Science-To-Policy Tara Europa Lab Workshop in Marseille – Monitoring and Protecting the Land-Sea Interface

Tara in Marseille

On Friday, the 5th of April 2024, BlueRemediomics partners from Tara Ocean Foundation held a science-to-policy workshop on the topic “Innovative tools for monitoring and protecting the land-sea interface” in Marseille, France. As with previous Tara Europa Lab workshops, the event was organized as part of BlueRemediomics Outreach actions, in conjunction with the Traversing European Coastlines (TREC) expedition.

The TREC Methodology

Plankton plays an essential role in marine ecosystems, notably as the basis of the food chain, sequestering carbon and actively participating in the oxygenation of the oceans and the planet. The TREC (TRaversing European Coastlines) expedition, a collaboration between the Tara Océan Tara Foundation and EMBL (European Molecular Biology Laboratory), aims to characterize these land-sea interactions on a European scale. The study includes the analysis of both preserved and degraded areas, such as harbours and areas downstream from high concentrations of urban or agricultural activity, using a variety of gradients (time, salinity, pollution, etc.). Samples are taken both  at sea, using the schooner Tara, and on land, using EMBL trucks. In 2023, the study covered the Baltic and the North Sea, with a planned extension to the Mediterranean in 2024. This will enable a comparison to be made across the entire European coastline, to understand the impact of both natural environmental variations and those due to human activities, on the marine microbiome.

Workshop Outcomes

To kick off the workshop, Samuel Chaffron from Nantes University presented the Ocean Health Index (OHI), which is used in 220 ocean areas worldwide, although it does not provide specific information on the microbiome. The aim is therefore to integrate our knowledge of the marine microbiome into this tool to quantify the health of the oceans by developing indicators based on the data we have on the genes and genotypes of the marine microbiome, namely the Microbiome Health Index (MHI). This Microbiome Health Index is being established as part of Work Package 4 in BlueRemediomics.

Damien Eveillard (Nantes University) introduced a different indicator, currently under development, also aimed at using the marine microbiome to better monitor the health of the ocean: the KOPAs (Key Ocean Planktonic Areas) index. It identifies environmental niches – i.e. specific environmental conditions – where marine microbial species evolve and perform certain functions. This index could thus help to define and manage Marine Protected Areas (MPAs) in a more dynamic and interactive way, by mapping areas where plankton perform ecosystem services more intensively – such as the carbon pump, testifying to particularly rich biodiversity, or providing a life reserve for surrounding areas.

Both these indicators presented in the Tara Europa Lab Workshop use the microbiome to provide a finer capacity for observing and understanding the environment. Although highly promising, they are still in the development stage and need to be confronted with the extremely fine mesh required by coastal and littoral zone managers.

Integrating Land-Sea Strategy into Public Policy

The workshop highlighted the need for policy changes when measuring ocean health. Pierre Boissery (French Water Agency – in charge of all water quality and biodiversity surveys in marine and fresh-water ecosystems) spoke of the need to integrate the land-sea strategy into public policy, drawing on concrete examples such as the Calanques. He underlined the challenges posed by the complexity of the legal network, the multiplication of compulsory monitoring indicators that are sometimes not very informative, and the slowness of political decision-making in relation to the biological reality on the ground. He also stressed the importance of regional interaction and monitoring to ensure the effectiveness of protection measures.


International collaborations, the integration of contextual data, and the integration of the most advanced knowledge, including that on the marine microbiome, are key elements in responding to current and future environmental challenges, and in encouraging faster and more effective political decision-making on marine protection. The BlueRemediomics project aims to improve the understanding of the relationship between the marine microbiome and ocean health and address key ecosystem services enabled by marine microbes (carbon sequestration and aquaculture). By establishing a Microbiome Health Index (MHI) for monitoring marine environments, we will be better able to assess coastal anthropogenic impacts (e.g. urbanisation, aquaculture industry).