Microstructure Of Three Angiosperms From Miocene In Eastern Zhejiang And Reconstruction Of Palaeoclimate

As a whole,the global temperature was in a variational state of dropping persistently in the Cenozoic.When studying the palaeoclimate,a medium that contains the information of the palaeoclimate has to be depended on.And plants which can change their bodies while the climate changes,just are the best indicators of climate change.In recent years,more and more people focused on the methods of the palaeoclimate reconstructed by fossil plants,and "Climate analysis of endemic species" is one of those methods for reconstructing palaeoclimate by endemic species, engendered in their evolutional process.Three fossil angiosperm leaves from the Miocene Xia'nanshan Formation of Tiantai in Zhejiang Province were studied in the present paper,and they are Betula mioluminifera Hu et Chaney,Zelkova ungeri kovats and Ilex cf.championii.By studying detailedly the leaf architecture and cuticular structure of these fossils,a fact was proved that the living plants Betula luminifera H.Winkl.,Zelkova schneideriana Hand.-Mazz.and Ilex championii Loes.are the nearest living relative species or similar species of the three fossil plants respectively,and the three living plants are also endemic species in China.The fossil records shows that the distribution areas of Betula luminifera H. Winkl.,Zelkova schneideriana Hand.-Mazz.and llex championii Loes.moved towards Southern China relative to their fossil species,and it proves that the climate in Eastern Zhejiang Province has been gradually becoming cooler since the Neogene. The palaeoclimate was reconstructed quantitatively by "Climate analysis of endemic species" method making use of the climate parameter in the distribution area of three living plants.The mean annual temperature that three fossil plants could live together was 12.5～20.8℃,and the mean annual rainfall was 1083.0～1695.4mm.The research shows that the Miocene climate was warm and humid in Tiantai,Zhejiang Province.