Kirschbaum, M.U.F. (2004). Direct and indirect climate-change effects on photosynthesis and transpiration. Plant Biology 6: 242-253.
Abstract. Climate
change affects plants in many different ways. Increasing CO2
concentration can increase photosynthetic rates which is especially pronounced
for C3 plants, at high temperatures and under water-limited
conditions. Increasing temperature also affects photosynthesis, but plants have
a considerable ability to adapt to their growth conditions and can function
under even extremely high temperatures, provided adequate water is available.
Temperature optima differ between species and growth conditions, and they are
higher in elevated atmospheric CO2.
With
increasing temperature, vapour pressure deficits of the air may increase, and
with that, the transpiration rate from plant canopies. However, if stomata
close in response to increasing CO2 concentration, or if there is a
reduction in the diurnal temperature range, then transpiration rates may even
decrease.
Soil
organic matter decomposition rates are likely to be stimulated by higher
temperatures so that nutrients can be more readily mineralised and made
available to plants, which is likely to increase photosynthetic carbon gain in
nutrient-limited systems. All the factors listed above interact strongly so
that for different combinations of increases in temperature and CO2
concentration, and for systems in different climatic regions and primarily
affected by water or nutrient limitations, photosynthesis must be expected to
respond differently to the same climatic changes.
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