Seagrass beds are ecologically critical shallow-water ecosystems, as they play an important role in all coastal processes, making them critical for maintaining populations of commercially important species and playing a key role in the sustainability of small-scale fisheries. However, they are not only experiencing a rapid decline, with a loss of around 7% of their global distribution each year, but also they are often left off the conservation agenda of governments and international organizations. Now, under the ZEUS project, funded by the Ministry of Science, Innovation and Universities with a budget of € 211,750, research staff from the Coastal Ecology group belonging to the Marine Research Center of the University of Vigo, will evaluate the importance of the Zostera noltei meadows as a hatchery area and habitats for juveniles and reproductive adults of three species of commercial clams (carpetshells, japonic and fine) and as mitigators of heat waves and sudden fluctuations of salinity. “We also want to value the importance of conserving these meadows, which often conflict with the interests of shellfish, since one of the usual practices is the elimination of the Zostera in these areas”, Celia Olabarría and Elsa Vázquez highlight, main researchers of the project.
The objective is to provide information that facilitates a comprehensive and efficient management of shellfish resources in intertidal beds of Zostera noltei in a context of climate change in which the extreme events will be more frequent and intense. “They are areas for the breeding, maintenance and refuge of juveniles of various species of vertebrates and invertebrates and they intervene in the recycling of nutrients and in the stabilization of sediment. They contribute to carbon sequestration, to the mitigation of climate change and to the resilience of coastal ecosystems”, they explain. Despite all these advantages, “due to anthropogenic impacts, many of the phanerogams meadows are in decline. In Galicia, the harvesting of shellfish and the conservation of Zostera beds can come into conflict, since it is usual to eliminate the plant considering that it interferes with shellfish activities and, that areas with a high density of plants have little shellfish resource”.
Economic value of different seagrass beds
The project is completed with a socio-economic aspect, since it will try to estimate the economic value of the different seagrass beds according to their function as hatchery and / or habitat of adult clam specimens and their ability to buffer adverse environmental conditions derived from extreme events.
For all this, the research group has the collaboration of the fishermen’s guilds and, their technical assistance from Cambados, Noia and Combarro, who bring their perspective of the problem between shellfishing and the maintenance of the Zostera meadows. Moreover, they help the experimental part of the project facilitating access and maintenance of the experiments in the shellfish banks of Sarrido (Cambados), Testal (Noia) and Combarro and providing juveniles of the clam species for laboratory experiments. They also contribute with workshops and surveys that are carried out within the project within its socio-economic aspect.
EcoCost also collaborates in this project with the Biodiversity and Conservation Area of the Rey Juan Carlos University and with senior researchers from the Department of Biological Sciences of the University of South Carolina. The socio-economic part is led by Sebastián Villasante, from the Department of Applied Economics at the University of Santiago de Compostela.