February 18, 2022 — Restoration efforts for kelp forests may be most effective in areas where the bedrock seafloor is highly contoured, research by Oregon State University suggests.
The findings, published today in the Proceedings of the National Academy of Sciences, are important because kelp, large algae with massive ecological and economic importance around the world, are under siege from environmental change and overgrazing by urchins.
The study, led by recent graduate Zachary Randell when he was an Oregon State doctoral student, shows that kelp forests in areas with ocean floor ruggedness – scientifically termed substrate complexity or surface rugosity – tend toward stability.
There were urchins in kelp forests growing in areas of high substrate complexity, but those urchins did not cause widespread destruction of kelp forests. One hypothesis is that substrate complexity retains “drift algae” – detached pieces of kelp and other algae – which urchins prefer to eat over live kelp, Randell said.