Atmospheric CO₂ fluxes in a highly polluted estuary (the Scheldt)

Dissolved CO 2 concentration and exchange with the atmosphere were investigated simultaneously in the Scheldt estuary. CO 2 partial pressures as high as 5,700 µ atm, corresponding to oversaturation with respect to the atmosphere of 1,600%, were observed in the upper estuary. The corresponding atmospheric CO 2 fluxes reached values of up to 1.2 mol m −2 d −1 . The estimated flux for the entire estuary amounts to 600 t of C d −1 for a river discharge of <1×10 6 m 3 d −1 .