3 - Estimation of the Plant Area Density
Plugin : LVOXNom de classe : LVOX3_StepComputePAD
Description
Step allowing the computation of the Plant Area Density (PAD) for a grid set.
The field "Attenuation coefficient estimators method" allows choosing between multiple computation methods :
Users can also set a threshold for the actual hits (N = Nt - Nb) in a voxel (ie. if a For more informations regarding the different methods used to compute the PAD, refer to the provided article.
The field "Attenuation coefficient estimators method" allows choosing between multiple computation methods :
- Contact Frequency : CF
- Beer-Lambert : BL
- Maximum Likelyhood Estimator : MLE
- Bias-Corrected Maximum Likelyhood Estimator : BCMLE
- Bias-Corrected Beer-Lambert (Equal path) : BCBL
- Bias-Corrected Beer-Lambert (Unequal path) : BC2BL
Users can also set a threshold for the actual hits (N = Nt - Nb) in a voxel (ie. if a For more informations regarding the different methods used to compute the PAD, refer to the provided article.
Paramètres
Step parameters:
- Attenuation coefficient estimators method: String with the following possible values =
- Contact Frequency : CF
- Beer-Lambert : BL
- Maximum Likelyhood Estimator : MLE
- Bias-Corrected Maximum Likelyhood Estimator : BCMLE
- Bias-Corrected Beer-Lambert (Equal path) : BCBL
- Bias-Corrected Beer-Lambert (Unequal path) : BC2BL
- Compute estimator for N larger than: integer default = 5
- Use relative threshold: booleandefault = false
- Create grids corresponding to summations: booleandefault = false
Données d'entrée
Structure des données d'entrée recherchées :
Result : SGrids
...
Group (Group)
Hits (3D grid LVOX)
Theoretical (3D grid LVOX)
Before (3D grid LVOX)
Result : SGrids
...
Group (Group)
Hits (3D grid LVOX
Theoretical (3D grid LVOX
Before (3D grid LVOX
Données de sortie
Group [Group]:
...
One or many of the follwing, given the "Attenuation coefficient estimators method" selected :
LVOX3_Grid3D [PAD-ContactFreq]
LVOX3_Grid3D [PAD-MLE]
LVOX3_Grid3D [PAD-BiasCorMLE]
LVOX3_Grid3D [PAD-BeerLamb]
LVOX3_Grid3D [PAD-BiasCorBeerLamb]
LVOX3_Grid3D [PAD-UnequalPathBeerLamb]
If "Create grids corresponding to summations" is checked, all of the following will be produced :
LVOX3_Grid3D [FreePath Sum]
LVOX3_Grid3D [Effective FreePath Sum]
LVOX3_Grid3D [Delta Sum]
LVOX3_Grid3D [Effective Delta Sum]
LVOX3_Grid3D [Effective Delta Square Sum]
LVOX3_Grid3D [1_zleDelta Effective Sum]
Références
Nguyen Van-Tho, Fournier Richard A., Côté Jean-François, Pimont François. 2022. Estimation of vertical plant area density from single return terrestrial laser scanning point clouds acquired in forest environments. Remote Sensing of Environment. https://www.sciencedirect.com/science/article/pii/S0034425722002292.