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Epiphyte metapopulation dynamics are explained by species traits, connectivity, and patch dynamics.
Victor Johansson1, Thomas Ranius, Tord Snäll
1Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, SE-750 07 Uppsala, Sweden. victor.johansson@slu.se
Ecology
|May 26, 2012
Summary
Metapopulation dynamics of lichens on trees depend on patch connectivity and species traits. Patch destruction, not local extinction, drives metapopulation dynamics for these sessile species.
Area of Science:
- Ecology
- Metapopulation Dynamics
- Landscape Ecology
Background:
- Patch dynamics significantly influence species colonization-extinction rates.
- Understanding metapopulation dynamics in sessile species within dynamic landscapes is crucial.
Purpose of the Study:
- To investigate metapopulation dynamics of epiphytic lichens on dynamic oak patches.
- To model colonization and extinction rates influenced by landscape and species traits.
Main Methods:
- Fitted a Bayesian incidence function model to snapshot data of five lichen species on 2083 oaks.
- Estimated patch suitability age and niche breadth for each species.
- Quantified local dispersal versus background deposition for long-distance dispersal.
Main Results:
- Colonization rates were low but increased with landscape connectivity.
- Species with wider niches and smaller propagules exhibited higher colonization rates.
- Extinction rates were primarily determined by patch destruction (tree fall), with negligible local extinctions.
Conclusions:
- Epiphyte metapopulation dynamics are characterized by slow colonization-extinction rates.
- Connectivity, species traits (niche breadth, propagule size), and patch dynamics are key drivers.
- Long-distance dispersal plays a significant role in epiphyte distribution.
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