Modelling the impact of climate and land use change on the geographical distribution of leaf anatomy in a temperate flora

Abstract
Variation in plant functional traits relates to variation in environmental conditions. This paper presents a functional trait centred approach to identify potential impacts of climate and land use change on vegetation. Using species atlas data, we modelled the relative frequencies of species with different leaf anatomies as a function of observed climate and land use data, on a regular spatial grid across Germany. Subsequently, we projected the geographical distribution of leaf anatomy compositions with simulated climate and land use data for the late 21st century under two future scenarios. We used a conditional autoregressive regression model to account for spatial autocorrelation in the compositions, over and above that which could be explained by the environmental predictors. We found a clear relationship between the climatic gradient in water availability and shifts in leaf anatomy composition: Increasing site water deficit was associated with decreasing proportions of species with hygromorphic leaves and increasing proportions of species with scleromorphic and mesomorphic leaves. The shifts in the composition due to land use were only small. Under anticipated climate change the proportions of species with hygromorphic leaves were projected to decrease in all parts of Germany whereas the proportion of species with sclero- and mesomorphic leaves was projected to increase on average. In particular, Germany's south-western and north-eastern areas were projected to experience functional changes in leaf anatomy. Our study highlights the relationship between functional traits and plant species vulnerability to climate change. Our results suggest that the functional trait centred approach can provide a powerful additional modelling exercise to estimate the potential impacts of climate change on vegetation. More research is, however, necessary, and valuable further approaches could include the consideration of different plant ecological strategies within the model and a comparison between the geographical patterns of trait shifts projected from individual species modelling and functional traits modelling.
Year
2011
Category
Refereed journal
Output Tags
SG 2006-2011 WP 3.7 Management of Biodiversity Change