二叠纪-三叠纪转折期升温事件与陆地生态系统  

GLOBAL WARMING EVENT AND THE CHANGEOVER OF TERRESTRIAL ECOSYSTEMS DURING THE PERMIAN-TRIASSIC TRANSITION

作　　者：张华[1] 蔡垚峰 角升林 沈树忠 ZHANG Hua;CAI Yaofeng;JIAO Shenglin;SHEN Shuzhong(Key Laboratory of Palaeobiology and Petroleum Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,Jiangsu;University of Chinese Academy of Sciences,Beijing 100049;State Key Laboratory for Mineral Deposits Research,School of Earth Sciences and Engineering,and Frontiers Science Center for Critical Earth Material Cycling,Nanjing University,Nanjing 210023,Jiangsu)

机构地区：[1]中国科学院南京地质古生物研究所,古生物学与油气地层应用重点实验室,江苏南京210008 [2]中国科学院大学,北京100049 [3]南京大学地球科学与工程学院,关键地球物质循环前沿科学中心,内生金属成矿机制研究国家重点实验室,江苏南京210023

出　　处：《第四纪研究》2024年第5期1093-1107,共15页Quaternary Sciences

基　　金：国家自然科学基金重大项目(批准号:42293280);江苏省重大科技开放合作平台建设项目(批准号:BZ2023068)共同资助。

摘　　要：距今2.52亿年前的二叠纪末期,剧烈的火山活动导致大量CO_(2)和CH_(4)等温室气体释放,引起全球海洋表层平均水温快速上升8~10℃,而陆地的升温幅度可能更大。这次升温事件对海、陆生态系统都造成致命打击,然而,陆地生态系统对这次全球升温事件的响应模式研究相对较弱。全球二叠纪-三叠纪转折期陆相沉积序列中保存了诸多升温事件的证据,其中包括:全球不同地理区域的陆地植物群遭受了灾难性灭绝,北半球中-高纬度安加拉植物区裸子植物为主的植物群、低纬度地区华夏植物区的热带雨林型大羽羊齿植物群、南半球中-高纬度冈瓦纳植物群的舌羊齿类等高大树木都在二叠纪末消失,三叠纪初的植物化石以矮小的适应干旱环境的石松类为主;二叠纪末期全球范围内陆相地层中炭屑化石和燃烧源多环芳烃富集,表明二叠纪末的野火事件在全球范围内频繁发生,导致陆地生态系统的快速去森林化和早三叠世全球范围内煤沉积间断;二叠系乐平统灰绿色/黄绿色含煤岩系被下三叠统紫红色岩系覆盖,其中含有大量没有任何分选和磨圆的同生土壤角砾,以及蒸发环境下形成的淡水钙质结核和石膏沉积等,指示当时气候干旱和土壤系统崩溃。陆地植被系统的崩溃加剧了全球碳循环的异常波动和大陆风化,大量陆源物质输入海洋环境使其富营养化和缺氧面积急剧扩张、微生物岩和白云岩发育。二叠纪末整个地球地表生态环境灾变过程为当前地球所面临的快速升温提供了重要历史借鉴。At the end of the Permian,ca.252million years ago,intense volcanic activities released a massive amount of CO_(2),CH_(4) and other greenhouse gases,resulting the surface seawater temperature rapid rising by 8~10℃,and the temperature rise may be greater in the terrestrial ecosystem.This global warming event had a devastating impact on both Marine and terrestrial ecosystems.However,the pattern of response of terrestrial ecosystems to this global warming event has been relatively poorly studied.Evidence of this warming event is preserved in the terrestrial Permian-Triassic transitional sedimentary sequence,including:terrestrial floras suffered a worldwide catastrophic die off of many plant groups in different geographical zones and followed by an Early-Middle Triassic'coal gap';the Permian gymnosperm-dominated floras in the Angara flora realm in the middle and high paleolatitudes of the Northern Hemisphere,the tropical rainforest-type Gigantopteris flora in the Cathaysia flora realm in the low paleolatitudes,and the coal-forming Glossopteris flora in the Gondwana flora realm in the middle and high paleolatitudes of the southern hemisphere all experienced catastrophic losses at the end of the Permian,and replaced by the flora dominated by dwarf Lycopodium at the beginning of the Triassic,which is adapted to the drought environment.The enrichment of charcoal fossils and polycyclic aromatic hydrocarbons from combustion sources in the latest Permian terrestrial strata suggests that the wildfire events occurred frequently on a global scale,resulting in rapid deforestation of terrestrial ecosystems during the Permian-Triassic transition period and global'coal-gap'in the Early Triassic.The Lopingian(Upper Permian)gray-green/yellow-green coal-bearing sediments is covered by the Lower Triassic purplish-red sediments,which contains numerous syngenetic soil breccia without any sorting and grinding,as well as freshwater calcareous nodules and gypsum deposited in evaporative environments,indicating arid climatic conditions and

关 键 词：二叠纪-三叠纪转折期 升温事件 沉积记录 野火事件 陆地生态系统 

分 类 号：P534.46[天文地球—古生物学与地层学] P532[天文地球—地质学] P539.2P914.5