PHENOLOGY OF GIGARTINA-SKOTTSBERGII (GIGARTINACEAE, RHODOPHYTA) IN ANCUD BAY, SOUTHERN CHILE

This study reports the variations in biomass and reproductive phenolog y in a natural bed of Gigartina skottsbergii over a period of a year a nd correlates these variations with the abiotic factors solar radiatio n, number of daylight hours, water temperature and salinity. The resul ts obtained show an annual production cycle with maximum biomass value s in spring-summer, correlated with high solar radiation and to a less er extent with salinity. Sexual reproduction was maximum in autumn-win ter, correlated with low temperature and short-day conditions. The pop ulation showed a large gametophytic dominance according to size and bi omass, which suggests that there is not ecological equivalence between the life history phases of the species. Finally, based on the results , a restriction of harvesting to spring-summer is suggested.