Tara Duggan, SAN FRANCISCO CHRONICLE
Eelgrass, a plant that grows in “underwater meadows” along the California coast and emerges like a floating carpet at low tide, is already known to be an important habitat for fish, birds and baby Dungeness crabs. It turns out it can also reduce seawater’s acidity back to preindustrial levels, creating refuges for animals who can’t tolerate that byproduct of climate change.
That’s the conclusion of a six-year study published recently by the UC Davis Bodega Marine Laboratory. It showed eelgrass meadows in seven California locations decreased ocean acidity by up to 30%. Because acidification, the result of the ocean absorbing increasing amounts of carbon dioxide from the atmosphere, has increased by 30% due to climate change, the plant has the ability to reverse the effects in its habitat.
The report, published in the journal Global Change Biology, is the most extensive study to show seagrass’ long-term ability to ameliorate ocean acidification. Its authors say it shows the importance of protecting seagrass meadows, which have shrunk in number and size globally because of pollution and development, so they may support wildlife as well as the production of farmed oysters, mussels and abalone.
“Because these systems are on the decline in many areas around the world, I would like this research to support many seagrass restoration efforts,” said lead author Aurora M. Ricart of the Bigelow Laboratory for Ocean Sciences in Maine, who was doing postdoctoral research at the Bodega Marine Lab during the study.