A semidiscrete model for the scattering of light by vegetation

An advanced bidirectional reflectance factor model is developed to account for the architectural effects exhibited by homogeneous vegetation canopies for the first orders of light scattering. The characterization of the canopy allows the simulation of the relevant scattering processes as a function of the number, size, and orientation of the leaves, as well as the total height of the canopy. A turbid medium approach is used to represent the contribution to the total reflectance due to the light scattering at orders higher than 1. This model therefore incorporates two previously separate approaches to the problem of describing light scattering in plant canopies and enhances existing models relying on parameterized formulae to account for the hot spot effect in the extinction coefficient. Simulation results using this model compare quite favorably with those produced with a Monte Carlo ray-tracing model for a variety of vegetation cases. The semidiscrete model is also inverted against a well-documented data set of bidirectional reflectance factors taken over a soybean canopy. It is shown that the inversion of the model against a small subset of these measurements leads to reasonable values for the retrieved canopy parameters. These values are used in a direct mode to simulate the bidirectional reflectance factors for solar and viewing conditions significantly different from those available in the subset of soybean data and compared with the full set of actual measurements.

[1]  M. Monsi.  Uber den Lichtfaktor in den Pflanzengesellschaften und seine Bedeutung fur die Stoffproduktion , 1953 .

[2]  T. Nilson.  A theoretical analysis of the frequency of gaps in plant stands , 1971 .

[3]  K. Kriebel,et al.  Measured spectral bidirectional reflection properties of four vegetated surfaces. , 1978, Applied optics.

[4]  N. Bunnik.  The multispectral reflectance of shortwave radiation by agricultural crops in relation with their morphological and optical properties , 1978 .

[5]  B. Hapke.  Bidirectional reflectance spectroscopy: 1. Theory , 1981 .

[6]  J. Ross.  The radiation regime and architecture of plant stands , 1981, Tasks for vegetation sciences 3.

[7]  J. M. Norman.  Radiative Transfer in Vegetation , 1982 .

[8]  P. Deschamps,et al.  Influence of the atmosphere on space measurements of directional properties. , 1983, Applied optics.

[9]  L. Biehl,et al.  Soybean canopy reflectance modeling data sets , 1984 .

[10]  B. Hapke.  Bidirectional reflectance spectroscopy , 1984 .

[11]  D. Kimes.  Modeling the directional reflectance from complete homogeneous vegetation canopies with various leaf-orientation distributions , 1984 .

[12]  N. Goel,et al.  Simple Beta Distribution Representation of Leaf Orientation in Vegetation Canopies1 , 1984 .

[13]  V. Vanderbilt,et al.  Plant Canopy Specular Reflectance Model , 1985, IEEE Transactions on Geoscience and Remote Sensing.

[14]  M. Verstraete.  Radiation transfer in plant canopies - Transmission of direct solar radiation and the role of leaf orientation , 1987 .

[15]  A. Marshak,et al.  Calculation of canopy bidirectional reflectance using the Monte Carlo method , 1988 .

[16]  R. Myneni,et al.  Radiative transfer in vegetation canopies with anisotropic scattering , 1988 .

[17]  R. Dickinson,et al.  A physical model for predicting bidirectional reflectances over bare soil , 1989 .

[18]  R. Myneni,et al.  A review on the theory of photon transport in leaf canopies , 1989 .

[19]  T. Takakura,et al.  Influence of CO2 Enrichment in Jar Fermentor Culture on the pH of Culture Media , 1989 .

[20]  A. Kuusk,et al.  A reflectance model for the homogeneous plant canopy and its inversion , 1989 .

[21]  A. Marshak.  The effect of the hot spot on the transport equation in plant canopies , 1989 .

[22]  R. Dickinson,et al.  A physical model of the bidirectional reflectance of vegetation canopies: 2. Inversion and validation , 1990 .

[23]  B. Pinty,et al.  A physical model of the bidirectional reflectance of vegetation canopies , 1990 .

[24]  A. Kuusk.  The Hot Spot Effect in Plant Canopy Reflectance , 1991 .

[25]  A. Strahler,et al.  A hotspot model for leaf canopies , 1991 .

[26]  Y. Knyazikhin,et al.  Transport theory for a leaf canopy of finite-dimensional scattering centers , 1991 .

[27]  Y. Knyazikhin,et al.  Discrete Ordinates Method for Photon Transport in Leaf Canopies , 1991 .

[28]  Y. Knyazikhin,et al.  Interaction of photons in a canopy of finite-dimensional leaves , 1992 .

[29]  Alan H. Strahler,et al.  Calculation of the angular radiance distribution for a coupled atmosphere and canopy , 1993, IEEE Trans. Geosci. Remote. Sens..

[30]  G. Dedieu,et al.  SMAC: a simplified method for the atmospheric correction of satellite measurements in the solar spectrum , 1994 .

[31]  J. Iaquinta.  Champs de rayonnement emergeant des surfaces terrestres : modelisation et inversion dans le cas de milieux optiquement finis et couples avec une couche atmospherique , 1995 .

[32]  Stéphane Jacquemoud,et al.  Modeling plant leaf bidirectional reflectance and transmittance with a 3-D ray tracing approach , 1995, 1995 International Geoscience and Remote Sensing Symposium, IGARSS '95. Quantitative Remote Sensing for Science and Applications.

[33]  Michel M. Verstraete,et al.  Evaluation of the capability of BRDF models to retrieve structural information on the observed target as described by a three-dimensional ray tracing code , 1995, Remote Sensing.

[34]  B. Pinty,et al.  Adaptation of a bidirectional reflectance model including the hot‐spot to an optically thin canopy , 1997 .

[35]  Nadine Gobron,et al.  Theoretical limits to the estimation of the leaf area index on the basis of visible and near-infrared remote sensing data , 1997, IEEE Trans. Geosci. Remote. Sens..

[36]  B. Pinty,et al.  Modeling the Scattering of Light by Homogeneous Vegetation in Optical Remote Sensing , 1998 .