Classify exchangeable potassium availability

Classifies K (or K2O) availability by soil texture grouping, following DPI Emilia-Romagna 2026 (Fert_Office v1.26 foglio Gri_K). The threshold ranges depend on the DPI texture group (Sabbiosi, Medio impasto, Argillosi e limosi).

Usage

classify_K(
  value,
  unit = c("K", "K2O"),
  soil_group,
  k_availability.table = NFert::k_availability.table
)

Arguments

value: Numeric K or K2O value in ppm.
unit: "K" (default) or "K2O". Conversion K2O = K / 0.83333.
soil_group: Texture grouping (must match k_availability.table$group).
k_availability.table: Lookup table, default NFert::k_availability.table.

Value

A list with value_ppm_K, value_ppm_K2O, ID_Gri_K, rating, strategy (Arricchimento / Mantenimento / Riduzione).

Examples

classify_K(value = 150, unit = "K2O", soil_group = "Medio impasto")
#> $value_ppm_K
#> [1] 124.9995
#> 
#> $value_ppm_K2O
#> [1] 150
#> 
#> $ID_Gri_K
#> [1] 3
#> 
#> $rating
#> [1] "medium"
#> 
#> $strategy
#> [1] "Mantenimento"
#>