S. officinalis adriatica and S. officinalis mollissima. These bath sponges showed an enhanced abundance in the eastern Cretan Sea (S. Aegean Sea). In addition, their dimensions, particularly height, increased with increasing depth. It is indicated that the hydrographic conditions prevailing in the eastern Cretan Sea affected the repopulating processes of sponge banks. In each species, the biometric characteristics of the experimental specimens were similar to those of the sponges found in the market and harvested at respective depths prior to the appearance of sponge disease.
Syllinae (Syllidae: polychaeta) from the Mediterranean coast of Egypt with the description of two new species
Authors: ABD-ELNABY F.A. , MARTIN G.S.
Published: May 2013

This is the second paper dealing with the Syllidae collected on soft and hard bottom from the north-western coast of Egypt (Mediterranean Sea) and southern part of the Suez Canal. Eleven species were reported, two of them seem to be new to science, (Syllis sp.1 and Syllissp.2), but need further examination. Six species namely Opisthosyllis brunnea, Syllis columbretensis, Syllis gerlachi, Syllis ergeni, Syllis pulvinata andTrypanosyllis coeliaca were recorded as new for Egyptian waters.
One hundred years after Pinctada: an update on alien Mollusca in Tunisia
Authors: ANTIT M. , GOFAS S. , SALAS C. , AZZOUNA A.
Published: May 2013

The occurrences of non-indigenous marine molluscs in Tunisia are reviewed, based booth on a literature survey and on original material. Species are accepted as established if there are two independent reports, either geographically separate or at least one month apart in time. On these grounds, 14 species are accepted (12 alien and 2 expanding their range from elsewhere in the Mediterranean), 3 aliens need confirmation but are likely to meet the standards for acceptation on a short future, and 5 records are rebutted or questioned. Two more species may be considered as cryptogenic, the reports are reliable but it is not clear indication that they are not indigenous. Two of the alien species are reported for the first time in Tunisian waters: the nudibranch Polycerella emertoni qualifies as established, and the bivalve Anadara transversa is tentatively identified from a juvenile live-taken specimen, which awaits further confirmation.The occurrence of aliens in Tunisia is balanced between presumably Lessepsian species of tropical Indo-Pacific origin, and species from other sources including species from the Tropical Atlantic introduced through shipping. Nevertheless there is a prevalence of Lessepsian species towards the Gulf of Gabes in the south, whereas the shipping activity in Tunis harbour may be the main pathway of introduction in the north.
Dynamic downscaling of the ERA-40 data using a mesoscale meteorological model
Authors: PAPADOPOULOS A. , KORRES G. , KATSAFADOS P. , BALLAS D. , PERIVOLIOTIS L. , NITTIS K.
Published: May 2013

A sophisticated downscaling procedure that was applied to reproduce high resolution historical records of the atmospheric conditions across the Mediterranean region is presented in this paper. This was accomplished by the dynamical downscaling of the European Center for Medium-Range Forecasts ERA-40 reanalyses with the aid of the atmospheric model of the POSEIDON weather forecasting system. The full three dimensional atmospheric fields with 6 hours of temporal resolution and the surface meteorological parameters at hourly intervals were produced for a 10-year period (1995-2004). The meteorological variables are readily available at 10 km resolution and may constitute the atmospheric forcing to drive wave, ocean hydrodynamic and hydrological models, as well as the baseline data for environmental impact assessment studies. A brief overview of the procedure and a quantitative estimation of the benefit of the new dynamical downscaling dataset are presented.