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Title: Boreal conifers maintain carbon uptake with warming despite failure to track optimal temperatures
Abstract Warming shifts the thermal optimum of net photosynthesis (ToptA) to higher temperatures. However, our knowledge of this shift is mainly derived from seedlings grown in greenhouses under ambient atmospheric carbon dioxide (CO2) conditions. It is unclear whether shifts inToptAof field-grown trees will keep pace with the temperatures predicted for the 21stcentury under elevated atmospheric CO2concentrations. Here, using a whole-ecosystem warming controlled experiment under either ambient or elevated CO2levels, we show thatToptAof mature boreal conifers increased with warming. However, shifts inToptAdid not keep pace with warming asToptAonly increased by 0.26–0.35 °C per 1 °C of warming. Net photosynthetic rates estimated at the mean growth temperature increased with warming in elevated CO2spruce, while remaining constant in ambient CO2spruce and in both ambient CO2and elevated CO2tamarack with warming. Although shifts inToptAof these two species are insufficient to keep pace with warming, these boreal conifers can thermally acclimate photosynthesis to maintain carbon uptake in future air temperatures.  more » « less
Award ID(s):
2021898
PAR ID:
10508050
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Nature Portfolio
Date Published:
Journal Name:
Nature Communications
Volume:
14
Issue:
1
ISSN:
2041-1723
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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