Trends in sessile epibiotic biomass on an artificial reef.

The Poole Bay Artificial Reef Project (PBAR) monitored the development of the first stabilised coal-waste artificial reef in the UK. This study documents the biomass of the sessile and mobile epibiota on this sublittoral reef, at approximately monthly intervals. following its deployment in June 1989. Biomass determinations were made to a constant weight at 80°C (dry weight) and 600°C (ash-free dry weight) following decalcification in 6% HCI. In general the epibiotic biomass from the concrete reef blocks was greater than that from the fly ash blocks.
The epibiotic biomass (g AFDW m-2) on PBAR was compared to that found at other sites in the UK, both on stabilised coal-waste slabs and tiles and on a natural reef. The biomass of the sessile epibiota from the PBAR blocks compared well with that on a local natural reef, but was low compared with that found on free-standing slabs at the PBAR site and tiles in the littoral zone.
The epibiotic biomass on the bases of the free-standing slabs was found to be very much greater than that from both the tops of these slabs and from any facial orientation of the reef blocks.