Glob. Change Biol. (2013)

One way to assess the impact that climate change may have on the future of ecosystems relies on observations of relationships between climate and ecological response. These relationships are used to construct models that simulate the future impacts of altered climate variables, assuming that past climate–ecosystem relationships will hold under future conditions.

Peter Adler, working at Utah State University, and co-workers conducted a rainfall manipulation experiment to test the predictive ability of historical population models for six prairie plant species. These simulations were then compared with predictions generated by a statistical model fitted directly to the experimental data.

For half of the species investigated the historical population models predicted population growth rates in the experimental plots as well as, or better than, the direct statistical models. However, results were less impressive for the remaining species; probably due to weak historical precipitation–plant performance correlations and insufficient spatial replication. In general the experiment suggests that we can have some confidence in extrapolating historical relationships to predict population responses to climate change, provided that the historical correlations are strong and based on well-replicated observations.