Dissertation

Lines in the sand: behaviour of self-organised vegetation patterns in dryland ecosystems

Vast, often populated, areas in dryland ecosystems face the dangers of desertification.

Author

Bastiaansen, R.

Date

27 June 2019

Links

Thesis in Leiden Repository

Vast, often populated, areas in dryland ecosystems face the dangers of desertification. Loosely speaking, desertification is the process in which a relatively dry region loses its vegetation - typically as an effect of climate change. As an important step in this process, the lack of resources forces the vegetation in these semi-arid areas to organise itself into large-scale spatial patterns. In this thesis, these patterns are studied using conceptual mathematical models, in which vegetation patterns present themselves as localised structures (for example pulses or fronts). These are analysed using mathematical techniques from (geometric singular) perturbation theory and via numerous numerical simulations. The study of these ecosystem models leads to new advances in both mathematics and ecology.

• asymptotic analysis
• changing parameters
• desertification
• ecosystem resilience
• exponential dichotomies
• geometric singular perturbations
• multistability
• pattern formation
• reaction advection diffusion
• semi-strong pulse dynamics