Tree endurance on the Tibetan Plateau marks the world's highest known tree line of the Last Glacial Maximum

Because of heterogeneous topographies, high-mountain areas could harbor a significant pool of cryptic forest refugia (glacial microrefugia unrecognized by palaeodata), which, as a result of poor accessibility, have been largely overlooked. The juniper forests of the southern Tibetan Plateau, with on...

Full description

Saved in:
Bibliographic Details
Published in:The New phytologist 2010-01, Vol.185 (1), p.332-342
Main Authors: Opgenoorth, Lars, Vendramin, Giovanni G., Mao, Kangshan, Miehe, Georg, Miehe, Sabine, Liepelt, Sascha, Liu, Jianquan, Ziegenhagen, Birgit
Format: Article
Language:English
Subjects:
Adaptation, Physiological - genetics
Base Sequence
Chloroplasts
Chloroplasts - genetics
Demography
Ecological genetics
Ecosystem
Evolutionary genetics
Genetic diversity
Geography
glacial refugia
Haplotypes
high-mountain areas
Ice Cover
Juniperus - genetics
Juniperus - physiology
Juniperus tibetica complex
Molecular genetics
orographic leading edge
orographic rear edge
Polymorphism, Genetic
Population genetics
Refuge habitats
Tibet
Tibetan Plateau
Trees - physiology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Because of heterogeneous topographies, high-mountain areas could harbor a significant pool of cryptic forest refugia (glacial microrefugia unrecognized by palaeodata), which, as a result of poor accessibility, have been largely overlooked. The juniper forests of the southern Tibetan Plateau, with one of the highest tree lines worldwide, are ideal for assessing the potential of high-mountain areas to harbor glacial refugia. Genetic evidence for Last Glacial Maximum (LGM) endurance of these microrefugia is presented using paternally inherited chloroplast markers. Five-hundred and ninety individuals from 102 populations of the Juniperus tibetica complex were sequenced at three polymorphic chloroplast regions. Significant interpopulation differentiation and phylogeographic structure were detected (GST = 0.49, NST = 0.72, NST > GST, P < 0.01), indicating limited among-population gene flow. Of 62 haplotypes recovered, 40 were restricted to single populations. These private haplotypes and overall degrees of diversity were evenly spread among plateau and edge populations, strongly supporting the existence of LGM microrefugia throughout the present distribution range, partly well above 3500 m. These results mark the highest LGM tree lines known, illustrating the potential significance of high-mountain areas for glacial refugia. Furthermore, as the close vicinity of orographic rear-edge and leading-edge populations potentially allows gene flow, surviving populations could preserve the complete spectrum of rear-edge and leading-edge adaptations.
ISSN:0028-646X
1469-8137
DOI:10.1111/j.1469-8137.2009.03007.x