Using structured population models to understand multispecies communities
Many classic questions in population, community, and evolutionary ecology concern the influence of environmental variation. IPMs are a useful framework for studying how the diversity, structure, and dynamics of multispecies plant communities are affected by environmental variability. Here we illustrate how IPMs can be constructed from individual-level permanent quadrat maps and used to exame the role of environmental variability in semi-arid plant communities.
Mean-field approximations allow spatially implicit IPMs to approximate well the average behavior of individual-based models that become computationally intractable at landscape scale. A new Poisson approximation allows the models to include demographic stochasticity as well as environmental stochasticity. Methods from functional data analysis improve our ability to identify biotic and abiotic factors driving current demographic performance. Applications include identifying the spatial scale of neighborhood competition, identifying the current impacts of past environmental conditions, modeling size-environment interactions, and projecting the long-lasting impacts of environmental variation on individuals and populations.