Density banding in corals: barcodes of past and current climate change
Density banding in corals: barcodes of past and current climate change
复制标题
DOI：
10.1007/s00338-013-1056-7
复制
发表时间：
2013-12-01
期刊：
影响因子：
3.5
通讯作者：
Fassoulas, C.
中科院分区：
文献类型：
--
作者：
Brachert, T. C.;Reuter, M.;Fassoulas, C.
预测的未来几十年海表温度（SST）上升可能对珊瑚健康有害，因为石灰质骨架的降水主要取决于SST。温度调节的垂直生长和密度的骨架与季节性SST的变化，导致交替的高密度和低密度带（HDB和LDB）。值得注意的是，HDB和LDB相对于季节的增长率和时间在地理区域内的全球范围内有所不同。在这方面的贡献，我们使用的骨骼密度和季节性解决的氧同位素SST估计从大规模的滨珊瑚从晚中新世（9马）在地中海东部（克里特岛，希腊）的珊瑚礁了解珊瑚礁的脆弱性在短期内和地质时期。HDB与SST的关系有三种类型：（1）HDB与夏季重合，（2）与冬季重合，（3）与秋季和春季重合。后者在一年中的HDB的两倍，并意味着最大钙化耦合到分类特定的最佳SST在过渡季节，并减少在其各自的关键冬季和夏季SST。用非线性温度-钙化关系的模型再现了密度带的气候条形码。该模型应与珊瑚礁和台地中的其他变温碳酸盐生产者相关，并对判断珊瑚、底栖碳酸盐群落和整个碳酸盐系统的地理分布和沉积原因具有影响。关于地质历史中碳酸盐台地和珊瑚礁的扩张和消亡的根本原因，我们希望模型预测有助于更深入地了解高温或冷却期间的生物反应，也可能有助于确定现代海洋中珊瑚濒临灭绝或利用全球变暖的区域。
The predicted sea surface temperature (SST) rise over the next decades is likely hazardous to coral health because precipitation of the calcareous skeleton depends primarily on SST. Temperature modulates vertical growth and density of the skeleton with seasonal SST changes resulting in an alternation of high-density and low-density bands (HDB and LDB). Notably, growth rates and the timing of the HDBs and LDBs relative to the seasons differ on a global scale within geographic regions. In this contribution, we use combined information of skeletal density and seasonally resolved oxygen isotope SST estimates from massive Porites from a Late Miocene (9 Ma) reef in the eastern Mediterranean Sea (Crete, Greece) to understand reef vulnerability over short and geological periods of time. Three types of HDB-SST relationships have been found: (1) coincidence of HDB with summer, (2) winter or (3) autumn and spring. The latter doubles HDBs in a year and implies maximum calcification is coupled to the taxon-specific optimum SST during the transitional seasons and reduced at its respective critical winter and summer SSTs. Modeling with a nonlinear temperature-calcification relationship reproduces the climate barcode of density bands. The model should be relevant for other poikilothermic carbonate producers in reefs and platforms and has implications for judging geographic distributions and causes of extinctions of corals, benthic carbonate communities and entire carbonate systems. With regard to the causes underlying expansion and demise of carbonate platforms and reefs in geological history, we expect the model predictions to help for a deeper understanding of biotic responses during hyperthermals or coolings and possibly also for identifying regions in the modern ocean where corals are endangered or taking advantage of global warming.