The ERC AdG-funded NEREIDES expedition, led by Gerhard J. Herndl, returned in August 2025 after investigating the deep waters of the North Atlantic. During this 4-week research cruise aboard the RV Pelagia, the Microbial Oceanography Working Group from the University of Vienna, in collaboration with scientists from Slovenia and the USA, focused on the biogeochemistry and microbial activity of these deep water masses.
A key focus of the expedition was to unravel the role of particles in the carbon flux from the sunlit surface waters to depths below 3,000 meters. Additionally, the team explored how hydrostatic pressure influences microbial activity in these extreme environments.
Back in the lab, detailed analyses using metagenomics and metaproteomics will help determine the composition and function of microbial communities across different water masses. The ultimate goal of the project is to gain a more refined understanding of the various types of particle rain in the ocean’s interior and their role in carbon cycling.
All in all, the cruise was a resounding success!
For more details, check out the Rudolphina article by Maria Teixeira Pinto.