crown_diameterheight_ratio_qsm: Crown diameter height ratio TreeQSM

In lmterryn/ITSMe: Individual Tree Structural Metrics

Crown diameter height ratio TreeQSM

Description

Calculates the ratio between the crown diameter and the crown height from a TreeQSM (Akerblom et al., 2017 & Terryn et al., 2020).

Usage

crown_diameterheight_ratio_qsm(treedata, cylinder, pc = NA, dtm = NA, r = 5)

Arguments

treedata	Treedata field of a TreeQSM that is returned by read_tree_qsm.
cylinder	Cylinder field of a TreeQSM that is returned by read_tree_qsm.
pc	The tree point cloud as a data.frame with columns X,Y,Z. Output of read_tree_pc. Default is NA and indicates no tree point cloud is available.
dtm	The digital terrain model as a data.frame with columns X,Y,Z (default = NA). If the digital terrain model is in the same format as a point cloud it can also be read with read_tree_pc. only relevant when a point cloud is provided.
r	Numeric value (default=5) r which determines the range taken for the dtm. Should be at least the resolution of the dtm. Only relevant when a dtm is provided.

Details

The crown diameter is the maximum radii of the vertical bin radius estimates that are calculated with vertical_bin_radii_qsm. The crown height is the vertical distance between the highest and the lowest crown cylinder and is obtained from crown_height_qsm multiplied with the tree_height.

Value

The ratio of the crown diameter and crown height.

References

Akerblom, M., Raumonen, P., Makipaa, R., & Kaasalainen, M. (2017). Automatic tree species recognition with quantitative structure models. Remote Sensing of Environment, 191, 1-12.

Terryn, L., Calders, K., Disney, M., Origo, N., Malhi, Y., Newnham, G., ... & Verbeeck, H. (2020). Tree species classification using structural features derived from terrestrial laser scanning. ISPRS Journal of Photogrammetry and Remote Sensing, 168, 170-181.

Examples

## Not run: 
# Read tree qsm and calculate the crown diameter height ratio
qsm <- read_tree_qsm(QSM_path = "path/to/qsm.mat")
cdh_ratio <- crown_diameterheight_ratio_qsm(
  treedata = qsm$treedata,
  cylinder = qsm$cylinder
)
# with point cloud data
pc_tree <- read_tree_pc(PC_path = "path/to/point_cloud.txt")
cdh_ratio <- crown_diameterheight_ratio_qsm(
  treedata = qsm$treedata,
  cylinder = qsm$cylinder,
  pc = pc_tree
)

## End(Not run)

lmterryn/ITSMe documentation built on Feb. 4, 2025, 2:21 a.m.