Plant and Soil

, Volume 399, Issue 1–2, pp 29–39

Precipitation, not CO2 enrichment, drives insect herbivore frass deposition and subsequent nutrient dynamics in a mature Eucalyptus woodland

  • Andrew N. Gherlenda
  • Kristine Y. Crous
  • Ben D. Moore
  • Anthony M. Haigh
  • Scott N. Johnson
  • Markus Riegler
Regular Article

DOI: 10.1007/s11104-015-2683-2

Cite this article as:
Gherlenda, A.N., Crous, K.Y., Moore, B.D. et al. Plant Soil (2016) 399: 29. doi:10.1007/s11104-015-2683-2
  • 325 Downloads

Abstract

Background and aims

Herbivorous insects are important nutrient cyclers that produce nutrient-rich frass. The impact of elevated atmospheric [CO2] on insect-mediated nutrient cycling, and its potential interaction with precipitation and temperature, is poorly understood and rarely quantified. We tested these climatic effects on frass deposition in a nutrient-limited mature woodland.

Methods

Frass deposition by leaf-chewing insects and its chemical composition was quantified monthly over the first 2 years at the Eucalyptus free-air CO2 enrichment experiment and contrasted with leaf nitrogen concentration, rainfall and temperature.

Results

Leaf-chewing insects produced yearly between 160 and 270 kg ha−1 of frass depositing 2 to 4 kg ha−1 of nitrogen. Frass quantity and quality were influenced by rainfall and average maximum temperatures. In contrast, elevated CO2 did not impact nitrogen concentrations in fully expanded leaves and frass deposition to the woodland floor.

Conclusions

Two years of elevated CO2 did not alter nutrient transfer by leaf-chewing insects. This may be due to the low nutrient status of this ecosystem, duration of CO2 fumigation or climatic conditions. However, rainfall co-occurring with seasonally higher temperatures exerted strong effects on nutrient cycling, potentially through shifts in leaf phenology with consequences for insect population dynamics and insect-mediated nutrient transfer.

Keywords

Climate change Eucalypt EucFACE Nutrient cycling Insects 

Supplementary material

11104_2015_2683_MOESM1_ESM.docx (447 kb)
ESM 1(DOCX 446 kb)

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Andrew N. Gherlenda
    • 1
  • Kristine Y. Crous
    • 1
  • Ben D. Moore
    • 1
  • Anthony M. Haigh
    • 2
  • Scott N. Johnson
    • 1
  • Markus Riegler
    • 1
  1. 1.Hawkesbury Institute for the EnvironmentWestern Sydney UniversityPenrithAustralia
  2. 2.School of Science and HealthWestern Sydney UniversityPenrithAustralia

Personalised recommendations