ENVIRONMENTAL DESCRIPTION OF AN ARTIFICIAL REEF SITE IN GRAN-CANARIA (CANARY-ISLANDS, SPAIN) PRIOR TO REEF PLACEMENT

An artificial reef complex was built on the southern coast of Gran Can aria Island (Canary Islands), with the financial support of the Archip elago Autonomous Government, This artificial reef is composed of five separated units, each of them with different types of modular concrete blocks. Between November 1990 and March 1991, before the deposition o f the concrete blocks, an oceanographic and biological assessment of t he selected area was carried out which included oceanographic and SCUB A sampling at the artificial reef site, the coastal rocky bottom and a nearby sublittoral natural reef. The results obtained allowed us to m ake a bionomical chart of that coast and to characterize the entire ar ea as oligotrophic, in the oceanographic and biological sense. Nutrien t concentrations were low. Benthic communities were composed of differ ent species of green algae and few live invertebrates were observed. T he ichthyofauna was diverse, but with a low biomass.