title: Population dynamics in spatially heterogeneous systems with drift: The generalized contact process.
abstract: We investigate the time evolution and stationary states of a stochastic, spatially discrete, population model (contact process) with spatial heterogeneity and imposed drift (wind) in one and two dimensions. We consider in particular a situation in which space is divided into two regions: an oasis and a desert (low and high death rates). Carrying out computer simulations we find that the population in the (quasi) stationary state will be zero, localized, or delocalized, depending on the values of the drift and other parameters. The phase diagram is similar to that obtained by Nelson and coworkers from a deterministic, spatially continuous model of a bacterial population undergoing convection in a heterogeneous medium.
authors.affiliation: Department of Physics, Rutgers University, New Brunswick, New Jersey, 08854, USA.
authors.forename: Jaewook
authors.initials: J
authors.lastname: Joo
authors.forename: Joel L
authors.initials: JL
authors.lastname: Lebowitz
mesh_terms: D000465:Algorithms; D000818:Animals; D005075:Biological Evolution; D003198:Computer Simulation; D004641:Emigration and Immigration; D014644:Genetic Variation / Q000235:genetics; D005828:Genetics, Population; D006801:Humans; D008954:Models, Biological; D015233:Models, Statistical; D009026:Mortality; D009068:Movement / Q000502:physiology*; D013269:Stochastic Processes