Czech University of Life Sciences of Prague, Department of Forest Ecology, Kamýckà 129, 165 00, Praha 6, Suchdol, Czech Republic; Institut Méditerranéen de Biodiversité et d'Écologie marine et continentale (IMBE), Aix-Marseille Université, CNRS, IRD, Avignon Université, Technopôle Arbois-Méditerranée, Bât. Villemin -BP 80, 13545 Aix-en-Provence cedex 04, France.
GEOLAB CNRS/Université Blaise Pascal/Université de Limoges UMR 6042, 4 rue Ledru, 63057 Clermont-Ferrand cedex 1, France.
Sci Total Environ. 2019 May 10;664:554-566. doi: 10.1016/j.scitotenv.2019.01.404. Epub 2019 Feb 5.
A better understanding of the respective role of key climatic variables on tree growth is crucial for an accurate assessment of how ongoing global changes may affect both dynamics and distribution of forest tree species in the future. The aim of this study was (i) to explore growth patterns of European larch (Larix decidua Mill.) through a network of tree-ring chronologies developed for the French Alps and (ii) to identify the main climatic drivers explaining radial growth. Climate-growth relationships were coupled with a hierarchical analysis. This relationship revealed significant variability expressed spatially by the existence of five clusters, initially discriminated by an elevational contrast related to (i) a negative correlation between summer temperatures and larch growth at lower elevations and (ii) a stronger response of low-elevation larch stands to winter precipitation. In the high-elevation clusters, tree growth depends on previous autumn and current summer temperatures and water supply in July. The differentiation, that portrays a strong geographical coherence, is mainly related to the latitudinal gradient; (i) the northwestern stands are mostly sensitive to high temperatures in summer; (ii) the growth of the southernmost clusters is equally driven by temperatures during autumn, winter, and summers; (iii) the populations of a cluster located in a transitional zone of the inner French Alps, subject to both Mediterranean and Continental influences, exhibit negative correlations to late winter and early spring precipitation. This significant spatial heterogeneity of climate-tree ring relationships in L. decidua clearly underlines the high plasticity of the species to adapt its growth to local climate conditions.
更好地理解关键气候变量对树木生长的各自作用对于准确评估未来全球变化如何影响森林树种的动态和分布至关重要。本研究的目的是：（i）通过为法国阿尔卑斯山建立的树木年轮年表网络探索欧洲落叶松（Larix decidua Mill.）的生长模式；（ii）确定解释径向生长的主要气候驱动因素。气候-生长关系与层次分析相结合。这种关系显示出显著的空间变异性，表现为存在五个聚类，最初通过与（i）夏季温度与较低海拔落叶松生长之间的负相关和（ii）低海拔落叶松林分对冬季降水更强的响应有关的海拔差异来区分。在高海拔聚类中，树木生长取决于前一年秋季和当前夏季的温度以及 7 月的水分供应。这种分化描绘了强烈的地理一致性，主要与纬度梯度有关；（i）西北的林分对夏季高温最为敏感；（ii）最南端聚类的生长同样受到秋季、冬季和夏季温度的驱动；（iii）位于法国阿尔卑斯山内部过渡区的一个聚类的种群受到地中海和大陆影响，其对冬末和早春降水表现出负相关关系。欧洲落叶松中气候-年轮关系的这种显著空间异质性清楚地强调了该物种具有高度的可塑性，能够使其生长适应当地的气候条件。
