Over the course of the NITRODEOX project, significant progress was made in understanding how ocean deoxygenation affects microbial communities and nitrogen cycling. A central achievement was the successful execution of a 35-day oceanographic campaign in the Eastern Tropical South Pacific (ETSP), aboard the R/V Roger Revelle. This expedition, conducted during a strong El Niño event, provided a unique opportunity to study microbial and biogeochemical dynamics across a gradient of oxygen concentrations, including the core and boundary of the oxygen minimum zone (OMZ).
During the cruise, the fellow and lab colleagues collected approximately 4,000 samples across multiple depths and stations. These samples were used to quantify N2O concentration, and nitrogen transformation rates—particularly nitrification, denitrification, and N2O production. The samples produced during these experiments have been already measured. The fellow is currently working on analyzing these results. In parallel, hundreds of samples were processed for DNA and RNA extraction, forming the basis for ongoing metagenomic analyses. These analyses aim to characterize microbial taxonomic and functional diversity and to build microbial association networks linked to nitrogen cycling. These analyses are still ongoing.
Training has been a cornerstone of the project. The fellow received hands-on experience in oceanography, bioinformatics, and network inference analysis, supported by expert mentorship and institutional resources. She participated in specialized workshops and seminars, enhancing her skills in metagenomics, data visualization, and scientific communication.
Dissemination activities have included presentations at international conferences (ASLO, ISME), invited talks at leading institutions (WHOI), and outreach events targeting diverse audiences. Two scientific manuscripts are in preparation, based on the ETSP campaign and complementary datasets.
