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Community assembly: alternative stable states or alternative transient states?
Tadashi Fukami1, Mifuyu Nakajima
1Department of Biology, Stanford University, Stanford, CA 94305-5020, USA. fukamit@stanford.edu
Ecology Letters
|July 28, 2011
Summary
Historical contingency
Area of Science:
- Ecology
- Community Ecology
- Ecological Modeling
Background:
- Alternative stable states (ASS) are a dominant framework for understanding historical contingency in community assembly.
- However, many real-world communities exist in transient states due to disturbances, and the applicability of ASS predictions to these states is unclear.
Purpose of the Study:
- To investigate how historical contingency influences community assembly in both stable and transient states.
- To determine if the conditions for historical contingency differ between stable and transient states.
- To propose a conceptual shift in ecological research focus.
Main Methods:
- Utilized a simple mathematical model of plant community assembly.
- Analyzed the dynamics of community assembly under varying conditions.
Main Results:
- The conditions under which historical contingency affects community assembly differ significantly for stable versus transient states.
- Factors like mortality rate, environmental heterogeneity, and plant-soil feedback contribute differently to historical contingency as assembly progresses.
- Transient states can persist for extended periods relative to immigration and generation times.
Conclusions:
- A conceptual shift from alternative stable states to alternative transient states is needed for a comprehensive understanding of historical contingency in community assembly.
- This shift is crucial for accurately predicting and managing ecological communities, especially those subject to frequent disturbances.
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