云南羊邑地区晚上新世植被演替及其古气候意义

徐景先  Stephen Blackmore  王宇飞  李承森

    摘 要  云南羊邑晚上新世孢粉植物群含52个孢粉类型，其中被子植物占61.5%，裸子植物占9.6%，蕨类植物占25.0%，藻类植物占3.9%。根据各植物类群孢粉含量在整个剖面上的变化情况，将羊邑地层剖面划分为四个花粉带，分别讨论了四个花粉带时期的植被特征。羊邑晚上新世植物群数据表明，羊邑地区分布有山地常绿阔叶针叶混交林，距沉积地较远的山地分布有针叶林；古植被数据表明在羊邑地区晚上新世时期的气候为山地亚热带的气候特征。

LATE PLIOCENE VEGETATION AND CLIMATE OF YANGYI REGION, YUNNAN OF CHINA, RECONSTRUCTED FROM PALYNOLOGICAL DATA.

Jingxian Xu       Stephen Blackmore

Yufei Wang      Chengsen Li

    Abstract  The Late Pliocene palynoflora of Yangyi consists of fifty-two palynomorphs, comprising angiosperms (61.5%), gymnosperms (9.6%), ferns (25.0%) and algae (3.9%). According to the palynological data, four pollen zones are recognized through the stratigraphical sequence.
    The floristic components in the four pollen zones indicate the changes of vegetation and environment in Yangyi area during Late Pliocene: the vegetation type during pollen zone 1 was montane broad-leaved and coniferous forests under cool and humid condition; The pollen zone 2 montane broad-leaved and coniferous forests under warm and humid condition; the pollen zone 3 montane broad-leaved and coniferous forests with more broad-leaved deciduous trees than the pollen zone 2; the pollen zone 4 evergreen coniferous forests with high atmospheric humidity and low temperature.
    Evergreen coniferous forests were distributed on the slopes or high lands far from the deposit site through the period of deposition. Palaeovegetation suggested that montane subtropical climate dominated in the Yangyi area during Late Pliocene. A warming trend could represent from the pollen zone 1 to 2, while a cooling trend from the pollen zone 3 to 4. A humidity-decrease phase might occur at the end of the pollen zone 2.

    Key words  Late Pliocene, vegetation, climate, palynology, Yunnan.

Palaeontographica Abt. B. 2004，269：131-148