RT info:eu-repo/semantics/article
T1 Drops in needle production are early-warning signals of drought-triggered dieback in scots pine
A1 Sangüesa Barreda, Gabriel
A1 Gazol, Antonio
A1 Camarero, J. Julio
K1 Crown dynamics
K1 Needle trace method
K1 Pinus sylvestris
K1 Primary growth
K1 31 Ciencias Agrarias
K1 3106 Ciencia Forestal
AB Understanding the mechanisms of drought-induced forest dieback and tree mortality is a priority for predicting forest responses to climate change. However, long-term information on drought impacts on crown dynamics and how it relates to tree water and carbon economy is still lacking. Comparing declining and non-declining Scots pines at the same site, we quantified primary and secondary growth and intrinsic water-use efficiency (WUEi). Further, we reconstructed the needle production and the annual total number of needles using the Needle Trace Method. Here, we reconstructed the apical needles through the assessment of 2460 longitudinal sections. We fitted partial least squares regression models to assess climate influence on primary and secondary growth and needle dynamics, and then linear mixed models using climate covariates and discerning between health status in the 1975–2016 period. Finally, we analyzed drought legacy effects applying a Bayesian hierarchical framework. We detected the highest differences between health tree classes in the annual total number of needles during the warm-dry 1980s. Declining trees responded more negatively to climate than non-declining conspecifics and showed a higher variability of drought legacy effects. We found significant drought legacy effects in the annual total number of needles up to 3 years after a drought. The warm, dry 1980s, that preceded the dieback, showed the highest δ13C values since the 1970s. Declining trees showed higher WUEi than non-declining trees from the 2000s onwards. Our study sheds light on the major role of needle dynamics in dieback episodes and illustrates how past drops in needle production may be interpreted as early warnings of drought-induced dieback in Scots pine.
PB Springer
SN 0931-1890
YR 2023
FD 2023
LK https://uvadoc.uva.es/handle/10324/60541
UL https://uvadoc.uva.es/handle/10324/60541
LA eng
NO Trees, 2023, vol. 37, n. 4, p. 1137-1151
NO Producción Científica
DS UVaDOC
RD 05-jun-2024