TREC and Tara EUROPA - planetary biology along the European coastline

Between March 2023 and September 2024, the Tara Europa expedition embarked 50 international scientists to systematically deploy over 60 protocols at 188 sites along the European coastline from Finland to Greece. Covering the waters of 19 countries, the teams on board Tara measured a suite of oceanographic (bio)physical parameters and recovered approximately 23,000 samples to characterize the mosaic of coastal aquatic ecosystems along the way, ranging from molecules to organisms and from viruses to animals. Tara Europa was the ocean part of a larger initiative, TREC - Traversing European Coastlines -, led by the European Molecular Biology Laboratory (EMBL), which aims to explore life across the basic components of the Earth system: soils, sediments, waters, and air. While Tara focused on sampling marine waters and aerosols, a fleet of EMBL mobile laboratories collected data from shallow waters, sediments, soils, and air. Overall, TREC involved 90 institutions across 30 countries, systematically collecting over 70,000 samples from 115 land-to-sea gradients. The sampling strategy was designed to encompass various habitats and geomorphologies (open coasts or estuaries), including areas impacted by human activity (agriculture, urbanization), as well as pristine environments and sharp climate gradients—ranging from brackish waters in the Baltic Sea to hyper-saline warm waters in the Mediterranean.  In addition to a comprehensive suite of cutting-edge meta-omics techniques (metagenomics, metatranscriptomics, metabarcoding, metametabolomics, metaproteomics, metamorphomics), we measured key contextual (bio)physical and biogeochemical parameters, including trace metals and over 4,000 pollutants (pesticides, drugs, etc.). We also deployed state-of-the-arts imaging tools and novel phenogenomics protocols in the EMBL Advanced Mobile Laboratory, for systematic and much deeper understanding of interactions, functions, and processes at cellular and subcellular levels. All together, this expedition represents the largest consistent exploration of life across the dimensions and drivers of the Earth systems, including local and global anthropogenic impacts. Beyond uncovering a wealth of novel molecules, genes, and species, TREC will illuminate fundamental molecular and cellular mechanisms underlying the interactions occurring between taxa and ecosystems, from which emerge ecosystems and planetary functions and their adaptation and evolution. TREC also lays the groundwork for distributed yet integrative planetary biology research through foundational concepts, infrastructure, methods, and baseline datasets.