The shape of the spatial kernel and its implications for biological invasions in patchy environments
Tom Lindström1, Nina Håkansson, Uno Wennergren
1IFM Theory and Modelling, Linköping University, 581 83 Linköping, Sweden.
Proceedings. Biological Sciences
|November 5, 2010
Summary
Invasion speed depends on spatial context. The dispersal kernel
Area of Science:
- Ecological modeling
- Epidemiological dynamics
- Spatial statistics
Background:
- Ecological and epidemiological invasions are spatial processes.
- Dispersal is often described by a spatial kernel (shape and width).
- Spatial structure of habitats or populations influences spread.
Purpose of the Study:
- Investigate the correlation between invasion speed and distance-dependent dispersal.
- Analyze how spatial patterns affect invasion dynamics.
- Develop a novel method for analyzing point-pattern landscapes.
Main Methods:
- Simulation study of invasions using spatial kernels.
- Analysis of point-pattern landscapes using spectral representation (continuity and contrast).
- Application to empirical data (tree and farm distributions in Sweden).
Main Results:
- Spatial kernel shape is less critical in randomly distributed patches for invasion speed.
- Kernel shape becomes important in non-randomly distributed patches, especially with high contrast.
- Invasion speed is dependent on the interplay between spatial kernel effects and spatial structure.
Conclusions:
- Invasion speed is intricately linked to the spatial context.
- The influence of the spatial kernel is inseparable from the underlying spatial structure.
- Accurate empirical data requires knowledge of both kernel parameters and spatial structure.
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