Seasonal variations of abundance and biomass of picoplanktonic Synechococcus on the Yumurtalik-Sugözü coastline, Iskenderun bay

In this study, seasonal variations of picoplanktonic Synechococcus was investigated at eight stations located on the Yumurtalık-Sugözü coastal shelf area. Samplings were performed four times between September 2005 and July 2006. The abundance and carbon biomass of Synechococcus was examined. Phytoplankton biomass in terms of chlorophyll a concentrations was also determined. In addition, physicochemical parameters such as temperature, salinity and inorganic nutrients were measured to determine the influence of these parameters on Synechococcus dynamics. The lowest chlorophyll a value was determined as 0.16 ?g l-1 and the highest value was found as 1.61 ?g l-1. The abundance of Synechococcus was found in the range of 1.2-37.4x104 cells ml-1. Synechococcus carbon biomass was in the range of 0.48-30.9 ?gC l-1. At the end of the study, it was concluded that the abundance of Synechococcus increased in summer but they decreased in winter and spring in the study area. Key Words: Picophytoplankton, Synechococcus, Chlorophyll a, Nutrient, İskenderun Bay.