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Updated: Jun 5, 2026
04:35
Development of an Individual-Tree Basal Area Increment Model using a Linear Mixed-Effects Approach
Published on: July 3, 2020
Estimating gap lifetime and memory from a simple model of forest canopy dynamics.
Christopher Pagnutti1, Madhur Anand, Mohamed Azzouz
1Department of Applied Mathematics, University of Western Ontario, London, ON, Canada N6A 3K7. cpagnutt@uwo.ca
Journal of Theoretical Biology
|January 25, 2011
Summary
Tropical forest gap dynamics were modeled using Barro Colorado Island data. Large gaps have a lifetime under 50 years, with patterns persisting for centuries, impacting forest structure.
Area of Science:
- Ecology
- Forest Dynamics
- Tropical Ecosystems
Background:
- Forest gaps are crucial disturbance events, yet their dynamics remain poorly understood.
- Understanding gap formation and closure is key to comprehending forest spatial patterns and long-term structure.
Purpose of the Study:
- To predict long-term tropical forest gap dynamics using established models and Barro Colorado Island data.
- To define gap lifetime and investigate the influence of gap size on this metric.
- To analyze the spatial 'memory' within forest gap patterns.
Main Methods:
- Utilized previously developed ecological models to simulate tropical forest gap dynamics.
- Fitted models to Barro Colorado Island data by comparing discrete Fourier transforms.
- Defined gap lifetime and examined spatiotemporal correlations to assess pattern memory.
Main Results:
- Predicted a typical lifetime of less than 50 years for large tropical forest gaps.
- Found that large-gap lifetime exhibits a logarithmic divergence with increasing gap size.
- Identified a spatiotemporal correlation time of approximately 160 years, indicating significant pattern persistence.
Conclusions:
- Forest gap dynamics, particularly for large gaps, are characterized by predictable lifetimes and logarithmic scaling.
- The long correlation time suggests that current gap patterns have a lasting influence on the spatial structure of tropical forests.
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