Editing Reef (section)

=== Artificial ===
{{main|Artificial reef}}
An artificial reef is a human-created underwater structure, typically built to promote [[Marine biology#Reefs|marine life]] in areas with a generally featureless bottom, to control erosion, block ship passage, block the use of [[trawling]] nets,<ref name="Gray 2018" /> or improve [[surfing]].<ref name="Bournemouth Echo" />

Many reefs are built using objects that were built for other purposes, for example by sinking oil rigs (through the [[Rigs-to-Reefs]] program), [[Sinking ships for wreck diving sites|scuttling ships]], or by deploying [[rubble]] or [[construction debris]]. Other artificial reefs are purpose built (e.g. the [[The Reef Ball Foundation|reef balls]]) from [[Polyvinyl chloride|PVC]] or concrete. Shipwrecks become artificial reefs on the seafloor. Regardless of construction method, artificial reefs generally provide stable hard surfaces where [[algae]] and invertebrates such as [[barnacle]]s, corals, and [[oyster]]s attach; the accumulation of attached marine life in turn provides intricate structure and food for [[biocoenosis|assemblages]] of fish.