C_input_cover_crops {SoilManageR} | R Documentation |
Estimate C inputs by cover crops
Description
This function estimates the Carbon (C) input into the soil system by cover crops based on the duration of the cover crop stand.
Usage
C_input_cover_crops(
abvg_biomass = NA,
days = 180,
min_C_abvg = 1253,
min_days = 180,
max_C_abvg = 1916,
max_days = 240,
Cc_biomass = 450
)
Arguments
abvg_biomass |
(optional): Dry weight of aboveground biomass of the cover crop ( |
days |
(optional): Number of days that the cover crop was established. If no value is provided, mind_days is assumed ( |
min_C_abvg |
(optional): Minimal above ground C that the cover crop produces, given it is established for the min_days number of days. Default value is 1.253 ( |
min_days |
(optional): Number of days where the interpolation of the biomass starts. The default value is 180 ( |
max_C_abvg |
(optional): Maximum biomass that the cover crop can produce. Default value is 1.916 ( |
max_days |
(optional): Number of days when the maximum biomass of the cover crop is reached. The default value is 240 ( |
Cc_biomass |
(optional): Assumed C content of the cover crop biomass. Default value is 450 ( |
Details
C_input_cover_crops()
internally calls C_input_crops()
to calculate the
different C fractions. The C in the above ground biomass (C_{Product}
)
is a function of the time a cover crop is established. A minimum and
a maximum cover crop biomass are assumed at 180 and 240 days respectively,
and linearly interpolated for the period in between.
C_{Product} = \begin{cases}
1253\ kgC/ha \ , \ duration < 180 \ days \\
1253 \ kgC/ha \ + \ (duration - 180 \ days) \ * \frac{663 \ kgC/ha}{60 \ days} \ , \ 180 \ days \leq duration \leq 240 \ days \\
1916 \ kgC/ha \ , \ duration > 240 \ days
\end{cases}
Assumptions on the C inputs at day 180 and 240 are based on values extracted from Seitz et al. (2022).
The remaining parameters to calculate the C input by cover crops are
HI = 1
, SER = 3.67
, and REF = 0.31
, all derived from Seitz et al. (2022).
Note, that with these assumptions the C input of short term cover crops (e.g. few weeks) is overestimated.
The function C_input_cover_crops()
estimates the C input by applying the
assumptions mentioned above. Alternatively, the user can
supply an above ground biomass and a CC of the biomass,
or other parameters to estimate the C input by cover crops.
Value
a tibble with the following parameters:
C_input_product: Estimated soil carbon input from product (i.e., the cover corp aboveground biomass) (
kgC/ha
),C_input_straw: Estimated soil carbon input by straw or other residues (typically 0 for cover crops) (
kgC/ha
),C_input_root: Estimated soil carbon input by roots (
kgC/ha
),C_input_exudate: Estimated soil carbon input by roots (
kgC/ha
),C_input_total: Total estimated Soil carbon input, sum of C_input_straw, C_input_root, C_input_exudate (
kgC/ha
),
References
Seitz D, Fischer LM, Dechow R, Wiesmeier M, Don A (2022). “The potential of cover crops to increase soil organic carbon storage in German croplands.” Plant and Soil, 488(1-2), 157–173. doi:10.1007/s11104-022-05438-w.
See Also
-
C_input()
to calculate C inputs for amanagement_df
-
C_input_crops()
to calculate C input for crops -
CN_input_amendments()
to calculate C (and N) inputs for organic amendments -
C_input_crops_LUT()
for the look-up-table for crop reference values
Examples
#example when only the duration is known
C_input_cover_crops(days = 205)
#example if the cover crop biomass is known
C_input_cover_crops(abvg_biomass = 2.5, Cc_biomass = 450)
#example with custom assumptions on the above ground biomass developnent over time
C_input_cover_crops(days = 60, min_C_abvg = 600 , min_days = 50, max_C_abvg = 1916, max_days = 240)