Distribution of Synechococcus and Prochlorococcus in the central Adriatic Sea

Abstract

        The abundance of Synechococcus and Prochlorococcus were determined at twenty-one stations located along the eastern coast of the central and southern Adriatic and at three stations located in the open central Adriatic Sea. Synechococcus abundance ranged from 10² to 10⁵ cells mL^-1 in the coastal area, and from 10³ to 10⁴ cells mL^-1 in the open sea Prochlorococcus abundance in the coastal area ranged from 0 to 10⁴ cells mL^-1 and from 10³ to 10⁴ cells mL^-1 in the open sea. The seasonal distribution of Synechococcus and Prochlorococcus mostly showed an increase in abundance during the warmer period and a decrease during winter. The highest abundance of Synechococcus was found in Kaštela Bay with values at 4.6 x 10⁵ cells mL^-1, while the highest abundance of Prochlorococcus was determined in the Šibenik area and recorded as 7.1 x 10⁴ cells mL^-1 Synechococcus was found to be more abundant than Prochlorococcus in most cases. The abundance of Synechococcus was influenced more by temperature than nutrient availability. The abundance of Prochlorococcocus was influenced by nutrient availability and the movement of water masses more than by HNF.