The local dynamics of a tri-trophic system

摘要: A lumped parameter model to describe the local dynamics of a tri-trophic chain (resource, herbivore, carnivore) is presented. The time evolution system determined by ordinary differential equations and written in terms normalized biomass three levels chain. In these we have introduced bio-ecological parameters (specific rates, conversion factors) two p q which measure efficiency interaction processes (e.g. predation processes). stability persistence analysis solutions has been performed assuming that: (i) are given (in other work suggest procedures estimate them from individual data demographic models); (ii) function determining growth first level functional responses second third abundances levels, respectively, characterized only shape response not analytical expressions; (iii) considering behavioural as bifurcation parameters. regions (p, q) plane existence non-negative steady states, those limit cycles determined. Results numerical simulations shown.