48
IRUS Total
Downloads
  Altmetric

A unifying conceptual model for the environmental responses of isoprene emissions from plants

Title: A unifying conceptual model for the environmental responses of isoprene emissions from plants
Authors: Morfopoulos, C
Prentice, IC
Keenan, TF
Friedlingstein, P
Medlyn, BE
Penuelas, J
Possell, M
Item Type: Journal Article
Abstract: Background and Aims Isoprene is the most important volatile organic compound emitted by land plants in terms of abundance and environmental effects. Controls on isoprene emission rates include light, temperature, water supply and CO 2 concentration. A need to quantify these controls has long been recognized. There are already models that give realistic results, but they are complex, highly empirical and require separate responses to different drivers. This study sets out to find a simpler, unifying principle. † Methods A simple model is presented based on the idea of balancing demands for reducing power (derived from photosynthetic electron transport) in primary metabolism versus the secondary pathway that leads to the synthesis of isoprene. This model’s ability to account for key features in a variety of experimental data sets is assessed. † Key results The model simultaneously predicts the fundamental responses observed in short-term experiments, namely: (1) the decoupling between carbon assimilation and isoprene emission; (2) a continued increase in isoprene emission with photosynthetically active radiation (PAR) at high PAR, after carbon assimilation has saturated; (3) a maximum of isoprene emission at low internal CO 2 concentration ( c i ) and an asymptotic decline thereafter with in- creasing c i ; (4) maintenance of high isoprene emissions when carbon assimilation is restricted by drought; and (5) a temperature optimum higher than that of photosynthesis, but lower than that of isoprene synthase activity. † Conclusions A simple model was used to test the hypothesisthat reducing poweravailable to the synthesis pathway for isoprene varies according to the extent to which the needs of carbon assimilation are satisfied. Despite its simpli- city the model explains much in terms of the observed response of isoprene to external drivers as well asthe observed decoupling between carbon assimilation and isoprene emission. The concept has the potential to improve global- scale modelling of vegetation isoprene emission.
Issue Date: 19-Sep-2013
Date of Acceptance: 9-Jul-2013
URI: http://hdl.handle.net/10044/1/56725
DOI: https://dx.doi.org/10.1093/aob/mct206
ISSN: 0305-7364
Publisher: Oxford University Press
Start Page: 1223
End Page: 1238
Journal / Book Title: ANNALS OF BOTANY
Volume: 112
Issue: 7
Copyright Statement: © The Author 2013. Published by Oxford University Press on behalf of the Annals of Botany Company. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
Keywords: Science & Technology
Life Sciences & Biomedicine
Plant Sciences
Isoprene
modelling
electron transport
photosynthesis
temperature
carbon dioxide
isoprene emission
volatile organic compounds
ATMOSPHERIC CO2 CONCENTRATION
VOLATILE ORGANIC-COMPOUNDS
SYNTHASE ACTIVITY
MONOTERPENE EMISSION
QUERCUS-ROBUR
TEMPERATURE-ACCLIMATION
TROPOSPHERIC CHEMISTRY
BIOCHEMICAL-MODEL
NITRATE REDUCTASE
BIOGENIC ISOPRENE
Butadienes
Carbon Dioxide
Electrons
Environment
Hemiterpenes
Light
Models, Biological
NADP
Pentanes
Photosynthesis
Plants
Temperature
0607 Plant Biology
0602 Ecology
Plant Biology & Botany
Publication Status: Published
Appears in Collections:Department of Life Sciences
Grantham Institute for Climate Change
Faculty of Natural Sciences