University of Helsinki
Present-day landscape patterns may provide information on past dynamics of the landscape. Spatial ecologists have taken advantage of this for a long time, for instance to infer colonization rates and dispersal distances of species from their present-day spatial distributions and occurrence patterns.
Inferring past dynamics from present-day patterns gets more complicated if multiple landscape elements have been simultaneously on the move. In this case, it may be helpful to reconstruct and simulate past landscape dynamics, to understand how different dynamic elements must have interacted in the past to produce the present-day pattern. Methods that reconstruct past interactions may help us to understand complex dynamics, without having to wait for years for the accumulation of time series data.
In our recent publication in the field of spatial ecology, we tested this by using data on a well-studied epiphytic lichen, Lobaria pulmonaria. For our study area, fire scar data existed on the timings and locations of forest fires for a 400-year time period. Given this known landscape disturbance history, we simulated and calibrated the dynamics of L. pulmonaria host trees and L. pulmonaria colonizations so that they resulted in patterns that match with present-day data (locations of L. pulmonaria occurrences and host trees). Our resulting colonization model of L. pulmonaria performed well against a model fitted to time series data.
We hope to inspire further studies on complex dynamics that utilize multiple types of information contained in present-day landscapes.