Ecological stoichiometry and nutrient partitioning in two insect herbivores responsible for large-scale forest disturbance in the Fennoscandian subarctic

Research output: Contribution to journalArticle

Abstract

1. Outbreaks of herbivorous insects can have large impacts on regional soil carbon (C) storage and nutrient cycling. In northernmost Europe, population outbreaks of several geometrid moth species regularly cause large-scale defoliation in subarctic birch forests. An improved understanding is required of how leaf C and nutrients are processed after ingestion by herbivores and what this means for the quantity and quality of different materials produced (frass, bodies). 2. In this study, larvae of two geometrid species responsible for major outbreaks (Epirrita autumnata and Operophtera brumata) were raised on exclusive diets of Betula pubescens var. czerepanovii (N. I. Orlova) Hämet Ahti and two other abundant understorey species (Betula nana, Vaccinium myrtillus). The quantities of C, nitrogen (N) and phosphorus (P) ingested and allocated to frass, bodies and (in the case of C) respired were recorded. 3. Overall, 23%, 70% and 48% of ingested C, N and P were allocated to bodies, respectively, rather than frass and (in the case of C) respiration. Operophtera brumata consistently maintained more constant body stoichiometric ratios of C, N and P than did E. autumnata, across the wide variation in physico-chemical properties of plant diet supplied. 4. These observed differences and similarities on C and nutrient processing may improve researchers' ability to predict the amount and stoichiometry of frass and bodies generated after geometrid outbreaks.

Details

Authors
Organisations
External organisations
  • Umeå University
  • Norwegian Institute for Nature Research
  • UiT The Arctic University of Norway, Tromsø
  • Lund University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Ecology
  • Zoology

Keywords

  • Consumer-driven nutrient recycling, ecological stoichiometry, geometrid moth, homeostasis, stable isotope, subarctic birch forest
Original languageEnglish
Pages (from-to)118-128
JournalEcological Entomology
Volume44
Issue number1
Early online date2018 Oct 4
Publication statusPublished - 2019 Feb
Publication categoryResearch
Peer-reviewedYes