Temporal variation in vegetative development of Caulerpa scalpelliformis (Chlorophyta) from Baleia beach, Ilha Grande bay (Rio de janeiro, brazil)

Abstract

Caulerpa scalpelliformis grows on rocky and sandy bottoms at different depths in Jacuacanga Cove, Ilha Grande Bay, where it can form dense patches. The invasive behavior of this and other species of Caulerpa is well documented in the literature. This study analyzed the variation of the vegetative development of C. scalpelliformis from Baleia Beach (23º01'63''S and 44º14'18''W) in Jacuacanga Cove, from June 2003 to September 2004, including plants from rocky and sandy substrates. Morphometric and dry weight data from the erect and prostrate portions were used. Plants were collected from 20 x 20 cm² plots (n=3), randomly positioned on the rocky boulders (≅1.5 m depth) and on contiguous sandy bottom (≅3.0 m depth). During the study period, C. scalpelliformis occurred on both substrates as a pseudo-perennial species, showing partial loss of the erect portions from winter to spring; the height and dry weight of the erect portions increased from summer to autumn on both substrates. The temporal variation of C. scalpelliformis vegetative development in Baleia Beach was similar to that described for the invasive C. racemosa and C. taxifolia from different geographical regions of the world.