The photosynthesis is defined by a pair of nested quadratic equations:

M flux determined by the Rubisco and light limited capacities

${\Phi}$ fixed equal to 0.83

${\beta}$ fixed equal to 0.93

M smaller root of

\begin{equation}
{\Phi \cdot M^{{2}}-M\cdot (V_{{c}}(l)+\alpha \cdot Q)+V_{{c}}(l)\cdot \alpha \cdot Q=0}
\end{equation}
Ci(l) (leaf\_ci) global variable declared in diffuco module

W smaller root of

\begin{equation}
{\beta \cdot W^{{2}}-W\cdot (M+k_{{T}}\cdot C_{{i}}(l)\cdot {10}^{{-6}})+M\cdot k_{{T}}\cdot C_{{i}}(l)\cdot {10}^{{-6}}=0}
\end{equation}
${\alpha}$ quantum efficiency

\begin{equation}
{\alpha \cdot Q=0{.}{092}\cdot 2{.}3\cdot {{SWdown}}\cdot k\cdot e^{{-k\cdot {{LAI}}(l)}}}
\end{equation}

\begin{equation}
{M=\frac{V_{{c}}(l)+\alpha \cdot Q-\sqrt{(V_{{c}}(l)+\alpha \cdot Q)^{{2}}-4\cdot \Phi \cdot V_{{c}}(l)\cdot \alpha \cdot Q}}{2\cdot \Phi }}
\end{equation}

\begin{equation}
{W=\frac{M+k_{{T}}\cdot C_{{i}}(l){.}{10}^{{-6}}-\sqrt{(M+k_{{T}}\cdot C_{{i}}(l){.}{10}^{{-6}})^{{2}}-4\cdot \beta \cdot M\cdot k_{{T}}\cdot C_{{i}}(l){.}{10}^{{-6}}}}{2\cdot \beta }}
\end{equation}
\begin{equation}
{A=W-R_{{T}}}
\end{equation}
