C_input_crops {SoilManageR}R Documentation

Estimate C inputs by crops

Description

Calculates the estimated carbon (C) input into the soil system by harvested main crops.

Usage

C_input_crops(
  crop,
  crop_product = NA,
  crop_residue = NA,
  harvest_index = NA,
  variable_harvest_index = NA,
  HI_intercept = NA,
  HI_slope = NA,
  shoot_root_ratio = NA,
  root_exudation_factor = NA,
  Cc_product = 450,
  Cc_residue = 450,
  Cc_root = 450,
  straw.removal = NA,
  fixed_belowground_input = NA,
  fixed_C_input_root = NA,
  return.comment = FALSE
)

Arguments

crop

Crop type. Must match predefined list (see C_input_crops_LUT)

crop_product

(optional) Dry weight of the exported product, i.e. yield. Default value is taken from table (tDM/ha)

crop_residue

(optional) Dry weight of the residues of the main crop (e.g., straw, sugar beet leaves) (tDM/ha)

harvest_index

(optional) Ratio of the product to the total above ground biomass

variable_harvest_index

(optional) Logical value that is TRUE if the variable harvest index assumptions of Fan et al. (2017) are to be applied (TRUE / FALSE)

HI_intercept

(optional) Intercept of the variable harvest index. Values provided by Fan et al. (2017)

HI_slope

(optional) Slope of the variable harvest index. Values provided by Fan et al. (2017) (ha/tDM)

shoot_root_ratio

(optional) Ratio of the total above ground biomass to the root biomass

root_exudation_factor

(optional) Ratio of the root exudated C to the C in the root biomass

Cc_product

(optional) C concentration in the exported product. Default value is 450 (gC/kgDM)

Cc_residue

(optional) C concentration in the residues of the main crop. Default value is 450 (gC/kgDM)

Cc_root

(optional) C concentration in the roots. Default value is 450 (gC/kgDM)

straw.removal

(optional) Logical value that is TRUE if straw is removed at harvest.

  • When NA then SR value from table is take

  • When TRUE SS is 1

  • When FALSE SS is 0.

  • Default value is NA

fixed_belowground_input

(optional) Logical value that is TRUE if fixed below ground Carbon inputs are to be assumed (e.g. for temporary leys) (TRUE / FALSE)

fixed_C_input_root

(optional) amount of root C that is assumed if fixed_belowground_input is TRUE (kgC/ha)

return.comment

(optional) logical value if comment are returned or not. Default = FALSE (TRUE/FALSE)

Details

The annual C input by crops were estimated based on crop type and crop yield with the allometric functions of Bolinder et al. (2007):

C_{Product} = Product * CC_{Product}

C_{Straw} = {Product}* \frac{1 - HI}{HI} * CC_{Straw}

C_{Root} = \frac{Product}{SRR*HI} * CC_{Root}

C_{Exudates} = C_{Root} * REF

Where C is the C per fraction (in kgC/ha) and CC is the C content of given fraction (kgC/tDM). Prodcuct is the dry matter yield of a crop in tDM/ha, HI is the harvest index (ratio of product total of product and straw), SRR is the ratio of the shoot biomass (product and straw) to the root biomass, and REF is the root exudation factor (i.e., the ratio of the C exudated by the roots to the C in the root biomass). All fractions are multiplied with a crop and fraction specific S-factor that determines the share of the fraction that is returned to the soil.

If not mentioned otherwise parameters were taken from the publications of Bolinder et al. (2007), Keel et al. (2017) or Wüst-Galley et al. (2020). Parameters for potatoes and sugar beets were derived from Bolinder et al. (2015) For temporary leys we assumed yield-independent annual C_{Root} of 1.5 MgC/ha and a REF of 0.5 (Taghizadeh-Toosi et al. 2020). Furthermore, like Wüst-Galley et al. (2020), the belowground C input (C_{Root} + C_{Exudates}) of corn maize, silage maize and cereals were fixed to 0.46 MgC/ha, 1.1 MgC/ha and 0.6 MgC/ha respectively, based on the values from Hirte et al. (2018). Additionally, we applied the yield dependent harvest index (HI = Intercept + Product * Slope) proposed by Fan et al. (2017) for cereals, faba beans, peas, corn, rapeseed, and soybeans.

Reference yields were derived from the Swiss fertilizer recommendations Sinaj et al. (2017).

All default values can be found in the look-up-table C_input_crops_LUT.

Value

a tibble with the following parameters:

References

Bolinder MA, Janzen HH, Gregorich EG, Angers DA, VandenBygaart AJ (2007). “An approach for estimating net primary productivity and annual carbon inputs to soil for common agricultural crops in Canada.” Agriculture, Ecosystems & Environment, 118(1-4), 29–42. doi:10.1016/j.agee.2006.05.013.

Bolinder MA, Kätterer T, Poeplau C, Börjesson G, Parent LE (2015). “Net primary productivity and below-ground crop residue inputs for root crops: Potato (Solanum tuberosum L.) and sugar beet (Beta vulgaris L.).” Canadian Journal of Soil Science, 95(2), 87–93. doi:10.4141/cjss-2014-091.

Fan J, McConkey B, Janzen H, Townley-Smith L, Wang H (2017). “Harvest index - yield relationship for estimating crop residue in cold continental climates.” Field Crops Research, 204, 153–157. doi:10.1016/j.fcr.2017.01.014.

Hirte J, Leifeld J, Abiven S, Oberholzer H, Mayer J (2018). “Below ground carbon inputs to soil via root biomass and rhizodeposition of field-grown maize and wheat at harvest are independent of net primary productivity.” Agriculture, Ecosystems & Environment, 265, 556–566. doi:10.1016/j.agee.2018.07.010.

Keel SG, Leifeld J, Mayer J, Taghizadeh-Toosi A, Olesen JE (2017). “Large uncertainty in soil carbon modelling related to method of calculation of plant carbon input in agricultural systems.” European Journal of Soil Science, 68(6), 953–963. doi:10.1111/ejss.12454.

Sinaj S, Charles R, Baux A, Dupuis B, Hiltbrunner J, Levy Häner L, Pellet D, Blanchet G, Jeangros B (2017). “Grundlagen für die Düngung landwirtschaftlicher Kulturen in der Schweiz (GRUD): Düngung von Ackerkulturen.” Agrarforschung Schweiz, Spezialpublikation, Chapter 8(6), 1–46. https://ira.agroscope.ch/en-US/Page/Publikation/Index/36799.

Taghizadeh-Toosi A, Cong W, Eriksen J, Mayer J, Olesen J, Keel SG, Glendining M, Kätterer T, Christensen BT (2020). “Visiting dark sides of model simulation of carbon stocks in European temperate agricultural soils: allometric function and model initialization.” Plant and Soil, 450(1-2), 255–272. doi:10.1007/s11104-020-04500-9.

Wüst-Galley C, Keel SG, Leifeld J (2020). “A model-based carbon inventory for Switzerland’s mineral agricultural soils using RothC.” Agroscope Science, 1–110. doi:10.34776/as105e.

See Also

Examples

#example without yield information, default yield is assumed
C_input_crops("wheat, winter")

#example with yield information and straw retention
C_input_crops("barley, spring", crop_product = 4.5, straw.removal = FALSE)

#example with more information
C_input_crops("barley, spring", crop_product = 4.5, harvest_index = 0.4,
              shoot_root_ratio = 2.4, root_exudation_factor = 0.5)

#example with variable harvest index
C_input_crops("barley, spring", crop_product = 4.5, variable_harvest_index = TRUE,
              HI_intercept = 0.35, HI_slope = 0.015, shoot_root_ratio = 2.4,
              root_exudation_factor = 0.5)

#example with fixed below ground input
C_input_crops("maize, silage", crop_product = 18.5, 
              fixed_belowground_input = TRUE, fixed_C_input_root = 1500,
              root_exudation_factor = 0.3) 

[Package SoilManageR version 1.1.0 Index]