Amelioration of ocean acidification and warming effects through physiological buffering of a macroalgae

Concurrent anthropogenic global climate change and ocean acidification is expected to have a negative impact on calcifying marine organisms. While knowledge of biological responses of organisms to oceanic stress has emerged from single species experiments, these do not capture ecologically relevant scenarios where the potential for multi-organism physiological interactions is assessed. Marine algae provide an interesting case study, as their photosynthetic activity elevates pH in the surrounding microenvironment, potentially buffering more acidic conditions for associated epiphytes. We present findings that indicate increased tolerance of an important epiphytic foraminifera, Marginopora vertebralis, to the effects of increased temperature (±3 °C) and pCO2 (~1000 µatm) when associated with its common algal host, Laurencia intricata. Specimens of M. vertebralis were incubated for 15 days in flow-through aquaria simulating current and end-of-century temperature and pH conditions. Physiolog...