Abstract
Plants in forest understories are subjected to light environments consisting of a very low background of diffuse light that is punctuated by often much brighter sunflecks lasting from a few seconds to several minutes. These sunflecks, although usually present for less than 10% of the time, typically contribute 10 to 80% of the photosynthetically active photon flux density (PFD) (Chazdon 1988). Therefore much of the photosynthesis of understory plants may occur under transiently changing light conditions that characterize sunflecks. The environmental and physiological controls on photosynthesis during transient light changes are not necessarily the same as those that determine photosynthetic performance under steady-state conditions. The shade-plant syndrome of understory plants has been widely studied but mostly in terms of the controls on steady-state photosynthetic characteristics. Until recently, relatively little attention has been given to the mechanisms regulating the use of sunflecks.
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Pearcy, R.W., Pfitsch, W.A. (1995). The Consequences of Sunflecks for Photosynthesis and Growth of Forest Understory Plants. In: Schulze, ED., Caldwell, M.M. (eds) Ecophysiology of Photosynthesis. Springer Study Edition, vol 100. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-79354-7_17
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DOI: https://doi.org/10.1007/978-3-642-79354-7_17
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