【摘要】 海南岛长昌盆地始新世孢粉植物区系共计种子植物32科40属,蕨类植物8科11属。分析其中的种子植物区系成分并与海南岛现代植物区系进行对比,结果显示:(1)在科级水平,长昌盆地始新世孢粉植物区系以泛热带科占优势,为37.5%;热带—亚热带科占6.25%;而亚热带—温带科所占比例相对较高,达到31.25%。海南岛现代植物区系泛热带科高达48.07%,热带—亚热带科的比例也达到18.88%,而亚热带—温带科仅占15.88%。显然,长昌盆地始新世植物区系的组成亚热带性质较强。(2)在属级水平,长昌盆地始新世孢粉植物区系泛热带属占7.5%;热带—亚热带属占17.5%;而亚热带—温带属多达67.5%。海南岛现代植物区系泛热带属高达23.9%,热带—亚热带属更是高达57.5%,而亚热带—温带属仅占13.7%。对比表明,长昌盆地始新世植物区系明显以亚热带—温带性质为主,甚至出现了很多现今生活在较高海拔的山地植物,如冷杉(Abies)和铁杉(Tsuga)等。科属组成的分析表明,海南岛长昌盆地始新世的气温比现代要低,其周缘地带很可能分布有较高的山地。更多还原

【Abstract】 The Eocene palynoflora from Changchang basin of Hainan Island,China contains 40 genera of 32 families of spermatophyte pollen and 11 genera of 8 families of pteridophyte spore.Analysis of the seed plants of the Eocene palynoflora from the Changchang basin and comparison between the fossil and modern floras from Hainan Island show:(1)On family level,the Eocene palynoflora from Changchang basin is dominated by pantropic plants,count 37.5% of all numbers of families.Tropic-subtropic families only take 6.25%,and subtropic-temperate families count 31.25%.While,for the modern flora in Hainan Island,pantropic families count 48.07%,tropic-subtropic families are as high as 18.88%,and subtropic-temperate families count only 15.88%.Obviously,the Eocene palynoflora from Changchang Basin reveals much more subtropical characters.(2)On genus level,the Eocene palynoflora from Changchang basin consists of 7.5% of pantropic genera,17.5% of tropic-subtropic genera,and as high as 67.5% of subtropic-temperate genera.On the contrast,for the modern flora in Hainan Island,pantropic and tropic-subtropic genera increase substantially,up to 23.9% and 57.5% respectively;subtropic-temperate genera decrease greatly,only 13.7%.Thus,the Eocene palynoflora from Changchang basin is obviously characterized by subtropic-temperate plants,and even some alpine plants,such as Abies and Tsuga,etc.The Eocene temperature in Hainan Island is lower than today according to the composition of plant families and genera,and there might exist high-altitude mountains surrounding the Changchang basin.更多还原