| With the purpose of determining if some effect exists on the tropical bentica community by the food introduction, the production of metabolic remainders of the fish and the food remainders like result of the aquaculture in open sea. A spatial and temporal characterization of the benthic macroinfauna was done in response to the installation of two cages for open ocean fish culture placed 28 m deep and located 3.2 km south of Isla Culebra, Puerto Rico. Bimonthly samplings (October 2002 to October 2003) were made to obtain sediment samples north, south, east, west and at center sites under each cage and in a control site. Nutrient concentration, organic matter content, and sediment texture were determined. The low nutrient concentration was constant over time and space; a significant increase in organic matter content was observed only in October 2003. The Shannon-Wiener Index indicated no significant change in the benthic community in relation to the impact of this system through the study year. The current speed (20-30 cm/s) and the associated fauna around the cages seem to play an important role avoiding pollution in the area selected for this type of aquaculture. |
