Acclimation of photosynthesis to light and canopy nitrogen distribution: an interpretation.
OBJECTIVE
Acclimation of photosynthesis to light and its connection with canopy nitrogen (N) distribution are considered. An interpretation of a proportionality between light-saturated photosynthesis and local averaged leaf irradiance is proposed by means of a simple model.


METHODS
The model assumes (a) local irradiance drives synthesis of photosynthetic protein from metabolic N; (b) photosynthetic N is slowly degraded over approx. 5-7 d; (c) metabolic N is equally available through the canopy.


CONCLUSIONS
The kinetics of acclimation at different light levels may provide a way of parameterizing and testing the model. The model provides a rationale for the proportionality assumption mentioned above, which, while it is consistent with much experimental work, is valuable because it allows canopy photosynthesis to be calculated analytically.
Centre for Ecology & Hydrology, Bush Estate, Penicuik, Midlothian EH26 0QB, UK. johnthornley@care4free.net
J H M
JH
Thornley
D000064:Acclimatization / Q000502:physiology* / Q000528:radiation effects; D008027:Light; D008954:Models, Biological; D009584:Nitrogen / Q000378:metabolism*; D010788:Photosynthesis / Q000502:physiology* / Q000528:radiation effects; D018515:Plant Leaves / Q000502:physiology* / Q000528:radiation effects; D013997:Time Factors
D009584:Nitrogen