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Grantee Research Project Results

Grantee Research Project Results

Dispersal on Structured Fragmented Landscapes

EPA Grant Number: U915235
Title: Dispersal on Structured Fragmented Landscapes
Investigators: Hiebeler, David E.
Institution: Cornell University
EPA Project Officer: Jones, Brandon
Project Period: September 1, 1997 through September 1, 2000
Project Amount: $102,000
RFA: STAR Graduate Fellowships (1997)
Research Category: Fellowship - Mathematics , Academic Fellowships , Environmental Statistics



The objective of this research project is to investigate how non-random patterns of landscape fragmention and dispersal behavior affect population dynamics.


I use local spatial correlations among habitat types in adjacent sites on a discretized landscape map to describe the spatial structure of habitat types. I also have also developed an algorithm thatwhich generates structured heterogeneous landscape maps with specified values of my spatial parameters. Spatially explicit population models are then simulated by computer on these landscape maps. I also have also used the techniques of pair approximations to develop mathematical approximations of the population models on structured landscapes, when dispersal occurs only among adjacent sites. I have shown that for such locally dispersing populations, the spatial correlations of habitat among nearby sites is more important than the actual amount of suitable habitat in the landscape, while for populations with very long—distance dispersal, the opposite is true. I am currently investigating mixed-dispersal models, to determine the effects of occasional long-distance dispersal events on a population thatwhich otherwise disperses locally over short distances. I also am also extending the methods of pair approximations to predict phenomena at larger spatial scales, so that more realistic dispersal models such as exponentially-distributed dispersal may be studied.

Supplemental Keywords:

fellowship, habitat loss and fragmentation, spatially stochastic models, metapopulations, dispersal, cellular automata, population ecology., Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Habitat, Environmental Monitoring, Ecology and Ecosystems, dynamic landscapes, habitat dynamics, landscape context, population demography, ecological consequences, habitat fragmentation, effects of fragmentation

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The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.

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