Simulate soil organic carbon with the RothC five-pool model.

Annual RothC trajectory integrated by monthly Euler steps. Active carbon is partitioned into decomposable plant material, resistant plant material, microbial biomass and humified organic matter, plus a Falloon (1998) inert pool. Decomposed carbon is split between biomass and humus by a clay-texture function.

Usage

calculate_soc_rothc(
  initial_soc_mgc_ha,
  c_input_mgc_ha_yr,
  years,
  clay_pct = NA,
  climate_modifier = 1
)

Source

Coleman, K. & Jenkinson, D. S. (1996). doi:10.1007/978-3-642-61094-3_17 ; inert organic matter: Falloon, P. et al. (1998). doi:10.1016/S0038-0717(97)00256-3 .

Arguments

initial_soc_mgc_ha

Initial soil organic carbon stock (Mg C per ha).

c_input_mgc_ha_yr

Annual carbon input (Mg C per ha per year).

years

Number of years to simulate.

clay_pct

Soil clay content (percent).

climate_modifier

Annual climate rate modifier (dimensionless), applied to every monthly decomposition step.

Value

A tibble with one row per year: year, dpm, rpm, bio, hum, iom and soc_total.

Examples

calculate_soc_rothc(
  initial_soc_mgc_ha = 50,
  c_input_mgc_ha_yr = 2,
  years = 5,
  clay_pct = 20
)
#> # A tibble: 6 × 7
#>    year   dpm   rpm   bio   hum   iom soc_total
#>   <int> <dbl> <dbl> <dbl> <dbl> <dbl>     <dbl>
#> 1     0 0.458 0.916 2.29   42.1  4.22      50  
#> 2     1 0.174 1.40  1.46   41.7  4.22      49.0
#> 3     2 0.174 1.75  0.999  41.3  4.22      48.4
#> 4     3 0.174 2.01  0.748  40.8  4.22      48.0
#> 5     4 0.174 2.21  0.614  40.4  4.22      47.6
#> 6     5 0.174 2.35  0.543  39.9  4.22      47.2