Collaborative Research: ULTRA-Data: Synthesizing the role of shallow benthic fluxes in coastal carbon cycle along the East Coast of the United States

Coastal ecosystems provide numerous benefits to people. While much research has focused on the coastal water column, less attention has been given to the importance of the seafloor or sediments of coastal systems. The sediments, however, can recycle nutrients to the water column and support the growth of primary producers such as phytoplankton.

In turn these phytoplankton provide food for nutritionally and commercially important shellfish and finfish. The sediments also store carbon and filter excess nutrients from the water column, thereby improving water quality. This project is focused on bringing together a variety of data sources - from observations to modeling results for the Northeast United States.

This region was chosen because it is relatively data rich compared to other areas and plays an important role in the US blue economy. A literature review and synthesis will be conducted to gather relevant data, and these data will be evaluated to find patterns of variation. Ocean models will then be used to assess changes across this region that could happen on the short and long-term.

Sediment data will also be compared to water column data to see how they are connected, and if their connection is changing over time. This study will engage the scientific community to develop best practice guidelines for sediment data collection and develop community driven priorities for future sediment research studies. The project will provide training for a graduate student and a postdoctoral researcher and support workshops for both scientists and stakeholders.

The seafloor plays a major role in influencing atmospheric carbon dioxide and oxygen concentrations, low-oxygen zones in the ocean, and ocean acidity, and represents the only geologic-scale storage of oceanic carbon. The sediments in coastal areas are particularly important as it is estimated that they account for ~70% of ocean carbon burial. Coastal sediments also recycle nutrients to the water column, fueling future water column primary production, and they can improve water quality via nutrient removal.

Despite their importance, coastal sediments are poorly sampled relative to the water column, with large spatiotemporal gaps in datasets of nutrients and biogenic gas fluxes. The paucity of coastal sediment flux data leads to incomplete estimates for carbon, oxygen, and nutrient budgets in the ocean. Synthesizing disparate datasets of benthic variables therefore addresses an urgent need to improve the understanding of the role of sediments in the carbon and nutrient cycling in coastal regions at multiple timescales.

This effort would further the understanding of mechanisms and environmental conditions influencing benthic dynamics, and consequently the role they play in driving pelagic biogeochemical cycles. The project seeks to do this by focusing on the Northeast US (NE-US), which is a relatively data-rich region. Specifically, existing long-term sediment and water column datasets from the NE-US, model output, and re-analyses will be combined to evaluate the role of different environmental conditions on benthic fluxes of carbon, oxygen, and nutrients.

The project will characterize flux patterns in this region, help interpret the larger context these fluxes were observed in, co-locate different benthic fluxes and related variables in space and time to evaluate their relationship to changing environmental conditions, and develop community driven guidelines for data use and future observations. This project will support an early career scientist, one Ph.D. student, and one postdoctoral researcher.

Results from this study will be disseminated through publications, presentations at scientific conferences, workshops with stakeholders and public outreach events.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.