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Abstract

Starting in March 1997, fouling community colonization was compared on na artificila reef on the north coast of Rio de Janeiro.  Experimental rubber and concrete modules with panels were immersed 9 meters deep. Montthly, four replicate panels of each material were collected using a destructive point sampling technique.  After 12 months, 89 taxa were observed on both materials. Twenty-eight percent were exclusive to concrete and eighteen percent to rubber. Turnover values were similar on different substrata with increasing tendency up to the tenth month. Higher values in dry weight on concrete panels demonstrated a greater coloni zation intensity on this material. Balanus, Obelia Ostrea and Bougainvillia were predominant during the initial eight months on both substrata. Thereafter, increments in free space and colonization by algae were common on rubber panels, and Porifera, Gorgonacea and colonial Ascidiacea were commonly found on the concrete ones. Low structural differences occurred for successive immersion periods on both substrata because the most representative taxa did not suffer great changes until the eighth month (October 1997). After this period, structural similarity decreased significantly due to a greater instability of the community on rubber panels caused by its smooth surface, showing that concrete substrates with greater porosity and rugosity provide a more adequate surface for biofouling colonization.