Impact of climate change on tree-ring growth of Scots pine, common beech and pedunculate oak in northeastern Germany

Abstract

Tree growth depends, among other factors, largely on the prevailing climatic conditions. Therefore, changes to tree growth patterns are to be expected under climate change. Here, we analyze the tree-ring growth response of three major European tree species to projected future climate across a climatic (mostly precipitation) gradient in northeastern Germany. We used monthly data for temperature, precipitation, and the standardized precipitation evapotranspiration index (SPEI) over multiple time scales (1, 3, 6, 12, and 24 months) to construct models of tree-ring growth for Scots pine (Pinus sylvestris L.) at three pure stands, and for common beech (Fagus sylvatica L.) and pedunculate oak (Quercus robur L.) at three mature mixed stands. The regression models were derived using a two-step approach based on partial least squares regression (PLSR) to extract potentially well explaining variables followed by ordinary least squares regression (OLSR) to consolidate the models to the least number of variables while retaining high explanatory power. The stability of the models was tested through a comprehensive calibration-verification scheme. All models were successfully verified with R²s ranging from 0.21 for the western pine stand to 0.62 for the beech stand in the east. For growth prediction, climate data forecasted until 2100 by the regional climate model WETTREG2010 based on the A1B Intergovernmental Panel on Climate Change (IPCC) emission scenario was used. For beech and oak, growth rates will likely decrease until the end of the 21 st century. For pine, modeled growth trends vary and range from a slight growth increase to a weak decrease in growth rates. The climatic gradient across the study area will possibly affect the future growth of oak with larger growth reductions towards the drier east. For beech, site-specific adaptations seem to override the influence of the climatic gradient. We conclude that Scots pine has great potential to remain resilient to projected climate change without any greater impairment, whereas common beech and pedunculate oak will likely face lesser growth under the expected warmer and dryer climate conditions. The results call for an adaptation of forest management to mitigate the negative effects of climate change for beech and oak.

Drought Stress Distribution Responses of Continental Beech Forests at their Xeric Edge in Central Europe

“…Since this region represents a spatially diverse climatic environment, a more detailed knowledge on the functional distribution responses of forest stands is acutely needed [3,26,56]. The drought threshold value and the relative drought response range can be used as indicators to assess regional climate vulnerability of beech forests.…”

“…These forests play a significant role in European forested landscapes, having a high level of spatial variation from west to east as well as a high level of heterogeneity under diverse climatic and local environmental conditions [2,5,13,[15][16][17]22,23]. Ecological constraints at the lowest altitudinal limit of beech forest distribution were found in several northern, southern, and eastern regions of Europe [13,[15][16][17][24][25][26]. Additionally, beech forests are geographically and ecologically limited by climate in the Pannonian Region of the Carpathian Basin in Central Europe [4,[27][28][29][30][31].…”

Environmental drivers interactively affect individual tree growth across temperate European forests

“…Previous studies have explored how global-change drivers affect tree growth, but mostly on a restricted geographical scale (Bauwe, Jurasinski, Scharnweber, Schröder, & Lennartz, 2016;Braun et al, 2017;Ibáñez, Zak, Burton, & Pregitzer, 2018;Martinez-Vilalta, Lopez, Adell, Badiella, & Ninyerolas, 2008). Tree growth studies covering larger geographical scales and taking into account interactions between global-change drivers at the same time (e.g., Laubhann et al, 2009;Solberg et al, 2009) are relatively scarce.…”

Functional Response Trait Analysis Improves Climate Sensitivity Estimation in Beech Forests at a Trailing Edge

“…During the growing season beech tree growth is consistently limited by high temperature and low precipitation at the southern edge of their European distribution [25,27]. Nevertheless, site-specific adaptation of the species can compensate for the unfavorable ecological or functional effects of decreasing precipitation [63], as it was also detected in the current investigation.…”