Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-22T17:32:50.682Z Has data issue: false hasContentIssue false
  • English
  • Français

Summer mesozooplankton assemblages in the north-eastern Aegean Sea: the influence of Black Sea water and an associated anticyclonic eddy

Published online by Cambridge University Press:  02 June 2010

Stamatina Isari ,
Stylianos Somarakis ,
Epaminondas D. Christou  and
Nina Fragopoulu
Stamatina Isari*
Affiliation:
Laboratory of Zoology, Department of Biology, University of Patras, 26500 Rio, Patras, Greece
Stylianos Somarakis
Affiliation:
Hellenic Centre for Marine Research, PO Box 2214, 71003 Heraklion, Crete, Greece
Epaminondas D. Christou
Affiliation:
Hellenic Centre for Marine Research, PO Box 712, 19013 Anavissos, Athens, Greece
Nina Fragopoulu
Affiliation:
Laboratory of Zoology, Department of Biology, University of Patras, 26500 Rio, Patras, Greece
*
Correspondence should be addressed to: S. Isari, Hellenic Centre for Marine Research, PO Box 2214, 71003 Heraklion, Crete, Greece email: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The north-eastern Aegean Sea (NEA) is a marine system of high hydrological complexity, principally induced by the inflow and subsequent advection of the low salinity (<30) Black Sea water (BSW). This water mass occupies the upper layer (~0–20 m) of the NEA and plays a key role in the determination of circulation patterns and the generation of various frontal and eddy structures. Here we are concerned with the examination of mesozooplankton assemblages in the NEA during the thermal stratification period (July 2004) in two discrete sampling layers: (a) Layer 1 (from the base of halocline to the surface: ~0–20 m) which is directly influenced by BSW; and (b) the deeper ~20–50 m layer (Layer 2). Our main objective was to assess the response of mesozooplankton to the BSW and the associated hydrological structures. In July 2004, the BSW was mainly restricted in the eastern part of the NEA where it was entrapped in a ~50-km wide anticyclonic gyre (Samothraki gyre). A marked spatial differentiation in mesozooplankton assemblage structure, significantly related to this hydrodynamic partitioning, was detected in Layer 1. Sampling sites under the direct influence of low salinity–high temperature gyre waters were characterized by a considerably higher mesozooplankton stock than the remaining area, mainly due to the outstanding numerical dominance of the cladoceran species Penilia avirostris. Copepods displayed notably low densities within the gyre and low species diversity, the calanoid Temora stylifera was the only abundant species. The mesozooplankton community outside the gyre zone shifted towards lower levels of total abundance, with a lesser contribution of cladocerans and an increase in the importance of small-sized copepods (e.g. Acartia clausi, Paracalanus parvus, copepodites of Oithona spp. and Clausocalanus spp.). In the subsurface layer (Layer 2), the mesozooplankton community also exhibited spatial heterogeneity which could be hardly explained by variability in environmental parameters. The periphery of the anticyclone below the halocline was distinguished from the remaining neritic area, presenting markedly high mesozooplankton productivity and distinct group composition. An inverse pattern in the mesozooplankton stock vertical distribution was observed at the periphery of the gyre (Layer 2> Layer 1) comparative to the remaining sites (Layer 1 > Layer 2), which was mainly due to unusually high concentrations of surface-living zooplankters below the halocline. The latter could be explained in terms of expected water flow patterns in an anticyclonic eddy.

Keywords

mesozooplanktoncommunity compositiondistribution patternseddyeastern Mediterranean
Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 91 , Issue 1 , February 2011 , pp. 51 - 63
Copyright
Copyright © Marine Biological Association of the United Kingdom 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alcaraz, M., Calbet, A., Estrada, M., Marrasé, C., Saiz, E. and Trepat, I. (2007) Physical control of zooplankton communities in the Catalan Sea. Progress in Oceanography 74, 294–312.CrossRefGoogle Scholar
Atienza, D., Saiz, E., Skovgaard, A., Trepat, I. and Calbet, A. (2008) Life history and population dynamics of the marine cladoceran Penilia avirostris (Branchiopoda: Cladocera) in the Catalan Sea (NW Mediterranean). Journal of Plankton Research 30, 345–357.CrossRefGoogle Scholar
Bakun, A. (2006) Fronts and eddies as key structures in the habitat of marine fish larvae: opportunity, adaptive response and competitive advantage. Scientia Marina 70, 105–122.CrossRefGoogle Scholar
Boucher, J. (1984) Localization of zooplankton populations in the Ligurian marine front: role of ontogenic migration. Deep-Sea Research 31, 469–484.CrossRefGoogle Scholar
Broglio, E., Saiz, E., Calbet, A., Trepat, I. and Alcaraz, M. (2004) Trophic impact and prey selection by crustacean zooplankton on the microbial communities of an oligotrophic coastal area (NW Mediterranean Sea). Aquatic Microbial Ecology 35, 65–78.CrossRefGoogle Scholar
Cabal, J., Gonzáles-Nuevo, G. and Nogueira, E. (2008) Mesozooplankton species distribution in the NW and N Iberian shelf during spring 2004: relationship with frontal structures. Journal of Marine Systems 72, 282–297.CrossRefGoogle Scholar
Clarke, K.R. and Warwick, R.M. (1994) Change in marine communities: an approach to statistical analysis and interpretation. Plymouth: Natural Environment Research Council, UK.Google Scholar
Di Capua, I. and Mazzocchi, M.G. (2004) Population structure of the copepods Centropages typicus and Temora stylifera in different environmental conditions. ICES Journal of Marine Science 61, 632–644.CrossRefGoogle Scholar
Fernández de Puelles, M.L., Valencia, J., Jansá, J. and Morillas, A. (2004) Hydrographical characteristics and zooplankton distribution in the Mallorca channel (Western Mediterranean): spring 2001. ICES Journal of Marine Science 61, 654–666.CrossRefGoogle Scholar
Gaudy, R. and Youssara, F. (2003) Variations of zooplankton metabolism and feeding in the frontal area of the Alboran Sea (western Mediterranean) in winter. Oceanologica Acta 26, 179–189.CrossRefGoogle Scholar
Halsband-Lenk, C., Nival, S., Carlotti, F. and Hirche, H.J. (2001) Seasonal cycles of egg production of two planktonic copepods, Centropages typicus and Temora stylifera, in the north-western Mediterranean Sea. Journal of Plankton Research 23, 597–609.CrossRefGoogle Scholar
Hernández-León, S., Almeida, C., Gomez, M., Torres, S., Montero, I. and Portillo-Hahnfeld, A. (2001) Zooplankton biomass and indices of feeding and metabolism in island-generated eddies around Gran Canaria. Journal of Marine Systems 30, 51–66.CrossRefGoogle Scholar
Hosie, G.W. and Cochran, T.G. (1994) Mesoscale distribution patterns of macrozooplankton communities in Prydz bay, Antarctica—January to February 1991. Marine Ecology Progress Series 106, 21–39.CrossRefGoogle Scholar
Ianora, A. and Poulet, S.A. (1993) Egg viability in the copepod Temora stylifera. Limnology and Oceanography 38, 1615–1626.CrossRefGoogle Scholar
Isari, S., Ramfos, A., Somarakis, S., Koutsikopoulos, C., Kallianiotis, A. and Fragopoulu, N. (2006) Mesozooplankton distribution in relation to hydrology of the Northeastern Aegean Sea, Eastern Mediterranean. Journal of Plankton Research 28, 241–255.CrossRefGoogle Scholar
Isari, S., Psarra, S., Pitta, P., Mara, P., Tomprou, M.O., Ramfos, A., Somarakis, S., Tselepides, A., Koutsikopoulos, C. and Fragopoulu, N. (2007) Differential patterns of mesozooplankters' distribution in relation to physical and biological variables of the northeastern Aegean Sea (eastern Mediterranean). Marine Biology 151, 1035–1050.CrossRefGoogle Scholar
Isari, S., Fragopoulu, N. and Somarakis, S. (2008) Interannual variability in horizontal patterns of larval fish assemblages in the northeastern Aegean Sea (eastern Mediterranean) during early summer. Estuarine, Coastal and Shelf Science 79, 607–619.CrossRefGoogle Scholar
Isla, J.A., Ceballos, S., Huskin, I., Anadón, R. and Álvarez-Marqués, F. (2004) Mesozooplankton distribution, metabolism and grazing in an anticyclonic slope water oceanic eddy (SWODDY) in the Bay of Biscay. Marine Biology 145, 1201–1212.CrossRefGoogle Scholar
Kiørboe, T. (1993) Turbulence, phytoplankton cell size and the structure of pelagic food webs. Advances in Marine Biology 29, 1–72.CrossRefGoogle Scholar
Kruskal, J.B. and Wish, M. (1978) Multidimensional scaling. Beverly Hills, CA: Sage Publications.CrossRefGoogle Scholar
Lalli, C.M. and Parsons, T. (2002) Biological oceanography: an introduction, 2nd edition. Great Britain: The Open University, Butterworth-Heinemann.Google Scholar
Le Fèvre, J. (1986) Aspects of the biology of frontal systems. Advances in Marine Biology 23, 163–299.CrossRefGoogle Scholar
Mackas, D.L., Tsurumi, M., Galbraith, M.D. and Yelland, D.R. (2005) Zooplankton distribution and dynamics in a North Pacific Eddy of coastal origin: II. Mechanisms of eddy colonization by and retention of offshore species. Deep-Sea Research Part II: Topical Studies in Oceanography 52, 1011–1035.CrossRefGoogle Scholar
Mazzocchi, M.G., Christou, E.D., Fragopoulu, N. and Siokou-Frangou, I. (1997) Mesozooplankton distribution from Sicily to Cyprus (Eastern Mediterranean): general aspects. Oceanologica Acta 20, 521–535.Google Scholar
Mazzocchi, M.G., Buffoni, G., Carotenuto, Y., Pasquali, S. and Ribera d'Alcalá, M. (2006) Effects of food conditions on the development of the population of Temora stylifera: a modelling approach. Journal of Marine Systems 62, 71–84.CrossRefGoogle Scholar
Molinero, J.C., Ibanez, F., Souissi, S., Bosc, E. and Nival, P. (2008) Surface patterns of zooplankton variability detected by high frequency sampling in the NW Mediterranean: role of density fronts. Journal of Marine Systems 69, 271–282CrossRefGoogle Scholar
Omori, M. and Ikeda, T. (1984) Methods in marine zooplankton ecology. New York: John Wiley & Sons.Google Scholar
Owen, R. (1981) Fronts and eddies in the sea: mechanisms, interactions and biological effects. In Longhurst, A.R. (ed.) Analysis of marine ecosystems. London: Academic Press, pp. 197–233.Google Scholar
Paffenhöfer, G.A. (1998) On the relation of structure, perception and activity in marine planktonic copepods. Journal of Marine Systems 15, 457–473.CrossRefGoogle Scholar
Paffenhöfer, G.A. and Mazzocchi, M.G. (2003) Vertical distribution of subtropical epiplanktonic copepods. Journal of Plankton Research 15, 1139–1156.CrossRefGoogle Scholar
Pancucci-Papadopoulou, M.A., Siokou-Frangou, I., Theocharis, A. and Georgopoulos, D. (1992) Zooplankton vertical distribution in relation to the hydrology in the NW Levantine and the SE Aegean Seas (spring 1986). Oceanologica Acta 15, 365–381.Google Scholar
Pinca, S. and Dallot, S. (1995) Meso- and macrozooplankton composition patterns related to hydrodynamic structures in the Ligurian Sea (Trophos-2 experiment, April–June 1986). Marine Ecology Progress Series 126, 49–65.CrossRefGoogle Scholar
Riandey, V., Champalbert, G., Carlotti, F., Taupier-Letage, I. and Thibault-Botha, D. (2005) Zooplankton distribution related to the hydrodynamic features in the Algerian Basin (western Mediterranean Sea) in summer 1997. Deep-Sea Research Part I: Oceanographic Research Papers 52, 2029–2048.CrossRefGoogle Scholar
Robinson, A.R. (1983) Overview and summary of eddy science. In Robinson, A.R. (ed.) Eddies in marine science. Berlin and Heidelberg: Springer-Verlag, pp. 1–15.CrossRefGoogle Scholar
Shannon, C.E. and Weaver, W. (1963) The mathematical theory of communication. Urbana, IL: Urbana University Press.Google Scholar
Siokou-Frangou, I. (1996) Zooplankton annual cycle in a Mediterranean coastal area. Journal of Plankton Research 18, 203–223.CrossRefGoogle Scholar
Siokou-Frangou, I., Christou, E.D., Fragopoulu, N. and Mazzocchi, M.G. (1997) Mesozooplankton distribution from Sicily to Cyprus (Eastern Mediterranean): II. Copepod assemblages. Oceanologica Acta 20, 537–548.Google Scholar
Siokou-Frangou, I., Papathanassiou, E., Lepretre, A. and Serge, F. (1998) Zooplankton assemblages and influence of environmental parameters on them in a Mediterranean coastal area. Journal of Plankton Research 20, 847–870.CrossRefGoogle Scholar
Weikert, H. and Koppelmann, R. (1993) Vertical structural patterns of deep-living zooplankton in the NE Atlantic, the Levantine Sea and the Red Sea: a comparison. Oceanologica Acta 16, 163–177.Google Scholar
Zar, J.H. (1999) Biostatistical analysis, 4th edition. Upper Saddle River, NJ: Prentice-Hall.Google Scholar
Zervakis, V. and Georgopoulos, D. (2002) Hydrology and circulation in the North Aegean (eastern Mediterranean) throughout 1997 and 1998. Mediterranean Marine Science 3, 5–19.CrossRefGoogle Scholar
Zervoudaki, S., Nielsen, T.G., Christou, E.D. and Siokou-Frangou, I. (2006) Zooplankton distribution and diversity in a frontal area of the Aegean Sea. Marine Biology Research 2, 149–168.CrossRefGoogle Scholar
Zervoudaki, S., Christou, E.D., Nielsen, T.G., Siokou-Frangou, I., Assimakopoulou, G., Giannakourou, A., Maar, M., Pagou, K., Krasakopoulou, E., Christaki, U. and Moraitou-Apostolopoulou, M. (2007) The importance of small-sized copepods in a frontal area of the Aegean Sea. Journal of Plankton Research 29, 17–338.CrossRefGoogle Scholar
Zodiatis, G. and Balopoulos, E. (1993) Structure and characteristics of fronts in the North Aegean Sea. Bolletino Oceanologia Teorica ed Applicata 11, 113–124.Google Scholar