HR: 0830h
AN: H51D-1110    [PDF]
TI: Dynamical Interactions Between Human Populations and Landscapes in Barrier Island Environments
AU: * McNamara, D E
EM: dmcnamara@ucsd.edu
AF: Complex Systems Laboratory, Cecil and Ida Green Institute of Geophysics and Planetary Physics, University of California-San Diego, La Jolla, CA 92093-0225 United States
AU: Werner, B T
EM: bwerner@ucsd.edu
AF: Complex Systems Laboratory, Cecil and Ida Green Institute of Geophysics and Planetary Physics, University of California-San Diego, La Jolla, CA 92093-0225 United States
AB: Although much research has focused on how humans affect landscapes or how landform processes affect humans, little attention has been paid to dynamical interactions between the two. Based on the hypothesis that landscape and human dynamics both self-organize into a temporal hierarchy of scale-separated behaviors, we model the evolution of a coupled human population and barrier island system. Barrier islands are represented as a series of alongshore nodes, with each node specifying the width, height, cross-shore position, and profile of the island and the beach width, dune position and dune height. These characteristics evolve according to rules governing sediment transport during acretionary phases, erosion from storms, dune growth and migration, tidal delta formation, overwash, inlet formation, alongshore sediment transport, and dune and backbarrier vegetation growth. At each of these nodes, human populations and their cultural accoutrements are represented by mean property value, fraction of land used for tourist accommodations and tourist population. The dynamics of these variables is determined by simulating the competition for economic resources amongst the local population and the desire of the tourist population for adequate recreational beaches. The human and barrier subsystems are coupled through beach replenishment and a dependence of tourist population on beach width. Model results fall into three general categories of dynamical behavior, as classified by the (linearized) time scale of recovery from perturbations for the uncoupled systems. When the time scale for barrier islands is much less than that of the human population, the long-time-scale evolution of the barrier island follows human dynamics. In the reverse case, the long-time-scale evolution of the human population follows barrier dynamics. When the time scales are similar, new long-time-scale, spatially varying behavior of the coupled system emerges. Implications for prediction and optimization strategies will be discussed.
DE: 1803 Anthropogenic effects
DE: 1824 Geomorphology (1625)
SC: Hydrology [H]
MN: 2003 Fall Meeting