Critical transitions and early-warning signals in spatial ecosystems
Understanding and predicting critical transitions is one of the central challenges within
the field of `Complexity'. These sudden shifts are exhibited by many complex systems and typically occur as the system passes through a critical threshold. Especially relevant is the question whether the shift can be predicted before this threshold is reached. This is a subtle issue, as even close to such threshold, the complex system in general does not exhibit obvious indications of the approaching transition. This research project concerns
the understanding and prediction of sudden shifts in spatially extended systems, specifically the catastrophic transition of desertification in (semi-)arid ecosystems. A crucial property of such systems is their ability to respond to changes in the environment by adapting the spatial structure; in the case of desertification: the nature of the vegetation pattern. Based on recent advances in field studies, ecological modeling and mathematical methods, a novel approach will be followed by which it is possible to unravel the response of spatial ecosystems to changes in the environment. The aim is to isolate mechanisms by which patterned states may destabilize and initiate a critical transition in response to a (slowly) varying environment, to identify characteristic indicators for these mechanisms, and to analyze the predictive power of these early-warning signals.
Contact information:
Prof. dr. Arjen Doelman, doelman@math.leidenuniv.nl
Prof. dr. Max Rietkerk, m.rietkerk@geo.uu.nl
Jens Rademacher, Jens.Rademacher@cwi.nl