DOI: 10.1038/ngeo1984
论文题名: The role of fire in Miocene to Pliocene C 4 grassland and ecosystem evolution
作者: Hoetzel S. ; Dupont L. ; Schefuß E. ; Rommerskirchen F. ; Wefer G.
刊名: Nature Geoscience
ISSN: 17520894
出版年: 2013
卷: 6, 期: 12 起始页码: 1027
结束页码: 1030
语种: 英语
Scopus关键词: adaptation
; aridification
; aridity
; C4 plant
; carbon dioxide
; disturbance
; feedback mechanism
; fire behavior
; grass
; marine sediment
; Miocene
; paleoecology
; palynology
; photosynthesis
; Pliocene
; rainfall
; savanna
; seasonality
; sediment core
; wax
; Africa
; Poaceae
英文摘要: Modern savannah grasslands were established during the late Miocene and Pliocene (8-3 million years ago). In the tropics, grasslands are dominated by grasses that use the C 4 photosynthetic pathway, rather than the C 3 pathway. The C 4 pathway is better adapted to warm, dry and low-CO 2 conditions, leading to suggestions that declining atmospheric CO 2 levels, increasing aridity and enhanced rainfall seasonality allowed grasses using this pathway to expand during this interval. The role of fire in C 4 expansion may have been underestimated. Here we use analyses of pollen, microscopic charcoal and the stable isotopic composition of plant waxes from a marine sediment core off the coast of Namibia to reconstruct the relative timing of changes in plant composition and fire activity for the late Miocene and Pliocene. We find that in southwestern Africa, the expansion of C 4 grasses occurred alongside increasing aridity and enhanced fire activity. During further aridification in the Pliocene, the proportion of C 4 grasses in the grasslands increased, while the grassland contracted and deserts and semi-deserts expanded. Our results are consistent with the hypothesis that ecological disturbance by fire was an essential feedback mechanism leading to the establishment of C 4 grasslands in the Miocene and Pliocene. © 2013 Macmillan Publishers Limited. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/106638
Appears in Collections: 气候减缓与适应 科学计划与规划
There are no files associated with this item.
作者单位: MARUM - Center for Marine Environmental Sciences, University of Bremen, D-28359 Bremen, Germany
Recommended Citation:
Hoetzel S.,Dupont L.,Schefuß E.,et al. The role of fire in Miocene to Pliocene C 4 grassland and ecosystem evolution[J]. Nature Geoscience,2013-01-01,6(12)