2.6 | Stomatal limitation 
The degree of stomatal limitation of net photosynthesis (l ) was calculated following Farquhar & Sharkey (1982). In this approach observed photosynthesis is compared to what would be if stomatal conductance (gs) would be infinite:
\(l\ =1\ -\ \frac{\text{P\ }_{\text{Observed}}}{P_{\left(\ g_{s}\right)}}\)Eqn.
P(infinite gs) is calculated from the FvCB model by setting Ci in Eqn to equal Ca, the observed CO2 concentration in the cuvette:
\(V_{\text{CMax}}=\frac{P_{\text{gross}}\times\ \left(C_{i}\ +\text{\ K}_{c}\right)}{C_{i}\ -\text{\ Γ}^{*}}\)Eqn.
Pgross equals light-saturated photosynthesis plus RLight, where RLight is assumed to be equal to 1.5% of VCMax; Kc is the Michaelis–Menten constant of Rubisco activity for CO2taken from Bernacchi et al. (2001).