Climate warming differently affects Larix decidua ring formation at each end of a French Alps elevational gradient

Abstract

& Key message The ongoing global warming tends to reduce Larix decidua radial growth and ring wood density at the bottom of an elevational gradient in the French Alps, while it has a less marked effect at the top. & Context The ongoing climate warming affects most tree species across their biogeographic distribution range. The bottom and the top of an elevational gradient are appropriate environments to observe the effect of climate warming in contrasted temperature conditions. & Aims To retrospectively study the effect of the ongoing climate warming on Larix decidua trees located in warm and cold conditions, i.e., at the bottom (1200 m) and the top (2300 m) of an elevational gradient, respectively. & Methods Dendroecological analysis of two groups of Larix decidua trees located at very low (1200 m) and very high (2300 m) elevations. Construction of climatic response curves for annual ring variables. Decomposition of the variance of the response models into their high and low frequency components. & Results At Briançon, in the French Alps, the increase of the daily maximum temperature during the last 50 years is already almost 3°C for the March-October period. The results reveal contrasted behaviors at both ends of the investigated elevational gradient. Basal area increment, ring width, and their earlywood and latewood components increase or level off at the top of the gradient, while they all strongly decrease at the bottom. At the bottom, the low frequency warming effect explains the recent ring width decrease, with no influence of the high frequency temperature variation. At the top, both the low frequency warming effect Handling Editor: Patrick Fonti This article is part of the topical collection on Wood formation and tree adaptation to climate

Phenotypic plasticity of European larch radial growth and wood density along a‐1,000 m elevational gradient

“…Here we compared different methods used at the successive steps of the RN construction, for their ability to maximize the number of trees with significant RN. First we tested several detrending methods: we used no correction, negative exponential curve (Cook & Kairiukstis, 1990;Fritts, 1976) and regional curve standardization (RCS; Esper et al 2003), with residual RCS and ratio RCS (Esper et al, 2003;Rozenberg, Chauvin, et al, 2020). For the negative exponential function we used the dendrochronology library in R, dplR (Bunn, 2008).…”

“…The climatic data are daily values of minimum and maximum temperature and precipitation coming from the closest Météo-France weather station (French national weather service; Rozenberg, Chauvin, et al, 2020 we used the Briançon data only. For each plot we adjusted the Briançon climatic time-series from the elevation effect, as in (Latreille et al, 2017;Rozenberg, Chauvin, et al, 2020) using the on-site climatic data measured since 2008 at each plot.…”

“…According to (Rozenberg, Chauvin, et al, 2020), this global warming effect is stronger for tree response at low elevation than at high elevation: global warming reveals the potential of plasticity of larch.…”

Environmental and developmental factors driving xylem anatomy and micro‐density in black spruce

“…The second is at the micro‐density level, integrating density measurements at specific locations within a tree ring. The responsiveness of wood density to variations in environmental factors has long been exploited by dendroclimatologists to detect regional climatic signals (Wimmer & Grabner, 2000; Gagen et al ., 2006; Drew et al ., 2013) and to assess the effects of climate change along elevational gradients (Rozenberg et al ., 2020). These dendrochronological studies have unravelled complex response patterns at inter‐annual scales.…”

Physiological and anatomical responses to drought stress differ between two larch species and their hybrid

“…Climate change has drastic effects on the survival, reproduction, growth and productivity of trees. High temperatures together with water shortage are major stress factors, which cause physiological as well as structural changes (Breda et al 2006;Allen et al 2015;McDowell and Allen 2015;Mencuccini and Binks 2015;McDowell et al 2016;Klein et al 2019;Rozenberg et al 2020). There is an expectation for forests to mitigate climate change through carbon storage and sequestration, protect against erosion, soil and snow slides; however, the demand for wood, particularly from conifers such as larch, has never been higher.…”