Estimate non-symbiotic biological nitrogen fixation.

Estimates free-living and associative BNF in agricultural soils from a base rate (crop-specific from bnf, or a default) scaled by environmental modifiers for nitrogen, temperature, water, soil organic matter, pH and clay. Each modifier activates only when its driver column is present.

Usage

calculate_nonsymbiotic_bnf(
  x,
  nonsymbiotic_params = list(),
  soil_params = list()
)

Arguments

x

A tibble with area_ha. Optional nonsymbiotic_base_kg_ha (or item_prod_code to join the crop-specific base rate), plus the nitrogen, temperature, water and soil (som_pct, soil_ph, clay_pct) drivers.

nonsymbiotic_params

Named list overriding nsbnf_default_kg_ha, k_n_synth, k_n_org, t_opt, t_sigma, ai_threshold.

soil_params

Named list overriding k_som, som_ref, ph_opt, ph_sigma, k_clay, clay_ref.

Value

The input tibble with nonsymbiotic_base_kg_ha, the six f_*_nonsymbiotic modifiers, f_env_nonsymbiotic and nonsymbiotic_bnf_t.

Examples

calculate_nonsymbiotic_bnf(tibble::tibble(area_ha = 40))
#> # A tibble: 1 × 18
#>   area_ha n_synth_kg_ha n_org_kg_ha temp_c pet_mm som_pct soil_ph clay_pct
#>     <dbl>         <dbl>       <dbl>  <dbl>  <dbl>   <dbl>   <dbl>    <dbl>
#> 1      40             0           0     NA     NA      NA      NA       NA
#> # ℹ 10 more variables: water_input_mm <dbl>, nonsymbiotic_base_kg_ha <dbl>,
#> #   f_nitrogen_nonsymbiotic <dbl>, f_temperature_nonsymbiotic <dbl>,
#> #   f_water_nonsymbiotic <dbl>, f_som_nonsymbiotic <dbl>,
#> #   f_ph_nonsymbiotic <dbl>, f_clay_nonsymbiotic <dbl>,
#> #   f_env_nonsymbiotic <dbl>, nonsymbiotic_bnf_t <dbl>