Metal levels in sediments and transplanted mussels in Pagassitikos Gulf (Aegean Sea, Eastern Mediterranean)

We present the development of a 3D full-lifecycle, individual-based model (IBM) for anchovy and sardine, online coupled to an existing hydrodynamic/biogeochemical low-trophic level (LTL) model for the North Aegean Sea. It was built upon an existing 1D model for the same species and area, with the addition of a horizontal movement scheme. In the model, both species evolve from the embryonic stage (egg+yolk sac larva) to the larval, juvenile, and adult stages. Somatic growth is simulated with the use of a “Wisconsin” type bioenergetics model and fish populations with an adaptation of the ‘super individuals’ (SI) approach. For the reference simulation and model calibration, in terms of fish growth and population biomass, the 2000-2010 period was selected. Interannual biomass variability of anchovy was successfully represented by the model, while the simulated biomass of sardine exhibited low variability and did not satisfactorily reproduce the observed interannual variability from acoustic surveys. The spatial distribution of both species’ biomass was in relatively good agreement with field data. Additional single-species simulations revealed that species compete for food resources. Temperature sensitivity experiments showed that both species reacted negatively to a temperature increase. Anchovy, in particular, was more affected since its spawning and larval growth periods largely overlap with the period of maximum yearly temperature and low prey concentration. Finally, simulation experiments using IPCC climatic scenarios showed that the predicted temperature increase and zooplankton concentration decrease in the future will negatively affect anchovy, resulting in sardine prevalence.

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Lessepsian migrants expanding their distributional ranges; Pseudonereis anomala (Polychaeta: Nereididae) in Izmir Bay (Aegean Sea)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315405011203h ◽

2005 ◽

Vol 85 (2) ◽

pp. 313-321 ◽

Cited By ~ 15

Author(s):

Melih Ertan Çinar ◽

Zeki Ergen

Keyword(s):

Shallow Water ◽

Eastern Mediterranean ◽

Aegean Sea ◽

Hard Substratum ◽

Izmir Bay ◽

Lessepsian Migrants

A total of ten specimens of Pseudonereis anomala (Polychaeta: Nereididae) were collected on the shallow water hard substratum (0·2 m) at four stations located in the inner part of Izmir Bay (Aegean Sea, eastern Mediterranean) in January 2004. The absence of this species among the material collected previously at the same stations might suggest that it has recently become established in the area. A re-description of the species together with its ecological, reproductive, feeding and distributional aspects are provided.

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Greek-French defence deal will widen Turkish rifts

Emerald Expert Briefings ◽

10.1108/oxan-db264706 ◽

2021 ◽

Keyword(s):

Eastern Mediterranean ◽

Aegean Sea ◽

Content Type ◽

Low Level ◽

Defence Procurement

Significance A win-win deal for both, it strengthens their long-standing excellent relations. It also enhances Greece’s military position in the Aegean Sea and France’s presence in the Eastern Mediterranean. However, following a peaceful summer in the Aegean, the pact risks raising tensions between Greece (and Cyprus) and Turkey over maritime borders and drilling rights. Impacts US-Greek defence agreement will be updated to cover a long-term arrangement, allowing for more investment in US bases in Greece. Turkish defence procurement from Russia is likely to rise, straining ties with Washington. Low-level exploratory talks between Greece and Turkey will continue as scheduled amid mutual recriminations.

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Heterozygosity fitness correlations and generation interval of the Norway lobster in the Aegean Sea, eastern Mediterranean

Journal of Biological Research-Thessaloniki ◽

10.1186/s40709-019-0103-0 ◽

2019 ◽

Vol 26 (1) ◽

Author(s):

Georgios A. Gkafas ◽

Marianthi Hatziioannou ◽

Emmanouil E. Malandrakis ◽

Costas S. Tsigenopoulos ◽

Ioannis T. Karapanagiotidis ◽

...

Keyword(s):

Eastern Mediterranean ◽

Aegean Sea ◽

Recruitment Strategy ◽

Breeding Period ◽

Nephrops Norvegicus ◽

Norway Lobster ◽

Genetic Impact ◽

Potential Population ◽

High Gene ◽

Local Residents

Abstract Background Comprehensively detailed information on population dynamics for benthic species is crucial since potential admixture of individuals could shift the genetic subdivision and age structure during a full breeding period. The apparent genetic impact of the potential recruitment strategy of Norway lobster Nephrops norvegicus is still under research. For this reason the present study was focused on genetic variation of the species over a given continuous year period in a semi-enclosed gulf of the Aegean Sea. Results Analyses revealed that the relative smaller size class in females and the apparent faster growth of males may represent a key-role differential strategy for the two sexes, whereas females tend to mature slower. Heterozygosity fitness correlations (HFCs) showed substantially significant associations suggesting that inbreeding depression for females and outbreeding depression for males are the proximate fitness mechanisms, respectively. Conclusions Nephrops norvegicus uniformal genetic composition (background of high gene flow), could be attributed to potential population recolonization, due to a hypothesized passive larval movement from deeper waters, which may suggest that some offspring of local residents and potential male non-breeders from other regions admixture randomly.

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Key Environmental Factors Controlling Planktonic Foraminiferal and Pteropod Community’s Response to Late Quaternary Hydroclimate Changes in the South Aegean Sea (Eastern Mediterranean)

Journal of Marine Science and Engineering ◽

10.3390/jmse8090709 ◽

2020 ◽

Vol 8 (9) ◽

pp. 709

Author(s):

Christina Giamali ◽

George Kontakiotis ◽

Efterpi Koskeridou ◽

Chryssanthi Ioakim ◽

Assimina Antonarakou

Keyword(s):

Environmental Factors ◽

Environmental Changes ◽

Late Quaternary ◽

Eastern Mediterranean ◽

Planktonic Foraminifera ◽

Explanatory Power ◽

Principal Component ◽

Aegean Sea ◽

Late Glacial ◽

The South

A multidisciplinary study was conducted in order to investigate the environmental factors affecting the planktonic foraminiferal and pteropod communities of the south Aegean Sea. Aspects of the Late Quaternary paleoceanographic evolution were revealed by means of quantitative analyses of planktonic foraminiferal and pteropod assemblages (including multivariate statistical approach; principal component analysis (PCA)), the oxygen (δ18O) and carbon (δ13C) isotopic composition of planktonic foraminifera and related paleoceanographic (planktonic paleoclimatic curve (PPC), productivity (E-index), stratification (S-index), seasonality) indices, extracted by the gravity core KIM-2A derived from the submarine area between Kimolos and Sifnos islands. Focusing on the last ~21 calibrated thousands of years before present (ka BP), cold and eutrophicated conditions were identified during the Late Glacial period (21.1–15.7 ka BP) and were followed by warmer and wetter conditions during the deglaciation phase. The beginning of the Holocene was marked by a climatic amelioration and increased seasonality. The more pronounced environmental changes were identified during the deposition of the sapropel sublayers S1a (9.4–7.7 ka BP) and S1b (6.9–6.4 ka BP), with extremely warm and stratified conditions. Pteropod fauna during the sapropel deposition were recorded for the first time in the south Aegean Sea, suggesting arid conditions towards the end of S1a. Besides sea surface temperature (SST), which shows the highest explanatory power for the distribution of the analyzed fauna, water column stratification, primary productivity, and seasonality also control their communities during the Late Quaternary.

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The Christiana–Santorini–Kolumbo Volcanic Field

Elements ◽

10.2138/gselements.15.3.171 ◽

2019 ◽

Vol 15 (3) ◽

pp. 171-176 ◽

Cited By ~ 2

Author(s):

Paraskevi Nomikou ◽

Christian Hübscher ◽

Steven Carey

Keyword(s):

Eastern Mediterranean ◽

Eastern Mediterranean Region ◽

Aegean Sea ◽

Volcanic Eruptions ◽

Volcanic Field ◽

Explosive Eruptions ◽

Human Populations ◽

Mass Wasting ◽

Geological Processes ◽

Research Activities

The Christiana–Santorini–Kolumbo volcanic field in the South Aegean Sea (Greece) is one of the most important in Europe, having produced more than 100 explosive eruptions in the last 400,000 years. Its volcanic centers include the extinct Christiana Volcano and associated seamounts, Santorini caldera with its intracaldera Kameni Volcano, Kolumbo Volcano, and 24 other submarine cones of the Kolumbo chain. Earthquakes, volcanic eruptions, submarine mass wasting, neotectonics and gas releases from these centers pose significant geohazards to human populations and infrastructures of the Eastern Mediterranean region. Defining the geological processes and structures that contribute to these geohazards will provide an important framework to guide future monitoring and research activities aimed at hazard mitigation.

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Soft-bottom sipunculans in Izmir Bay (Aegean Sea, eastern Mediterranean)

Zootaxa ◽

10.11646/zootaxa.2136.1.3 ◽

2009 ◽

Vol 2136 (1) ◽

pp. 40-48 ◽

Cited By ~ 4

Author(s):

SERMIN AÇIK

Keyword(s):

Eastern Mediterranean ◽

Aegean Sea ◽

Posidonia Oceanica ◽

Soft Bottom ◽

Muddy Sand ◽

Izmir Bay ◽

Ecological Characteristics

This paper deals with the sipunculan species distributed in Izmir Bay (Aegean Sea, eastern Mediterranean). Benthic samples were taken at 29 stations between 1998 and 2001 at depths ranging from 8 to 77 m. Six species and 200 individuals belonging to three families were found. Aspidosiphon (A.) mexicanus is newly recorded from Izmir Bay. The majority of specimens were found on a sandy-mud substratum (42%), followed by sand (35%), muddy-sand (19%) and sand (3%), respectively. Among the habitats, Posidonia oceanica and muddy-sand were represented by the highest numbers of species (4 species), followed by sandy-mud (3 species), and sand (2 species). The densities of the species at sampling stations were determined and compared seasonally, based on the data collected in 2001. Brief descriptions of the species and their distributional, reproductive and ecological characteristics are given.

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