Variations in massive Porites growth rates at Hainan Island, northern South China Sea

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 546:47-60 (2016) - DOI: https://doi.org/10.3354/meps11654 Variations in massive Porites growth rates at Hainan Island, northern South China Sea Ruixia Su1, J. M. Lough2,3,*, Donghuai Sun4 1Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, PR China 2Australian Institute of Marine Science, PMB 3, Townsville MC, Queensland 4810, Australia 3ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia 4Key Laboratory of West China’s Environment System, Lanzhou University, Lanzhou 730000, PR China *Corresponding author: j.lough@aims.gov.au ABSTRACT: Annual density banding in massive coral skeletons provides a means to retrospectively monitor coral growth rates. In this study, we present new records of annual skeletal density, linear extension and calcification rates for 16 Porites spp. coral cores from northeastern Hainan Island, northern South China Sea. Based on average growth characteristics from 1948 to 2001, P. lobata had significantly higher linear extension and calcification rates and lower density than P. lutea. We also found evidence of an age-related effect on growth, whereby skeletal density decreased and linear extension rate increased through time. This did not affect calcification rates. The average calcification rate for northeastern Hainan Island Porites matches that expected for Indo-Pacific Porites based on average sea surface temperatures (SST) from 1961 to 1990. After removal of the ontogenetic trends, average 16-core calcification rates from 1923 to 2002 showed an initial increase, matching observed SST warming. After 1982, however, calcification significantly decreased, although SST did not continue to warm. We suggest that the lower calcification rates from 1983 to 2002 may be a response to eutrophication of coastal waters as a result of extensive coastal aquaculture development. In summary, our new growth records from Hainan Island show that, despite species differences, calcification rates were typical of Indo-Pacific Porites but that in the latter half of the 20th Century, calcification rates have likely responded to both globally and locally induced changes in the marine climate experienced by the corals. KEY WORDS: Porites spp. · Calcification · Growth rates · South China Sea · Temperature · Aquaculture Full text in pdf format Supplementary material PreviousNextCite this article as: Su R, Lough JM, Sun D (2016) Variations in massive Porites growth rates at Hainan Island, northern South China Sea. Mar Ecol Prog Ser 546:47-60. https://doi.org/10.3354/meps11654 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 546. Online publication date: March 21, 2016 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2016 Inter-Research.