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USGS · 70102289

Air-water gas exchange and CO2 flux in a mangrove-dominated estuary

David T. Ho·Sara Ferrón·Victor C. Engel·Laurel G. Larsen·Jordan G. Barr
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Abstract

Mangrove forests are highly productive ecosystems, but the fate of mangrove-derived carbon remains uncertain. Part of that uncertainty stems from the fact that gas transfer velocities in mangrove-surrounded waters are not well determined, leading to uncertainty in air-water CO 2 fluxes. Two SF 6 tracer release experiments were conducted to determine gas transfer velocities (k(600) = 8.3 ± 0.4 and 8.1 ± 0.6 cm h −1 ), along with simultaneous measurements of pCO 2 to determine the air-water CO 2 fluxes from Shark River, Florida (232.11 ± 23.69 and 171.13 ± 20.28 mmol C m −2 d −1 ), an estuary within the largest contiguous mangrove forest in North America. The gas transfer velocity results are consistent with turbulent kinetic energy dissipation measurements, indicating a higher rate of turbulence and gas exchange than predicted by commonly used wind speed/gas exchange parameterizations. The results have important implications for carbon fluxes in mangrove ecosystems.

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Geophysical Research LettersArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 24.85° to 25.998° latitude; -81.6256° to -80.2514° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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David T. Ho, Sara Ferrón, Victor C. Engel, Laurel G. Larsen, Jordan G. Barr. 2014-01-09. Air-water gas exchange and CO2 flux in a mangrove-dominated estuary. https://doi.org/10.1002/2013gl058785

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