Submarine Groundwater Discharge Releases CO2 to a Coral Reef
Document Type
Article
Publication Date
8-4-2021
Abstract
Submarine groundwater discharge (SGD) flows into coral reefs. In volcanically active areas; the incoming groundwater is typically CO2-rich which can alter the carbon balance and views on how coral reefs function at prevailing high CO2. We quantified dynamic hydrothermal SGD and CO2 fluxes to a Philippine coral reef over a spring-neap tidal cycle. SGD rates; with mean of 35 cm d−1 and 5−95% range of 0−147.8 cm d−1 . The groundwater-CO2 fluxes (266 mmol m d−1; range: 0−1111 mmol m2 d−1) were up to ∼300-fold larger than evasion of CO2 to the atmosphere. The reef seawater pCO2 (493 μatm; range: 421−680 μatm) remained above atmospheric values and spanned the upper end of the range of atmospheric levels (400−500 μatm) expected for the next century. Because of the hydrothermal SGD; the reef has prevailing above-atmospheric CO2 and is a source to the atmosphere and nearby waters.
Recommended Citation
Correa, R. E., Cardenas, M. B., Rodolfo, R. S., Lapus, M. R., Davis, K. L., Giles, A. B., Fullon, J. C., Hajati, M.-C., Moosdorf, N., Sanders, C. J., & Santos, I. R. (2021). Submarine groundwater discharge releases CO2 to a coral reef. ACS ES&T Water, 1(8), 1756–1764. https://doi.org/10.1021/acsestwater.1c00104
