The Physiological Response of Two Green Calcifying Algae from the Great Barrier Reef towards High Dissolved Inorganic and Organic Carbon (DIC and DOC) Availability

摘要: Increasing dissolved inorganic carbon (DIC) concentrations associated with ocean acidification can affect marine calcifiers, but local factors, such as high organic (DOC) through sewage and algal blooms, may interact this global factor. For calcifying green algae of the genus Halimeda, a key tropical carbonate producer that often occurs in coral reefs, no studies on these interactions have been reported. These data are however urgently needed to understand future production. Thus, we investigated independent combined effects DIC (pCO2 402 μatm/ pHtot 8.0 996 7.7) DOC (added glucose 0 294 μmol L-1) growth, calcification photosynthesis H. macroloba opuntia from Great Barrier Reef an incubation experiment over 16 days. High significantly reduced dark by 130 % led net dissolution, did not macroloba. daily oxygen production 78 43 %, respectively, 70%. Combined show any interactive for both algae, revealed additive where combination factors 162 compared controls. Such species-specific differences treatment responses indicate is more susceptible than From ecological perspective, results further suggest reduction primary Halimeda-dominated benthic reef communities under additional decreases accretion elevated concentrations, dominates community. This reduce biogenic sedimentation rates hence buffering capacity against acidification.