Cyprus eddy

Modern HPLC techniques allow characterisation of the eukaryotes by their pigment signatures. HPLC has demonstrated, that prymesiophytes dominated the eukaryotic group in the Cyprus Eddy in March 1992 whereas diatoms were rare. In 2001, dinoflagellates and coccolithophores dominated the eukaryotes (Psarra, personal communication). 

With the present lack of synoptic tools for surveying bacterial abundance, data on the abundance and production of heterotrophic bacteria in the Eastern Mediterranean are more sporadic than for phytoplankton chlorophyll and depend on discrete depth sampling and analysis. The data available are for the Cyprus Eddy in summer (Zohary Robarts, 1992) and in winter (Zohary etal., 1998), and in the Cretan Sea in March and September (van Wambeke etal., 2000), and a general survey of the Levantine Basin in fall (Robarts etal., 1996). Some additional data exists for the Western Mediterranean which will not be reviewed here. 

As has been noted above, the Eastern Mediterranean is characterised by many eddies and jets (POEM, 1992). Indeed there are almost no areas of the basin which are not part of some mesoscale feature or other (Fig. 4.3). Yet the nutrient distribution (Kress Herat, 2001) and many of the plankton features such as bacterial abundance and activity and chlorophyll content (Yacobi etal., 1995) seem to be nearly constant across large parts of the basin except for those locations where they intersect major and persistent mesoscale features (Fig. 4.5). Under those circumstances major changes in nutrient distribution and productivity can be seen. The Rhodes Gyre and the Cyprus Eddy (aka Shikmona Gyre) are permanent features which always have an effect on the local biogeochemistry and have been studied in some detail. 

Fig. 4.8 Seasonal nutrient distribution of the Cyprus Eddy (after Krom etal1992).

The most detailed studies of warm-core eddies have been carried out by Krom and co-workers on the Cyprus Eddy (aka Shikmona Gyre Krom etal., 1992, 1993 Zohary etal., 1998). It has also been the site of the recent CYCLOPS phosphate addition experiment which was designed to increase understanding of microbiological processes and nutrient cycling in the Eastern Mediterranean (Carbo etal., 2002). The Cyprus Eddy is a quasi-stationary warm-core feature situated south of Cyprus. It has been found both to the east and west of the Eratosthenes Seamount. It seems to remain stationary for several years and then move out probably to the northeast to be replaced with another similar feature from the southwest (Brenner etal., 1990). 

Cyprus warm-core (anti-cyclonic) eddy... 

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