南极乔治王岛始新世化石山植物群及古气候的进一步研究

Antarctica plays an essential role in the global system. The study of palaeovegetation and palaeoclimate of Antarctica in geological time, however, is lagged due to the scarcity of plant fossils from this region. The present project plans to study continuously the early-middle Eocene Fossil Hill flora from the Fildes Peninsula of King George Island, Antarctica on the basis of previous research. We will work on the unstudied materials from Fossil Hill flora deposited in the Nanjing Institute of Geology and Palaeontology, CAS, and with special emphasis on the Podocarpaceous leafy shoots with cuticle preserved to learn the phylogenetic, evolutionary and phytogeographic history of this family. The Eocene vegetation in King George Island will be reconstructed comprehensively on the basis of our studies and related previous works. This flora will be compared with other contemporary floras to shed light on the palaeogeographic history of the Antarctica and the break-up of Gondwana. Meanwhile, we will reconstruct the early-middle Eocene climate based on plant fossils using multi-methods, including the nearest living relative method, the co-existence approach, the leaf margin analysis, and the Climate-Leaf Analysis Multivariate Program. The present study will contribute to our understanding of the evolution, radiation and dispersal of related Southern Hemisphere plant taxa, and the interaction of the break-up of Gondwana with global climate in geological time.

南极在全球系统中地位至关重要。然而，囿于化石材料的匮乏，对南极古植被和古气候的研究工作较少。本项目基于现保存于中国科学院南京地质古生物研究所的南极乔治王岛菲尔德斯半岛早-中始新世化石山植物群植物化石，拟在以往研究基础上，进一步系统研究植物群中尚未鉴定的化石，从而全面重建古植被面貌。对植物群中保存有角质层的罗汉松科化石重点研究，探讨其系统发育、演化和植物地理历史等科学问题。通过植物群深入对比研究，揭示南极洲古地理演化及冈瓦纳古陆的裂解过程等科学问题。在全面重建古植被的基础上，运用最近现生亲缘种法、共存分析法、叶缘分析法和气候- - 叶片分析多变量程序，定量重建南极洲乔治王岛地区始新世早-中期的古气候。这项研究对我们认识南半球相关植物类群的演化、辐射和扩散，以及冈瓦纳古陆裂解对全球气候演化的影响具有重要意义，它将为提高我国南极科学研究水平做出应有的贡献。