TY - JOUR
T1 - Growth form-dependent response to physical disturbance and thermal stress in Acropora corals
AU - Muko, S.
AU - Arakaki, S.
AU - Nagao, M.
AU - Sakai, Kazuhiko
N1 - Funding Information:
Acknowledgments This work was supported by JST PRESTO program to S.M., partly by the twenty-first century COE program of the University of the Ryukyus, JSPS KAKENHI (Nos. 21247006 and 21570021), and Iriomote Project of the Research Institute for Humanity and Nature to S. K. The field measurements of the water temperatures were conducted as a part of the project named ‘‘Interactions between natural environment and human social systems in subtropical Island,’’ promoted by Research Institute for Humanity and Nature (RIHN). We thank N. Yamaguchi and N. Kumagai for their statistical advice.
PY - 2013/3
Y1 - 2013/3
N2 - To predict the community structure in response to changing environmental conditions, it is necessary to know the species-specific reaction and relative impact strength of each disturbance. We investigated the coral communities in two sites, an exposed and a protected site, at Iriomote Island, Japan, from 2005 to 2008. During the study period, a cyclone and thermal stress were observed. All Acropora colonies, classified into four morphologies (arborescent, tabular, corymbose, and digitate), were identified and tracked through time to calculate the annual mortality and growth rate. The mortality of all Acropora colonies in the protected site was lower than that in the exposed site during the period without disturbances. Extremely higher mortality due to bleaching was observed in tabular and corymbose Acropora, compared to other growth forms, at the protected sites after thermal stress. In contrast, physical disturbance by a tropical cyclone induced the highest mortality in arborescent and digitate corals at the exposed site. Moreover, arborescent corals exhibited a remarkable decline 1 year after the tropical cyclone at the exposed site. The growth of colonies that survived coral bleaching did not decrease in the following year compared to previous year for all growth forms, but the growth of arborescent and tabular remnant corals at the exposed site declined severely after the tropical cyclone compared to previous year. The delayed mortality and lowered growth rate after the tropical cyclone were probably due to the damage caused by the tropical cyclone. These results indicate that the cyclone had a greater impact on fragile corals than expected. This study provides useful information for the evaluation of Acropora coral response to progressing global warming conditions, which are predicted to increase in frequency and intensity in the near future.
AB - To predict the community structure in response to changing environmental conditions, it is necessary to know the species-specific reaction and relative impact strength of each disturbance. We investigated the coral communities in two sites, an exposed and a protected site, at Iriomote Island, Japan, from 2005 to 2008. During the study period, a cyclone and thermal stress were observed. All Acropora colonies, classified into four morphologies (arborescent, tabular, corymbose, and digitate), were identified and tracked through time to calculate the annual mortality and growth rate. The mortality of all Acropora colonies in the protected site was lower than that in the exposed site during the period without disturbances. Extremely higher mortality due to bleaching was observed in tabular and corymbose Acropora, compared to other growth forms, at the protected sites after thermal stress. In contrast, physical disturbance by a tropical cyclone induced the highest mortality in arborescent and digitate corals at the exposed site. Moreover, arborescent corals exhibited a remarkable decline 1 year after the tropical cyclone at the exposed site. The growth of colonies that survived coral bleaching did not decrease in the following year compared to previous year for all growth forms, but the growth of arborescent and tabular remnant corals at the exposed site declined severely after the tropical cyclone compared to previous year. The delayed mortality and lowered growth rate after the tropical cyclone were probably due to the damage caused by the tropical cyclone. These results indicate that the cyclone had a greater impact on fragile corals than expected. This study provides useful information for the evaluation of Acropora coral response to progressing global warming conditions, which are predicted to increase in frequency and intensity in the near future.
UR - http://www.scopus.com/inward/record.url?scp=84874789914&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84874789914&partnerID=8YFLogxK
U2 - 10.1007/s00338-012-0967-z
DO - 10.1007/s00338-012-0967-z
M3 - Article
AN - SCOPUS:84874789914
VL - 32
SP - 269
EP - 280
JO - Coral Reefs
JF - Coral Reefs
SN - 0722-4028
IS - 1
ER -