Carbon dioxide dynamics in streams entering Kaneohe Bay, Hawaiʻi

Abstract

The open ocean is now largely a sink of atmospheric carbon dioxide (CO2), promoting ocean acidification. Because the CO2 dynamics of coastal regions are complex, it remains unclear whether such areas act as a net sink or source of CO2. For this study, Kaneohe, Ahuimanu, and Waiahole Streams were compared with the Coral Reef Instrumented Measurement and CO2 Monitoring Platform-2 (CRIMP-2) buoy during baseline and storm conditions. The compiled results provide data including total alkalinity, dissolved inorganic carbon, nutrients, pCO2, and CO2 fluxes. Conclusions addressed the potential effects from land use change in the watershed and the effects of groundwater on stream carbon system. This work examined connections between the streams and Kaneohe Bay and their roles as net sources or sinks of CO2 to the atmosphere during baseline and storm conditions. The concepts explored as well as the results can be applied to other tropical and subtropical high islands.