P2: Site Productivity Index Indicator — indicator_productive

Calculates a site productivity index combining soil fertility, climate suitability, and species-specific growth potential using reference productivity tables.

Usage

indicator_productive_station(
  units,
  species_field = "species",
  fertility_field = "fertility",
  climate_field = "climate",
  productivity_table = NULL,
  column_name = "P2",
  lang = "en"
)

Arguments

units: sf object (POLYGON) of spatial units to assess
species_field: Character. Column name containing species codes. Default "species".
fertility_field: Character. Column name containing fertility class (1=high, 2=medium, 3=low). Default "fertility".
climate_field: Character. Column name containing climate zone. Default "climate".
productivity_table: Data.frame. Custom productivity reference table. If NULL, uses bundled ONF/IFN tables.
column_name: Character. Name for output column. Default "P2".
lang: Character. Message language. Default "en".

Value

sf object with added column: P2 (annual increment in m3/ha/yr)

Details

**Calculation**:

Lookup reference productivity from ONF/IFN tables
Match by species x fertility class x climate zone
P2 = annual increment (m3/ha/year) for the site

**Fertility Classes**:

1: High fertility (rich soils, optimal drainage)
2: Medium fertility (average conditions)
3: Low fertility (poor soils, constraints)

**Climate Zones**:

temperate_oceanic: Atlantic climate (Brittany, Normandy)
temperate_continental: Continental (Lorraine, Burgundy)
mountainous: Mountain zones (Alps, Pyrenees, Massif Central)
atlantic: Southwest Atlantic (Landes, Gironde)
mediterranean: Mediterranean (Provence, Languedoc)

Examples

if (FALSE) { # \dontrun{
units$species <- c("FASY", "PIAB", "QUPE")
units$fertility <- c(1, 2, 2)
units$climate <- c("temperate_oceanic", "mountainous", "temperate_oceanic")

result <- indicator_productive_station(
  units = units,
  species_field = "species",
  fertility_field = "fertility",
  climate_field = "climate"
)
} # }