Mobile carbon supply in trees and shrubs at the alpine treeline ecotone

	Mobile carbon supply in trees and shrubs at the alpine treeline ecotone
	Wang, Qing-Wei; Liu, Cheng-Gang; Zhou, Wangming; Qi, Lin; Zhou, Li; Yu, Dapao; Dai, Limin
刊名	PLANT ECOLOGY
	2018
卷号	219 期号:4 页码:467-479
关键词	Growth Limitation Carbon Balance Microenvironments Stature Deciduous Treeline Species Functional Difference
ISSN号	1385-0237
英文摘要	Although the growth limitation hypothesis (GLH) is the most accepted physiological explanation for alpine treeline formation, the debate about its formation mechanisms still remains controversial due to contradictory findings from different studies. The functional difference between trees and alpine low-stature shrubs may hold answers, as shrubs grow well at higher elevations. We investigated carbon (C) storage in deciduous treeline species Betula ermanii (Erman's birch) and two dominant shrubs (deciduous Vaccinium uliginosum and evergreen Rhododendron aureum), which naturally grow next to each other at the treeline ecotone on Changbai Mountain, Northeast China. We determined growth and non-structural carbohydrate (NSC) concentrations in organs with increasing elevation at the mid-growing season. Results showed that in the treeline ecotone soil temperature was lower than tree canopy air temperature due to unobvious aerodynamic decoupling near the ground. Species growth consistently decreased with increasing elevation, while NSC concentrations responded differently to elevation between trees and shrubs. An elevational increase and decrease in NSC were observed in leaves and woody organs, respectively, of B. ermanii. NSC concentrations in each organ significantly increased with increasing elevation for R. aureum but decreased for V. uliginosum. At the treeline, shrubs had higher values than B. ermanii in NSC, ratios of soluble sugars to starch in leaves, and leaf mass per area. Organ dependence of NSC with increasing elevation in Betula trees provided partial support for the GLH, while R. aureum and V. uliginosum provided strong support for the GLH and carbon limitation hypothesis, respectively. These imply that alpine shrubs may have evolved to maintain more advantageous C balance and functional features than did trees as an adaptation to higher-elevation climates.
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公开日期	2018-04-10
内容类型	期刊论文
源URL	[http://ir.xtbg.org.cn/handle/353005/10808]
专题	西双版纳热带植物园_其他
推荐引用方式 GB/T 7714	Wang, Qing-Wei,Liu, Cheng-Gang,Zhou, Wangming,et al. Mobile carbon supply in trees and shrubs at the alpine treeline ecotone[J]. PLANT ECOLOGY,2018,219(4):467-479.
APA	Wang, Qing-Wei.,Liu, Cheng-Gang.,Zhou, Wangming.,Qi, Lin.,Zhou, Li.,...&Dai, Limin.(2018).Mobile carbon supply in trees and shrubs at the alpine treeline ecotone.PLANT ECOLOGY,219(4),467-479.
MLA	Wang, Qing-Wei,et al."Mobile carbon supply in trees and shrubs at the alpine treeline ecotone".PLANT ECOLOGY 219.4(2018):467-479.