Seminar in PSA 106 at 3:40p.m.

ABSTRACT:

Ecological stoichiometry studies the balance of energy and multiple chemical elements in ecological interactions in order to establish how the laws of thermodynamics affect food-web dynamics and nutrient cycling in ecosystems. We will show that the incorporation of an explicit stoichiometric framework in a model featuring habitat heterogeneity can provide valuable insight into population growth dynamics and dispersal. The first model describes a simple situation where a resource is separated into two patches by a barrier. The growth of each resource patch is limited by soil quality and self-crowding. The consumer disperses between the two patches and is not affected by the barrier. In turn, the growth of the consumer is limited by the phosphorous content of the acquired resource. A brief mathematical analysis of this model and extensive simulations are performed. Biological implications such as an observed ``rescue effect" and the local extinction of a single patch will be discussed. A second model featuring delayed nutrient recycling and consumer dispersion is introduced and simulated using MATLAB.