Trophic cascade alters ecosystem carbon exchange

Michael S. Strickland, Dror Hawlena, Aspen Reese, Mark A. Bradford, Oswald J. Schmitz

Research output: Contribution to journalArticlepeer-review

73 Scopus citations

Abstract

Trophic cascades - the indirect effects of carnivores on plants mediated by herbivores - are common across ecosystems, but their influence on biogeochemical cycles, particularly the terrestrial carbon cycle, are largely unexplored. Here, using a 13C pulse-chase experiment, we demonstrate how trophic structure influences ecosystem carbon dynamics in a meadow system. By manipulating the presence of herbivores and predators, we show that even without an initial change in total plant or herbivore biomass, the cascading effects of predators in this system begin to affect carbon cycling through enhanced carbon fixation by plants. Prolonged cascading effects on plant biomass lead to slowing of carbon loss via ecosystem respiration and reallocation of carbon among plant aboveground and belowground tissues. Consequently, up to 1.4-fold more carbon is retained in plant biomass when carnivores are present compared with when they are absent, owing primarily to greater carbon storage in grass and belowground plant biomass driven largely by predator nonconsumptive (fear) effects on herbivores. Our data highlight the influence that the mere presence of predators, as opposed to direct consumption of herbivores, can have on carbon uptake, allocation, and retention in terrestrial ecosystems.

Original languageEnglish
Pages (from-to)11035-11038
Number of pages4
JournalProceedings of the National Academy of Sciences of the United States of America
Volume110
Issue number27
DOIs
StatePublished - 2 Jul 2013
Externally publishedYes

Keywords

  • Animal-mediated carbon cycling
  • Carbon retention
  • Carbon tracer experiment
  • Experimental ecosystem ecology

ASJC Scopus subject areas

  • General

Fingerprint

Dive into the research topics of 'Trophic cascade alters ecosystem carbon exchange'. Together they form a unique fingerprint.

Cite this