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Linking richness, community variability, and invasion resistance with patch size
Piers K Dunstan1, Craig R Johnson
1School of Zoology and Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, GPO Box 252-05 Hobart, Tasmania, Australia 7001. Piers.Dunstan@csiro.au
Ecology
|December 16, 2006
Summary
Patch size significantly impacts ecological communities. Larger patches allow dominant species to reduce diversity and invasion resistance, while smaller patches maintain higher variability regardless of species richness.
Area of Science:
- Ecology
- Ecological modeling
- Invasion biology
Background:
- Community dynamics influence invasion success.
- The role of patch size in invasion outcomes for communities with identical species pools remains unexplored.
Purpose of the Study:
- To investigate the effects of patch size on community variability, species richness, and invasion resistance using a spatial model.
- To understand how these ecological variables interact and are influenced by spatial scale.
Main Methods:
- Utilized an empirically validated spatial model of a marine epibenthic community.
- Examined the relationships between patch size, community variability, species richness, and invasion resistance.
Main Results:
- The relationship between community variability and species richness is patch size-dependent.
- In small patches, variability decreases with richness; in large patches, variability increases with richness.
- Invasion resistance strongly correlates with community variability, with the relationship mediated by patch size.
Conclusions:
- Patch size fundamentally alters the interplay between species richness, community variability, and invasion resistance.
- Emergent community properties, including invasion resistance, are shaped by individual species traits and spatial context (patch size).
- A continuum of relationships exists between these ecological variables, influenced by spatial scale and species-specific mortality-size dynamics.
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