Premium
Inorganic carbon speciation and fluxes in the Congo River
Author(s) -
Wang Zhaohui Aleck,
Bienvenu Dinga Jean,
Mann Paul J.,
Hoering Katherine A.,
Poulsen John R.,
Spencer Robert G. M.,
Holmes Robert M.
Publication year - 2013
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/grl.50160
Subject(s) - alkalinity , dissolved organic carbon , total inorganic carbon , carbonate , bicarbonate , environmental chemistry , titration , carbon fibers , total organic carbon , carbonic acid , genetic algorithm , surface water , chemistry , environmental science , carbon dioxide , inorganic chemistry , environmental engineering , ecology , biology , materials science , organic chemistry , composite number , composite material
Seasonal variations in inorganic carbon chemistry and associated fluxes from the Congo River were investigated at Brazzaville‐Kinshasa. Small seasonal variation in dissolved inorganic carbon (DIC) was found in contrast with discharge‐correlated changes in pH, total alkalinity (TA), carbonate species, and dissolved organic carbon (DOC). DIC was almost always greater than TA due to the importance of CO 2 *, the sum of dissolved CO 2 and carbonic acid, as a result of low pH. Organic acids in DOC contributed 11–61% of TA and had a strong titration effect on water pH and carbonate speciation. The CO 2 * and bicarbonate fluxes accounted for ~57% and 43% of the DIC flux, respectively. Congo River surface water released CO 2 at a rate of ~109 mol m −2 yr −1 . The basin‐wide DIC yield was ~8.84 × 10 4 mol km −2 yr −1 . The discharge normalized DIC flux to the ocean amounted to 3.11 × 10 11 mol yr −1 . The DOC titration effect on the inorganic carbon system may also be important on a global scale for regulating carbon fluxes in rivers.