Traveling waves and spatial patterns from dispersal on homogeneous and gradient habitats
Authored by George P Malanson, Nancy Rodriguez
Date Published: 2018
DOI: 10.1016/j.ecocom.2017.12.001
Sponsors:
United States National Science Foundation (NSF)
Platforms:
No platforms listed
Model Documentation:
Other Narrative
Mathematical description
Model Code URLs:
Model code not found
Abstract
Models of dispersal for response to global climate change can refer to
theory on traveling waves developed for invasions. The relevance of this
theory may depend on its density- versus habitat dependence, but it has
not considered environmental gradients nor related feedbacks. An agent
based simulation model (ABM) for a plant species or vegetation type is
developed here, focusing on properties of traveling waves. The ABM
simulated no-tailed, thin-tailed, and fat-tailed dispersal kernels
(random uniform, Gaussian, and Cauchy kernels, respectively).
Probabilities were based on either population density or habitat, and
for the latter as homogeneous or on a gradient, and if a gradient
positive feedback from populations to the habitat was added to represent
process at ecotones such as a positive feedback switch or the stress
gradient hypothesis (SGH) feedback. The uniform and Gaussian kernels
produced traveling waves with constant speed, but the fat-tailed Cauchy
kernel produced traveling waves that accelerated and also flattened as
the low-probability. portion of wave accelerated fastest. On a gradient,
when populations approached the limit of habitability the waves
steepened and stopped traveling. The effect of SGH feedback on traveling
wave slopes depends on the dispersal kernel. With strong facilitation on
the gradient, greater variety of spatial patterns were able to develop
among the replicate simulations of the fat-tailed kernel when it
flattened to a greater spatial extent of low probability presence. In
addition to the heterogeneity of the habitat and its modification by
facilitation, the details of dispersal can also affect the feedback
between spatial pattern and the establishment process that will affect
the rate of advance of a species or an ecotone into new territory. (C)
2017 Elsevier B.V. All rights reserved.
Tags
Agent based model
Migration
Dynamics
Dispersal
Model
feedbacks
Ecotone
Climate-change
Spread
Forest
Phase-transitions
Range
Environmental gradient
Traveling
waves
Alpine treeline ecotones