Print PagePlant functional traits are well-established indicators of several life history strategy axes. Their distribution within and among sites has been used to assess mechanisms of community assembly, including habitat filtering and competitive exclusion, while global distributions have shown some correlations with geographic level climate data. Here, we combine data on the distribution of trees across eastern North America and Europe with functional trait data to determine coarse-scale geographic trends in these traits. We ask: 1. Are community mean traits correlated with climate variables (using BioClim data)? 2. Are these relationships consistent between the two regions? 3. Are community metrics (trait spacing and moments of the distribution) related to climate, and if so, are the relationships similar between the two regions? We used literature/eco-informatic derived values for species means wood density, seed size, and maximum height.
Results/Conclusions
We find substantial, significant relationships between mean traits and trait distributions and climatic variables. However, these relationships are often not similar between the tree assemblages of eastern North America and Europe. There is substantial overlap of genera between these two sites, and a similar range of climatic conditions, so there is no strong biological rationale for fundamentally different trait-environment relationships. It is possible that the different biogeographic histories of these regions may have led to these different patterns. Alternatively, it is possible that the measured traits are not critical to performance in these climatic conditions in at least one of the sites, and so observed patterns are simply spurious, or it is possible that different multi-trait trade-offs have led to these observed relationships.
