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re-writes leafR steps to allow for treeID as input for ladderfuelsR or ladderfuelsr_cbh()

Source: R/leafr_for_ladderfuelsr.R
leafr_for_ladderfuelsr.Rd

leafr_for_ladderfuelsr() is a re-write of leafR::lad.voxels() and leafR::lad.profile() to:

  • removes the requirement to use a file written to disk

  • allows for the calculation of LAD by the treeID attribute so that don't have to pass individual tree point clouds

  • updates to the use of the latest lidR functionality and removes the use of sp and raster functions

  • updates the function to tidy data manipulation

Usage

leafr_for_ladderfuelsr(
  las,
  voxel_grain_size_m = 1,
  k = 1,
  attribute = "treeID",
  min_pulses = 0,
  relative = FALSE
)

Arguments

las

an object of class LAS that has been height normalized.

voxel_grain_size_m

numeric. horizontal resolution (suggested 1 meter for lad profiles and 10 meters for LAI maps). See grain.size in leafR::lad.voxels()

k

numeric. coefficient to transform effective LAI to real LAI (k = 1; for effective LAI)

attribute

character. The column name of the attribute to group the return LAD profile by. Default is "treeID". The attribute (whatever it is defined as) must exist in the las data

min_pulses

numeric. minimum number of pulses required to return a record by attribute. set to zero (default) to leave data unfiltered.

relative

logical. produce lad profile by relative total LAI values. Indicate when using effective LAI value. if set to TRUE, lad value will be relative_lad; otherwise, lad value will be mean_lad

Value

Returns an data.frame which can have multiple treeIDs to use as input for ladderfuelsr_cbh()

References

  • https://doi.org/10.3390/rs11010092 Almeida, D. R. A. D., Stark, S. C., Shao, G., Schietti, J., Nelson, B. W., Silva, C. A., ... & Brancalion, P. H. S. (2019). Optimizing the remote detection of tropical rainforest structure with airborne lidar: Leaf area profile sensitivity to pulse density and spatial sampling. Remote Sensing, 11(1), 92. https://github.com/DRAAlmeida/leafR

Examples

 if (FALSE) { # \dontrun{
 # polygon data
 f <- system.file(package = "cloud2trees","extdata","crowns_poly.gpkg")
 trees_poly <- sf::st_read(f)
 # simplify polygons
 trees_poly <- simplify_multipolygon_crowns(trees_poly)
 # point cloud data
 lf <- system.file(package = "cloud2trees","extdata","norm_las","RMNP_017_2018_normalize.las")
 las <- lidR::readLAS(lf)
 las@data %>% dplyr::glimpse()
 # polygon_attribute_to_las to attach treeID to las
 las <- polygon_attribute_to_las(las, trees_poly, force_crs = T, attribute = "treeID")
 las@data %>% dplyr::glimpse()
 # get the lad profile for each treeID
 lad_profile <- leafr_for_ladderfuelsr(
     las
     , voxel_grain_size_m = 1
     , k = 1
     , group_treeID = T
     , relative = F
   )
 dplyr::glimpse(lad_profile)
 } # }