Ecological contingency in the effects of climate change on plant communities: Reconciling experimental, historical, interannual, and geographic evidence

Background/Question/Methods

Which plant communities within a heterogeneous landscape will respond most (and least) to a given climatic perturbation, and why?  My collaborators and I have explored this question using experimental and observational approaches.  We have focused on the prediction that communities on infertile serpentine soils will be relatively climate-insensitive because of the prevalence of a slow-growing, stress-tolerant plant functional strategy in such settings.  

Results/Conclusions

We have found lower interannual variability in community composition, lesser geographic variation over large-scale climate gradients, and unresponsiveness to experimental rainfall additions, in plant communities on infertile serpentine compared to nearby normal soils.  We also find correlative evidence supporting the predicted role of plant functional traits.  However, an analysis of multi-decadal change in plant communities -- the most direct source of evidence with respect to future climate change -- does not support the prediction of lesser community change on infertile soils.  Our current work focuses on explaining this paradox.