Studies on the Management of Sargassum (Fucales, Phaeophyta) Bed in Bolinao, Pangasinan, Philippines

Algae > Volume 8(2); 1993 > Article

Algae 1993;8(2): 249-257.

Gaviono C. Trono, Jr., Grace L. Tolentino

Marine Science Institute, College of Science, University of the Philippines Diliman

ABSTRACT

The problem of over-exploitation/depletion of natural stocks of Sargassum is presently a major issue between fishermen and seaweed gatherers in areas where the seaweed is commercially harvested. Studies on the seasonality of biomass production, alginate yield and viscosity, reproductive periodicity and regeneration responses of the beds to harvest pressures were conducted to gather information which can serve as basis for the formulation of a management scheme for the resource. In general, biomass production of the bed followed an annual trend-low in February, gradually increasing and reaching peak in October to December or January with the subtidal bed producing higher biomass than the intertidal bed. Minor deviation from these trends occur when typhoons hit the area during the southwest monsoon months. Trend in the occurrence of fertile populations also generally follow trend in biomass production with minor intra-annual peaks which are more pronounced in subtidal portions of the beds. Over all, the alginate yields from biomass harvested from the subtidal beds were higher than those from intertidal beds. Monthly measurements of regrowth of thalli cut at the middle (50% harvest) and at their bases (100% harvest) were not significantly different (P

Key words: Sargassum, phenology, standing crop, alginate, reproductive periodicity, regeneration