陆地生态系统演变对晚三叠世卡尼期洪泛事件的响应过程和模式^*

Response processes and patterns of terrestrial ecosystems to the Late Triassic Carnian Pluvial Episode

摘要

晚三叠世卡尼期洪泛事件(Carnian Pluvial Episode,CPE,~234—232 Ma)以全球温度和湿度的急剧上升为特征,伴随着海洋和陆地生态系统的显著变化,并与兰格利亚大火成岩省的喷发有关。目前大量有关CPE的研究主要集中在地层约束良好的海相地层中,而陆地生态系统对CPE事件响应过程的研究有限。本研究回顾了CPE期间陆地环境-气候和植物变化的研究现状,并对其潜在驱动机制进行了探讨。几乎同步出现的多次碳同位素负偏移(CIEs)与Hg富集异常(Hg/TOC峰值)和Hg同位素证据,提供了兰格利亚大火成岩省是CPE期间陆地环境、气候和生物显著变化驱动因素的直接证据。兰格利亚大火成岩省喷发释放的大量CO₂引发全球变暖,导致大气环流与水文循环增强,促使全球降雨量增加和气候由暖干转向暖湿。这些变化造成陆地上三角洲和沼泽广泛发育、湖平面上升、化学风化作用加剧、湿生植物和淡水藻类增多、全球聚煤作用再现,以及针叶类植物、恐龙、昆虫、鳄鱼、海龟、哺乳类动物等的起源和辐射。同时,陆地风化作用增强、地表水系扩张及湿生植物与淡水藻类增加,推动了陆地有机碳埋藏量显著上升,这有助于全球聚煤作用重现。而有机碳埋藏量增加和全球聚煤作用再现可对改善全球大气条件形成负反馈,部分抵消兰格利亚大火成岩省释放温室气体引发的温室效应,促使CPE期间环境和气候渐趋稳定,最终致使CPE事件终止。这些结果表明大火成岩省可以以多个脉冲形式发生,并改变碳循环、引起环境和气候变化、驱动生物宏观进化,而全球性聚煤作用则在气候稳定性方面发挥着至关重要的作用。

Abstract

The Late Triassic Carnian Pluvial Episode(CPE,~234-232 Ma)is characterized by a sharp increase in global temperature and humidity,accompanied by significant changes in marine and terrestrial ecosystems,and is associated with the eruptions of the Wrangellia Large Igneous Province(LIP). Much of the current research on CPE has focused on marine strata with well-constrained stratigraphy,while research on the response processes of terrestrial ecosystems to CPE has been limited. Here,we review the status of terrestrial environmental,climatic,and plant changes during the CPE and explore its potential driving mechanisms. The evidence of multiple nearly synchronous negative carbon isotope excursions(CIEs),mercury(Hg)enrichment anomalies(peaks in the Hg/TOC ratio),and Hg isotopes provides direct evidence that the Wrangellia LIP was a driving factor for the significant changes in terrestrial environment,climate,and biology during the CPE. The eruption of the Wrangellia LIP released a large amount of CO₂,triggering global warming. This has led to enhanced atmospheric circulation and hydrological cycles,promoting increased global rainfall and a shift in climatic conditions from relatively warm and dry to relatively warm and humid. These conditions have resulted in the extensive development of terrestrial deltas and swamps,the rise of lake levels,the intensification of chemical weathering,the increase of hygrophytic plants and freshwater algae,and the re-emergence of global coal accumulation,as well as the origin and radiation of dinosaurs,coniferous plants,insects,crocodiles,turtles,and mammals. Terrestrial weathering,the expansion of surface water systems,and an increase in hygrophytic plants and freshwater algae have driven a significant rise in the amount of terrestrial organic carbon buried,contributing to the resurgence of global coal accumulation. The increase in the amount of organic carbon buried and the re-emergence of global coal accumulation have created negative feedback on the improvement in global atmospheric conditions. This can counteract the greenhouse effect caused by the release of greenhouse gases from the Wrangellia LIP,facilitate the gradual stabilization of the environment and climate during the CPE,and ultimately lead to the termination of the CPE. These results suggest that LIP can occur in multiple pulse forms and have a powerful ability to alter the carbon cycle,trigger environmental and climatic changes,and drive macroevolution of organisms. On the other hand,global coal accumulation plays a crucial role in climate stability.

Graphical abstract

关键词

晚三叠世 / 卡尼期洪泛事件 / 陆地生态系统 / 聚煤作用 / 兰格利亚大火成岩省

Key words

Late Triassic / Carnian Pluvial Episode / terrestrial ecosystem / coal accumulation / Wrangellia Large Igneous Province

0 引言

晚三叠世气候长期干旱,被一次极端湿润事件所中断,即卡尼期洪泛事件(Carnian Pluvial Episode,CPE,~234—232 Ma)(Simms and Ruffell,1989;Dal Corso et al., 2020;Lu et al., 2021)。此次事件是自二叠纪—三叠生物危机后缓慢且长期恢复的重要转折,被誉为现代生态系统的黎明和曙光(Dal Corso et al., 2020)。CPE的特征表现为全球温度升高、降雨量的显著增加以及湿润化气候盛行(金鑫等,2015;Dal Corso et al., 2020),同时伴随着碳循环波动(王艳艳等,2013;Sun et al., 2016;Miller et al., 2017;Dal Corso et al., 2018,2020;Lu et al., 2021;Li et al., 2022b)、碳酸盐工厂的关闭(时志强等,2009;Jin et al., 2018,2020)、海洋/湖泊缺氧(Sun et al., 2016;Dal Corso et al., 2020;Lu et al., 2021)、生物灭绝率较高(包括菊石、牙形石和海百合)及生物多样性增加(包括针叶树、恐龙、钙质超微化石等)(Simms and Ruffell,1989;Bernardi et al., 2018;Dal Corso et al., 2020)。时间上的耦合表明,CPE事件可能主要与兰格利亚大火成岩省的喷发有关,该火山喷发向大气—海洋系统中释放出大量CO₂,导致全球大气环流和水文循环增强(Dal Corso et al., 2020;Lu et al., 2021;Mazaheri-Johari et al., 2021;Zhao et al., 2022;Jin et al., 2023)。

晚三叠世CPE事件期间的环境-气候变化研究主要集中在地层约束良好的海相地层中,而它们在陆相地层中的记录和表现还有待进一步研究(e.g.,Dal Corso et al., 2020;Coram and Radley,2023;赵向东等,2024)。陆地不仅是地球表层的重要组成部分和动植物的重要栖息地,也是海洋系统沉积物和营养物质的主要来源,对其开展研究可能是揭示极端重大气候事件期内环境-气候变化原因的关键(Dal Corso et al., 2020;Lu et al., 2020,2021)。其次,相对于海洋生态系统而言,陆地生态系统对极端环境-气候事件的适应能力有限,容易遭受严重程度更高、持续时间更久且不可恢复的影响和灾害(e.g.,Zhang et al., 2025)。此外,晚三叠世卡尼期的全球性聚煤作用(以厚煤层为主),代表了自晚二叠世末期聚煤作用中断之后的再次开始(Retallack et al.,1996; Dal Corso et al., 2020;Zhang et al., 2023),不仅提供了丰富的能源矿产资源,同时聚煤作用本身也是一个全球性的环境-气候事件(e.g.,鲁静等,2016;Shao et al., 2020)。因此,许多学者逐渐将研究重点聚焦于全球不同地区所涉及的主要陆地生态系统演变与CPE事件耦合关系上,但目前对于全球陆地生态系统对CPE事件的响应过程和模式依旧缺乏系统性分析。

在本研究中,笔者系统地回顾和总结了目前已知的CPE期间全球陆地生态系统演变的证据,用以评估陆地生态系统变化对CPE事件的响应过程和模式。在此基础上,进一步探讨和分析兰格利亚大火成岩省对CPE期间陆地生态系统演变的驱动机制。

1 CPE的年龄限制及持续时间

现有的CA-TIMS锆石测年数据和生物地层证据显示,CPE事件主要发生在~234 Ma至232 Ma之间(Benton et al., 2018;Dal Corso et al., 2020)(图1)。来自特提斯洋西部冈瓦纳大陆,即阿根廷Ischigualasto-Villa Unión盆地的CA-TIMS测年数据和其他沉积学、矿物学、碳氧同位素的综合证据显示,CPE事件发生在234.47±0.44 Ma之后(Mancuso et al., 2020),该结果也被来自巴西圣玛丽亚(Santa Maria)组的CA-TIMS测年结果(233.23±0.73 Ma)和生物地层证据所支持(Langer et al., 2018)。此外,冈瓦纳大陆具有代表性的Ischigualasto组中记录的恐龙多样化事件发生在CPE之后(Benton et al., 2018),并进一步得到了来自上部地层~231.4 Ma这一锆石测年结果的支持(Martínez et al., 2011),这也意味着CPE事件的结束可能发生在~232 Ma。

现有的生物地层(包括菊石、牙形石和孢粉化石)和化学地层(碳同位素地层)证据提供了识别和确认CPE事件在海相、海陆过渡相和陆相地层中开始(启动)的标志(Dal Corso et al., 2018,2020)。CPE事件的开始与菊石Austrotrachyceras属在Julian亚期的首次出现相一致(Simms and Ruffell,1989;Dal Corso et al., 2012,2015;Sun et al., 2016),并伴随着首次碳同位素组成负偏移(CIE-I)(Dal Corso et al., 2018,2020)和陆地湿生植物的增加(Mueller et al., 2016a;Lu et al., 2021)。此外,生物地层与高分率碳同位素曲线的对比表明,碳同位素组成负偏移贯穿整个CPE期间,并以3或4次负偏移为特征(Miller et al., 2017;Dal Corso et al., 2018;Lu et al., 2021;Tomimatsu et al., 2021;Li et al., 2022b)。尽管锆石TIMS测年结果和生物地层的证据揭示CPE事件可能结束于232 Ma(Martínez et al., 2011;Benton et al., 2018),但由于缺乏更高分辨的地层年代学研究,其结束时间仍存在一定争议。根据沉积学(碎屑沉积物供应的结束)和碳同位素地层(最后一次CIE)的证据,目前将CPE的结束时间置于Tuvalian 2亚期的底部或内部(Dal Corso et al., 2020;Lu et al., 2021)。

现有的年代地层学、旋回地层学、生物地层学和磁性地层学证据显示,CPE事件发生在~234—232 Ma,持续了1.09~1.7 Myr(Zhang et al., 2015;Miller et al., 2017;Bernardi et al., 2018;Lu et al., 2021)。在华南地区,利用沉积学(富碳酸盐岩向富碎屑岩转变)、磁性地层(反转极性区间)和旋回地层(自然伽马强度曲线的405 ka偏心率周期旋回)证据对CPE持续时间进行了约束,结果显示CPE可能持续了约1.3 Myr(Zhang et al., 2015)。在英国,利用碳同位素地层(CIEs)和旋回地层(Ca/Ti值的405 kyr偏心率周期旋回)的证据对CPE持续时间进行了约束,结果表明CPE可能持续了约1.09 Myr(Miller et al., 2017)。在意大利,利用沉积学(由4次流入盆地内部的碎屑物质突然增加推断的显著湿润脉冲)、碳同位素地层(4次显著的CIEs)和生物地层(由Aonoides/Austriacum和Subbullatus限制和约束)对CPE持续时间进行了约束,结果表明CPE持续了1.6~1.7 Myr(Bernardi et al., 2018;Dal Corso et al., 2018)。在华北地台,利用生物地层(孢粉化石种类、湿生植物增加)、碳同位素地层(4次显著的CIEs)、2个锆石U-Pb定年数据(233.1±1.3 Ma和232.9±2.1 Ma)对CPE持续时间进行了约束,结果显示CPE持续了约1.6 Myr(Lu et al., 2021)。

此外,特提斯洋西部的西欧盆地和特提斯洋东部的鄂尔多斯盆地均被认为是较好记录CPE事件的重要陆相区域。然而,现有的CPE事件持续范围主要依赖碳同位素波动(4碳同位素负偏移)和古植物类型变化进行约束(e.g.,Dal Corso et al., 2018;Baranyi et al. 2019a,2019b),锆石定年数据结果仍存在不确定性。在特提斯洋西部地区,卡尼期可靠的锆石U-Pb定年数据显示CPE结束时间早于230.91±0.33 Ma(Furin et al., 2006),但该年龄并不能作为支持CPE结束的强有力地质年代证据。在特提斯洋东部的华北地台鄂尔多斯盆地,不同研究地点和不同分析方法(包括激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)、高分辨率离子探针质谱法(SHRIMP)、同位素稀释热电离质谱法(ID-TIMS))获得的测年结果显示延长组7段锆石定年的分析结果并不相同(e.g.,Jin et al., 2021;Rahman et al., 2024)。来自山西永和交口剖面延长组7段下部的同一样品通过SHRIMP方法得到的锆石U-Pb年龄为238.6±2.6 Ma,而同位素稀释热电离质谱法得到的锆石U-Pb年龄为241.369±0.06 Ma(Liu et al., 2013,2018)。同样地,来自衣食村剖面延长组7段下部相似层位的样品利用LA-ICP-MS方法得到的锆石U-Pb年龄为239.7±2.7 Ma,而ID-TIMS方法得到的锆石U-Pb年龄为241.558±0.093 Ma(Zhu et al., 2019)。尽管ID-TIMS方法与LA-ICP-MS和SHRIMP方法相比,相对误差更小,但其加权平均年龄主要是基于少数锆石年龄得到的(Zhu et al., 2019)。其次,由于鄂尔多斯盆地可能存在不同的沉积中心,造成凝灰岩沉积后发生了迁移,从而导致不同剖面和钻孔中的凝灰岩年龄结果存在差异。此外,鄂尔多斯盆地已发表的大多数锆石测年结果、天文旋回分析和碳同位素地层的综合分析结果表明,长7₃段下部属于拉丁期,而长7₂和长7₁段属于卡尼期(e.g.,张文等,2017;Lu et al., 2022;Li and Yang,2023;Rahman et al., 2024)。然而,由于鄂尔多斯盆地拉丁期—卡尼期的地层发育情况不同,某些剖面的长7段可能存在穿时沉积和沉积间断(e.g.,Rahman et al., 2024)。

2 与CPE相关的陆地环境演变

CPE事件显著改变了全球陆地沉积环境。在中欧大陆盆地,晚三叠世卡尼期出现了由干盐湖和萨布哈(Sabkha)湖泊向河流、淡水湖泊以及沿岸潟湖环境的转变,这意味着陆地水文循环显著增强(Simms and Ruffell,1989;Arche and López-Gómez,2014)。来自德国斯图加特(Stuttgart)组和其他区域同地层单元的沉积记录显示,晚三叠世出现了大型河流系统(Kozur and Bachmann,2010),而这种大型河流系统也在同时期的整个欧洲广泛出现,其中CPE期间在挪威北部地区形成了已知地质历史时期上面积最大的三角洲(1,000,000 km²)(Klausen et al., 2019)。在北大西洋裂谷阶段从格陵兰岛到摩洛哥形成了一个复杂的古环境系统,其由相互连接的内陆盆地组成,在这些盆地中卡尼期的沉积物以湖泊沉积为主,包括煤炭沉积,但缺乏蒸发盐沉积(Ruffell et al., 2016)。在东格陵兰岛,较深的淡水湖泊或者浅海沉积物覆盖了之前的河流和/或风成沉积物(Andrews and Decou,2019)。在北美东部的纽瓦克盆地,出现了巨大的河流和湖泊(Olsen,1997;Olsen et al., 2015)。在摩洛哥出现了河流或大型湖泊沉积,取代了之前以蒸发盐为主的干旱沉积(Mader et al., 2017)。在阿根廷的Ischigualasto盆地出现由河流环境向湖泊环境的转变(Ezcurra et al., 2017;Bernardi et al., 2018),相似的环境变化也被巴西的Santa Maria组到Caturrita组沉积物所记录(Mietto et al., 2012)。在华北地台,晚三叠世卡尼期形成了当时已知的受地表水补给的全球最大淡水湖泊(鄂尔多斯古湖)(Chen et al., 2021),且该湖泊经历了明显的收缩—扩大过程(Chen et al., 2021; Lu et al., 2021)。上述陆相地层中记录的类似时期的地质事件表明,晚三叠世卡尼期全球水文循环增强和降雨量的增加导致了流域的广泛扩张,汇成湖泊或沼泽。然而,由于这些陆相地层缺少可靠且更高分辨率的综合地层年代框架约束,全球湖泊/沼泽扩张机制与CPE的联系还有待进一步研究(e.g.,Dal Corso et al., 2020)。

CPE事件伴随着全球碳循环的显著波动(图1),并以反复的碳循环扰动(3或4次CIEs)为特征(图2)。CPE事件的开始与首次全球碳循环扰动同步发生(Dal Corso et al., 2020),这已被来自不同纬度和地区的各种环境(包括深海相、浅海相、海陆过渡相、湖泊环境)中的沉积物记录所证实,而随后出现的多次CIEs也在意大利、匈牙利、英国、中国华南地区和特提斯洋西北部的沉积所记录(Sun et al., 2016;Miller et al., 2017;Dal Corso et al., 2018,2020;Lu et al., 2021;Li et al., 2022b;Lestari et al., 2024;Rahman et al., 2024)(图2)。这些CIEs叠加在晚三叠世碳酸盐岩和有机质记录的碳同位素长期正偏移中(Dal Corso et al., 2012,2015),这一正偏移趋势被归因于早三叠世“煤隙”之后重新出现的煤沼泽和泥炭地及其伴随的有机质埋藏量逐渐增加(全球¹²C固存增加)(Korte et al., 2005;Zhang et al., 2023)。此外,陆地生态系统作为全球碳循环的重要组成部分,其变化模式对于正确识别和理解CPE事件至关重要。近年来,基于锆石测年、旋回地层和生物地层的证据,CPE期间陆地有机碳同位素组成变化在英国德文郡(Devon)(Miller et al., 2017)、中国华南秭归盆地(Li et al., 2022b)、澳大利亚塔斯马尼亚东部(Lestari et al., 2024)、中国华北济源盆地(Lu et al., 2021)和鄂尔多斯盆地(Rahman et al., 2024)均有所记录。尽管不同地区陆相地层中的有机碳同位素组成的采样分辨率、负偏移次数和幅度均有所差异(图2),但仍可以为全球CPE期间的碳同位素扰动和模式对比提供关键证据。

CPE事件期间,全球水循环增强,促进了大陆化学风化作用的显著增强。前人对特提斯洋西部地区的化学风化指数和黏土矿物以及同时期的湿生植物组成和冈瓦纳大陆西部巴西帕兰盆地的CIA等相关数据的分析发现,CPE期间更加湿润的气候条件促进了大陆化学风化作用的显著增强(Rostási et al., 2011;Horn et al., 2018;Baranyi et al., 2019a,2019b;Pecorari et al., 2023)。来自特提斯洋西部地区海相地层记录的CPE期间4个陆地沉积物供应增加的间隔,可以解释为周期性湿润气候条件引起的陆地径流增加和大陆风化作用增强(Hornung and Brandner,2005;Dal Corso et al., 2015,2018)。

在特提斯洋东部地区,华北地台济源盆地CPE期间的地球化学和矿物学数据记录了4次增强的大陆化学风化作用,并与CIEs、Hg富集异常和湿生植物增加同步出现(Zhang et al., 2024a)。值得注意的是,特提斯洋西部地区的大陆风化作用与CIEs并不同步(Pecorari et al., 2023),这种时间上的差异可能主要与陆相高岭石源区和海洋沉积环境之间的距离有关。

3 与CPE相关的陆地植物区系和气候条件演变

现有研究表明,CPE期间增强的水文循环导致了陆地植物区系和气候条件发生显著变化(图3),即植物由旱生植物区系转向湿生植物区系,以及气候由相对凉爽干燥转向相对温暖湿润(Dal Corso et al., 2020,2022;Zhang et al., 2024a)。该时期显著改善的气候条件促进了植物类群(包括本内苏铁目(Bennettitales)、针叶类(conifers)、膜蕨科(Hymenophyllaceae)、罗伞蕨科(Matoniaceae)和双扇蕨科(Dipteridaceae))的辐射和多样化,也成为中生代和现代植物类群的重要组成部分(Dal Corso et al., 2020;Roghi et al., 2022;Zhang et al., 2023)(图3)。

晚三叠世卡尼期的植物化石记录比较零星,通常只能识别到期的水平,这意味着对CPE阶段内植物面貌和类型多样化的演变过程并不能准确地追踪(Dal Corso et al., 2020)。尽管如此,在晚三叠世卡尼期的植物群中仍出现了明显的旱生植物向湿生植物的转变(Roghi,2004;Roghi et al., 2010;Baranyi et al., 2019b)。在冈瓦纳大陆,陆地大型植物区系以棒状种子蕨类植物为主,孢粉化石可以分为较暖的Ipswich北部植物区系和较冷的Onslow植物区系(Kustatscher et al., 2018)。在Laurasia地区,陆地植物在卡尼期发生从干旱化区系向湿润区系的转变,并伴随着厚煤层的出现(Pott et al., 2008),这意味着全球性聚煤作用的再次出现,已从二叠纪—三叠陆地生态系统崩溃引起的全球性聚煤间断中完全恢复(Retallack et al., 1996;Zhang et al., 2023)。在欧洲,奥地利Lunz植物区系是卡尼期植物区系的代表,在CPE期间以蕨类和苏铁/本内苏铁目植物为主,常见楔叶类植物,银杏和针叶类植物丰度相对较低(Pott et al., 2008;Mueller et al., 2016a;Kustatscher et al., 2018)。在中国华南地区,卡尼期植物以川滇地区的大荞地植物区系和湖北九里岗植物区系为代表,主要包括楔叶类(Sphenophytes)和蕨类(Ferns)植物,常见种子蕨(Seed ferns)和苏铁/本内苏铁目(Cycads/Bennettitaleans)植物(周统顺和周惠琴,1983)。在中国华北地台,延长组以旱生植物区系(以Voltzia为主)的消失为特征,并反映了可能与CPE事件有关的相对湿润的气候条件(Sun et al., 2020)。

然而,由于植物大化石在埋藏过程中容易受到不同沉积环境的影响而出现埋藏偏差(DiMichele et al., 2020),再加上相对较低的植物大化石分辨率(样品数量较少),其可能不会完全反映出CPE期间的植物面貌及其多样性的变化趋势。

前人研究表明,孢粉化石不会像大植物化石那样受到生境异质性的影响(Marchetti et al., 2022),因此,孢粉化石在一定程度上更能准确地反映CPE期间的植物面貌和多样性的演变过程。西特提斯洋地区的孢粉学研究显示了CPE期间显著的植物类型变化(图3): 在意大利东北部地区,从Julian晚期到Tuvalian早期,蕨类孢子和石松孢子丰度增加,指示盛行相对湿润的气候条件(Roghi,2004); 在挪威北部地区,蕨类孢子丰度升高,煤层出现在Julian晚期的De Geerdalen组,表明此时盛行相对温暖湿润的气候条件(Hounslow et al., 2007;Mueller et al., 2016b); 在奥地利,Julian 2亚期的湿生植物丰度和湿生植物/旱生植物(H/X)值的增加,表明此时相对湿润气候条件盛行以及水循环加剧(Roghi et al., 2010;Mueller et al., 2016a)(图4-a); 在匈牙利西部,Julian 2亚期的H/X值和高岭石含量升高,表明该时期地表径流密集、降雨量增加且盛行相对湿润气候条件(Dal Corso et al., 2018;Baranyi et al., 2019b)(图4-a); 在波兰,CPE期间出现从旱生植物区系向湿生植物区系的明显转变,同时古土壤出现从旱地土壤向排水不良土壤的转变,意味着相对湿润气候条件盛行(Fijałkowska-Mader et al., 2021); 在伊朗东北部的Aghdarband盆地,Miankuhi组最下部的湿生蕨类孢子和煤层占据主导,表明此时盛行相对湿润的气候条件(Mazaheri-Johari et al., 2022)。然而,来自丹麦盆地和英国威塞克斯盆地的孢粉化石研究却缺失了CPE期间相对湿润的气候信号(Lindström et al., 2017;Baranyi et al., 2019a),这可能与其地处的内陆地区过于干燥的气候条件或干旱植物比例过高有关,也可能反映了温度升高背景下区域性气候存在差异。

东特提斯洋地区的孢粉学研究同样显示了CPE期间显著的植物变化: 在华北地台济源盆地,从Julian 2到Tuvalian早期,蕨类孢子(包括Cyclogranisporites、Osmundacidites、Punctatisporites)和淡水藻类(包括 Leiosphaeridia、Granodiscus、Verrucosphaera tuberculata、Micrhystridium)的相对丰度以及H/X值出现显著增加,指示此时盛行相对湿润的气候条件(Lu et al., 2021)(图4-a); 在华南地区,马鞍塘组记录了Julian 2亚期蕨类植物(特别是 Dipteridaceae/Matoniaceae)和H/X值的显著增加,表明此时盛行相对湿润的气候条件(Li et al., 2022a)(图4-a); 在中国西北地区的准格尔盆地,黄山街组记录了卡尼期的植物群落从以针叶林为主转向以蕨类为主,揭示了CPE期间盛行相对湿润的气候条件(Peng et al., 2022)。然而,由于孢粉化石记录缺乏温度的指示因子(Fijałkowska-Mader et al., 2021;Li et al., 2022a; Zhang et al., 2024a),暂时无法利用孢粉化石来判断CPE期间的古温度变化。

尽管晚三叠世卡尼期全球不同地区的氧同位素分辨率不同,但现有的证据表明CPE是一个变暖事件(Trotter et al., 2015;Sun et al., 2016)(图3)。来自特提斯洋西部Calcareous Alps北部和Lagonegro盆地的氧同位素证据记录了Julian晚期到Tuvalian亚期的6~8 ℃变暖事件(Hornung et al., 2007a; Trotter et al., 2015)(图3)。来自特提斯洋东部华南地区南盘江盆地的氧同位素证据记录了Julian 2亚期和Tuvalian 1亚期的2次变暖事件,温度上升幅度分别约为4 ℃和6 ℃(Sun et al., 2016)(图3)。此外,基于全球碳同位素组成和Hg浓度(Hg/TOC值)的生物地球化学模型的模拟结果显示,CPE期间出现了4次增温约5 ℃的温暖事件(Dal Corso et al., 2022)。在华北地台,利用化学风化蚀变指数(CIA)和古温度关系式重建的古温度结果也进一步提供了4次增温(增温幅度变化在3.1~4.1 ℃之间)的证据(Zhang et al., 2024a)。综上所述,CPE期间全球出现了多次相对暖湿盛行的气候条件,每次气候的变化都促进了陆地植物类型从旱生植物向湿生植物转变。

4 与CPE相关的其他陆地生物演变

早期研究认为,CPE事件期间喙龙类(Rhynchosaurs)灭绝率显著增加(Benton,1991;Dal Corso et al., 2020),然而来自阿根廷拉里奥哈地区(La Rioja)最新的高分辨率锆石定年结果显示,喙龙类一直生存到卡尼期末(也可能延续到了最早的诺利期)(Desojo et al., 2020)。其他的四足动物群,如半水生、类似鳄鱼的两栖动物(temnospondyl),即使幸存下来,在三叠纪后期也逐渐出现衰落(Schoch,2013),然而由于其衰减性质,很难将这种下降与CPE事件进行有效连接。中大型食草动物二齿兽类(dicynodonts)在CPE之后丰度出现显著下降,但其类群一直持续存在到诺利期,也可能持续到晚三叠世末期(Racki and Lucas,2020)(图3)。来自南美洲的证据显示,二齿兽类种类的变化确实可以反映气候波动,但相对而言湿润气候对二齿兽类的影响有限(Kammerer and Ordoñez,2021)。目前北半球尚没有发现晚三叠世卡尼期二齿兽类化石的有效证据,故无法评估二齿兽类在这些区域的变化(Lucas,1993;Tverdokhlebov et al., 2003)。因此,CPE事件是否显著促进了二齿兽类的衰落,仍需要更多的证据来证实。尽管如此,二齿兽类中的Kanneymeriidae科可能在卡尼期已经灭绝(Kammerer et al., 2013)。

除了四足动物的灭绝和衰减之外,许多四足动物分支出现了明显的辐射,在地理分布上变得更加广泛(图3)。来自德国、南美洲、非洲南部和北欧等地的化石记录显示,这些四足动物主要包括类似鳄鱼的植龙类(phytosaurs)、植食的铠甲龙类(armoured)和恩吐龙类(aetosaurs)、喙头目爬行动物(rhynchocephalians)等(Stocker et al., 2017; Desojo et al., 2013;Hsiou et al., 2019)(图3)。事实上,就之后的生态学和进化成功而言,最主要的是恐龙类的多样化事件(图3)。来自特提斯洋西部欧洲地区的化石记录显示,恐龙足迹在CPE期间出现显著增加,并在CPE之后占据优势地位(图3;图4-b),表明CPE期间温暖湿润的气候条件促进了恐龙的辐射演化(Benton et al., 2018;Bernardi et al., 2018)。

除了恐龙辐射事件以外,CPE事件似乎还促进了海龟和哺乳动物的起源和发展。来自特提斯洋东部的中国华南地区法郎组瓦窑段的化石,记录了具有完全发育的腹面和神经板组成的背甲壳形成早期阶段的齿龟(Odontochelys)(Li et al., 2008)。在特提斯洋西部的德国Löwenstein组(诺利期),发现了甲壳完全发育的海龟(Gaffney,1990),其起源可追溯到早三叠世(Lichtig et al., 2018)。随后对伊比利亚半岛(Iberian Peninsula)Manuel组沉积物的研究表明,CPE期间形成的大规模淡水湖泊系统和丰富的营养资源以及生态位空间,引发了卡尼期海龟的辐射(Arche and López-Gómez,2014)。此外,来自印度Rewa盆地(Datta,2005)和美国得克萨斯州(Lucas,1993)的化石记录表明,哺乳动物也可能起源于卡尼期,随后在诺利期出现了多样化,并在英国、德国、格陵兰岛和卢森堡等地区出现了摩根齿兽类(morganucodontans)、贼兽类(haramiyids)、对齿兽类(symmetrodonts)等哺乳动物化石(Kielan-Jaworowska et al., 2016)(图3)。

CPE事件在陆地环境中的另一个不同寻常之处在于,它标志着琥珀首次出现于化石记录中,并广泛分布于北纬5°~30°之间(e.g.,Dal Corso et al., 2020)(图3)。来自于欧洲意大利年代地层约束较好的琥珀化石记录揭示其主要形成于CPE期间(Seyfullah et al., 2018),但其他大陆琥珀化石的年代仍不确定(Dal Corso et al., 2020)。来自意大利白云岩的琥珀化石保存了最古老的四足植食性螨类(phytophagous mites)(Sidorchuk et al., 2015),螨类的不同形态则表明CPE期间它们是一个繁荣的群体,这揭示了现代食草昆虫进化的重要一步,也是水生昆虫、水甲虫(water beetles)和隐翅虫(rove beetles)在内的昆虫多样化事件的一部分(Labandeira,2000;Nicholson et al., 2015)。来自南非卡鲁盆地的琥珀化石记录也揭示了卡尼期食草昆虫的扩张(Labandeira,2006)。然而,尽管特提斯洋东部地区在CPE 时期存在温暖潮湿气候条件(e.g.,Sun et al., 2020;Lu et al., 2021;Li et al., 2022a),有利于植物生长和树脂分泌,理论上也具备形成琥珀的条件,但目前尚没有在特提斯洋东部地区发现琥珀化石。此外,许多“现代”节肢动物的进食方式,包括穿刺和吸吮、咬合、取食植物叶片和摄食种子,似乎在卡尼期得到了快速传播(Labandeira,2006;Wappler et al., 2015)。

5 CPE期间陆地生态系统演变与兰格利亚火山作用的因果联系

近年来,兰格利亚(Wrangellia)大火成岩省喷发被认为是CPE期间环境、气候和生物变化的主要驱动因素(e.g.,Dal Corso et al., 2020;Lu et al., 2021;Mazaheri-Johari et al., 2021;Zhao et al., 2022;Jin et al., 2023)(图1;图3;图5)。兰格利亚大火成岩省在晚三叠世卡尼期喷发于泛大洋东部的低纬度地区,随后在晚侏罗世至早白垩世期间出现增生,目前出露于北美西北部地区(Greene et al., 2010)(图1-a)。兰格利亚玄武岩层厚度通常在3.5~6 km之间,由于晚侏罗世至早白垩世增生过程中可能的俯冲作用,因此尚无法准确确定其原始喷发体积,但后来的地质填图工作表明兰格利亚大火成岩省在晚三叠世卡尼期至少有1×10⁶ km³的玄武岩被喷出(Greene et al., 2010)(图1-b)。然而,兰格利亚大火成岩省精确的同位素年龄目前并没有相关报道,其与CPE的关系仍存在不确定性(e.g.,Greene et al., 2010;Dal Corso et al., 2020)。尽管如此,现有的生物地层学证据(如菊石类的Tropites dilleri组合、牙形石和双壳类Halobia)显示,兰格利亚大火成岩省的大部分喷发期与CPE事件同步发生(e.g.,Dal Corso et al., 2020)(图1)。其次,来自深海、远海、浅海和陆地湖泊等不同环境中记录的CIEs、Hg富集和Hg/TOC峰值对应的接近于0的Δ¹⁹⁹Hg值的同步出现,表明CPE期间存在足够引起全球环境、气候和生物扰动的大型火山活动喷发,而兰格利亚大火成岩省是最佳的候选者(Dal Corso et al., 2012,2020;Lu et al., 2021;Zhao et al., 2022;Jin et al., 2023;Zhang et al., 2024a)(图1-b;图2;图3)。此外,其他指标,如锶同位素和锇同位素,也显示了晚三叠世卡尼期地幔值的变化,表明兰格利亚大火成岩省喷发与CPE期间环境-气候变化之间存在明显的相关性(Korte et al., 2003;Xu et al., 2014;Nozaki et al., 2019;Tomimatsu et al., 2021;Zhao et al., 2022)。

现有证据表明兰格利亚大火成岩省可能主要存在4个喷发脉冲,并释放出大量轻碳同位素来影响全球碳循环(e.g.,Dal Corso et al., 2020;Lu et al., 2021)。兰格利亚大火成岩省每次喷发均会通过直接作用向大气—海洋系统输入含大量轻碳同位素的CO₂,这会导致全球变暖和显著的碳循环波动(CIEs)(e.g.,Dal Corso et al., 2020;Lu et al., 2021)(图5)。正如CPE期间海洋和湖泊环境中观察到的那样,Hg/TOC和CIEs几乎同步出现,表明大量同位素轻碳反复注入大气—海洋系统中(Lu et al., 2021;Mazaheri-Johari et al., 2021;Zhao et al., 2022;Jin et al., 2023)。

然而,地球化学模型模拟的结果显示,兰格利亚大火成岩省释放的轻碳同位素总量不足以引起全球不同地区和不同沉积环境中观察到CIEs的偏移程度(Li et al., 2020),这意味着除了兰格利亚大火成岩省以外,还存在其他的因素对CPE期间的环境-气候施加了影响。羌塘盆地晚三叠世卡尼期海相沉积物中记录了轨道周期可能在一定程度放大了CPE期间的水文循环(Zhang et al., 2024b),但CPE事件与轨道周期之间的关系仍需进一步研究来证实。

来自特提斯洋西部和东部地区的氧同位素、化学风化指数以及基于生物地球化学盒子模型模拟的结果,提供了CPE期间全球气候变暖的证据(Hornung et al., 2007a; Trotter et al., 2015;Sun et al., 2016;Dal Corso et al., 2022;Zhang et al., 2024a)。更高的温度会促进大量水汽蒸发,从而增加大气中的水饱和度以及海洋和陆地之间的温差,这会引起大气环流和水文循环的增强,并促进地表径流和化学风化作用增强,最终将大量营养物质输入湖泊或者海洋(Rostási et al., 2011;Dal Corso et al., 2015;Branyi et al., 2019b;Pecorari et al., 2023;Zhang et al., 2024a)(图5)。上述显著改善的气候条件,不仅促进了陆地植物区系从旱生向湿生的显著变化及现代针叶类植物和鳄鱼、海龟、哺乳类动物、昆虫的辐射,也为恐龙多样化事件铺平了道路(e.g.,Dal Corso et al., 2020)。

陆地气候条件、植物类型变化和大规模淡水系统的发展,共同推动了晚三叠世卡尼期全球性聚煤作用的恢复和发展(图5)。在CPE期间,全球温暖湿润的气候条件可以促进盆地内湿生植物广泛发育、湖平面升高以及广泛的沼泽化(Dal Corso et al., 2020;Lu et al., 2021),这些变化对全球性聚煤具有推动作用,最终导致全球范围内厚煤层广泛沉积、有机碳埋藏量和埋藏速率显著增加(Retallack et al., 1996;Dal Corso et al., 2022;Zhang et al., 2023)(图5)。同时,在聚煤过程中,大气CO₂可以通过光合作用被陆地高等植物吸收并最终赋存在煤层内,进而降低全球大气CO₂浓度(Cleal and Thomas,2005;Shao et al., 2020),这在一定程度上抵消了温室气体排放的变暖效应,使CPE期间波动变化的气候条件逐渐趋于稳定,最终可能导致CPE事件终止(图5)。

6 结论

现有的证据表明,CPE期间全球陆地出现了地表温度升高、湿润气候条件盛行、多次碳循环负偏移、Hg富集异常和大陆化学风化作用增强、地表水系广泛扩张(包括三角洲和沼泽广泛发育以及湖平面升高)、湿生植物和淡水藻类丰度显著增加、全球聚煤作用重新出现,也伴随着许多现代生态系统关键种群(包括针叶类植物、昆虫、恐龙、鳄鱼、海龟和哺乳动物的多样化或起源)的多样化和起源。4次几乎同步出现的碳同位素负偏移与Hg富集异常(Hg/TOC峰值)和Hg同位素证据,提供了兰格利亚大火成岩省是CPE期间陆地环境、气候和生物条件显著变化驱动因素的直接证据。兰格利亚大火成岩省通过释放大量CO₂引起全球大气环流和水文循环的增强,造成陆地环境和气候条件的显著改善(从暖干向暖湿过渡),促进了陆地动、植物的广泛发育。陆地环境-气候条件和植物类型的显著变化增加了陆地有机碳的埋藏量,推动了全球性聚煤作用的重现。全球性聚煤作用的再现可能部分抵消了温室气体排放引起的温室效应,对CPE的终结和气候稳定具有重要作用。

参考文献

[1] 金鑫, 时志强, 王艳艳, 段雄, 程明. 2015. 晚三叠世中卡尼期极端气候事件: 研究进展及存在问题. 沉积学报, 33(1): 105-115.

[2] [Jin X, Shi Z Q, Wang Y Y, Duan X, Cheng M. 2015. Mid-Carnian(Late Triassic)extreme climate event: advances and unsolved problems. Acta Sedimentologica Sinica, 33(1): 105-115]

[3] 鲁静, 杨敏芳, 邵龙义, 陈恕聪, 李永红, 周凯, 王万青. 2016. 陆相盆地古气候变化与环境演化、聚煤作用. 煤炭学报, 41(7): 1788-1797.

[4] [Lu J, Yang M F, Shao L Y, Chen S C, Li Y H, Zhou K, Wang W Q. 2016. Paleoclimate change and sedimentary environment evolution,coal accumulation: a Middle Jurassic terrestrial. Journal of China Coal Society, 41(7): 1788-1797]

[5] 时志强, 欧莉华, 罗凤姿, 李云, 钱利军. 2009. 晚三叠世卡尼期黑色页岩事件在龙门山地区的沉积学和古生物学响应. 古地理学报, 11(4): 375-383.

[6] [Shi Z Q, Ou L H, Luo F Z, Li Y, Qian L J. 2009. Black shale event during the Late Triassic Carnian Age: implications from sedimentary and palaeontological records in Longmen Mountains region. Journal of Palaeogeography(Chinese Edition), 11(4): 375-383]

[7] 王艳艳, 张彪, 时志强, 伊海生. 2013. 川西北地区晚三叠世卡尼期洪水事件沉积的碳、氧同位素记录. 古地理学报, 14(3): 375-382.

[8] [Wang Y Y, Zhang B, Shi Z Q, Yi H S. 2013. Oxygen and carbon isotopic records of the Late Triassic Carnian pluvial event deposits in northwestern Sichuan Province. Journal of Palaeogeography(Chinese Edition), 14(3): 375-382]

[9] 张文, 李玉宏, 张乔, 陈高潮, 韩伟, 赵峰华. 2017. 鄂尔多斯盆地南部延长组时代划分及长7-3对印支Ⅰ幕的响应. 地球科学, 42(9): 1565-1577.

[10] [Zhang W, Li Y H, Zhang Q, Chen G C, Han W, Zhao F H. 2017. Chronostratigraphic division of Yanchang Formation in southern Ordos Basin and response of Chang 7³ to episode I of Indosinian Movement. Earth Science, 42(9): 1565-1577]

[11] 赵向东, 薛乃华, 彭俊刚, 张海春, 王博. 2024. 晚三叠世卡尼期湿润幕的陆相响应研究: 现状与展望. 第四纪研究, 44(5): 1127-1140.

[12] [Zhao X D, Xue N H, Peng J G, Zhang H C, Wang B. 2024. Terrestrial responses to the Carnian pluvial episode in the Late Triassic: research status and prospects. Quaternary Sciences, 44(5): 1127-1140]

[13] 周统顺, 周惠琴. 1983. 中国三叠纪陆相地层及植物群. 中国地质科学院院报, 5(1): 95-110.

[14] [Zhou T S, Zhou H Q. 1983. Triassic non-marine strata and flora of China. Bulletin of the Chinese Academy of Geological Sciences, 5(1): 95-110]

[15] Andrews S D, Decou A. 2019. The Triassic of traill Ø and geographical society ØEast Greenland: implications for North Atlantic palaeogeography. Geological Journal, 54(4): 2124-2144.

[16] Arche A, López-Gómez J. 2014. The Carnian Pluvial Event in western Europe: new data from Iberia and correlation with the western Neotethys and eastern North America-NW Africa regions. Earth-Science Reviews, 128(1): 196-231.

[17] Baranyi V, Miller C S, Ruffell A, Hounslow M W, Kürschner W M. 2019a. A continental record of the Carnian Pluvial Episode(CPE)from the Mercia Mudstone Group(UK): palynology and climatic implications. Journal of the Geological Society, 176(1): 149-166.

[18] Baranyi V, Rostási Á, Raucsik B, Kürschner W M. 2019b. Palynology and weathering proxies reveal climatic fluctuations during the Carnian Pluvial Episode(CPE)(Late Triassic)from marine successions in the Transdanubian Range(western Hungary). Global and Planetary Change, 177: 157-172.

[19] Benton M J. 1991. What really happened in the Late Triassic? Historical Biology, 5: 263-278.

[20] Benton M J, Bernardi M, Kinsella C. 2018. The Carnian Pluvial Episode and the origin of dinosaurs. Journal of the Geological Society, 175(6): 1019-1026.

[21] Bernardi M, Gianolla P, Petti F M, Mietto P, Benton M J. 2018. Dinosaur diversification linked with the Carnian Pluvial Episode. Nature Communications, 9(1): 1499.

[22] Chen P, Xian B Z, Li M J, Liang X W, Wu Q R, Zhang W M, Wang J H, Wang Z, Liu J P. 2021. A giant lacustrine flood-related turbidite system in the Triassic Ordos Basin,China: sedimentary processes and depositional architecture. Sedimentology, 68(7): 3279-3306.

[23] Cleal C J, Thomas B A. 2005. Palaeozoic tropical rainforests and their effect on global climates: is the past the key to the present? Geobiology, 3(1): 13-31.

[24] Coram R A, Radley J D. 2023. The Carnian Pluvial Episode: a damp squib for life on land? Proceedings of the Geologists’ Association, 134: 551-561.

[25] Dal Corso J, Mietto P, Newton R J, Pancost R D, Preto N, Roghi G, Wignall P B. 2012. Discovery of a major negative¹³C spike in the Carnian(Late Triassic)linked to the eruption of Wrangellia flood basalts. Geology, 40(1): 79-82.

[26] Dal Corso J, Gianolla P, Newton R J, Franceschi M, Roghi G, Caggiati M, Raucsik B, Budai T, Haas J, Preto N. 2015. Carbon isotope records reveal synchronicity between carbon cycle perturbation and the “Carnian Pluvial Event”in the Tethys realm(Late Triassic). Global and Planetary Change, 127: 79-90.

[27] Dal Corso J, Gianolla P, Rigo M, Franceschi M, Roghi G, Mietto P, Manfrin S, Raucsik B, Budai T, Jenkyns H C, Reymond C E, Caggiati M, Gattolin G, Breda A, Merico A, Preto N. 2018. Multiple negative carbon-isotope excursions during the Carnian Pluvial Episode(Late Triassic). Earth-Science Reviews, 185: 732-750.

[28] Dal Corso J, Bernardi M, Sun Y, Song H, Seyfullah L J, Preto N, Gianolla P, Ruffell A, Kustatscher E, Roghi G, Merico A, Hohn S, Schmidt A R, Marzoli A, Newton R J, Wignall P B, Benton M J. 2020. Extinction and dawn of the modern world in the Carnian(Late Triassic). Science Advances, 6(38): eaba0099.

[29] Dal Corso J, Mills B J W, Chu D L, Newton R J, Song H J. 2022. Background Earth system state amplified Carnian(Late Triassic)environmental changes. Earth and Planetary Science Letters, 578: 117321.

[30] Datta P M. 2005. Earliest mammal with transversely expanded upper molar from the Late Triassic(Carnian)Tiki Formation,South Rewa Gondwana Basin,India. Journal of Verterbrate Paleontology, 25(1): 200-207.

[31] Desojo J B, Heckert A B, Martz J W, Parker W G, Schoch R R, Small B J, Sulej T. 2013. Aetosauria:a clade of armoured pseudosuchians from the Upper Triassic continental beds. In: Nesbitt S J,Desojo J B,Irmis R B(eds).Anatomy,Phylogeny and Palaeobiology of Early Archosaurs and Their Kin. Geological Society,London,Special Publications, 379: 203-239.

[32] Desojo J B, Fiorelli L E, Ezcurra M D, Martinelli A G, Ramezani J, von Baczko M B, Trotteyn M J, Montefeltro F C, Ezpeleta M, Langer M C. 2020. The Late Triassic Ischigualasto Formation at Cerro Las Lajas(La Rioja,Argentina): fossil tetrapods,high-resolution chronostratigraphy,and faunal correlations. Scientific Reports, 10: 12782.

[33] DiMichele W A, Bashforth A R, Falcon-Lang H J, Lucas S G. 2020. Uplands,lowlands,and climate: taphonomic megabiases and the apparent rise of a xeromorphic,drought-tolerant flora during the Pennsylvanian-Permian transition. Palaeogeography,Palaeoclimatology,Palaeoecology, 559: 109965.

[34] Ezcurra M D, Fiorelli L E, Martinelli A G, Rocher S, von Baczko M B, Ezpeleta M, Taborda J R A, Hechenleitner E M, Trotteyn M J, Desojo J B. 2017. Deep faunistic turnovers preceded the rise of dinosaurs in southwestern Pangaea. Nature Ecology & Evolution, 1(10): 1477-1483.

[35] Fijałkowska-Mader A, Jewuła K, Bodor E. 2021. Record of the Carnian Pluvial Episode in the Polish microflora. Palaeoworld, 30(1): 106-125.

[36] Fu X G, Wang J, Wen H G, Wang Z W, Zeng S Q, Song C Y, Chen W B, Wan Y L. 2020. A possible link between the Carnian Pluvial Event,global carbon-cycle perturbation,and volcanism: new data from the Qinghai-Tibet Plateau. Global and Planetary Change, 194: 103300.

[37] Furin S, Preto N, Rigo M, Roghi G, Gianolla P, Crowley J L, Bowring S A. 2006. High-precision U-Pb zircon age from the Triassic of Italy: implications for the Triassic time scale and the Carnian origin of calcareous nannoplankton and dinosaurs. Geology, 34: 1009-1012.

[38] Gaffney E. 1990. The comparative osteology of the triassic turtle proganochelys. Bulletin of the American Museum of Natural History, 194: 1.

[39] Greene A R, Scoates J S, Weis D, Katvala E C, Israel S, Nixon G T. 2010. The architecture of oceanic plateaus revealed by the volcanic stratigraphy of the accreted Wrangellia oceanic plateau. Geosphere, 6(1): 47-73.

[40] Horn B L D, Goldberg K, Schultz C L. 2018. A loess deposit in the Late Triassic of southern Gondwana,and its significance to global paleoclimate. Journal of South American Earth Sciences, 81: 189-203.

[41] Hornung T, Brandner R. 2005. Biochronostratigraphy of the Reingraben turnover(Hallstatt Facies Belt): local black shale events controlled by regional tectonics,climatic change and plate tectonics. Facies, 51(1): 460-479.

[42] Hornung T, Brandner R, Krystyn L, Joachimski M M, Keim L. 2007a. Multistratigraphic constraints on the NW Tethyan “Carnian crisis”. New Mexico Museum of Natural History and Science Bulletin, 41: 59-67.

[43] Hornung T, Krystyn L, Brandner R. 2007b. A Tethys-wide mid-Carnian(Upper Triassic)carbonate productivity crisis: evidence for the Alpine Reingraben Event from Spiti(Indian Himalaya)? Journal of Asian Earth Sciences, 30(2): 285-302.

[44] Hounslow M W, Hu M Y, Mørk A, Vigran J O, Weitschat W, Orchard M J. 2007. Magneto-biostratigraphy of the Middle to Upper Triassic transition,central Spitsbergen,Arctic Norway. Journal of the Geological Society, 164(3): 581-597.

[45] Hsiou A S, Nydam R L, Simões T R, Pretto F A, Onary S, Martinelli A G, Liparini A, de Vivar Martínez P R R, Soares M B, Schultz C L, Caldwell M W. 2019. A new clevosaurid from the Triassic(Carnian)of Brazil and the rise of sphenodontians in Gondwana. Scientific Reports, 9: 11821.

[46] Jin X, Shi Z Q, Rigo M, Franceschi M, Preto N. 2018. Carbonate platform crisis in the Carnian(Late Triassic)of Hanwang(Sichuan Basin,South China): insights from conodonts and stable isotope data. Journal of Asian Earth Sciences, 164: 104-124.

[47] Jin X, Gianolla P, Shi Z Q, Franceschi M, Caggiati M, Du Y X, Preto N. 2020. Synchronized changes in shallow water carbonate production during the Carnian Pluvial Episode(Late Triassic)throughout Tethys. Global and Planetary Change, 184: 103035.

[48] Jin X, Baranyi V, Caggiati M, Franceschi M, Wall C J, Liu G L, Schmitz M D, Gianolla P, Ogg J G, Lu G, Shi Z Q, Preto N. 2021. Middle Triassic lake deepening in the Ordos Basin of North China linked with global sea-level rise. Global and Planetary Change, 207: 103670.

[49] Jin X, Tomimatsu Y, Yin R S, Onoue T, Franceschi M, Grasby S E, Du Y X, Rigo M. 2023. Climax in Wrangellia LIP activity coincident with major Middle Carnian(Late Triassic)climate and biotic changes: mercury isotope evidence from the Panthalassa pelagic domain. Earth and Planetary Science Letters, 607: 118075.

[50] Kammerer C F, Ordoñez M A. 2021. Dicynodonts(Therapsida: Anomodontia)of south America. Journal of South American Earth Sciences, 108: 103171.

[51] Kammerer C F, Fröbisch J, Angielczyk K D. 2013. On the validity and phylogenetic position of Eubrachiosaurus browni,a kannemeyeriiform dicynodont(Anomodontia)from Triassic North America. PLOS One, 8(5): e64203

[52] Kielan-Jaworowska Z, Cifelli R L, Luo Z X. 2016. Mammals from the Age of Dinosaurs. Berkeley: University of California Press.

[53] Klausen T G, Nyberg B, Helland-Hansen W. 2019. The largest delta plain in Earth’s history. Geology, 47(5): 470-474.

[54] Korte C, Kozur H W, Bruckschen P, Veizer J. 2003. Strontium isotope evolution of Late Permian and Triassic seawater. Geochimica et Cosmochimica Acta, 67(1): 47-62.

[55] Korte C, Jasper T, Kozur H W, Veizer J. 2005. δ¹⁸O and δ¹³C of Permian brachiopods: a record of seawater evolution and continental glaciation. Palaeogeography,Palaeoclimatology,Palaeoecology, 224(4): 333-351.

[56] Kozur H W, Bachmann G H. 2010. The Middle Carnian Wet Intermezzo of the Stuttgart Formation(Schilfsandstein),Germanic Basin. Palaeogeography,Palaeoclimatology,Palaeoecology, 290(1-4): 107-119.

[57] Kustatscher E, Ash S R, Karasev E, Pott C, Vajda V, Yu J X, McLoughlin S. 2018. Flora of the Late Triassic. In: The Late Triassic World. Cham: Springer International Publishing,545-622.

[58] Labandeira C C. 2000. The paleobiology of pollination and its precursors. The Paleontological Society Papers, 6: 233-270.

[59] Labandeira C C. 2006. The four phases of plant-arthropod associations in deep time. Geologica Acta, 4(4): 409-438.

[60] Langer M C, Ramezani J, 2018. U-Pb age constraints on dinosaur rise from south Brazil. Gondwana Research, 57: 133-140.

[61] Lestari W, Al-Suwaidi A, Fox C P, Vajda V, Hennhoefer D. 2024. Carbon cycle perturbations and environmental change of the middle Permian and Late Triassic Paleo-Antarctic circle. Scientific Reports, 14(1): 9742.

[62] Li C, Wu X C, Rieppel O, Wang L T, Zhao L J. 2008. An ancestral turtle from the Late Triassic of southwestern China. Nature, 456: 497-501.

[63] Li L Q, Kürschner W M, Lu N, Chen H Y, An P C, Wang Y D. 2022a. Palynological record of the Carnian Pluvial Episode from the northwestern Sichuan Basin,SW China. Review of Palaeobotany and Palynology, 304: 104704.

[64] Li Q, Ruhl M, Wang Y D, Xie X P, An P C, Xu Y Y. 2022b. Response of Carnian Pluvial Episode evidenced by organic carbon isotopic excursions from western Hubei,South China. Palaeoworld, 31(2): 324-333.

[65] Li Y, Yang R C. 2023. Astronomical calibration of a ten-million-year Triassic lacustrine record in the Ordos Basin,North China. Sedimentology, 70(2): 407-433.

[66] Li Z H, Chen Z Q, Zhang F F, Ogg J G, Zhao L S. 2020. Global carbon cycle perturbations triggered by volatile volcanism and ecosystem responses during the Carnian Pluvial Episode(Late Triassic). Earth-Science Reviews, 211: 103404.

[67] Lichtig A J, Lucas S G, Klein H, Lovelace D M. 2018. Triassic turtle tracks and the origin of turtles. Historical Biology, 30(8): 1112-1122.

[68] Lindström S, Erlström M, Piasecki S, Nielsen L H, Mathiesen A. 2017. Palynology and terrestrial ecosystem change of the Middle Triassic to lowermost Jurassic succession of the eastern Danish Basin. Review of Palaeobotany and Palynology, 244: 65-95.

[69] Liu J, Li L, Li X W. 2013. SHRIMP U-Pb zircon dating of the Triassic Ermaying and Tongchuan formations in Shanxi,China and its stratigraphic implications. Vertebrata Palasiatica, 51(2): 162-168.

[70] Liu J, Ramezani J, Li L, Shang Q H, Xu G H, Wang Y Y, Yang J S. 2018. High-precision temporal calibration of Middle Triassic vertebrate biostratigraphy: U-Pb zircon constraints for the Sinokannemeyeria Fauna and Yonghesuchus. Vertebrata Palasiatica, 56(1): 16-24.

[71] Lu G, Gou M X, Liu G L, Wang C C, Shi Z Q. 2022. Zircon U-Pb dating of tuff layers in the middle-upper Triassic strata of successions and sedimentation of Chang 7 member in the Ordos Basin,China. Frontiers in Earth Science, 10: 908940.

[72] Lu J, Zhang P X, Yang M F, Shao L Y, Hilton J. 2020. Continental records of organic carbon isotopic composition(δ¹³C_org),weathering,paleoclimate and wildfire linked to the End-Permian Mass Extinction. Chemical Geology, 558: 119764.

[73] Lu J, Zhang P X, Dal Corso J, Yang M F, Wignall P B, Greene S E, Shao L Y, Lyu D, Hilton J. 2021. Volcanically driven lacustrine ecosystem changes during the Carnian Pluvial Episode(Late Triassic). Proceedings of the National Academy of Sciences of the United States of America, 118(40): e2109895118.

[74] Lucas S G. 1993. Vertebrate biochronology of the Triassic of natural history. Science Bulletin, 3: 301-306.

[75] Mancuso A C, Benavente C A, Irmis R B, Mundil R. 2020. Evidence for the Carnian Pluvial Episode in Gondwana: new multiproxy climate records and their bearing on early dinosaur diversification. Gondwana Research, 86: 104-125.

[76] Mader N K, Redfern J, ElOuataoui M. 2017. Sedimentology of the Essaouira Basin(Meskala Field)in context of regional sediment distribution patterns during Upper Triassic pluvial events. Journal of African Earth Sciences, 130: 293-318.

[77] Marchetti L, Forte G, Kustatscher E, DiMichele W A, Lucas S G, Roghi G, Juncal M A, Hartkopf-Fröder C, Krainer K, Morelli C, Ronchi A. 2022. The Artinskian Warming Event: an Euramerican change in climate and the terrestrial biota during the early Permian. Earth-Science Reviews, 226: 103922.

[78] Martínez R N, Sereno P C, Alcober O A, Colombi C E, Renne P R, Montañez I P, Currie B S. 2011. A basal dinosaur from the dawn of the dinosaur era in southwestern Pangaea. Science, 331(6014): 206-210.

[79] Mazaheri-Johari M, Gianolla P, Mather T A, Frieling J, Chu D L, Dal Corso J. 2021. Mercury deposition in western Tethys during the Carnian Pluvial Episode(Late Triassic). Scientific Reports, 11(1): 17339.

[80] Mazaheri-Johari M, Roghi G, Caggiati M, Kustatscher E, Ghasemi-Nejad E, Zanchi A, Gianolla P. 2022. Disentangling climate signal from tectonic forcing: the Triassic Aghdarband Basin(Turan Domain,Iran). Palaeogeography,Palaeoclimatology,Palaeoecology, 586: 110777.

[81] Mietto P, Manfrin S, Preto N, Rigo M, Roghi G, Furin S, Gianolla P, Posenato R, Muttoni G, Nicora A, Buratti N, Cirilli S, Spötl C, Ramezani J, Bowring S A. 2012. The global boundary stratotype section and point(GSSP)of the Carnian Stage(Late Triassic)at Prati di Stuores/Stuores Wiesen Section(Southern Alps,NE Italy). Episodes, 35: 414-430.

[82] Miller C S, Peterse F, da Silva A C, Baranyi V, Reichart G J, Kürschner W M. 2017. Astronomical age constraints and extinction mechanisms of the Late Triassic Carnian crisis. Scientific Reports, 7(1): 2557.

[83] Mueller S, Krystyn L, Kürschner W M. 2016a. Climate variability during the Carnian Pluvial Phase: a quantitative palynological study of the Carnian sedimentary succession at Lunz am See,Northern Calcareous Alps,Austria. Palaeogeography,Palaeoclimatology,Palaeoecology, 441: 198-211.

[84] Mueller S, Hounslow M W, Kürschner W M. 2016b. Integrated stratigraphy and palaeoclimate history of the Carnian Pluvial event in the Boreal realm: new data from the Upper Triassic Kapp Toscana Group in central Spitsbergen(Norway). Journal of the Geological Society, 173(1): 186-202.

[85] Nicholson D B, Mayhew P J, Ross A J. 2015. Changes to the fossil record of insects through fifteen years of discovery. PLoS One, 10(7): e0128554.

[86] Nozaki T, Nikaido T, Onoue T, Takaya Y, Sato K, Kimura J I, Chang Q, Yamashita D, Sato H, Suzuki K, Kato Y, Matsuoka A. 2019. Triassic marine Os isotope record from a pelagic chert succession,Sakahogi section,Mino Belt,southwest Japan. Journal of Asian Earth Sciences: X,1: 100004.

[87] Olsen P E. 1997. Stratigraphic record of the early Mesozoic breakup of Pangea in the Laurasia-Gondwana rift system. Annual Review of Earth and Planetary Sciences, 25: 337-401.

[88] Olsen P E, Reid J C, Taylor K B, Whiteside J H, Kent D. 2015. Revised stratigraphy of Late Triassic age strata of the Dan River Basin(Virginia and North Carolina,USA)based on drill core and outcrop Data. Southeastern Geology, 51: 1-31.

[89] Pecorari M, Caggiati M, Dal Corso J, Cruciani G, Tateo F, Chu D L, Gianolla P. 2023. Weathering and sea level control on siliciclastic deposition during the Carnian Pluvial Episode(Southern Alps,Italy). Palaeogeography,Palaeoclimatology,Palaeoecology, 617: 111495.

[90] Peng J G, Slater S M, Vajda V. 2022. A Late Triassic vegetation record from the Huangshanjie Formation,Junggar Basin,China: possible evidence for the Carnian Pluvial Episode. Geological Society,London,Special Publications, 521(1): 95-108.

[91] Pott C, Krings M, Kerp H. 2008. The Carnian(Late Triassic)flora from Lunz in Lower Austria: paleoecological considerations. Palaeoworld, 17(3-4): 172-182.

[92] Racki G, Lucas S G. 2020. Timing of dicynodont extinction in light of an unusual Late Triassic Polish fauna and Cuvier’s approach to extinction. Historical Biology, 32: 452-461.

[93] Rahman N U, Xian B Z, Fang L H, Chen S R, Chen P, Ullah Z, Wang P Y. 2024. Volcanically driven terrestrial environmental perturbations during the Carnian Pluvial Episode in the eastern Tethys. Acta Geologica Sinica-English Edition, 98(3): 753-770.

[94] Retallack G J, Veevers J J, Morante R. 1996. Global coal gap between Permian-Triassic extinction and Middle Triassic recovery of peat-forming plants. Geological Society of America Bulletin, 108: 195-207.

[95] Rigo M, Trotter J A, Preto N, Williams I S. 2012. Oxygen isotopic evidence for Late Triassic monsoonal upwelling in the northwestern Tethys. Geology, 40: 515-518.

[96] Roghi G. 2004. Palynological investigations in the Carnian of the Cave del Predil area(Julian Alps,NE Italy). Review of Palaeobotany and Palynology, 132(1): 1-35.

[97] Roghi G, Gianolla P, Minarelli L, Pilati C, Preto N. 2010. Palynological correlation of Carnian humid pulses throughout western Tethys. Palaeogeography,Palaeoclimatology,Palaeoecology, 290(1-4): 89-106.

[98] Roghi G, Gianolla P, Kustatscher E, Schmidt A R, Seyfullah L J. 2022. An exceptionally preserved terrestrial record of LIP effects on plants in the Carnian(Upper Triassic)amber-bearing section of the Dolomites,Italy. Frontiers in Earth Science, 10: 900586.

[99] Rostási Á, Raucsik B, Varga A. 2011. Palaeoenvironmental controls on the clay mineralogy of Carnian sections from the Transdanubian Range(Hungary). Palaeogeography,Palaeoclimatology,Palaeoecology, 300(1-4): 101-112.

[100] Ruffell A, Simms M J, Wignall P B. 2016. The Carnian Humid Episode of the late Triassic: a review. Geological Magazine, 153(2): 271-284.

[101] Schoch R R. 2013. The evolution of major temnospondyl clades: an inclusive phylogenetic analysis. Journal of Systematic Palaeontology, 11: 673-705.

[102] Seyfullah L J, Beimforde C, Dal Corso J, Perrichot V, Rikkinen J, Schmidt A R. 2018. Production and preservation of resins: past and present. Biological Reviews of the Cambridge Philosophical Society, 93(3): 1684-1714.

[103] Shao L Y, Wang X T, Wang D D, Li M P, Wang S, Li Y J, Shao K, Zhang C, Gao C X, Dong D X, Cheng A G, Lu J, Ji C W, Gao D. 2020. Sequence stratigraphy,paleogeography,and coal accumulation regularity of major coal-accumulating periods in China. International Journal of Coal Science & Technology, 7(2): 240-262.

[104] Sidorchuk E A, Schmidt A R, Ragazzi E, Roghi G, Lindquist E E. 2015. Plant-feeding mite diversity in Triassic amber(Acari: Tetrapodili). Journal of Systematic Palaeontology, 13(2): 129-151.

[105] Simms M J, Ruffell A H. 1989. Synchroneity of climatic change and extinctions in the Late Triassic. Geology, 17(3): 265-268.

[106] Stocker M R, Nesbitt S J, Kligman B T, Paluh D J, Marsh A D, Blackburn D C, Parker W G. 2017. The earliest equatorial record of frogs from the Late Triassic of Arizona. Biology Letters, 15: 20180922.

[107] Sun Y D, Wignall P B, Joachimski M M, Bond D P G, Grasby S E, Lai X L, Wang L N, Zhang Z T, Sun S. 2016. Climate warming,euxinia and carbon isotope perturbations during the Carnian(Triassic)Crisis in South China. Earth and Planetary Science Letters, 444: 88-100.

[108] Sun Y D, Richoz S, Krystyn L, Zhang Z T, Joachimski M M. 2019. Perturbations in the carbon cycle during the Carnian Humid Episode: carbonate carbon isotope records from southwestern China and northern Oman. Journal of the Geological Society, 176(1): 167-177.

[109] Sun Y W, Li X, Liu Q Y, Zhang M D, Li P, Zhang R, Shi X. 2020. In search of the inland Carnian Pluvial Event: Middle-Upper Triassic transition profile and U-Pb isotopic dating in the Yanchang Formation in Ordos Basin,China. Geological Journal, 55(7): 4905-4919.

[110] Tomimatsu Y, Nozaki T, Sato H, Takaya Y, Kimura J I, Chang Q, Naraoka H, Rigo M, Onoue T. 2021. Marine osmium isotope record during the Carnian “Pluvial Episode”(Late Triassic)in the pelagic Panthalassa Ocean. Global and Planetary Change, 197: 103387.

[111] Trotter J A, Williams I S, Nicora A, Mazza M, Rigo M. 2015. Long-term cycles of Triassic climate change: a new δ¹⁸O record from conodont apatite. Earth and Planetary Science Letters, 415: 165-174.

[112] Tverdokhlebov V P, Tverdokhlebova G I, Surkov M V, Benton M J. 2003. Tetrapod localities from the Triassic of the SE of European Russia. Earth-Science Reviews, 60: 1-66.

[113] Wappler T, Kustatscher E, Dellantonio E. 2015. Plant-insect interactions from Middle Triassic(late Ladinian)of Monte Agnello(Dolomites,N-Italy): initial pattern and response to abiotic environmental perturbations. PeerJ, 3(7): e921.

[114] Xu G P, Hannah J L, Stein H J, Mørk A, Vigran J O, Bingen B, Schutt D L, Lundschien B A. 2014. Cause of Upper Triassic climate crisis revealed by Re-Os geochemistry of Boreal black shales. Palaeogeography,Palaeoclimatology,Palaeoecology, 395: 222-232.

[115] Zhang P X, Yang M F, Lu J, Jiang Z F, Zhou K, Xu X T, Wang Y, Wu L, Chen H J, Zhu X R, Guo Y H, Ye H J, Shao L Y, Hilton J. 2023. Floral response to the Late Triassic Carnian Pluvial Episode. Frontiers in Ecology and Evolution, 11: 1199121.

[116] Zhang P X, Yang M F, Lu J, Jiang Z F, Vervoort P, Zhou K, Xu X T, Chen H J, Wang Y, He Z, Bian X, Shao L Y, Hilton J. 2024a. Four volcanically driven climatic perturbations led to enhanced continental weathering during the Late Triassic Carnian Pluvial Episode. Earth and Planetary Science Letters, 626: 118517.

[117] Zhang P X, Yang M F, Lu J, Jiang Z F, Vervoort P, Zhou K, Xu X T, Chen H J, Wang Y, He Z, Bian X, Shao L Y, Hilton J. 2025. Terrestrial mercury anomalies across the Permian-Triassic transition in North China linked to volcanism. Chemical Geology, 673: 122555.

[118] Zhang Q, Fu X G, Wang J, Mansour A, Wei H Y, Zhang T, Wang M. 2024b. Orbitally-paced climate change during the Carnian Pluvial Episode. Earth and Planetary Science Letters, 626: 118546.

[119] Zhang Y, Li M S, Ogg J G, Montgomery P, Huang C J, Chen Z Q, Shi Z Q, Enos P, Lehrmann D J. 2015. Cycle-calibrated magnetostratigraphy of middle Carnian from South China: implications for Late Triassic time scale and termination of the Yangtze Platform. Palaeogeography,Palaeoclimatology,Palaeoecology, 436: 135-166.

[120] Zhao H, Grasby S E, Wang X D, Zhang L, Liu Y, Chen Z Q, Hu Z C, Huang Y G. 2022. Mercury enrichments during the Carnian Pluvial Event(Late Triassic)in South China. Geological Society of America Bulletin, 134(9-10): 2709-2720.

[121] Zhu R K, Cui J W, Deng S H, Luo Z, Lu Y Z, Qiu Z. 2019. High-precision dating and geological significance of Chang 7 tuff zircon of the Triassic Yanchang Formation,Ordos Basin in Central China. Acta Geologica Sinica-English Edition, 93(6): 1823-1834.

基金资助

*国家重点研发计划(2022YFF0800203/01)

国家自然科学基金项目(42472227)

国家自然科学基金项目(42402179)

河北省柳江盆地地质遗迹保护项目(Z1303002403442001)

河南省高等学校重点科研项目(24B410001)

河南城建学院科教融汇项目(KX2024022)

河南城建学院科教融汇项目(KX2024023)

河南城建学院大学生创新创业训练计划(202411765018)