Carbon cycling and oxygen dynamics at the seafloor

The seafloor plays a critical role in global carbon cycling, and thus is important to global climate change studies, including those on warming trends and ocean acidification. On smaller size scales, carbon cycling assessments are used to evaluate aquatic ecosystem health and trophic status. The oxygen flux between the seafloor and the water above integrates major benthic carbon transformations processes and is widely used as a proxy for benthic primary production and organic matter mineralization. In this talk, I review traditional methods for benthic oxygen flux measurements and explain the principles of aquatic eddy covariance, a relatively new approach for measuring benthic oxygen fluxes under naturally varying in situ conditions. I then give examples of the new insights that can be attained with the aquatic eddy covariance technique. These examples focus on benthic substrates where traditional flux methods are difficult or impossible to use. Lastly, I highlight new developments in the approach and give my view of future applications of the aquatic eddy covariance technique.