Very little is known about how microbial community composition and function relate to biological oceanographic processes. This is largely due to the difficulty of integrating molecular biological-based community composition measurements into an oceanographic measurement program, even though recent data imply that microbial diversity should strongly affect many biogeochemical processes. New developments in whole-community molecular fingerprinting approaches and high throughput sequence analysis make such integration possible. In this project, the PIs will evaluate microbial community diversity in the context of environmental data, as a critical first step toward relating molecular genetic data to processes that may be represented in conceptual and numerical models of the ocean. The project is very cost effective because no additional fieldwork is requested. Instead, the PIs will use existing high quality biological oceanographic data from predominantly subtropical or tropical regions. Samples come from the SW Pacific around Australia, the North Pacific from Hawaii to Empress Seamount, the W Tropical Atlantic including the Amazon Plume, the Gulf of Mexico on the West Florida Shelf, and the San Pedro Ocean Time Series between Los Angeles and Santa Catalina Island. Molecular and oceanographic data will be analyzed by multivariate statistical techniques including ordination, cluster, and canonical analysis. Questions to be addressed include: Do physico-chemical parameters structure microbial communities? Do some microbial taxa appear together regularly, and are some taxa mutually exclusive? Can correlations be used to connect certain taxa to specific biogeochemical processes? The project includes a significant exploratory component, and is expected to generate numerous specific hypotheses to test. The results will be digitally archived and can be integrated with new data on marine microbial diversity as it becomes available. Broader impacts of the project include a connection to K-12 teaching through USC's COSEE West program, undergraduate and graduate student teaching and research, and outreach to the general public through a website.
