English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/113812
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:
Title

To die or not to die: Early warnings of tree dieback in response to a severe drought

AuthorsCamarero, Jesús Julio ; Gazol Burgos, Antonio ; Sangüesa-Barreda, G. ; Oliva, Jonás; Vicente Serrano, Sergio M.
Keywordsblue-stain fungi
critical transitions
drought stress
early warning signals
forest decline
generalized additive mixed models
mortality
plant–climate interactions
tree death
Issue Date2015
PublisherWiley-Blackwell
CitationJournal of Ecology 103(1): 44-57 (2015)
AbstractSome disturbances can drive ecological systems to abrupt shifts between alternative stages (tipping points) when critical transitions occur. Drought-induced tree death can be considered as a nonlinear shift in tree vigour and growth. However, at what point do trees become predisposed to drought-related dieback and which factors determine this (tipping) point? We investigated these questions by characterizing the responses of three tree species, silver fir (Abies alba), Scots pine (Pinus sylvestris) and Aleppo pine (Pinus halepensis), to a severe drought event. We compared basal area increment (BAI) trends and responses to climate and drought in declining (very defoliated and dying) vs. non-declining (slightly or not defoliated) trees by using generalized additive mixed models. Defoliation, BAI and sapwood production were related to functional proxies of tree vigour measured at the onset and end of the drought (non-structural carbohydrate concentrations, needle N content and C isotopic discrimination, presence of wood-inhabiting fungi). We evaluated whether early warning signals (increases in synchronicity among trees or in autocorrelation and standard deviation) could be extracted from the BAI series prior to tree death. Declining silver fir and Scots pine trees showed less growth than non-declining trees one to three decades, respectively, before the drought event, whereas Aleppo pines showed growth decline irrespective of tree defoliation. At the end of the drought period, all species showed increased defoliation and a related reduction in the concentration of sapwood soluble sugars. Defoliation was constrained by the BAI of the previous 5 years and sapwood production. No specific wood-inhabiting fungi were found in post-drought declining trees apart from blue-stain fungi, which extensively affected damaged Scots pines. Declining silver firs showed increases in BAI autocorrelation and variability prior to tree death. Synthesis. Early warning signals of drought-triggered mortality seem to be species specific and reflect how different tree species cope with drought stress. Highly correlated declining growth patterns during drought can serve as a signal in silver fir, whereas changes in the content of sapwood soluble sugars are suitable vigour proxies for Scots and Aleppo pines. Longer growth and defoliation series, additional vigour parameters and multi-species comparisons are required to understand and predict drought-induced tree death. Early warning signals of drought-triggered mortality seem to be species specific and reflect how different tree species cope with drought stress. Highly correlated declining growth patterns during drought can serve as a signal in silver fir, whereas changes in the content of sapwood soluble sugars are suitable vigour proxies for Scots and Aleppo pines. Longer growth and defoliation series, additional vigour parameters and multi-species comparisons are required to understand and predict drought-induced tree death.
Publisher version (URL)http://dx.doi.org/10.1111/1365-2745.12295
URIhttp://hdl.handle.net/10261/113812
DOI10.1111/1365-2745.12295
ISSN1365-2745
Appears in Collections:(IPE) Artículos
Files in This Item:
File Description SizeFormat 
Camarero_To die or not to die_Journal of Ecology2015.pdf7,43 MBAdobe PDFThumbnail
View/Open
Show full item record
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.