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| Titel |
Can leaf net carbon gain acclimate to keep up with global warming? |
| VerfasserIn |
Giulia Vico, Stefano Manzoni, Danielle Way, Vaughan Hurry |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250129448
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| Publikation (Nr.) |
 EGU/EGU2016-9564.pdf |
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| Zusammenfassung |
| Plants are able to adjust their physiological activity to fluctuations and long-term changes in
their growing environment. Nevertheless, projected increases in temperature will occur with
unprecedented speed. Will global warming exceed the thermal acclimation capacity of leaves,
thus reducing net CO2 assimilation? Such a reduction in net CO2 assimilation rate (Anet) in
response to warming may deplete ecosystems’ net primary productivity, with global impacts
on the carbon cycling. Here we combine data on net photosynthetic thermal acclimation to
changes in temperature with a probabilistic description of leaf temperature variability. We
analytically obtain the probability distribution of the net CO2 assimilation rate as a function
of species-specific leaf traits and growing conditions. Using this approach, we study
the effects of mean leaf temperature and its variability on average Anet and the
frequency of occurrence of sub-optimal thermal conditions. To maximize the net CO2
assimilation in warmer conditions, the thermal optimum for Anet (Topt) must track the
growing temperature. Observations suggest that plants’ thermal acclimation capacity
is limited, so that growing temperatures cannot be tracked by the Topt. It is thus
likely that net CO2 assimilation rates will decline in the future. Furthermore, for set
leaf traits, large fluctuations in leaf temperature reduce average Anet and increase
the frequency of occurrence of sub-optimal conditions for net CO2 assimilation. |
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