横断山南段上新世的植被多样性与分布格局  

Vegetation diversity and distribution in the Pliocene of the southern Hengduan Mountains region

作　　者：黄永江[1] 苏涛[2] 朱海 贾林波 胡瑾瑾[1] 纪运恒[1] 周浙昆[1,2] Yongjiang Huang;Tao Su;Hai Zhu;Linbo Jia;Jinjin Hu;Yunheng Ji;Zhekun Zhou(Key Laboratory for Plant Biodiversity and Biogeography of East Asia,Kunming Institute of Botany,Chinese Academy of Sciences,Kunming 650201;Key Laboratory of Tropical Forest Ecology,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Mengla,Yunnan 666303;Collegeof Life Science,ShangraoNormal University,Shangrao,Jiangxi 334001;State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008)

机构地区：[1]中国科学院昆明植物研究所东亚植物多样性与生物地理学重点实验室,昆明650201 [2]中国科学院西双版纳热带植物园热带森林生态学重点实验室,云南勐腊66303 [3]上饶师范学院生命科学学院,江西上饶334001 [4]中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室,南京210008

出　　处：《生物多样性》2022年第11期56-69,共14页Biodiversity Science

基　　金：国家自然科学基金(31700184,41972023);中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室开放项目(183132);中国科学院“西部青年学者”人才项目;云南省“万人计划”青年拔尖人才项目(YNWR-QNBJ-2019-261)。

摘　　要：横断山南段复杂的地形地貌和多样的气候环境造就了高度丰富的植被多样性。这种植被多样性的演化与形成是植物学、生态学等领域共同关注的科学问题,而植物化石是回答这一科学问题的重要媒介。本文基于横断山南段的9个上新世化石植物群,根据其植物组成和优势成分,分析其所代表的植被类型,总结了该地区上新世的植被多样性与空间分布,并结合古环境研究资料,探讨该地区植被多样性的兴起,植被分布格局的形成,及其与环境变迁之间的关联。结果显示,横断山南段在上新世时期已经具有了多种植被类型,包括亚热带常绿阔叶林、亚热带落叶阔叶林、硬叶常绿阔叶林、针阔叶混交林、灌丛草地等,体现了丰富的植被多样性;植被类型从南面的偏热性植被向北面的偏温性植被逐渐转变,反映了当时随纬度变化的海拔梯度,植被类型与分布呈现出与现在高度相似的格局。同时,小范围内也具有适应于不同气候的植被类型,反映了当地较大的海拔落差,可能与高大山体的存在有着密切关联。我们推测,横断山南段现在丰富的植被多样性和随纬度变化的植被面貌最晚在上新世就已基本形成,但形成时间是否更早则需要更多、更老化石植物群的发现与研究。Aims:Due to complex geomorphology and diverse landscapes,the southern Hengduan Mountains region is home to highly diverse vegetation.The evolution and formation of such diversity is an interesting topic in the fields of botany and ecology,and plant fossils are an important proxy for researching this question.Method:In this study,we integrated published sources of nine fossil floras from the Pliocene of the southern Hengduan Mountains region.We first inferred the vegetation types of these fossil floras on the basis of their taxonomic compositions and dominant elements,and then depicted the diversity and spatial distribution of vegetation in the region during the Pliocene.We also correlated the rise of vegetation diversity and the formation of vegetation distribution to major environmental changes in the southern Hengduan Mountains region.Results:Our synthesis indicates that the southern Hengduan Mountain region already held a variety of vegetation types during the Pliocene,including subtropical evergreen broadleaved forest,subtropical deciduous broadleaved forest,sclerophyllous evergreen broadleaved forest,mixed coniferous broadleaved forest and shrubby meadow.The vegetation tended to have a warm affinity in the south and a cool-temperate affinity in the north,demonstrating altitudinal gradients with latitude at that time.Moreover,vegetation types are shown to be stratified at some localities,suggesting altitudinal gradients at local scales that are likely associated with the occurrence of high mountains.These are highly similar to the modern patterns of vegetation diversity and distribution in this region.Conclusion:Our study concludes that the modern diversity and distribution of vegetation in the southern Hengduan Mountain region was established no later than the Pliocene.However,more plant fossils from deeper times are needed to verify if the current vegetation was formed at an earlier geological age.

关 键 词：横断山 上新世 化石植物群 古植被 古海拔 

分 类 号：Q948.1[生物学—植物学]