三叠纪—侏罗纪之交(距今约2.01亿年前)的大灭绝事件对海洋生态系统造成重大影响。现有研究表明, 中大西洋火成岩省(CAMP)的大规模火山喷发是此次事件的主要驱动因素, 其引发的碳循环扰动、海平面剧烈波动及海洋酸化等环境压力, 导致海洋底栖生物多样性急剧下降, 其中造礁珊瑚、礁栖海绵及双壳类等底栖类群受创尤为严重。本文基于古生物数据库(PBDB)和Corallosphere数据的系统分析表明, 三叠纪—侏罗纪之交珊瑚的属级分类单元灭绝率高达56.41%。形态学分析进一步揭示, 环境压力导致了明显的选择性灭绝, 高整合度珊瑚(如 Thamnasteroid和Meandroid类群)的灭绝率(91%)显著高于孤立型珊瑚(63%), 而海水碳酸根离子(CO?2?)浓度降低和文石饱和度(Ωarag)下降是制约珊瑚生存、并驱动此形态选择性灭绝的关键环境因素。这些变化直接抑制了造礁珊瑚的钙化能力, 同时破坏了其与虫黄藻的共生关系, 进而导致高整合度珊瑚(依赖共生关系的复杂类群)优先灭绝, 相对应的与之共栖的造礁海绵类也经历了显生宙以来最严重的灭绝事件之一。灭绝事件后, 珊瑚的复苏呈现明显的阶段性: 赫塘期初期, 适应力较强的孤立型或部分低整合度珊瑚率先恢复, 推动了珊瑚多样性的初步回升; 而高整合度造礁珊瑚的全面复苏则延迟至辛涅缪尔期, 且其形态复杂度的恢复显著滞后于分类多样性的恢复。本文的古地理分析表明, 空间分布上, 珊瑚表现出显著的高纬度避难效应——在辛涅缪尔期至普林斯巴期期间, 造礁珊瑚主要分布于＞30°的高纬度地区, 直至普林斯巴期晚期才开始向中低纬度(25°—35°)迁移, 其分布格局与珊瑚礁生态域的坍缩和重建过程高度一致, 但其分布始终未跨越赤道。直到巴柔期全球环境稳定后, 造礁珊瑚才重新在赤道附近繁盛, 标志着珊瑚礁生态系统结构复杂性的完全恢复。本研究通过整合多样性、形态和古地理多维证据, 揭示了三叠纪—侏罗纪之交大灭绝事件对珊瑚动物的生态过滤机制及其长期复苏模式。

The mass extinction event at the Triassic–Jurassic boundary (~201 million years ago) profoundly impacted marine ecosystems. Current research indicates that massive volcanic eruptions of the Central Atlantic Magmatic Province (CAMP) served as the primary trigger for this event. The resulting environmental stresses—including perturbations to the carbon cycle, drastic sea-level fluctuations, and ocean acidification—led to a dramatic decline in marine benthic biodiversity. Among the most severely affected groups were reef-building organisms such as scleractinian corals, reef-dwelling sponges, and bivalves. During this extinction event, corals exhibited distinct phased extinction patterns, with a generic extinction rate of 56.41% and two extinction peaks occurring in the late Rhaetian and late Pliensbachian stages. Environmental analyses indicate that reduced seawater carbonate ion (CO?2?) concentrations and declining aragonite saturation (Ωarag) were critical limiting factors for coral survival. These changes directly inhibited the calcification capacity of reef-building corals and disrupted their symbiotic relationships with zooxanthellae, ultimately leading to the preferential extinction of highly integrated corals (i.e., complex taxa dependent on symbiosis). Concurrently, associated reef-dwelling sponges experienced one of the most severe extinction events in the Phanerozoic. Post-extinction coral recovery displayed clear phasic characteristics. During the early Hettangian, more resilient solitary corals with low levels of morphological integration initiated the recovery process, driving the initial rebound of coral diversity. In contrast, the full recovery of highly integrated reef-building corals was delayed until the Sinemurian. Spatially, corals exhibited a notable high-latitude refuge effect: reef-building corals were predominantly distributed in high-latitude regions (＞30°) and began migrating toward mid- to low-latitudes (25°–35°) areas only in the late Pliensbachian, without crossing into equatorial zones. It was not until environmental conditions stabilized during the Bajocian that reef-building corals re-established flourishing communities in equatorial regions, marking the complete restoration of structural complexity in coral-reef ecosystems.

国家自然科学基金项目(42293280)资助