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Marine Biology

, Volume 151, Issue 3, pp 1035–1050 | Cite as

Differential patterns of mesozooplankters’ distribution in relation to physical and biological variables of the northeastern Aegean Sea (eastern Mediterranean)

  • S.  Isari
  • S.  Psarra
  • P.  Pitta
  • P. Mara
  • M. O. Tomprou
  • A. Ramfos
  • S. Somarakis
  • A. Tselepides
  • C. Koutsikopoulos
  • N. Fragopoulu
Research Article

Abstract

Mesozooplankton group composition was examined in the Northeastern Aegean Sea (NEA) over a grid of 30 stations sampled during July 2004. The surface water layer influenced by the low salinity Black Sea waters (BSW) is considered in this paper. We attempted to study horizontal distribution patterns of major mesozooplankters within a more comprehensive framework, taking into account not only hydrology but also available, concurrently collected data on lower trophic levels (autotrophic and microbial heterotrophic communities). BSW was mainly restricted in the eastern part of the surveyed area where it was entrapped in a ca. 50-km wide anticyclone (the “Samothraki” gyre). High Chlα concentrations, autotrophic biomass as well as abundance and biomass of mesozooplankton were associated with the BSW, with the highest values recorded inside the gyre as well as at its coastal northern periphery and the lowest values towards the western and offshore part of the surveyed area characterized by high salinity waters of Levantine origin. Among mesozooplankters, cladocerans (mainly Penilia avirostris) showed a high abundance within the gyre in contrast to the very low abundance of copepods and appendicularians. Low salinity-high temperature gyre waters were characterized by the dominance of cyanobacteria of the genus Synechococcus in autotrophic biomass and the significant contribution of heterotrophic nanoflagellates in microbial heterotrophic biomass. Based on existing knowledge on ecophysiological traits and prey size-spectra selectivity, we discuss the observed distribution patterns of major mesozooplankton groups in terms of ambient abiotic parameters and the possible biological interactions among these groups as well as with lower or upper trophic levels.

Keywords

Synechococcus Dissolve Organic Carbon Concentration Cladoceran Species Heterotrophic Nanoflagellates Mesozooplankton Community 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

The present study was supported by the EU project ANREC (QLRT-2001-01216). The authors wish to thank the captain and the crew of R/V ‘Aegaeo’ as well as all participant scientists for their support at sea. Thanks are also due to two anonymous referees for their advices and suggestions in the improvement of the manuscript.

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • S.  Isari
    • 1
  • S.  Psarra
    • 2
  • P.  Pitta
    • 2
  • P. Mara
    • 3
  • M. O. Tomprou
    • 2
    • 4
  • A. Ramfos
    • 1
  • S. Somarakis
    • 4
  • A. Tselepides
    • 2
  • C. Koutsikopoulos
    • 1
  • N. Fragopoulu
    • 1
  1. 1.Laboratory of Zoology, Department of BiologyUniversity of PatrasRioGreece
  2. 2.Hellenic Centre for Marine ResearchOceanography InstituteHeraklionGreece
  3. 3.Environmental Chemical Processes Laboratory, Department of ChemistryUniversity of CreteVoutes, HeraklionGreece
  4. 4.Department of BiologyUniversity of CreteVoutes, HeraklionGreece

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