A comparative study of carbon dioxide degassing in river- and marine-dominated estuaries

作者：Jiang Li Qing; Cai Wei Jun^*; Wang Yongchen

来源：Limnology and Oceanography, 2008, 53(6): 2603-2615.

DOI：10.4319/lo.2008.53.6.2603

• Carbon Dioxide
• Dissolved Inorganic Carbon
• Estuaries
• Gas-exchange Rates
• Transfer Velocities
• Fluxes
• Water
• Marsh
• River-dominated
• Marine-dominated

The partial pressure of carbon dioxide (pCO(2)), concentration of total dissolved inorganic carbon, and total alkalinity were measured at both high tide and low tide in the surface water of three Georgia estuaries from September 2002 to May 2004. Of the three estuaries, Sapelo and Doboy Sounds are marine-dominated estuaries, while Altamaha Sound is a river-dominated estuary. During all sampling months, the three estuaries were supersaturated in CO(2) with respect to the atmosphere (39.5-342.5 Pa, or 390-3380 matm) because of CO(2) inputs from within the estuarine zone (mainly intertidal marshes) and the river. Overall, pCO(2) in the river-dominated estuary is much higher than that in the marine-dominated estuaries. The calculated annual air-water CO(2) flux in Altamaha Sound (69.3 mmol m(-2) d(-1)) is 2.4 times those of Sapelo and Doboy Sounds (28.7-29.4 mmol m(-2) d(-1)). The higher CO(2) degassing in the river-dominated estuary is fueled largely by CO(2) loading from the river. Because of the substantial differences between river- and marine-dominated estuaries, current estimates of air-water CO(2) fluxes in global estuaries (which are based almost entirely on river-dominated estuaries) could be overestimated.

• 出版日期2008-11