TY - JOUR
T1 - Insect herbivory in an intact forest understory under experimental CO 2 enrichment
AU - Hamilton, Jason G.
AU - Zangerl, Arthur R.
AU - Berenbaum, May R.
AU - Pippen, Jeffrey
AU - Aldea, Mihai
AU - DeLucia, Evan H.
N1 - Funding Information:
Acknowledgements We gratefully acknowledge the help of Susanne Aref with statistical analysis. Nitrogen and carbon analyses were performed by the Stable Isotope/Soil Biology Laboratory of the University of Georgia Institute of Ecology. Pete Ficarello, Grace Lee, Shireen Lum, Jennie Wise helped with chemical analyses. Jon Fisher, Ann Singsaas, Isabelle Zamfirescu, Eric Huang, and Itay Pashtan helped with acquisition and analysis of the digital images. David Stephan and Tom Creswell of the Plant Disease and Insect Clinic of North Carolina Cooperative Extension Service provided assistance with insect identification. We wish to acknowledge the assistance of Andrew Palmiotti and Brookhaven National Laboratory, which manages the FACTS−1 facility under U.S. Department of Energy contract No. DE-AC02–98CH10886. Funding for this work was provided in part by the University of Illinois Critical Research Initiative, Ithaca College, and the National Science Foundation (IBN 0236053).
PY - 2004/3
Y1 - 2004/3
N2 - Human-induced increases in atmospheric CO2 concentration have the potential to alter the chemical composition of plant tissue, and thereby affect the amount of tissue consumed by herbivorous arthropods. At the Duke Forest free-air concentration enrichment (FACE) facility in North Carolina (FACTS-1 research facility), we measured the amount of leaf tissue damaged by insects and other herbivorous arthropods during two growing seasons in a deciduous forest understory continuously exposed to ambient (360 μl l -1) and elevated (∼560 μl l-1) CO2 conditions. In 1999, there was a significant interaction between CO2 and species such that winged elm (Ulmus alata) showed lower herbivory in elevated CO2 plots, whereas red maple (Acer rubra) and sweetgum (Liquidambar styraciflua) did not. In 2000, our results did not achieve statistical significance but the magnitude of the result was consistent with the 1999 results. In 1999 and 2000, we found a decline (10-46%) in community-level herbivory in elevated CO2 plots driven primarily by reductions in herbivory on elm. The major contribution to total leaf damage was from missing tissue (66% of the damaged tissue), with galls, skeletonized, and discolored tissue making smaller contributions. It is unclear whether the decline in leaf damage is a result of altered insect populations, altered feeding, or a combination. We were not able to quantify insect populations, and our measurements did not resolve an effect of elevated CO2 on leaf chemical composition (total nitrogen, carbon, C/N, sugars, phenolics, starch). Despite predictions from a large number of single-species studies that herbivory may increase under elevated CO2, we have found a decrease in herbivory in a naturally established forest understory exposed to a full suite of insect herbivores and their predators.
AB - Human-induced increases in atmospheric CO2 concentration have the potential to alter the chemical composition of plant tissue, and thereby affect the amount of tissue consumed by herbivorous arthropods. At the Duke Forest free-air concentration enrichment (FACE) facility in North Carolina (FACTS-1 research facility), we measured the amount of leaf tissue damaged by insects and other herbivorous arthropods during two growing seasons in a deciduous forest understory continuously exposed to ambient (360 μl l -1) and elevated (∼560 μl l-1) CO2 conditions. In 1999, there was a significant interaction between CO2 and species such that winged elm (Ulmus alata) showed lower herbivory in elevated CO2 plots, whereas red maple (Acer rubra) and sweetgum (Liquidambar styraciflua) did not. In 2000, our results did not achieve statistical significance but the magnitude of the result was consistent with the 1999 results. In 1999 and 2000, we found a decline (10-46%) in community-level herbivory in elevated CO2 plots driven primarily by reductions in herbivory on elm. The major contribution to total leaf damage was from missing tissue (66% of the damaged tissue), with galls, skeletonized, and discolored tissue making smaller contributions. It is unclear whether the decline in leaf damage is a result of altered insect populations, altered feeding, or a combination. We were not able to quantify insect populations, and our measurements did not resolve an effect of elevated CO2 on leaf chemical composition (total nitrogen, carbon, C/N, sugars, phenolics, starch). Despite predictions from a large number of single-species studies that herbivory may increase under elevated CO2, we have found a decrease in herbivory in a naturally established forest understory exposed to a full suite of insect herbivores and their predators.
KW - Arthropod herbivores
KW - Elevated carbon dioxide
KW - FACE
KW - Folivory
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U2 - 10.1007/s00442-003-1463-5
DO - 10.1007/s00442-003-1463-5
M3 - Article
C2 - 14714173
AN - SCOPUS:1642304020
SN - 0029-8549
VL - 138
SP - 566
EP - 573
JO - Oecologia
JF - Oecologia
IS - 4
ER -