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Scaling up the functional response for spatially heterogeneous systems.
Göran Englund1, Kjell Leonardsson
1Department of Ecology and Environmental Science & Umeå Marine Sciences Centre, Umeå University, SE-901 87 Umeå, Sweden. goran.englund@emg.umu.se
Ecology Letters
|February 26, 2008
Summary
Scale transition theory accurately predicts regional population dynamics using local data. Validating lab results with field observations is crucial for reliable ecological predictions in heterogeneous systems.
Area of Science:
- Ecology
- Population Dynamics
- Theoretical Ecology
Background:
- Scale transition theory provides a framework for predicting population dynamics across spatial scales.
- Understanding regional population dynamics requires integrating local processes and spatial heterogeneity.
- Benthic predator-prey systems are key models for studying ecological interactions.
Purpose of the Study:
- To estimate regional scale functional responses for a benthic predator-prey system in the Baltic Sea using scale transition theory.
- To compare functional responses derived from laboratory experiments versus local-scale field data.
- To assess the influence of spatial heterogeneity and scale on predator-prey interactions.
Main Methods:
- Applied scale transition theory to a Baltic Sea benthic predator-prey system.
- Utilized functional responses from laboratory experiments and field stomach content analysis.
- Measured prey densities at both local (0.1 m^2) and regional (300 km^2) scales.
- Validated predictions with regional-scale consumption observations.
Main Results:
- Laboratory data overestimated consumption at high prey densities compared to field observations.
- Predictions based on local-scale data closely matched regional-scale consumption.
- Regional functional responses differed for increasing and decreasing prey densities due to oscillatory dynamics.
- Predator and prey densities, and their covariance, exhibited dynamic oscillations.
Conclusions:
- Validating laboratory data with small-scale field observations is essential for ecological accuracy.
- Scale transition theory is a powerful tool for scaling up ecological process functions in heterogeneous environments.
- Spatial scale significantly influences the estimation of predator-prey functional responses.
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