%0 Research article
%T The mathematics of linked optimisation for water and nitrogen use in a canopy
%A Buckley, Thomas N.
%A Miller, Jeffrey M.
%A Farquhar, Graham D.
%D 2002
%J Silva Fennica
%V 36
%N 3
%R doi:10.14214/sf.531
%U https://silvafennica.fi/article/531
%X We develop, and discuss the implementation of, a mathematical framework  for inferring optimal patterns of water and nitrogen use. Our analysis  is limited to a time scale of one day and a spatial scale consisting of  the green canopy of one plant, and we assume that this canopy has fixed  quantities of nitrogen and water available for use in photosynthesis.  The efficiencies of water and nitrogen use, and the interactions between  the two, are strongly affected by physiological and physical properties  that can be modeled in different ways. The thrust of this study is  therefore to discuss these properties and how they affect the  efficiencies of nitrogen and water use, and to demonstrate,  qualitatively, the effects of different model assumptions on inferred  optimal strategies. Preliminary simulations suggest that the linked  optimisation of nitrogen and water use is particularly sensitive to the  level of detail in canopy light penetration models (e.g., whether sunlit  and shaded fractions are pooled or considered independently), and to  assumptions regarding nitrogen and irradiance gradients within leaves  (which determine how whole-leaf potential electron transport rate is  calculated from leaf nitrogen content and incident irradiance).