A process-based model to predict the effects of climatic change on leaf isoprene emission rates

M. J. Martin, C. M. Stirling, S. W. Humphries, S. P. Long

Research output: Contribution to journalArticle

Abstract

A process-based model was constructed around the current knowledge of the biochemical pathway of isoprene synthesis, with the objective of producing a new model of high mechanistic content to simulate the effects of environmental change on rates of isoprene emission, and thus enable the prediction of emission rates under future climates. The model was based on the three potentially limiting processes underlying isoprene synthesis: Pyruvate supply to provide the substrate of isoprene carbon, supply of adenosine triphosphate (ATP) for phosphorylation to dimethylallyl pyrophosphate (DMAPP), and the rate of isoprene synthesis from DMAPP, which was controlled by the temperature dependency of the enzyme isoprene synthase. Using mechanistic methods wherever possible, model simulations predicted the relative effects of changing photon flux density, carbon dioxide concentrations and temperature on leaf isoprene emission rates. The model was used to predict the interactive effects of elevated concentrations of carbon dioxide and temperature on rates of isoprene emission. Simulations indicated that the effects of carbon dioxide and temperature on isoprene emission rates were complicated by the interactive effects of two of the controlling rate-limiting processes in the synthesis of isoprene, namely phosphorylation rates and isoprene synthase activity. Under present concentrations of carbon dioxide and at photon flux density levels above ca. 500 μmol m(-2) s(-1) the controlling rate process is the temperature dependency of isoprene synthase. (C) 2000 Elsevier Science B.V.

Original languageEnglish (US)
Pages (from-to)161-174
Number of pages14
JournalEcological Modelling
Volume131
Issue number2-3
DOIs
StatePublished - Jul 1 2000

Keywords

  • Climate change
  • Elevated carbon dioxide
  • Isoprene emissions
  • Temperature

ASJC Scopus subject areas

  • Ecological Modeling

Fingerprint Dive into the research topics of 'A process-based model to predict the effects of climatic change on leaf isoprene emission rates'. Together they form a unique fingerprint.

  • Cite this