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Updated: Jul 8, 2026
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Linking Predation Risk, Herbivore Physiological Stress and Microbial Decomposition of Plant Litter
Published on: March 12, 2013
Predators accelerate nutrient cycling in a bromeliad ecosystem.
Jacqueline T Ngai1, Diane S Srivastava
1Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada. ngai@zoology.ubc.ca
Science (New York, N.Y.)
|November 11, 2006
Summary
Predators boost nutrient cycling by preventing prey from leaving their environment. This unexpected finding reveals how predator loss can disrupt ecosystems and nutrient flow.
Area of Science:
- Ecology
- Ecosystem Functioning
- Nutrient Cycling
Background:
- Ecological theory posits predators reduce prey abundance or activity, impacting nutrient cycling.
- The role of predators in nutrient export via prey emigration has been overlooked.
- Bromeliads provide a model system for studying predator-detritivore-detritus food chains.
Purpose of the Study:
- To investigate the impact of predators on nutrient cycling in bromeliad ecosystems.
- To identify novel mechanisms by which predators influence ecosystem functioning.
- To assess the consequences of predator loss on nutrient dynamics.
Main Methods:
- Utilized a predator-detritivore-detritus food chain within bromeliads.
- Monitored nutrient cycling, specifically nitrogen uptake and export.
- Quantified the effects of predation on detritivore emergence and emigration.
Main Results:
- Predation on detritivores decreased detritivore emigration, reducing nitrogen export from bromeliads.
- Contrary to conventional theory, predation increased detrital nitrogen uptake by the host plant.
- Detritivores benefited their host plant only in the presence of predators.
Conclusions:
- Predators can enhance nutrient cycling by reducing prey-mediated nutrient export.
- Predator loss can lead to significant and unforeseen alterations in ecosystem functioning.
- This study reveals a new mechanism of predator influence on nutrient dynamics.
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