Fill missing horizon attributes from a SoilGrids depth prior — apply_soilgrids_depth

For each horizon and each requested attribute, interpolates the value at the horizon's mid-depth from the six standard SoilGrids 2.0 depth slices (0-5, 5-15, 15-30, 30-60, 60-100, 100-200 cm) and writes it into the pedon with source = "inferred_prior". Existing values are preserved unless overwrite = TRUE; the PedonRecord authority order means a SoilGrids prior can never silently displace a measured, spectra-predicted or VLM-extracted value.

Usage

apply_soilgrids_depth_prior(
  pedon,
  attrs = NULL,
  depth_profiles = NULL,
  overwrite = FALSE
)

Arguments

pedon: A PedonRecord with at least one horizon. For the live fetch it must also carry site$lat and site$lon.
attrs: Character vector of horizon columns to fill. Defaults to all SoilGrids-backed attributes: clay_pct, sand_pct, silt_pct, ph_h2o, oc_pct, cec_cmol.
depth_profiles: Optional named list mapping an attribute to a numeric vector of six slice values (0-5 ... 100-200 cm). When supplied the SoilGrids network call is skipped entirely – this is the path the test suite and offline users take.
overwrite: If FALSE (default) only NA cells are filled. If TRUE, every requested cell is overwritten (subject to the provenance authority order).

Value

Invisibly, the mutated pedon. An attribute "soilgrids_depth_fill" on the return value records how many cells were filled.

Details

This is the depth-resolved companion to spatial_prior_soilgrids (which returns a site-level RSG probability vector, not horizon attributes), and the attribute-fill stage of classify_from_photos.

Examples

if (FALSE) { # \dontrun{
p <- make_cambisol_canonical()
p$horizons$clay_pct <- NA_real_
# Offline: supply the six-slice profiles directly.
apply_soilgrids_depth_prior(
  p, attrs = "clay_pct",
  depth_profiles = list(clay_pct = c(18, 20, 24, 28, 30, 30)))
} # }