Fig. 4
From: Redox reactions and weak buffering capacity lead to acidification in the Chesapeake Bay
Model simulations of the evolution of total alkalinity, dissolved inorganic carbon, pH, and O2 during biogeochemical processes. a Total alkalinity (TA) and dissolved inorganic carbon (DIC) relationship and b pH (25 °C and NBS scale) and [O2] relationship. The biogeochemical pathway, or TA and DIC loci, includes aerobic respiration (AR), sulfate reduction (SR) and CaCO3 dissolution (CD). Predicted pH or TA values are provided together with observed pH or TA (calculated from pH and DIC data from August 2013). Both sequential (open circles) and simultaneous (triangles) pathways are presented. Purple arrows represent acidification generated by oxidation of reduced chemicals (H2S). The light shaded line at the top indicates the pH and [O2] relationship from the Gulf of Mexico reflecting aerobic respiration
