Key Laboratory of Economic Stratigraphy and Palaeogeography, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Sci Rep. 2016 Dec 23;6:39694. doi: 10.1038/srep39694.
Microbial carbonates commonly flourished following mass extinction events. The end-Devonian (Hangenberg) mass extinction event is a first-order mass extinction on the scale of the 'Big Five' extinctions. However, to date, it is still unclear whether global microbial carbonate proliferation occurred after the Hangenberg event. The earliest known Carboniferous stromatolites on tidal flats are described from intertidal environments of the lowermost Tournaisian (Qianheishan Formation) in northwestern China. With other early Tournaisian microbe-dominated bioconstructions extensively distributed on shelves, the Qianheishan stromatolites support microbial carbonate proliferation after the Hangenberg extinction. Additional support comes from quantitative analysis of the abundance of microbe-dominated bioconstructions through the Famennian and early Tournaisian, which shows that they were globally distributed (between 40° latitude on both sides of the palaeoequator) and that their abundance increased distinctly in the early Tournaisian compared to the latest Devonian (Strunian). Comparison of variations in the relative abundance of skeleton- versus microbe-dominated bioconstructions across the Hangenberg and 'Big Five' extinctions suggests that changes in abundance of skeletal bioconstructors may play a first-order control on microbial carbonate proliferation during extinction transitions but that microbial proliferation is not a general necessary feature after mass extinctions.
微生物碳酸盐通常在大规模灭绝事件后大量繁盛。晚泥盆世（汉根伯格）大灭绝事件是“五大灭绝”规模的一级灭绝事件。然而，迄今为止，汉根伯格事件后是否发生了全球微生物碳酸盐的增殖仍不清楚。最早的已知石炭纪潮坪层叠层石是在中国西北部下石炭统（前河山组）潮间带环境中描述的。随着其他早石炭世以微生物为主的生物构造广泛分布在陆架上，前河山叠层石支持汉根伯格灭绝后微生物碳酸盐的增殖。定量分析整个法门阶和早石炭世以微生物为主的生物构造的丰度也提供了额外的支持，结果表明它们在全球范围内分布（在古赤道两侧的 40°纬度之间），并且与晚泥盆世（斯特伦阶）相比，在早石炭世明显增加。通过比较汉根伯格灭绝和“五大灭绝”期间骨架生物构造与微生物生物构造相对丰度的变化表明，骨架生物构造丰度的变化可能对灭绝过渡期间微生物碳酸盐的增殖起着一级控制作用，但微生物的增殖并不是大灭绝后普遍需要的特征。
