Led by CIM researcher Beatriz Mouriño, the project will study in particular the Pontevedra estuary, which presents higher and more persistent toxicity.
A group of researchers from the Marine Research Center of the University of Vigo has just launched a new project that aims to understand the productivity of the Rías Baixas and analyze the causes of episodes of toxicity. Named Magic (Modelling and Analysis of phytoplankton Growth in the estuaries: understanding productIvity and harmful algae Changes), this work is funded by the Ministry of Science, Innovation and Universities within the call for Knowledge Generation Projects 2024.
Magic has a budget of 225,000 euros and will last three years. The project is led by Beatriz Mouriño Carballido, researcher in the Biological Oceanography Group, and has the participation of Carlos Souto (Department of Applied Physics) and Marta Sestelo and Nora Villanueva (Department of Statistics and Operations Research). In addition, national and international institutions such as the Instituto de Investigación Mariñas-CSIC (Vigo), the Southampton Oceanographic Centre and the Plymouth Marine Laboratory, together with the Instituto Português do Mar e da Atmosfera, collaborate.
As Mouriño explains, the project got underway this September and its objective is to “unravel the factors that explain the extraordinary productivity of the Rías Baixas and the processes that favor the appearance of harmful algae blooms (HABs), a phenomenon that every year forces the temporary closure of rafting areas due to the accumulation of toxins.” These episodes of toxicity have a strong impact on the aquaculture sector, given that Galicia is the main mussel producer in Europe and the second in the world, only behind China.
The Magic project will focus in particular on the Pontevedra estuary, to study why it presents higher and more persistent levels of toxicity than other Galician estuaries. To do this, the researchers will combine oceanographic observations, satellite data analysis and monitoring, artificial intelligence techniques and numerical modeling. The aim will be to “understand how environmental and hydrodynamic factors influence the productivity and proliferation of harmful species such as Dinophysis.
As Beatriz Mouriño explains, this new research is a natural continuation of the Remedios project, within the framework of which an international team, also led by the UVigo researcher, developed several studies and lines of work to analyze the factors that trigger the growth of phytoplankton and the importance of the mixture of the different layers that form the oceans.
In search of the keys to the productivity of estuaries
The Galician estuaries, thanks to the upwelling phenomenon, are one of the most productive places on the planet and the Galician fishing and aquaculture industry represents a key component of the European blue economy. But despite their high productivity, explain the researchers from the Biological Oceanography Group, “we have incomplete knowledge about the temporal and spatial variability of phytoplankton activity in the region and the forcing mechanisms”. Previous studies have revealed the existence of an inverse pattern between the long-term variability of chlorophyll-a and the duration of upwelling events and this variability coincides with the temporal variability of the North Atlantic Oscillation during winter. These results suggest that long-term trends in estuarine productivity could be controlled by regional-scale ocean-atmosphere interaction processes that influence the duration of upwelling pulses. As Mouriño details, “previous observations in the Pontevedra estuary have shown that the rapid response of phytoplankton to wind forcing, three times faster than the platform, could explain the greater productivity of the estuaries compared to the adjacent platform”. But although the four estuaries share certain characteristics, they also present significant morphological differences and, as a consequence, “there could be variations between the estuaries in the hydrodynamic response time to wind forcing and in the duration of upwelling pulses and the researchers propose that these differences cause variability in primary production between the estuaries”.
Harmful algal blooms
The other leg of the project is the study of the factors that drive the formation of harmful algal blooms (HABs), which threaten the economic sustainability of shellfish production in the estuaries. At the moment, the mechanisms responsible for the persistence of Dinophysis cells and AO toxins are unknown, but previous studies suggest a possible relationship between the accumulation of harmful species and the formation of thin phytoplankton layers (CFF). “Numerical simulations indicate that the values of turbulent energy production in the Pontevedra estuary are lower than in Vigo and a lower production of turbulent kinetic energy and an increase in stratification could favor the greater persistence of CCF in the Pontevedra estuary”. To verify these hypotheses, the researchers propose a multidisciplinary approach that combines data analysis from monitoring and remote sensing programs; observations made in previous campaigns such as those developed in the Remedios project; advanced statistical techniques; and numerical simulations using the Croco-Pisces oceanographic model.
To address the risk of harmful algal blooms, the team will develop a comprehensive list of possible environmental scenarios that favor their formation in estuaries and this predictive framework will facilitate the identification of high-risk conditions, informing early warning systems and contributing to effective mitigation strategies that minimize ecological and economic impacts.
Two job opportunities
Within the framework of the project, the CIM-UVigo offers several employment opportunities, specifically a four-year FPI predoctoral contract and a 20-month postdoctoral contract. For the first, CVs can be submitted until November 3 and for the second until October 20.
The CIM holds the CIGUS certification from the Regional Government of Galicia, which attests to the quality and impact of its research, and its activities are co-financed by the European Union through the 2021–2027 FEDER Program.
Source: DUVI
