A Lab Study of the Si:N Ratio Variations of the Specific Composition of Phytoplankton

This study describes the changes in species composition of phytoplankton under different Si:N ratios from spring to summer of 2010 and 2011. For this purpose, natural Phytoplankton was cultured in mesocosmic experiments at two stations in the northern part of Latakia coastal water. The abundance of phytoplankton was measured, and the specific composition of phytoplankton was determined. Diatoms dominated during 2010 and 2011, while Dinoflagellates did not compete with diatoms during this study. The enrichment experiment affected the species composition of the diatoms themselves, where the species Pseudo-nitzschia pseudodelicatissima Schil and Leptocylindrus danicus Cleve dominated under different Si:N ratios.