Scheda a dose Standard - Nitrogen (DPI Emilia-Romagna 2026)

Implements the DPI 2026 simplified "Scheda a dose Standard" method for nitrogen, as coded in Fert_Office v1.26 sheet Scheda_N. Starts from a crop-specific standard base dose (from mas.table$standard_N) and applies user-selected decrement and increment factors. The final dose is then capped at MAS (maximum allowed dose) from DPI 2026 Allegato 9 / Reg. reg. 2/2024.

Usage

dose_standard_N(
  crop,
  phase = NULL,
  decrements = numeric(),
  increments = numeric(),
  mas.table = NFert::mas.table,
  apply_mas_cap = TRUE
)

scheda_N(...)

Arguments

crop: Crop name exactly as in NFert::mas.table$crop.
phase: Optional phase string (e.g. "Primaverile-estiva 100-130 gg") for crops with multiple fases. If NULL (default) and the crop has multiple rows, the first match is used and a note is emitted.
decrements: Named numeric vector (kg/ha) with one or more of: yield_low, prev_amendant, high_SOM, after_alfalfa_meadow, after_legume. Missing names default to 0. Values are treated as positive and subtracted.
increments: Named numeric vector (kg/ha) with one or more of: yield_high, low_SOM, straw_burial, rain_surplus, compacted_no_till. Missing names default to 0.
mas.table: Reference MAS lookup (default NFert::mas.table).
apply_mas_cap: Logical, default TRUE. Cap the final dose at max_N_dose = standard_N + max_increment from MAS.
...: Passed to dose_standard_N().

Value

A named list with components:

dose_base: standard dose from MAS (kg N/ha)
total_decrement, total_increment
dose_recalculated: dose after increments/decrements
max_N_dose: DPI 2026 cap
dose_final: min(dose_recalculated, max_N_dose) if apply_mas_cap = TRUE
mas_exceeded: logical

Details

The decrement/increment catalogue (with default values in kg/ha) is:

Direction	Factor	Default kg/ha
Decremento	Resa bassa (< 5 t/ha)	user-defined
Decremento	Ammendante nell'anno precedente	user-defined
Decremento	Tenore SO nel suolo elevato	user-defined
Decremento	Dopo medica o prato > 5 anni	60
Decremento	Dopo una leguminosa	30
Incremento	Resa alta (> 7 t/ha)	user-defined
Incremento	Tenore SO nel suolo basso	user-defined
Incremento	Ristoppio o interramento paglie	30
Incremento	Lisciviazione x surplus pluviometrico	user-defined
Incremento	Terreno compattato o semina su sodo	10

Examples

# Grano duro pianta intera, fase primaverile-estiva 100-130 gg
scheda_N(crop = "Grano duro (pianta intera)",
         decrements = c(after_alfalfa_meadow = 60),
         increments = c(straw_burial = 30,
                        compacted_no_till = 10))
#> Crop 'Durum wheat (whole plant)' has 2 matching rows; using the first.
#> $crop
#> [1] "Durum wheat (whole plant)"
#> 
#> $phase
#> [1] "nd"
#> 
#> $dose_base
#> [1] 160
#> 
#> $total_decrement
#> [1] 60
#> 
#> $total_increment
#> [1] 40
#> 
#> $dose_recalculated
#> [1] 140
#> 
#> $max_N_dose
#> [1] 200
#> 
#> $dose_final
#> [1] 140
#> 
#> $mas_exceeded
#> [1] FALSE
#> 
#> $units
#> [1] "kg N/ha"
#> 
#> $reference
#> [1] "DPI Emilia-Romagna 2026, Fert_Office v1.26 (Scheda_N)"
#>