PARENT SESSION
Thursday, August 10, 1:30-5:00 pm
Symposium 21 - Revisiting the 'stability icon': upstart approaches to modeling resilience
Steamboat, Mezzanine Level, Cook Convention Center
Organized by: DL DeAngelis (ddeangelis@bio.miami.edu), SF Railsback, V Grimm, and U Berger
This symposium reviews how "upstart" approaches of bottom-up, pattern-oriented simulation modeling are allowing ecologists to gain a better understanding of one of the most important "icons" of ecology, stability, and how aspects of stability at the systems level, such as resilience, emerge from mechanisms at the individual level.
Stability and forest dynamics: about the robustness of mangrove succession.
Berger, Uta*,1, Piou, Cyril1, 1 Center for Tropical Marine Ecology, Bremen, Germany
ABSTRACT- The occurrence of alternative equilibria in communities has been a theme among ecologists since the late 1960s. From the perspective of classical modelling, there are two alternatives how communities may shift from one stable state to another: (1) a shift of state variables such as population densities may occur but the environment remains constant, and (2) underlying parameters or environmental 'drivers' change and determine the behaviour of state variables and their interactions. Focusing on succession, a combination of both approaches is worthwhile, because increasing abundances of a particular species may alter the parameter values for the rest of the community. Using the spatially-explicit, individual-based model KiWi which describes the dynamics of neotropic mangrove forests, we demonstrate the potential of this modelling approach for analysing the role of neighbourhood effects and the importance of the spatiality of ecological processes on the shift between different succession trajectories. Using the availability of propagules as an example, we will furthermore show how stochasticity supplies the final impetus for the arrival at alternative succession stages after perturbations.
Key words: robustness, individual based modeling, mangrove forest succession