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Updated: May 10, 2026
10:20
Linking Predation Risk, Herbivore Physiological Stress and Microbial Decomposition of Plant Litter
Published on: March 12, 2013
Trophic cascade alters ecosystem carbon exchange.
Michael S Strickland1, Dror Hawlena, Aspen Reese
1School of Forestry and Environmental Studies, Yale University, New Haven, CT 06511, USA. strick77@vt.edu
Summary
Predators enhance carbon fixation and retention in plants, even without direct consumption. This trophic cascade, driven by predator presence, significantly impacts ecosystem carbon dynamics and storage in terrestrial environments.
Area of Science:
- Ecology
- Biogeochemistry
- Ecosystem Dynamics
Background:
- Trophic cascades, indirect effects of carnivores on plants via herbivores, are widespread.
- Their impact on terrestrial carbon cycling remains largely unexplored.
Purpose of the Study:
- To investigate how trophic structure influences ecosystem carbon dynamics.
- To determine the role of predator presence in carbon cycling and retention.
Main Methods:
- Utilized a (13)C pulse-chase experiment in a meadow system.
- Manipulated the presence of herbivores and predators to observe effects.
Main Results:
- Predator presence enhanced carbon fixation by plants, even without changes in total biomass.
- Cascading effects slowed carbon loss via ecosystem respiration.
- Carbon allocation shifted to aboveground and belowground plant tissues.
- 1.4-fold more carbon was retained in plant biomass with predators present, driven by nonconsumptive (fear) effects on herbivores.
Conclusions:
- Predator presence, not just consumption, significantly influences carbon uptake, allocation, and retention in terrestrial ecosystems.
- Trophic interactions play a crucial role in regulating the terrestrial carbon cycle.
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