Simulate soil organic carbon with the HSOC two-pool model.

Annual HSOC trajectory (Spain historical pipeline): a fresh and a humus decomposing pool plus an inert organic matter pool. The inert pool is the Falloon (1998) function of initial carbon. Each year a pool stock loses first-order decomposition and gains its carbon input. Land-use-change carbon transfer is deferred to a later phase (single land use here).

Usage

calculate_soc_hsoc(
  initial_soc_mgc_ha,
  c_input_mgc_ha_yr,
  years,
  clay_pct = NA,
  climate_modifier = 1,
  humification_fraction = 0.3
)

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); unused, kept for contract.
climate_modifier: Annual climate rate modifier (dimensionless).
humification_fraction: Fraction of carbon input humified into the humus pool (the remainder feeds the fresh pool).

Value

A tibble with one row per year: year, fresh, humus, iom and soc_total.

Examples

calculate_soc_hsoc(
  initial_soc_mgc_ha = 50,
  c_input_mgc_ha_yr = 2,
  years = 5
)
#> # A tibble: 6 × 5
#>    year fresh humus   iom soc_total
#>   <int> <dbl> <dbl> <dbl>     <dbl>
#> 1     0  2.92    30  4.22      37.1
#> 2     1  2.92    30  4.22      37.1
#> 3     2  2.92    30  4.22      37.1
#> 4     3  2.92    30  4.22      37.1
#> 5     4  2.92    30  4.22      37.1
#> 6     5  2.92    30  4.22      37.1