From individuals to populations and communities
Pierre Auger

UMR CNRS 5558
Laboratoire de Biometrie, Genetique et Biologie des Populations
Universite Claude Bernard Lyon 1
43, boulevard du 11 Novembre 1918
69622 Villeurbanne cedex, FRANCE
pauger@biomserv.univ-lyon1.fr

Eva Sánchez
Departamento de Matemáticas, E.T.S.I. Industriales, U. Politécnica de Madrid
José Gutiérrez Abascal 2.
28806 Madrid, Spain
esanchez@math.etsii.upm.es


Ecological systems are made up of different levels of organization, the individual, the population and the community levels. Dealing with different levels of organization signifies that one must study models in which the dynamics in the different levels must be coupled. Important differences in the orders of magnitude of the spatial and time scales involved in these ecological levels makes possible to use perturbation methods in order to reduce the dimension of the complete model. Aggregation methods are important in Ecology because one can obtain at each level of organization an approximate dynamical system governing a few number of global variables which is more tractable than the complete system involving a large number of state variables. The session is devoted to the presentation of reduction and aggregation methods in Ecological modelling with a special emphasis on applications such as spatial population and community dynamics (spatial aggregation), coupled individual and population dynamics, and coupled population and community dynamics.


List of presentations