A modelling study of BRDF canopy and radiation regime for borealforests

摘要

This paper presents a new radiative transfer modelling approach,for retrieving information on forest structural characteristics andphotosynthetic activity, both directly through an accurate computationof 3D photosynthetically active radiation (PAR) regime, and indirectlywith the simulation of remote sensing measurements. The DART model wasused for investigating spectral behavior and PAR environment of borealforest in Canada. The main features of BRDF (bidirectional reflectancefactor distribution) anisotropy are clearly comparison between simulatedand (PARABOLA, CASI, POLDER) BRDFs stresses the potential of DART, butalso the importance and difficulty to use accurate field data.Differences in forest architectures induce distinct PAR transmission and3D absorbed PAR (APAR), and their influence on canopy photosynthesis isillustrated with the coupling of the DART model with a leaf model