Seasonal variation in elemental composition of Stoechospermum marginatum (Ag.) Kutz and Sargassum wightii (Greville Mscr.) J.G. Agardh in relation to chemical composition of seawater

Seasonal variation in elemental composition of Stoechospermum marginatum and Sargassum wightii collected from Mandapam, Gulf of Mannar was studied over a period of 1 year from May 2006 to February 2007 at 3 months interval. The physico-chemical parameters of water such as air temperature (°C), surface water temperature (°C), turbidity (NTU), salinity (‰) and water pH were also made. Significant seasonal variation in the elemental composition of the two species was observed. These were correlated to the seawater chemistry. The accumulation factor of certain ions by the algae is also discussed. Intake of more minerals was accumulated in S. wightii during summer season.