Award: OCE-1848576

The aim of this project was to combine genomics and new mathematical approaches to understand the role of plankton biodiversity in ocean carbon and nutrient cycles. The project resulted in several transformative discoveries. Marine microorganisms rapidly adapt to changes in the environment. We sequenced the microbiomes from many regions and used such adaptive genomic mutations as a biosensor for ocean environmental changes. This approach provided the first global description of phytoplankton nutrient limitation. We next integrated these ‘omics field observations with measurements of ecosystem carbon and nutrient stocks. Traditionally, the elemental composition of marine communities has been considered static at Redfield proportions. However, our project clearly demonstrated regional variation in the carbon:nitrogen:phosphorus ratios linked to plankton nutrient limitation. Finally, we integrated ‘omics and biogeochemical measurements with a new generation of Earth system models to quantify how plankton physiology and adaptation regulation ocean biogeochemical cycles. This resulted in a new understanding of both marine nitrogen fixation and carbon sequestration. Thus, we demonstrated how adaptative resource in marine ecosystems can have large implications for marine biodiversity, biogeochemical functioning, and atmospheric levels. As such, future variations in ocean community C:N:P may represent one of the most important biological feedbacks to climate change. The project several broader impacts. First, we demonstrated the importance of convergent science approach for understanding the importance of biological responses for the global carbon and nutrient cycles. The project showed how to integrate molecular processes controlling microbial resource allocations with a global Earth System model. Second, we trained a large undergraduate and graduate student cohort in convergent science approaches. Students also had the opportunity to learn diverse skills across disciplines. As a result, many of the most impactful studies were student-led. Last Modified: 12/05/2022 Submitted by: Adam C Martiny