The paper overviewes the available radiation models of a leaf. A new idea of the leaf optical model is proposed as a multiphase system containing three aggregate ensembles of particles, which differ greatly in their microphysical and optical characteristics. The basis for the proposed model is the solution of the problem of reconstruction of the function of the particle size distribution from the leaf absorption experimental spectrum. On the basis of the developed by the authors microphysical model of a plant leaf the spectra of the optical radiation reflection and transmission were calculated in the range from 400 to 800 nm for different relative concentration of luminous absorbing pigments (chlorophyll a,b and carotins) as well as for different leaf thicknesses. The optical radiation propagation was modeled performed by the Monte-Carlo stochastic method. The results of modeling are in good agreement with the known experimental spectra.
transfer theory; Monte-Carlo method; optical model