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Individual study: The use of coal fly ash in concrete for marine artificial reefs in the southeastern Mediterranean: compressive strength, sessile biota, and chemical composition

Published source details

Kress N. (2002) The use of coal fly ash in concrete for marine artificial reefs in the southeastern Mediterranean: compressive strength, sessile biota, and chemical composition. ICES Journal of Marine Science, 59, S231-S237


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Create artificial reefs of different 3-D structure and material used Subtidal Benthic Invertebrate Conservation

A replicated, controlled study in 1996–1999 of 80 artificial reef blocks in the southeastern Mediterranean Sea, off the coast of Haifa, Israel (Kress et al. 2002) found that blocks created using coal fly ash (a cheap waste product) instead of sand had similar sessile invertebrate species richness and percentage cover as traditional blocks without coal fly ash, over 33 months following deployment. When compared to blocks made of traditional 0% coal fly ash, reef blocks made of either 40%, 60% or 80% coal fly ash had similar species richness (in 22 of 24 comparisons) and similar species cover (in 24 of 24 comparisons) (data not shown). In November 1996, blocks (20 × 20 × 40 cm) made of a mixture of concrete and coal fly ash were put on the seabed as artificial reefs at 18.5 m depth. There were four treatments: blocks with either 0%, 40%, 60% and 80% coal fly ash (20 blocks/treatment). Divers sampled two blocks/treatment at 3–4-month intervals for 33 months (10 sampling events). Invertebrates growing on each block side were identified and counted, and their percentage cover estimated.

(Summarised by Anaëlle Lemasson)