Impact of Physical Reef Characteristics on Calcification Rates of the Kāne'ohe Bay Barrier Reef

Abstract

This study elucidates the challenge of quantifying environmental parameters that exert control over calcification by providing an in-situ analysis of how localized variations in reef characteristics impact calcification rates, in addition to comparing calculated calcification rates with those previously published for the barrier reef of Kane‘ohe Bay and mesocosm experiments. NEC and was compared against wind speed (R2=0.08), seawater temperature (R2=0.42), seawater salinity (R2=0.44), and time of sampling within our midday sampling period (R2=0.00). Furthermore, we compared the results of this study with previously published literature on reef-wide calcification rates both for Kane‘ohe Bay and mesocosm experiments. The NEC value determined herein (56.9 ± 32.6 mmol *m-2 *hr-1 ) is comparable to a previous bay-wide estimate (48.3 ± 13.5 mmol *m-2 *hr-1), but larger than found in mesocosm work done with a purely coral community composition (11.2 ± 4.9 mmol *m-2 *hr-1). NEP values exhibited greater variability between this study, a previous bay-wide study, and previous mesocosm work at 210.1 ± 114.6 mmol *m-2 *hr-1, -48.3 ± 16.9 mmol *m-2 *hr-1, and 27.7 ± 4.4 mmol *m-2 *hr-1 respectively. The results of this study highlight the high degree of calcification and production variability seen within Kane‘ohe Bay, the impacts of sub-diel NEC and NEP on the CO2 system in seawater, and illustrate the need for further characterization of parameters affecting NEC and NEP parameters not examined in this study.