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Abstract Microbial ecological functions are an emergent property of community composition. For some ecological functions, this link is strong enough that community composition can be used to estimate the quantity of an ecological function. Here, we apply random forest regression models to compare the predictive performance of community composition and environmental data for bacterial production (BP). Using data from two independent long-term ecological research sites—Palmer LTER in Antarctica and Station SPOT in California—we found that community composition was a strong predictor of BP. The top performing model achieved an R2 of 0.84 and RMSE of 20.2 pmol L−1 hr−1 on independent validation data, outperforming a model based solely on environmental data (R2 = 0.32, RMSE = 51.4 pmol L−1 hr−1). We then operationalized our top performing model, estimating BP for 346 Antarctic samples from 2015 to 2020 for which only community composition data were available. Our predictions resolved spatial trends in BP with significance in the Antarctic (P value = 1 × 10−4) and highlighted important taxa for BP across ocean basins. Our results demonstrate a strong link between microbial community composition and microbial ecosystem function and begin to leverage long-term datasets to construct models of BP based on microbial community composition. 

From our climate to the air we breathe, the ocean influences the world around us. Scientists are always looking for new ways to explore and study the ocean. One way we do this is by going on specially designed ships that allow us to study the deep sea, far from land. On our latest expedition aboard the Research Vessel Sally Ride, we went out 300 miles into the North Pacific Ocean for a week. We used some of the most important ocean science tools to catch tiny marine animals, collect water from some of the deepest depths, uncover mysteries of oceans past, and study how desert dust feeds marine animals today. 

The Antarctic marine environment is a dynamic ecosystem where microorganisms play an important role in key biogeochemical cycles. Despite the role that microbes play in this ecosystem, little is known about the genetic and metabolic diversity of Antarctic marine microbes. In this study we leveraged DNA samples collected by the Palmer Long Term Ecological Research (LTER) project to sequence shotgun metagenomes of 48 key samples collected across the marine ecosystem of the western Antarctic Peninsula (wAP). We developed an in silico metagenomics pipeline (iMAGine) for processing metagenomic data and constructing metagenome-assembled genomes (MAGs), identifying a diverse genomic repertoire related to the carbon, sulfur, and nitrogen cycles. A novel analytical approach based on gene coverage was used to understand the differences in microbial community functions across depth and region. Our results showed that microbial community functions were partitioned based on depth. Bacterial members harbored diverse genes for carbohydrate transformation, indicating the availability of processes to convert complex carbons into simpler bioavailable forms. We generated 137 dereplicated MAGs giving us a new perspective on the role of prokaryotes in the coastal wAP. In particular, the presence of mixotrophic prokaryotes capable of autotrophic and heterotrophic lifestyles indicated a metabolically flexible community, which we hypothesize enables survival under rapidly changing conditions. Overall, the study identified key microbial community functions and created a valuable sequence library collection for future Antarctic genomics research. 

Understanding the history of how we studied our ocean in the past and how we study it now will help us develop approaches to make future oceanographic knowledge production more diverse, accessible, and inclusive. The motto of the UN Decade of Ocean Science for Sustainable Development (2021–2030) is, “The ocean we need for the future we want” (Singh et al., 2021). The Ocean Decade gives the ocean sciences community an opportunity to change the way it conducts research, to use ocean science to support sustainable development, and to energize the ocean sciences for future generations. With these goals in mind, we developed an introductory level, student-led graduate seminar that builds on the Ocean Decade framework. A research cruise involving seminar participants followed the seminar sessions. Here, we discuss how we conducted the seminar and highlight directions that are needed to energize future generations of ocean leaders and make ocean science more equitable, inclusive, and accessible.