Modal analysis of the deep-water solitary scleractinian, Desmophyllum dianthus, on SW Pacific seamounts: inferred recruitment periodicity, growth, and mortality rates
Modal analysis of the deep-water solitary scleractinian, Desmophyllum dianthus, on SW Pacific seamounts: inferred recruitment periodicity, growth, and mortality rates
复制标题
西南太平洋海山深水孤生造石藻 Desmophyllum dianthus 的模态分析：推断的补充周期、生长和死亡率
作者：
R. Thresher;J. Adkins;N. Thiagarajan
由于在珊瑚栖息的极深处工作存在后勤困难，人们对栖息在深海特征的珊瑚的人口统计学知之甚少。为了获得关于这种珊瑚生长、死亡和补充动态的基本信息，我们对在西南太平洋海山采集的广泛分布的独杯珊瑚Desmophyllum diantus的活体捕获标本和亚化石标本的大小和频率分布进行了模态分析。对1997年和2007-2009年收集的活体捕获材料的比较表明，模式随着时间的推移而发展，隐含的最大年龄约为1.9亿年，这与之前使用辐射测量技术确定的石竹的年龄相似。个体数量的对数线性下降进一步意味着恒定的成人死亡率，1997年为每年15.1%，2007-2009年为每年9.2%。2007-2009年样本中大小模式的间隔表明，每隔22至32年就会发生周期性的招募事件，这可能与南大洋大尺度环流的周期性变化有关。对亚化石物质的大小频率分布的初步分析表明，西南太平洋的热带动力、生长和成虫死亡时间表在整个全新世期间基本保持不变。
Little is known about the demography of corals inhabiting deep-sea features due to the logistical difficulties of working at the extreme depths they inhabit. To obtain basic information about growth, mortality, and recruitment dynamics for such a coral, we applied modal analysis to the size frequency distributions of live-caught and sub-fossil specimens of the widely distributed solitary cup coral, Desmophyllum dianthus, collected on SW Pacific seamounts. Comparison of live-caught material collected in 1997 and 2007–2009 indicated modal progression over time and an implied maximum age of approximately 190 years, which is similar to ages determined previously for D. dianthus using radiometric techniques. A log-linear decline in the number of individuals with increasing size further implies a constant adult mortality rate, of 15.1% per annum in 1997 and 9.2% per annum in 2007–2009. The spacing of size modes in the 2007–2009 samples suggests regularly episodic recruitment events, at 22- to 32-year intervals, which may relate to periodic variability in large-scale Southern Ocean circulation. Preliminary analyses of size frequency distributions of the sub-fossil material suggest that the trophodynamics, growth, and adult mortality schedules of D. dianthus in the SW Pacific have remained basically similar throughout the Holocene.