Acidification at the oxic-anoxic boundary in Chesapeake Bay waters

It is known that eutrophication and its subsequent respiration can lead to bottom-water acidification in coastal oceans in addition to the anthropogenic CO₂ uptake-induced OA. It is however not known how the production and consumption of reduced chemicals would do to the acidification in very low oxygen or anoxic environments. We report here an extreme acidification caused by the oxidation of reduced chemicals (H₂S and NH₃) in waters with an already weakening buffer capacity in the Chesapeake Bay. A simple model quantitatively links the acidification to redox reactions at the oxic-anoxic boundary and suggests this could be a common phenomenon in many coastal water bodies.