| Model ID: | M00003 | ||||||
| Model Name: | PROSPECT-SAIL | ||||||
| Encoders: |
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| Key words: | Leaf, canopy, reflectance | ||||||
| Model Type: | Physical model | ||||||
| Latest Modified: | 2012/11/1 0:00:00 | ||||||
| Submission Date: | 2012/11/7 0:00:00 | ||||||
| Abstract: | PROSPECT model pioneered the simulation of directional–hemispherical reflectance and transmittance of various green monocotyledon and dicotyledon species at leaf level, as well as senescent leaves, over the solar spectrum from 400 nm to 2500 nm. It is based on the Allen et al. (1969) representation of the leaf as one or several absorbing plates with rough surfaces giving rise to isotropic scattering. | ||||||
| Equation: |
| 1 |
Name: cm
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Parameter type: double
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Physic Entity: Dry matter content.
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| 2 |
Name: cw
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Parameter type: double
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Physic Entity: Water content. Unit:g/cm2
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| 3 |
Name: cab
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Parameter type: double
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Physic Entity: Chlorophyll content. Unit: μg/cm2
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| 4 |
Name: N
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Parameter type: double
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Physic Entity: the number of compact layers specifying the average number of air/cell walls interfaces within the mesophyll
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| 5 |
Name: LAI
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Parameter type: double
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Physic Entity: Leaf area index
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| 6 |
Name: LIDF
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Parameter type: string
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Physic Entity: Leaf incline angle distribution function
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| 7 |
Name: Soil_refl
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Parameter type: bool
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Physic Entity: Reflectance of soil layer
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| 8 |
Name: Theta_S
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Parameter type: double
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Physic Entity: Zenith angle of solar light
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| 9 |
Name: Theta_V
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Parameter type: double
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Physic Entity: Zenith angle of view beam
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| 10 |
Name: Phi
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Parameter type: double
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Physic Entity: Relative azimuth angle between solar light and view beam
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| 11 |
Name: Sky_Ratio
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Parameter type: double
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Physic Entity: Ratio of diffuse light to total solar light
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| Title: | Inversion of the PROSPECT + SAIL canopy reflectance model from AVIRIS equivalent spectra: Theoretical study | ||||||
| Authors: |
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| Cited by: | Remote Sensing of Environment Volume 44, Issues 2–3, May–June 1993, Pages 281–292 | ||||||
| Abstract: | The potentials and limits of estimating canopy parameters are investigated using only a reflectance spectrum in the optical domain, and the PROSPECT + SAIL model. Simulations are performed on AVIRIS (Airborne Visible / Infrared Imaging Spectrometer) equivalent spectra, corrected for the atmospheric effects. It is established that this model is numerically invertible. The sensitivity analysis of reflectance spectral features to changes in the values of canopy parameters (leaf mesophyll structure N, chlorophyll a + b concentration Cab, water depth Cw, leaf area index, LAI, and average leaf inclination angle θ1) suggests that the accuracy of the inversion procedure needs some constraints. The Cab and Cw parameters, which describe the leaf physiological status, can be generally retrieved with a reasonable accuracy; it is somewhat difficult to estimate the canopy geometrical parameters (LAI and θ1) separately. Determining the fraction of absorbed photosynthetic active radiation (APAR) with parameters derived from the inversion procedure is discussed. |
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