CoralTrace – A new approach to understanding climate-induced reef crises

珊瑚礁可能是受到当前气候相关压力(CRS)威胁最大的海洋生态系统。现代珊瑚礁危机表现为大量漂白的频率增加，珊瑚钙化率降低，珊瑚死亡率上升。尽管造礁珊瑚的灭绝风险也很高，但珊瑚礁的衰落是由现有物种净碳酸钙产量的减少推动的，而不是灭绝或灭绝。然而，物种灭绝是一个主要的问题，因为这是不可逆转的，因此阻止了珊瑚礁从CRS驱动的危机中恢复。该项目利用古生物数据库和Erlangen古礁数据库以及一个关于已灭绝的珊瑚礁建造者的新的化石特征数据库，旨在揭示随着时间的推移，珊瑚礁中个体进化命运和整个生态系统变化的相互作用。具体地说，我们检验了三个主要假说：(1)珊瑚礁比造礁物种对CRS更敏感。仅仅因为碳酸钙的净产量减少，全球珊瑚礁危机就可能在没有大规模灭绝的情况下发生。这一假设的一个重要含义是，珊瑚礁危机可能是即将到来的生物多样性危机的早期预警信号。(2)造礁类群的造礁能力和灭绝风险都可以从它们的特征中预测出来。虽然并非所有潜在相关的生活史特征都可以来自化石(例如，光共生体的性质)，但生长形态和栖息地宽度等可保存特征已被证明与今天的珊瑚灭绝风险和珊瑚礁生长相关。(3)中纬和中纬环境是气候危机后珊瑚礁避难和恢复的适宜环境。假设检验将在多变量统计框架和机器学习中进行，重点放在保存的珊瑚礁体积和灭绝作为因变量。独立变量，如升温、缺氧和酸化的幅度和持续时间，将从已公布的来源和伴随的Tersane项目中获得。测试将在特定时间片(二叠纪末、三叠纪末、侏罗纪早期)以及时间序列范围内进行。为了可行并与Tersane的目标相关，CoralTrace将专注于二叠纪至新近纪的珊瑚礁系统。

Coral reefs are perhaps the most threatened marine ecosystems from current climate-related stressors (CRS). The modern reef crisis manifests itself in an increased frequency of mass-bleaching, reduced calcification rates of corals, and elevated coral mortalities. Although extinction risk is also high among reef-building corals, reef decline is driven by reduced net calcium carbonate production of existing species, rather than extirpation or extinction. Nevertheless, extinctions are a major concern, because these are irreversible and thus preventing the recovery of reefs from CRS-driven crises.Using the Paleobiology Database and the Erlangen PaleoReefs Database together with a new fossil trait database on extinct reef builders, this project aims to reveal the interplay of individualistic evolutionary fate and whole ecosystem changes in reefs over time. Specifically, we test three main hypotheses: (1) Reefs are more sensitive to CRS than reef building species. A global reef crisis can occur without mass extinction, simply because the net calcium carbonate production is reduced. An important implication of this hypothesis is that reef crisis may be an early warning sign of a forthcoming biodiversity crisis. (2) Both the reef-building capacity and the extinction risk of reef building taxa can be predicted from their traits. Although not all potentially relevant life-history traits can be derived from fossils (e.g., nature of photosymbionts), preservable traits such as growth morphology and habitat breadth have been shown to be correlated with coral extinction risk and reef growth today. (3) Mesophotic and mid-latitude environments are suitable environments for reefal refugia and recovery after climate induced crises. Hypothesis testing will be performed in a multivariate statistical framework and machine learning focussing on preserved reefal volume and extinction as dependent variables. Independent variables such as magnitude and duration of warming, anoxia and acidification will be taken from published sources and accompanying TERSANE projects. Tests will be conducted at the level of specific time slices (end-Permian, end-Triassic, early Jurassic) as well as in a time-series context. To be feasible and relevant to TERSANE’s goals, CoralTrace will focus on Permian to Neogene reef systems.