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A Biomass Flow Approach to Population Models and Food Webs
1Dept. Environmental Science, Policy and Management, University of California at Berkeley, CA 94720-3114, USA, getz@nature.berkeley.edu , 1-510-642-8745.
Natural Resource Modeling
|October 1, 2016
Summary
This study introduces a new biomass transformation formulation (BTW) for food web dynamics, correcting limitations in traditional models. BTW unifies the treatment of live and dead biomass, offering a more comprehensive approach to ecological interactions.
Area of Science:
- Ecology
- Mathematical Biology
- Population Dynamics
Background:
- Traditional Lotka-Volterra models dominate food web dynamics but lack trophic-level independence and inertial processes.
- Existing models struggle with species acting as both prey and predator and do not fully account for environmental fluctuations.
Purpose of the Study:
- To present a novel biomass transformation formulation (BTW) that addresses limitations in current food web modeling paradigms.
- To provide a unified framework for biomass transformation, incorporating both live and dead components of all species.
Main Methods:
- Developed a new approach, the biomass transformation formulation (BTW), building upon metaphysiological growth modeling.
- Formulated BTW using a three-variable differential equation for each species: live biomass, dead biomass, and deficit-stress.
Main Results:
- The BTW framework allows for a unified treatment of diverse feeding strategies, including carnivores, carcasivores, herbivores, detritivores, scavengers, and parasites.
- Demonstrated the application of BTW to analyze two-species competition in variable environments.
Conclusions:
- The BTW paradigm offers a more coherent and comprehensive method for modeling food web dynamics.
- This approach enhances understanding of population responses to fluctuating environments and can be applied to complex food webs including parasites and pathogens.
Keywords:
HollingLotka-Volterracompetitionconsumer-resourcefunctional responsehost-parasitepathogen dynamicsplant-herbivoreprey-predatorscavengertrophic modelsMore Related Videos
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