SCOTLAND’S marine coral reef systems may be more sensitive to carbon dioxide than previously thought, according to research.

Scientists argued such areas could be facing irreparable damage as a result of CO² “pulses” created by industrial activities, land run-off or natural tidal processes.

Until now, the effect of high CO² had only been tested on individual plants and animals, with very little known about how whole marine ecosystems respond to sudden influxes of the gas.

However, a team from Heriot-Watt University and Glasgow University conducted a four-day experiment at Loch Sween, on the west coast of Scotland, to measure the community response to short-term CO² exposure. The team pumped water enriched with carbon dioxide into chambers placed over the coralline algal ecosystem and monitored the response before, during, and after CO² exposure.

Results revealed that acute CO² exposure led to net dissolution; calcified organisms like the coralline algae and star fish were dissolving, it was found.

Dr Heidi Burdett, of Heriot-Watt’s Lyell Centre For Earth And Marine Science And Technology, said: “Coralline algal ecosystems can be found in all the world’s coastal oceans and are particularly common along the west coast of Scotland. Since coralline algae are highly calcified, we knew they would probably be quite sensitive to CO2.

“These beds have significant ecological and economical value. In Scotland, they act as nurseries for important catches like scallops, cod and pollock.

“We found there was a rapid, community-level shift to net dissolution, meaning that within that community, the skeletons of calcifying organisms like star fish and coralline algae were dissolving.

“If you think of pulses of carbon dioxide being carried on the tide to a particular site, it’s like a flash flood of CO².

“Our continued monitoring of the site directly after the CO² exposure found recovery was comparably slow, which raises concern about the ability of these systems to bounce back after repeated acute CO² events.”

Dr Burdett’s team have called for further research into how marine ecosystems respond to CO² exposure, urging policymakers to take the results into account.