Animal waste management systems (55_awms)

Current contract

This module calculates nutrient (NPK) dynamics in the animal waste management systems and their N2O emissions.



Name Description Unit A B
$vm\_prod\_reg(i,k)$ regional aggregated production Mt DM x
$fm\_prod\_kli\_1995(i,kli)$ attributes of harvested organs Mt DM x
$fm\_ipcc\_ef(ipcc_ef,emis_uncertainty)$ emission factors 1 x
$vm\_res\_use\_feed(i,kli,npk)$ residues used for feed distinguished by kli Mt nutrients x
$vm\_convby\_feed(i,kli,npk)$ nutrients in conversion byproducts fed to livestock by kli Mt nutrients x
$vm\_dem\_feed(i,kli,kbio)$ feed demand including byproducts Mt DM x
$fm\_feeding\_convergence(t)$ merging of input data scenarios: merging rates over time 1 x

The last columns of the table indicate the usage in the different realizations (numbered with capital letters)


Name Description Unit
$vm\_btm\_reg(i,emis_reg)$ emissions before technical mitigation Mt N2O-N CH4 C x x
$vm\_manure\_cropland(i,npk)$ Manure being recycled to croplands Mt nutrients x x

Interface plot

Interfaces AWMS module

Figure 0: Information exchange among modules


(A) ipcc_2006 (default)

Calculates nutrient dynamics and N2O emissions in the animal waste management sector.

A detailed description of this module and of underlying data sources can be found in Bodirsky et al (2012) "N2O emission from the global agricultural nitrogen cycle: Current state and future scenarios").

Nutrients in excreted manure is calculated as the nutrients in feed minus the nutrients in slaughtered animals. Nutrients in grazed biomass from pasture and scavenging is assumed to be returned to pastures (grazing_pasture, equation 1) or collected as fuel (fuel, equation 2). Nutrients in stubble grazing on croplands is assumed to be returned directly to croplands (grazing_cropland, equation 3). Nutrients in concentrate feed, conversion byproducts, harvested crop residues, and animal feed is assumed to be fed to animals living in stables(confinement, equation 4), which is later-on partly recycled to croplands (equation 5). To distribute the nutrient withdrawals from slaughtered animals between these categories, we used shares of animal waste management systems from the IPCC Guidelines for National Greenhouse Gas Inventories (IPCC 2006)[2]. As stubble grazing is not represented in these guidelines, and as stubble grazing is only a minor category, we allocated the withdrawals from the respective slaughtered animals to "confinement" to avoid cases with negative numbers.

Equation 1:
& v55\_manure(i, kli, \text{"$grazing\_pasture$"},npk)\\
& = \\
& (vm\_dem\_feed(i,kli,\text{"$pasture$"})\\
& +vm\_dem\_feed(i,kli,\text{"$scavenging$"})) * im\_attributes\_harvest(npk,\text{"$pasture$"})\\
& *(1-ic55\_manure\_fuel\_shr(i,kli))\\
& - vm\_prod\_reg(i,kli) * ic55\_animal\_shr\_awms(i,kli,\text{"$grazing\_pasture$"})\\
& *f55\_slaughter\_factor(kli)*f55\_attributes\_living\_animals(npk,kli)\\

Equation 2:
& v55\_manure(i, kli, \text{"$fuel$"},npk)\\
& = \\
& (vm\_dem\_feed(i,kli,\text{"$pasture$"})\\
& +vm\_dem\_feed(i,kli,\text{"$scavenging$"})) * im\_attributes\_harvest(npk,\text{"$pasture$"})*ic55\_manure\_fuel\_shr(i,kli)\\
& - vm\_prod\_reg(i,kli) * ic55\_animal\_shr\_awms(i,kli,\text{"$fuel$"})\\
& *f55\_slaughter\_factor(kli)*f55\_attributes\_living\_animals(npk,kli)\\

Equation 3:
& v55\_manure(i, kli, \text{"$grazing\_cropland$"},npk)\\
& = \\
& vm\_res\_use\_feed(i,kli,npk) * ic55\_feedres\_to\_cropl\_shr(i)\\

Equation 4:
& v55\_manure(i, kli, \text{"$confinement$"},npk)\\
& = \\
& \sum_{kcr}(vm\_dem\_feed(i,kli,kcr) * im\_attributes\_harvest(npk,kcr))\\
& + \sum_{kli2}(vm\_dem\_feed(i,kli,kli2) * f55\_attributes\_livstproducts(npk,kli2))\\
& + vm\_convby\_feed(i, kli, npk)\\
& + vm\_res\_use\_feed(i,kli, npk) * (1-ic55\_feedres\_to\_cropl\_shr(i))\\
& - vm\_prod\_reg(i,kli) * (ic55\_animal\_shr\_awms(i,kli,\text{"$confinement$"})\\
& +ic55\_animal\_shr\_awms(i,kli,\text{"$grazing\_cropland$"})) * f55\_slaughter\_factor(kli) * f55\_attributes\_living\_animals(npk,kli)\\

Some manure is recycled and returned to croplands (see 51_nitrogen and 54_phosphorus.

Equation 5:

& vm\_manure\_cropland(i,npk) \\
& =\\
& \sum_{kli}( v55\_manure(i, kli, \text{"$grazing\_cropland$"},npk))\\
& + \sum_{kli}( v55\_manure(i, kli, \text{"$confinement$"},npk)*ic55\_recycl\_conf(i,kli,npk)*ic55\_conf\_to\_cropl\_shr(i))\\

N2O emissions are estimated based on the IPCC Guidelines for National Greenhouse Gas Inventories (IPCC 2006)[1].
They include emissions from manure applied to croplands (equation 6), manure excreted to pastures (equation 7), and animal waste management (equation 8).
All emissions are estimated without application of mitigation technologies. These technologies are applied in the 57_maccs module.

Equation 6:

& vm\_btm\_reg(i,\text{"$man\_crop\_n2o$"}) \\
& = \\
& \sum_{kli}( v55\_manure(i, kli, \text{"$confinement$"}, \text{"$nr$"})*ic55\_recycl\_conf(i,kli, \text{"$nr$"})) \\
& * ( fm\_ipcc\_ef(\text{"$ef\_1$"},\text{"$best$"}) \\
& + fm\_ipcc\_ef(\text{"$frac\_gasm$"},\text{"$best$"}) * fm\_ipcc\_ef(\text{"$ef\_4$"},\text{"$best$"}) \\
& + fm\_ipcc\_ef(\text{"$frac\_leach\_h$"},\text{"$best$"}) * fm\_ipcc\_ef(\text{"$ef\_5$"},\text{"$best$"}) \\
& )

Equation 7:

& vm\_btm\_reg(i,\text{"$man\_past\_n2o$"}) \\
& = \\
& \sum_{awms\_prp,kli}( v55\_manure(i, kli, awms\_prp, \text{"$nr$"})* \\
& ( ic55\_n2o\_ipcc\_ef3\_prp(i,kli) \\
& + fm\_ipcc\_ef(\text{"$frac\_gasm$"},\text{"$best$"}) * fm\_ipcc\_ef(\text{"$ef\_4$"},\text{"$best$"}) \\
& + fm\_ipcc\_ef(\text{"$frac\_leach\_h$"},\text{"$best$"}) * fm\_ipcc\_ef(\text{"$ef\_5$"},\text{"$best$"})) \\
& )

Equation 8:

& vm\_btm\_reg(i,\text{"$awms\_n2o$"}) \\
& = \\
& \sum_{kli}( v55\_manure(i, kli, \text{"$confinement$"}, \text{"$nr$"}) \\
& * ( ic55\_n2o\_conf\_direct\_emis(i,kli) \\
& + ic55\_NHxNOy\_conf\_loss\_gas(i,kli) * fm\_ipcc\_ef(\text{"$ef\_4$"},\text{"$best$"})) \\
& )

(B) off

animal waste management switched off. vm_manure_cropland fixed to 0.


Name Description Unit
v55_nr_manure(i, kli, awms) Nr in manure t Nr
ic55_recycl_conf(i,kli) Recycling rates of Nr excreted in confinements Share
ic55_conf_to_cropl_shr(i) Share of recycled manure applied to croplands Share
ic55_manure_fuel_shr(i,kli) Manure excreted on pastures collected as fuel Share
ic55_animal_shr_awms(i,kli,awms) Share of animals within animal waste management systems Share
f55_slaughter_factor(kli) Slaughter factor to derive liveweight from slaughterweight Ratio
f55_attributes_living_animals(dm_nr_ge,kli) Nutrient content of living animals Share
ic55_feedres_to_cropl_shr(i) Share of crop residues being directly excreted on croplands Share
i55_n_content_kli(kli) Nitrogen content of livestock products t Nr per t DM
vm_btm_reg(i,emis) Emissions before technical mitigation Tg N2O-N
fm_ipcc_ef(ipcc_ef,emis_uncertainty) Emission factors Share
ic55_conf_loss_gas(i,kli) IPCC Emission factors: volatilized losses in confinements Share
ic55_conf_direct_emis(i,kli) IPCC Emission factors: direct N2O emissions in confinements Share
ic55_ipcc_ef3_prp(i,kli) IPCC Emission factors Share
Set Elements Description
ghg n2o_n, ch4, co2_c Greenhouse gases
npk nr,p,k Plant nutrients Nitrogen, Phosphorus and Potash
fixation i_fix_production, i_fix_area N fixation by area or production
emis_way direct,leach,volat direct or indirect emission pathways
emis_uncertainty best,low, high different estimates for emission parameters
ipcc_ef frac_gasf,frac_gasm,frac_leach,frac_leach_h,ef_1,ef_1fr,ef_2,ef_4,ef_5 emission factors


Benjamin Bodirsky

See Also

[[mo:Coding Etiquette]] 51_nitrogen 54_phosphorus 57_maccs

See also


1 IPCC: 2006 Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programme, Institute for Global Environmental Strategies, Kanagawa, Japan, 2006.