Studies on the ecology of some species of sargassum

The species of Sargassum are abundant among the brown algae occurring along the Indian shores and these are the chief sources for the extraction of alginic acids, food, fodder and fertilizer.At present Ecological studies were made on three species of Sargassum growing along the Visakhapatnam and nearby localities. Data on the seasonal changes in growth collected on S.vulgare, S.ilicifolium and S.polycystum were expressed in terms of mean length of the fronds.Data obtained on the mean length of the fronds indicate that initiate the growth from March or April and attain the maximum height between November and December/January every year. Maximum growth was observed in the germ lings of S.vulgare and S.ilicifolium at photon flux densities of 18 and 36µ E m-2s-l.From this study on different factors, it can be concluded that the submerged condition of fronds, photon flux density of 9 µ E m-2s-1 ,salinities around normal sea water(30 0/00)and temperatures around 25°C are favourable for maximum oospores shedding, germination and growth of S.vulgare and S.ilicifolium.These experimental findings closely agree with the environmental conditions existing in the habitat of the Visakhapatnam coast.