Soil nutrients influence growth response of temperate tree species to drought

Summary Soil properties can buffer forest response to global climate change. However, it is unclear how soil characteristics, water availability and their interactions can affect drought response of trees. The aim of this study was to assess the influence of soil nutrients and physical soil properties on the growth sensitivity of Fagus sylvatica , Quercus spp., Fraxinus excelsior , Abies alba, Picea abies and Pinus sylvestris to drought in Central Europe. Yearly growth data from increment cores were obtained from 538 trees and combined with forest inventory and soil data at 52 sites covering a large gradient of water availability and C/N ratios in soil. Linear mixed‐effects models were used to assess the species‐specific growth responses to climate and soil properties for the period 1957–2006. The growth of the species was further projected across the full range of C/N and water availability observed at 1029 sites where soil and species cover‐abundance data were available. Temperature, water and nutrient availability (C/N) were the most important factors for tree growth. Drought and low nutrient availability significantly reduced the growth of beech, ash, fir and spruce along the gradient. In contrast, the growth of pine and oak was little reduced on poor and dry sites, hence showing their competitive advantage over nutrient‐demanding species under such conditions. The growth of ash and pine was enhanced at sites with high species abundance, whereas an opposite response was found for spruce. No clear relationships between growth and species abundance were found for beech, oak and fir. Synthesis . Our results suggest that assessing tree responses to climate change without considering simultaneously soil properties and climate may be misleading since soil nutrients can influence growth response of trees to drought. A detailed analysis of the influence of the soil characteristics on growth responses of trees is necessary to understand the sensitivity of tree species to global climate change.