DOI: 10.1111/gcb.14338
Scopus记录号: 2-s2.0-85050735432
论文题名: Limited prospects for future alpine treeline advance in the Canadian Rocky Mountains
作者: Davis E.L. ; Gedalof Z.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2018
卷: 24, 期: 10 起始页码: 4489
结束页码: 4504
语种: 英语
英文关键词: alpine treeline
; engelmann spruce
; herbivory
; microclimate
; microsite limitation
; seed addition
; species distributions
; subalpine fir
Scopus关键词: Abies lasiocarpa
; Picea engelmannii
英文摘要: Treeline advance has occurred throughout the twentieth century in mountainous regions around the world; however, local variation and temporal lags in responses to climate warming indicate that the upper limits of some treelines are not necessarily in climatic equilibrium. These observations suggest that factors other than climate are constraining tree establishment beyond existing treelines. Using a seed addition experiment, we tested the effects of seed availability, predation and microsite limitation on the establishment of two subalpine tree species (Picea engelmannii and Abies lasiocarpa) across four treelines in the Canadian Rocky Mountains. The effect of vegetation removal on seedling growth was also determined, and microclimate conditions were monitored. Establishment limitations observed in the field were placed in context with the effects of soil properties observed in a parallel experiment. The seed addition experiment revealed reduced establishment with increasing elevation, suggesting that although establishment within the treeline ecotone is at least partially seed limited, other constraints are more important beyond the current treeline. The effects of herbivory and microsite availability significantly reduced seedling establishment but were less influential beyond the treeline. Microclimate monitoring revealed that establishment was negatively related to growing season temperatures and positively related to the duration of winter snow cover, counter to the conventional expectation that establishment is limited by low temperatures. Overall, it appears that seedling establishment beyond treeline is predominantly constrained by a combination of high soil surface temperatures during the growing season, reduced winter snowpack and unfavourable soil properties. Our study supports the assertion that seedling establishment in alpine treeline ecotones is simultaneously limited by various climatic and nonclimatic drivers. Together, these factors may limit future treeline advance in the Canadian Rocky Mountains and should be considered when assessing the potential for treeline advance in alpine systems elsewhere. © 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/110209
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 Geography, University of Guelph, Guelph, ON, Canada
Recommended Citation:
Davis E.L.,Gedalof Z.. Limited prospects for future alpine treeline advance in the Canadian Rocky Mountains[J]. Global Change Biology,2018-01-01,24(10)