Assessing ecosystem responses of Gulf of Mexico coastal communities to ocean acidification using environmental DNA
Why we care
Recent efforts to monitor ocean acidification in the Gulf of Mexico via the Gulf of Mexico Ecosystems and Carbon Cycle (GOMECC) cruises have revealed spatial differences in ocean acidification. While we know that ocean acidification negatively impacts many species and exacerbates the effects of oxygen limitation and harmful algal blooms, there is little work to monitor or predict the effects of ocean acidification on biodiversity. This project employs cutting-edge technology using environmental DNA to assess biodiversity in different conditions in the Gulf of Mexico region.
What we are doing
Every organism sheds DNA. This project analyzes environmental DNA (eDNA), which is free-floating or microscopic DNA found in seawater, collected during the 4th GOMECC cruise, to identify biodiversity of bacteria, plankton, and fish in the Gulf of Mexico. eDNA will be compared to ocean properties to draw conclusions about drivers of biodiversity.
Benefits of our work
Links between eDNA, ocean acidification, and other ocean properties will provide a deeper understanding of environmental drivers of biodiversity. These relationships can inform predictions of biodiversity patterns and guide the management of key habitats in the Gulf of Mexico, and help us adapt to changing ocean conditions.
Among the NOAA designated Large Marine Ecosystems, the Gulf
of Mexico (GOM) remains poorly understood in terms of its current OA conditions, despite its
ecological and economic significance. In the northwestern GOM (nwGOM), decadal
acidification has been observed in the shelf-slope region, with metabolic production of CO2
contributing to a larger fraction of CO2 accumulation than uptake of anthropogenic CO2, and the
observed rate of acidification is significantly greater than that in other tropical and subtropical
areas. Unfortunately, whether the observed OA in this region represents a short-term
phenomenon or a long-term trend is unknown.
It is hypothesized that increasing atmospheric CO2, increasing terrestrial nutrient export
due to an enhanced hydrological cycle, and enhanced upwelling due to climate change will cause
the continental shelf-slope region in the nwGOM to acidify faster than other tropical and
subtropical seas. In order to test this hypothesis wave gliders, in -stiu sensor along withe underway measurements from research vessels will measure carbonated chemistry in in surface and shallow waters. Modeling will be used tp integrate the chemical signals into the models to hindcast/predict spatia; and temporal variation of the OA signal for the the optimization of monitoring design and implementation.