DOI: 10.1111/gcb.14561
Scopus记录号: 2-s2.0-85060886396
论文题名: Tree rings provide no evidence of a CO 2 fertilization effect in old-growth subalpine forests of western Canada
作者: Hararuk O. ; Campbell E.M. ; Antos J.A. ; Parish R.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2019
卷: 25, 期: 4 起始页码: 1222
结束页码: 1234
语种: 英语
英文关键词: climate change
; CO 2 fertilization effect
; dendroecology
; global warming
; old-growth forests
; tree growth
; tree rings
英文摘要: Atmospheric CO 2 concentrations are now 1.7 times higher than the preindustrial values. Although photosynthetic rates are hypothesized to increase in response to rising atmospheric CO 2 concentrations, results from in situ experiments are inconsistent in supporting a CO 2 fertilization effect of tree growth. Tree-ring data provide a historical record of tree-level productivity that can be used to evaluate long-term responses of tree growth. We use tree-ring data from old-growth, subalpine forests of western Canada that have not had a stand-replacing disturbance for hundreds of years to determine if growth has increased over 19th and 20th centuries. Our sample consisted of 5,858 trees belonging to five species distributed over two sites in the coastal zone and two in the continental climate of the interior. We calculated annual increments in tree basal area, adjusted these increments for tree size and age, and tested whether there was a detectable temporal trend in tree growth over the 19th and 20th centuries. We found a similar pattern in 20th century growth trends among all species at all sites. Growth during the 19th century was mostly stable or increasing, with the exception of one of the coastal sites, where tree growth was slightly decreasing; whereas growth during the 20th century consistently decreased. The unexpected decrease in growth during the 20th century indicates that there was no CO 2 fertilization effect on photosynthesis. We compared the growth trends from our four sites to the trends simulated by seven Earth System Models, and saw that most of the models did not predict these growth declines. Overall, our results indicate that these old-growth forests are unlikely to increase their carbon storage capacity in response to rising atmospheric CO 2 , and thus are unlikely to contribute substantially to offsetting future carbon emissions. © 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/117463
Appears in Collections: 气候变化与战略
There are no files associated with this item.
Recommended Citation:
Hararuk O.,Campbell E.M.,Antos J.A.,et al. Tree rings provide no evidence of a CO 2 fertilization effect in old-growth subalpine forests of western Canada[J]. Global Change Biology,2019-01-01,25(4)