Landscape Ecology

, Volume 22, Issue 6, pp 867–881 | Cite as

Modeling scale-dependent landscape pattern, dispersal, and connectivity from the perspective of the organism

  • Steven Walters
Research Article


Understanding the impacts of habitat fragmentation on dispersal is an important issue in landscape and conservation ecology. Here I examine the effects of fine- to broad-scale patterns in landscape structure on dispersal success of organisms with differing life-history traits. An individual-based model was used to simulate dispersal of amphibian-like species whose movements were driven by land cover and moisture conditions. To systematically control spatial pattern, a landscape model was created by merging simulated land cover maps with synthetic topographic surfaces. Landscapes varied in topographic roughness and spatial contagion in agriculture and urban land cover. Simulations included three different species types that varied in their maximum potential dispersal distances by 1-, 2-, or 4-fold. Two sets of simulations addressed effects of varying aspects of landscape structure on dispersal success. In the first set of simulations, which incorporated variable distances between breeding patches, dispersal success was lowest for all species types when anthropogenic cover was patchily distributed. In the second set, with interpatch distances held constant as landscape composition varied, dispersal success decreased as anthropogenic cover became spatially contagious. Both sets revealed strong main effects of species characteristics, interpatch distances and landscape composition on dispersal success; furthermore, scale-dependent patterns in land cover and moisture gradients had a stronger effect on longer- than shorter-ranging species types. Taken together, these simulations suggest that heuristic conservation strategies could potentially be developed based on important but limited life history information.


Landscape fragmentation Metapopulation persistence Life history × landscape pattern interactions Matrix structure Landscape context effects Individual-based models 



I want to thank Robert Gardner, Philip Townsend, Steven Seagle, J. Edward Gates and Robert Costanza for providing invaluable guidance in conducting the present study. This research was partially funded by a fellowship from the National Network for Environmental Management Studies (NNEMS) Program, US Environmental Protection Agency (US EPA). Critical reviews by Jason Grear, Diane Nacci, Matthew Nicholson, and two anonymous reviewers proved most valuable in revising the manuscript. Although the research has been partly funded by the US EPA, it has not been subjected to Agency-level review, and therefore does not necessarily reflect the views of the Agency. Mention of commercial products does not constitute endorsement or recommendation for use. This is NHEERL contribution number AED-06-007.


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Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  1. 1.Atlantic Ecology DivisionNational Health and Environmental Effects Research Laboratory, Office of Research and Development, US Environmental Protection AgencyNarragansettUSA
  2. 2.Department of Urban Design and PlanningUniversity of WashingtonSeattleUSA

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