An R package for computing tree crown volume, area, and morphometric indices from basic field measurements.
# remotes::install_github('sergiocostafh/crownmetrics')
install.packages("crownmetrics", repos = c('https://sergiocostafh.r-universe.dev', 'https://cloud.r-project.org'))
| Variable | Unit |
|---|---|
| Crown width / Crown length / Total height | meters |
| DBH | centimeters |
Crown volume — five geometric solid models:
crown_volume_ellipsoid(crown_width = 3.5, crown_length = 5.0)
crown_volume_cone(crown_width = 3.5, crown_length = 5.0)
crown_volume_cylinder(crown_width = 3.5, crown_length = 5.0)
crown_volume_paraboloid(crown_width = 3.5, crown_length = 5.0)
crown_volume_fan(crown_length = 5.0, dbh = 22.0)
# or via unified dispatcher
crown_volume(crown_width = 3.5, crown_length = 5.0, shape = "ellipsoid")
Crown area — profile and horizontal projection:
crown_area(crown_width = 3.5, crown_length = 5.0, shape = "ellipse")
crown_projection_area(crown_width = 3.5)
Morphometric indices:
crown_morphometrics(crown_width = 3.5, crown_length = 5.0,
total_height = 18.0, dbh = 22.0)
| Function | Index | Formula |
|---|---|---|
crown_ratio() |
CR | CL / H |
crown_form() |
CF | CW / CL |
slenderness() |
SLI | H / (DBH/100) |
salience_index() |
SAI | CW / (DBH/100) |
scope_index() |
SCI | CW / H |
vital_space_index() |
VSI | (CW / DBH_m)² |
Batch processing — all metrics for every row of a data frame:
crown_metrics(data, col_shape = "shape_code")
Shape codes: 0 = ellipsoid, 1 = cone, 2 = cylinder, 3 = paraboloid, 4 = fan.
Durlo, M. A., & Denardi, L. (1998). Morfometria de Cabralea canjerana em mata secundária nativa do Rio Grande do Sul. Ciência Florestal, 8(1), 55–66.
Zhu, Z., Kleinn, C., & Nölke, N. (2021). Assessing tree crown volume — a review. Forestry, 94(1), 18–35. https://doi.org/10.1093/forestry/cpaa037