The TREC expedition – “Traversing European Coastlines”, is travelling along the European coast, from the Baltic to the Mediterranean Sea, for the first time since it began in April 2023.

This week, an unprecedented European scientific project has its 27th stop in the Algarve on a journey to draw a map of the continent’s coastal ecosystems and understand the human impact on the oceans.

The TREC expedition – “Traversing European Coastlines”, which began in April 2023 and is scheduled to conclude in June next year, is travelling for the first time along the European coast, from the Baltic to the Mediterranean Sea, in an initiative led by the European Molecular Biology Laboratory (EMBL).

In Portugal, the expedition has already been to Porto and is now in the southern part of the country, chosen because it is the ‘border’ between the Atlantic Ocean and the Mediterranean Sea, Kiley Seitz, North American soil microbiologist and researcher at EMBL, explains.

“This is where we’re leaving the Atlantic [Ocean], and we’re starting to head toward the Mediterranean [Sea]. We’re trying to cover a lot of different gradients, and because we have this shift right here, we’re going to get a good view of the impact of water and land, how it is moved in and out of the ocean”, says the researcher.

This project, unprecedented on a European scale, analysing more than 120 locations in 46 areas of the continent, aims to study coastal ecosystems and how organisms respond to natural environmental factors and human impact at different scales.

The TREC expedition combines the collection of samples of soil, sediments, shallow waters and organisms by around a dozen researchers at each stop, on land and at sea, where a laboratory boat with its own technology is used.

The project’s first phase ends in November, with the next stop in Cádiz, in neighbouring Spain. The second phase runs from February to August 2024, travelling along the Mediterranean coast and culminating in Malta.

“There has never been a project like this. (…) It is something unprecedented, and we really hope that this will be a starting point for this type of large-scale data collection”, says the scientist during a guided tour of the mobile laboratory, one of three vehicles involved in the expedition, temporarily installed next to the Marine Sciences Centre of the University of the Algarve, one of the 70 local partners involved in the project.

In this mobile laboratory, which has an oven to dry the samples and storage space, only basic analyses are carried out, as all samples are sent to the EBML headquarters in Heidelberg, Germany, where further tests will be carried out.

Scientists also collect data on pollutants, antibiotics and pesticides and the specific temperature, salinity, oxygen levels and geophysical parameters of each area under analysis.

By understanding how organisms and ecosystems adapt to environmental changes at a molecular and cellular level, the conclusions drawn from the project will be the basis for studying coastal and ecosystem changes in the coming years.

“We want to answer important questions, like what impacts humans have on the environment. (…) All of our data will be made public, and we hope to be able to start asking much bigger questions and working with very different people to define where to go from here”, says Kiley Seitz.

She adds, “The ultimate goal would be to have bioremediation,” the process of using living organisms to reduce or remove contaminations in the ecosystem, “mediating human impact” on nature.

A goal that “will take years and years”, she acknowledges. “We hope that that foundation is here so that other labs can start to help us by focusing our perspective on how we can do this better.”

The TREC expedition is led by the European Molecular Biology Laboratory (EMBL), the Tara Ocean Foundation, the Tara OceanS Consortium and the European Marine Biological Resources Centre (EMBRC).

In total, the initiative brings together more than 150 research teams from more than 70 institutions in 29 European countries.