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

Dissolved CO2 concentration and exchange with the atmosphere were investigated simultaneously in the Scheldt estuary. CO2 partial pressures as high as 5,700 µatm, corresponding to oversaturation with respect to the atmosphere of 1,600%, were observed in the upper estuary. The corresponding atmospheric CO2 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 <1×106 m3 d−1.