Declining hydraulic performances and low carbon investments in tree rings predate Scots pine drought-induced mortality
Heres, Ana-Maria (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Camarero, Jesús Julio (Instituto Pirenaico de Ecología)
Claramunt López, Bernat (Universitat Autònoma de Barcelona. Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia)
Martínez Vilalta, Jordi, 1975- (Universitat Autònoma de Barcelona. Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia)

Date:	2014
Abstract:	Widespread episodes of drought-induced tree mortality are predicted to become more frequent as climate becomes warmer and drier. Nevertheless, growth trends and their links to changes in wood anatomy before tree dies are still poorly understood. Wood anatomical features provide valuable information that can be extracted to infer the mechanisms leading to tree death. In this study, we characterize drought-induced mortality affecting two Scots pine (Pinus sylvestris) sites (Prades and Arcalís) located in the North Eastern Iberian Peninsula. Co-occurring now-dead and living Scots pine trees were sampled and their wood anatomical features were measured and compared. We aimed to detect differences in anatomical features between living and dead trees, and to infer past physiological performances that might have determined their subsequent death or survival. Now-dead trees showed lower tracheid and resin duct production, and smaller radial lumen diameters than co-occurring living trees. At the more xeric Prades site, these anatomical differences were larger and chronic, i. e. were observed over the three studied decades, whilst they were less pronounced at the other, more mesic Arcalís site, where tree mortality episodes were more recent. This indicates that dead trees' hydraulic conductivity was severely affected and that carbon investment in xylem formation and resin duct production was constrained prior to tree death. Our findings show that both hydraulic deterioration and low carbon allocation to xylem formation were associated to drought-induced mortality in Scots pine. Nevertheless, the temporal dynamics of these processes differed between populations as a function of site climatic conditions.
Grants:	Ministerio de Educación y Ciencia CGL2007-60120 Ministerio de Ciencia e Innovación CSD2008-00040 Ministerio de Ciencia e Innovación CGL2010-16373 Ministerio de Ciencia e Innovación CGL2011-26654
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Drought ; Mortality ; Scots pine ; Tracheid ; Tree ring ; Wood anatomy
Published in:	Trees, structure and function, Vol. 28 Issue 6 (Dec. 2014) , p. 1737-1750, ISSN 0931-1890

DOI: 10.1007/s00468-014-1081-3

Post-print 40 p, 956.0 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > CREAF (Centre de Recerca Ecològica i d'Aplicacions Forestals)
Articles > Research articles
Articles > Published articles