Suitability of the shallow water hydrothermal system at Ambitle Island (Papua New Guinea) to study the effect of high pCO2 on coral reefs

A unique temperate rocky coastal hydrothermal vent system (Whakaari–White Island, Bay of Plenty, New Zealand): constraints for ocean acidification studies

“…Even though shallow submarine CO 2 vents are not exact analogues of future ocean conditions, they are commonly used as the best natural settings to investigate community composition shifts and ecosystem-scale effects of OA, over long timescales (Hall-Spencer et al 2008;Fabricius et al 2011;Pichler et al 2019). The suitability of the unique rocky coastal temperate submarine CO 2 vents around Whakaari-White Island in the Bay of Plenty (New Zealand) as a 'living laboratory' for OA science is discussed below.…”

“…The main limitations in using shallow marine hydrothermal systems as natural analogues of future conditions are: the large temporal variabilities in pH with periods of time where pH values reach ambient levels or undersaturated conditions (e.g. Boatta et al 2013;Fabricius et al 2014;Dahms et al 2018;González-Delgado and Hernández 2018;Pichler et al 2019) the limited area affected by vent emissions and resulting area with low pH and potentially higher temperatures (Boatta et al 2013;Pichler et al 2019) the continuous supply of larvae and propagules from outside the vent system (e.g. Levin et al 2016;Boyd et al 2018;Hawkins et al 2018), which hampers the ability to use these sites to determine whether dispersive populations could adapt to environmental stressors over multiple generations the eventuality that some organisms that live at CO 2 vents could have higher tolerance thresholds for environmental stressors owing to the possibility of evolving and genetically adapting over long timescales to extreme physicochemical conditions (e.g.…”

“…the potential presence at toxic concentrations of elements and gases), which may have confounding effects on vent biota (e.g. Cunha et al 2008;Chen et al 2018;Dahms et al 2018;González-Delgado and Hernández 2018;Hawkins et al 2018;Pichler et al 2019).…”

“…Thus, it is surprising that so far most shallow vent studies of biological nature limited their element measurements to gases (e.g. CO 2 , H 2 S, CH 4 , N 2 , O 2 ; Pichler et al 2019) and sediments (e.g. Vizzini et al 2013), despite elements in solution being potentially key factors for the assessment of the suitability of vent systems for the study of climate change effects on marine biota (Vizzini et al 2013).…”

“…Rossi and Tunnicliffe 2017) or in tropical to subtropical coral reef environments in Papua New Guinea (e.g. Fabricius et al 2011;Morrow et al 2015;Takahashi et al 2016;Pichler et al 2019), Japan (Inoue et al 2013;Agostini et al 2015), Canary Islands (Hernández et al 2016) and Mariana Islands (Enochs et al 2015). OA studies of shallow vents in cooler waters of the Southern Hemisphere are still scarce.…”