Asian School of the Environment, Nanyang Technological University, Singapore, Singapore.
School of Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK.
Proc Biol Sci. 2020 Jun 24;287(1929):20200541. doi: 10.1098/rspb.2020.0541. Epub 2020 Jun 17.
Global sea-level rise (SLR) is projected to increase water depths above coral reefs. Although the impacts of climate disturbance events on coral cover and three-dimensional complexity are well documented, knowledge of how higher sea levels will influence future reef habitat extent and bioconstruction is limited. Here, we use 31 reef cores, coupled with detailed benthic ecological data, from turbid reefs on the central Great Barrier Reef, Australia, to model broad-scale changes in reef habitat following adjustments to reef geomorphology under different SLR scenarios. Model outputs show that modest increases in relative water depth above reefs (Representative Concentration Pathway (RCP) 4.5) over the next 100 years will increase the spatial extent of habitats with low coral cover and generic diversity. More severe SLR (RCP8.5) will completely submerge reef flats and move reef slope coral communities below the euphotic depth, despite the high vertical accretion rates that characterize these reefs. Our findings suggest adverse future trajectories associated with high emission climate scenarios which could threaten turbid reefs globally and their capacity to act as coral refugia from climate change.
全球海平面上升预计将增加珊瑚礁上方的水深。尽管气候干扰事件对珊瑚覆盖率和三维复杂性的影响已有充分记录，但对海平面上升将如何影响未来珊瑚礁栖息地范围和生物构造的了解有限。在这里，我们使用来自澳大利亚大堡礁中部混浊海域的 31 个珊瑚礁岩芯，并结合详细的底栖生态数据，根据不同海平面上升情景下的珊瑚礁地貌调整，对珊瑚礁栖息地的广泛变化进行建模。模型输出表明，在未来 100 年内，相对于珊瑚礁的相对水深适度增加（代表浓度路径 4.5）将增加低珊瑚覆盖率和通用多样性的栖息地的空间范围。更严重的海平面上升（RCP8.5）将完全淹没珊瑚礁平台，并将珊瑚礁坡珊瑚群落移至光深以下，尽管这些珊瑚礁的垂直堆积率很高。我们的研究结果表明，与高排放气候情景相关的未来轨迹可能对全球混浊珊瑚礁及其作为气候变化珊瑚避难所的能力构成威胁。
