Ocean Acidification in an Intensely Farmed Coastal Bay System

· 02/2023 - 01/2024

Project number: 2023-R/RRHC-008
Strategic Focus Area: Healthy Coastal Ecosystems

Lead PI: Ralston David, Woods Hole Oceanographic Institution

To characterize spatial and temporal variability in water quality parameters in Duxbury Bay, to assess the relative influences of the factors contributing to acidification in the estuary, and to convey useful results to stakeholders including local oyster farmers, educators, and environmental managers.

We will conduct shipboard surveys measuring water quality parameters in Duxbury Bay repeated monthly from April through October. We will deploy moored instruments along the estuarine salinity gradient to record time series of water quality parameters and tidal currents. We will develop a circulation model to help interpret the observations and assess the role of tidal exchange. Analyses will synthesize the various data sources to characterize spatial and temporal variability in salinity, temperature, pH, and dissolved oxygen. We will work with the Duxbury Bay Maritime School and local oyster growers to develop data products relevant to their needs.

Ocean acidification (OA) is a growing concern globally due to increasing atmospheric carbon dioxide, and it is exacerbated in many coastal embayments due to eutrophication and depends on local freshwater inputs. Aquaculture is particularly threatened by OA due to its adverse effects on shellfish development, and growers have already begun to adjust their operations to mitigate impacts. A better understanding of the spatial and temporal variability in water quality would help inform mitigation strategies. Duxbury Bay, with it extensive development and a thriving aquaculture industry, is an ideal study site to examine these issues.