TY - JOUR
T1 - Effects of diurnally oscillating pCO(2) on the calcification and survival of coral recruits
AU - Dufault, Aaron M.
AU - Cumbo, Vivian R.
AU - Fan, Tung Yung
AU - Edmunds, Peter J.
PY - 2012/8/7
Y1 - 2012/8/7
N2 - Manipulative studies have demonstrated that ocean acidification (OA) is a threat to coral reefs, yet no experiments have employed diurnal variations in pCO2 that are ecologically relevant to many shallow reefs. Two experiments were conducted to test the response of coral recruits (less than 6 days old) to diurnally oscillating pCO2; one exposing recruits for 3 days to ambient (440 μatm), high (663 μatm) and diurnally oscillating pCO2 on a natural phase (420-596 μatm), and another exposing recruits for 6 days to ambient (456 μatm), high (837 μatm) and diurnally oscillating pCO2 on either a natural or a reverse phase (448-845 μatm). In experiment I, recruits exposed to natural-phased diurnally oscillating pCO2 grew 6-19% larger than those in ambient or high pCO2. In experiment II, recruits in both high and natural-phased diurnally oscillating pCO2 grew 16 per cent larger than those at ambient pCO2, and this was accompanied by 13-18% higher survivorship; the stimulatory effect on growth of oscillatory pCO2 was diminished by administering high pCO2 during the day (i.e. reverse-phased). These results demonstrate that coral recruits can benefit from ecologically relevant fluctuations in pCO2 and we hypothesize that the mechanism underlying this response is highly pCO2-mediated, night-time storage of dissolved inorganic carbon that fuels daytime calcification.
AB - Manipulative studies have demonstrated that ocean acidification (OA) is a threat to coral reefs, yet no experiments have employed diurnal variations in pCO2 that are ecologically relevant to many shallow reefs. Two experiments were conducted to test the response of coral recruits (less than 6 days old) to diurnally oscillating pCO2; one exposing recruits for 3 days to ambient (440 μatm), high (663 μatm) and diurnally oscillating pCO2 on a natural phase (420-596 μatm), and another exposing recruits for 6 days to ambient (456 μatm), high (837 μatm) and diurnally oscillating pCO2 on either a natural or a reverse phase (448-845 μatm). In experiment I, recruits exposed to natural-phased diurnally oscillating pCO2 grew 6-19% larger than those in ambient or high pCO2. In experiment II, recruits in both high and natural-phased diurnally oscillating pCO2 grew 16 per cent larger than those at ambient pCO2, and this was accompanied by 13-18% higher survivorship; the stimulatory effect on growth of oscillatory pCO2 was diminished by administering high pCO2 during the day (i.e. reverse-phased). These results demonstrate that coral recruits can benefit from ecologically relevant fluctuations in pCO2 and we hypothesize that the mechanism underlying this response is highly pCO2-mediated, night-time storage of dissolved inorganic carbon that fuels daytime calcification.
UR - http://www.scopus.com/inward/record.url?scp=84863111070&partnerID=8YFLogxK
U2 - 10.1098/rspb.2011.2545
DO - 10.1098/rspb.2011.2545
M3 - Article
C2 - 22513858
AN - SCOPUS:84863111070
SN - 0962-8452
VL - 279
SP - 2951
EP - 2958
JO - Proceedings of the Royal Society B: Biological Sciences
JF - Proceedings of the Royal Society B: Biological Sciences
IS - 1740
ER -