DOI: 10.1111/gcb.14150
Scopus记录号: 2-s2.0-85048239089
论文题名: Waxing and waning of forests: Late Quaternary biogeography of southeast Africa
作者: Ivory S.J. ; Lézine A.-M. ; Vincens A. ; Cohen A.S.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2018
卷: 24, 期: 7 起始页码: 2939
结束页码: 2951
语种: 英语
英文关键词: Africa
; biogeography
; global change
; hydrology
; Lake Malawi
; palaeoclimate
; palaeoenvironments
; tropical forests
Scopus关键词: biogeography
; climate change
; forest ecosystem
; global change
; hydrology
; montane forest
; paleoclimate
; paleoenvironment
; Quaternary
; tropical forest
; vegetation structure
; East African Lakes
; Lake Malawi
英文摘要: African ecosystems are at great risk. Despite their ecological and economic importance, long-standing ideas about African forest ecology and biogeography, such as the timing of changes in forest extent and the importance of disturbance, have been unable to be tested due to a lack of sufficiently long records. Here, we present the longest continuous terrestrial record of late Quaternary vegetation from southern Africa collected to date from a drill core from Lake Malawi covering the last ~600,000 years. Pollen analysis permits us to investigate changes in vegetation structure and composition over multiple climatic transitions. We observe nine phases of forest expansion and collapse related to regional hydroclimate change. The development of desert, steppe and grassland vegetation during arid periods is likely dynamically linked to thresholds in regional hydrology associated with lake level and moisture recycling. Species composition of these dryland ecosystems varied greatly and is unlike the vegetation found at Malawi today, with assemblages suggesting strong Somali-Masai affinities. Furthermore, nearly all semiarid assemblages contain low forest taxa abundances, suggesting that moist lowland gallery forests formed refugia along waterways during arid times. When the region was wet, forests were species-rich and very high afromontane tree abundances suggest frequent widespread lowland colonization by modern high elevation trees. Furthermore, species composition varied little amongst forest phases until ~80 ka when disturbance tolerant tree taxa characteristic of the modern vegetation increased in abundance. The waxing and waning of forests has important implications for understanding the processes that control modern tropical vegetation biogeography as well as the environments of early humans across Africa. Finally, this work highlights the resilience of montane forests during previous warm intervals, which is relevant for future climate change; however, we point to a fundamental shift in disturbance regimes which are crucial for the structure and composition of modern East African landscapes. © 2018 John Wiley & Sons Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/110351
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Department of Anthropology, Ohio State University, Columbus, OH, United States; Department of Geosciences, Penn State University, State CollegePA, United States; LOCEAN, CNRS, Paris, France; CEREGE, CNRS, Aix-en-Provence, France; Department of Geosciences, University of Arizona, Tucson, AZ, United States
Recommended Citation:
Ivory S.J.,Lézine A.-M.,Vincens A.,et al. Waxing and waning of forests: Late Quaternary biogeography of southeast Africa[J]. Global Change Biology,2018-01-01,24(7)