A new pollen record of the last 2.8 Ma from the Co Ngoin,central Tibetan Plateau

来源 :Science in China(Series D:Earth Sciences) | 被引量 : 0次 | 上传用户:chenyun120
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A new pollen record from the lake of Co Ngoin in the central Tibetan Plateau provides information on the vegetation and climate changes during the last 2.8 Ma. Seven major significant changes in pollen associations indicate the processes of vegetation change and possible tectonic uplifts. The seven changes in vegetation succession include a temperate montane conifer and broad-leaved mixed forest, cold temperate montane dark conifer forest, alpine shrub-meadow and alpine desert, montane dark coniferous forest and alpine shrub meadow, montane dark coniferous forest and alpine shrub meadow, montane dark coniferous forest and alpine meadow, and alpine desert and meadow. The pollen record provides the evidence of at least five times tectonic uplifts occurring at about 2.58 Ma, 1.87 Ma, 1.17 Ma, 0.83 Ma, and 0.3 Ma ago, respectively. Before 0.8 Ma, this region maintained the altitude below 4000 m a.s.l. Larger amplitude of uplift occurring at about 0.8 Ma ago enforced the plateau rising into cryosphere, shapin A new pollen record from the lake of Co Ngoin in the central Tibetan Plateau provides information on the vegetation and climate changes during the last 2.8 Ma. Seven major significant changes in pollen associations indicate the processes of vegetation change and possible tectonic uplifts. The seven changes in vegetation succession include a temperate montane conifer and broad-leaved mixed forest, cold temperate montane dark conifer forest, alpine shrub-meadow and alpine desert, montane dark coniferous forest and alpine shrub meadow, montane dark coniferous forest and alpine shrub meadow, montane dark The pollen record provides the evidence of at least five times tectonic uplifts occurring at about 2.58 Ma, 1.87 Ma, 1.17 Ma, 0.83 Ma, and 0.3 Ma ago, respectively. Before 0.8 Ma , this region maintained the altitude below 4000 m asl Larger amplitude of uplift occurring at about 0.8 Ma ago enforced the plateau rising into cryosphere, shapin
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