The unprecedented loss of Florida's reef‐building corals and the emergence of a novel coral‐reef assemblage
The unprecedented loss of Florida's reef‐building corals and the emergence of a novel coral‐reef assemblage
复制标题
佛罗里达州造礁珊瑚的空前损失和新型珊瑚礁组合的出现
作者：
L. Toth;A. Stathakopoulos;I. B. Kuffner;R. Ruzicka;M. Colella;E. Shinn
摘要在过去的半个世纪里，气候变化、珊瑚礁疾病和其他人为干扰在全球范围内重构了珊瑚礁生态系统。曾经占主导地位的造礁类群的不成比例的丧失，促进了“杂草”或耐压力珊瑚物种数量的相对增加。尽管最近珊瑚礁组合的变化在生态时间尺度上是史无前例的，但要确定现代珊瑚礁是否真的达到了一种新的生态系统状态，需要评估更长时间内珊瑚礁组成的动态。在这里，我们通过使用在整个佛罗里达群岛珊瑚礁区(FKRT)收集的59个全新世珊瑚礁岩芯重建珊瑚礁组合中千年尺度的空间和时间变异性，从地质学的角度提供了佛罗里达州珊瑚礁组成的变化。然后，我们将全新世珊瑚礁框架中造礁物种的相对丰度与当代珊瑚礁调查的数据进行比较，以确定佛罗里达州现代珊瑚礁组合与长期基线的偏离程度。我们发现，直到最近，佛罗里达珊瑚礁的组成在过去的8000年里都非常稳定。几十万年来在西大西洋的浅水礁上占据主导地位的珊瑚--棕榈珊瑚、奥比氏菌和其他大型珊瑚类群--占佛罗里达州全新世珊瑚礁结构的近90%。相比之下，目前在FKRT上相对丰度最高的物种，主要是Porites astreoides和Siderastrea siderea，在珊瑚礁框架中是罕见的，这表明最近物种组合的变化在千年时间尺度上是前所未有的。尽管珊瑚礁可能不可能恢复到人类世以前的状态，但我们的结果表明，珊瑚礁管理侧重于保护和恢复过去的造礁物种，将优化保护珊瑚礁的努力，并为未来提供宝贵的生态系统服务。
Abstract Over the last half century, climate change, coral disease, and other anthropogenic disturbances have restructured coral‐reef ecosystems on a global scale. The disproportionate loss of once‐dominant, reef‐building taxa has facilitated relative increases in the abundance of “weedy” or stress‐tolerant coral species. Although the recent transformation of coral‐reef assemblages is unprecedented on ecological timescales, determining whether modern coral reefs have truly reached a novel ecosystem state requires evaluating the dynamics of reef composition over much longer periods of time. Here, we provide a geologic perspective on the shifting composition of Florida's reefs by reconstructing the millennial‐scale spatial and temporal variability in reef assemblages using 59 Holocene reef cores collected throughout the Florida Keys Reef Tract (FKRT). We then compare the relative abundances of reef‐building species in the Holocene reef framework to data from contemporary reef surveys to determine how much Florida's modern reef assemblages have diverged from long‐term baselines. We show that the composition of Florida's reefs was, until recently, remarkably stable over the last 8000 yr. The same corals that have dominated shallow‐water reefs throughout the western Atlantic for hundreds of thousands of years, Acropora palmata, Orbicella spp., and other massive coral taxa, accounted for nearly 90% of Florida's Holocene reef framework. In contrast, the species that now have the highest relative abundances on the FKRT, primarily Porites astreoides and Siderastrea siderea, were rare in the reef framework, suggesting that recent shifts in species assemblages are unprecedented over millennial timescales. Although it may not be possible to return coral reefs to pre‐Anthropocene states, our results suggest that coral‐reef management focused on the conservation and restoration of the reef‐building species of the past, will optimize efforts to preserve coral reefs, and the valuable ecosystem services they provide into the future.
影响因子：
5.7
作者：
Guest, James R.;Edmunds, Peter J.;Toth, Lauren T.
通讯作者：
Toth, Lauren T.
影响因子：
7.7
作者：
Muller EM;Bartels E;Baums IB
通讯作者：
Baums IB