Data from: Response of deep-sea biodiversity to abrupt deglacial and Holocene climate changes in the North Atlantic Ocean

Aim: Little is known about how marine biodiversity responds to oceanographic and climatic changes over the decadal to centennial time-scales which are most relevant for predicted climate changes due to greenhouse gas forcing. This paper aims to reveal decadal–centennial scale deep-sea biodiversity dynamics for the last 20,000 years and then explore potential environmental drivers. Location: The North Atlantic Ocean. Methods: We investigated deep-sea benthic microfossil records to reveal biodiversity dynamics and subsequently applied comprehensive ecological modelling to test possible environmental factors (i.e. surface productivity, seasonality of productivity or deepwater circulation related to bottom-water temperature) that may have influenced deep-sea biodiversity over these time-scales. Results: Deep-sea biodiversity changed synchronously with stadial–interstadial climate changes over the last 20,000 years across a large area of the North Atlantic in both ostracod crustaceans and foraminiferan protozoa (in spite of their different dispersal abilities). Species diversity rapidly increased during abrupt stadial events during the last deglacial and the Holocene interglacial periods. These include the well-known Heinrich 1, the Younger Dryas and the 8.2 ka events when the strength of Atlantic Meridional Overturning Circulation (AMOC) decreased. There is also evidence for quasi-cyclic changes in biodiversity at a c. 1500-year periodicity, consistent with the well-known ‘1500-year climatic cycle’. Statistical analyses revealed that AMOC variability (probably specifically the variability in AMOC-driven bottom-water temperature) is correlated with deep-sea biodiversity. Main conclusions: Our finding of a significant AMOC–diversity relationship may indicate pervasive control of the diversity of deep-sea benthic species by rapidly changing climate, specifically bottom-water temperature, over decadal to centennial time-scales. Our results, based on highly resolved fossil records, may portend pervasive, synchronous and sudden ecosystem responses to human-induced changes to climate and ocean circulation in this century.

研究目标：目前关于海洋生物多样性如何响应十年至百年尺度的海洋学与气候变化的认知仍较为有限，而该时间尺度恰与温室气体强迫下的预估气候变化最为相关。本研究旨在揭示过去20000年的十年-百年尺度深海生物多样性动态，并探讨潜在的环境驱动因子。
研究区域：北大西洋海域。
研究方法：本研究通过解析深海底栖微化石记录以阐明生物多样性动态，随后运用综合生态模型检验可能影响该时间尺度下深海生物多样性的潜在环境因子，包括表层生产力、生产力季节波动，以及与底层水温相关的深水环流。
研究结果：过去20000年间，北大西洋大范围海域的介形类甲壳动物（ostracod crustaceans）与有孔虫原生动物（foraminiferan protozoa，二者扩散能力存在显著差异）的深海生物多样性，均与冰阶-间冰阶气候变化同步演变。在末次冰消期与全新世间冰期的突变冰阶事件期间，物种多样性快速升高，其中涵盖大西洋经向翻转环流（Atlantic Meridional Overturning Circulation，AMOC）强度减弱的经典海因里希1号事件、新仙女木事件与8.2千年事件。此外，生物多样性存在约1500年周期的准周期变化，与公认的“1500年气候周期”一致。统计分析显示，AMOC变异性（具体可能为AMOC驱动的底层水温变化）与深海生物多样性显著相关。
主要结论：本研究揭示的AMOC与生物多样性间的显著关联，表明在十年至百年尺度上，快速变化的气候（尤其是底层水温）可对深海底栖物种的多样性产生广泛调控作用。基于高分辨率化石记录得到的本研究结果，或预示本世纪人类活动驱动的气候与海洋环流变化，将引发广泛、同步且突发的生态系统响应。