Forest type and height are important in shaping the altitudinal change of radial growth response to climate change

Abstract

Tree radial growth is widely found to respond differently to climate change across altitudinal gradients, but the relative roles of biotic factors (e.g. forest type, height and density) vs. climate gradient remain unclear. We sampled tree rings from 15 plots along a large altitudinal gradient in northeast China, and examined how climate gradient, forest type, height, tree size and density affect: (1) temporal growth variability [mean sensitivity (MS) and standard deviation (SD) of the chronologies], and (2) the relationship of ring width indices (RWI) with historical climate. We used BIC based model selection and variable importance to explore the major drivers of their altitudinal patterns. The results showed that: both growth variability and RWI-climate relationships changed significantly with altitude. Forest height was the most important predictor for altitudinal changes of MS and SD. For RWI-climate relationships, forest type was more important than climate gradient, while height and stem density were weak but necessary predictors. We showed that the altitudinal difference in growth response to climate change cannot be explained by climate gradient alone, and highlight the necessity to examine the influence of biotic factors (which covary with climate across geographic gradient) to better understand forest response to climate change.

Growth Trends of Coniferous Species along Elevational Transects in the Central European Alps Indicate Decreasing Sensitivity to Climate Warming

“…Strongest growth response of P. abies during the last century might be related to different disturbance history of stands, which may have affected the response to warming through the changing canopy structure [40]. Alternatively, species-related growth responses to climate were reported by several authors [39,51,52].…”

Ecoclimates

“…Research in forestry, botany, and ecoclimates focuses on understanding the complex interplay of vegetation and climate. A number of methods investigate the impact of climate and weather on vegetation to explain the dynamics and functioning of plants, for example when exposed to climate warming [Liang et al 2019;Zellweger et al 2020]. Furthermore, climate can have a profound influence on the self-organization of plant ecosystems, which results in the formation of spatial patterns, such as labyrinths and gaps [Bastiaansen et al 2020;Pringle and Tarnita 2017].…”

“…The primary goals of ecoclimate research are to understand the growth response and functioning of vegetation according to changing climatic conditions [Liang et al 2019], the impact of vegetation on thermodynamics and the water cycle [Allan et al 2020], and the feedback loop of vegetation and the climate [Kovenock and Swann 2018]. Many of the current approaches for modeling ecoclimate processes rely on meteorological or macroclimate data, such as free-air temperature or open-field precipitation, that is measured in weather stations.…”

Gains or Losses in Forest Productivity under Climate Change? The Uncertainty of CO2 Fertilization and Climate Effects

“…Heat spells combined with extended drought periods are, however, increasing worldwide and have negatively affected productivity [7], increased mortality [8,9] and induced shifts in species' distribution ranges and species composition [10][11][12]. Temperature increase may also positively affect forest productivity, for example, due to the positive effect on photosynthesis in mountains or high latitudes, which are energy limited and not water limited [13], and also due to the lengthening of the growing season [14,15]. Besides, the continuous increase in atmospheric carbon dioxide (eCO 2 ) acts as a fertilizer for plant growth-termed the "CO 2 fertilization effect" [16] because current CO 2 levels are far from being limiting for the photosynthetic carboxylation reactions in the chloroplasts of C3 plants [17].…”