“Subterranean estuaries” may be critical in managing sustainable fishing and aquaculture, according to new research.
Subterranean estuaries may be invisible to the naked eye, but may be very important in the ecology of coastal systems, the research by Trinity College Dublin and the Marine Research Institute of the Spanish Research Council in Vigo, Galicia, Spain has found.
They may also filter pollutants – some of which have been slowly travelling to sea for decades having leached from agricultural soils.
The researchers uncovered subterranean estuaries in the Ria de Vigo in Galicia -one of the most productive coastal ecosystems in Europe and leader in bivalve production for human consumption.
They assessed their importance to the coastal environment, and estimated that almost 25% of the continental freshwater discharged to the Ria de Vigo comes from these subterranean sources.
“Bivalve aquaculture is a strategic, expanding sector in Irish sustainable development and features highly in the national plans to diversify food production”, Carlos Rocha, professor in environmental change at Trinity College, Dublin’s school of natural sciences said.
“While our work was conducted in the Ria de Vigo, this area was carefully selected because of its capability to support aquaculture and its biogeographic similarity to parts of the Irish coastline,” Prof Rocha said.
“These subterranean estuaries have a high capability to filter out pollutants, like fertilisers, from freshwater. Given the extent to which they supply large ecosystems with incoming freshwater, they have a much more important role to play than many would have believed,” he added.
NUI Galway has previously conducted research on subterranean streams in the limestone-rich Burren area of Co Clare and their influence on Galway Bay.
The new research has just been published in open access in Frontiers in Marine Science (https://doi.org/10.3389/fmars.2021.626813) and Limnology and Oceanography (https://doi.org/10.1002/lno.11733).