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为了建立早-中三叠世双壳类的残存-复苏模式及深入探讨双壳类迟缓复苏的原因,对全球范围内该时期双壳类属的时限分布进行了统计.总体来看,3个亚纲(Pteriomorphia、Palaeotaxodont和Heteroconchia亚纲)和5种生活方式(外栖活动类、外栖固着类、半内栖类、内栖浅掘穴类和内栖深掘穴类)的双壳类均展示出了一致的规律,属级分异度直到中三叠世Anisian期才恢复到晚二叠世末生物大灭绝之前的水平.二叠纪残存类型在早-中三叠世双壳类中所占的比例逐步降低,从占过渡层的77.3%降低到了中三叠世Anisian期的33.7%,指示双壳类的缓慢复苏过程.而在整个早三叠世的漫长复苏期中,双壳类仅遭受背景灭绝,表明双壳类的迟缓复苏受限于长时期的高压环境,随着海洋环境的逐步好转,才逐渐出现新的类型.
In order to establish the remnant-recovery model of early-middle Triassic bivalves and investigate the reasons for the slow recovery of bivalves, the time-bound distribution of bivalves in this period was statistically analyzed. Overall, 3 (Pteriomorphia, Palaeotaxodont and Heteroconchia subclasses), and bivalves of the five lifestyles (zooplanktons, habitats, semi-inner benthic, boreal burrows and periglacials) All showed a consistent law, and the genus-level diversity did not reach the level of the pre-extinction period of the Late Permian until the Middle Triassic Anisian period.The Permian remnant types are similar in the Early-Middle Triassic Bivalve Gradually decreased from 77.3% of the transitional level to 33.7% of the Middle Triassic Anisian period, indicating a slow recovery process of bivalves, whereas during the long recovery period of the early Triassic, the double-shelled The genus was only extinct from the background, indicating that the slow recovery of bivalves is limited by the long-term high-pressure environment, and new types gradually emerge as the marine environment gradually improves.