Light — vegetation interaction: a new stochastic approach for description and classification

Abstract The radiation regime of the vegetation canopy is influenced by the optical properties and spatial distribution of the phytoelements. Macroscopic fluctuations of the geometrical structure and overlapping of the phytoelements result in increased transmittance of the vegetation canopy. A theoretical method based on the averaged equations for the radiation field statistical parameters can be used to describe the disturbed radiation field pattern in the vegetation canopy with fluctuating optical properties. Within the scope of this method random fluctuations of the volumetric optical parameters are expressed through the statistical moments of the scattering phase function, angular distribution function and area density of the phytoelements. The model of the radiation regime was used to calculate the contribution of the stochastic component to downward and upward radiation fluxes and to follow the changes of the light spectrum with depth owing to the fluctuations of the geometrical structure of the vegetation canopy.