The nitrogen module calculates nitrogeneous emissions before technical mitigation, including N2O, NOx, NH3, NO3- and N2. Sources of these emissions include manure, inorganic fertilizers, crop residues, soil organic matter, and indirect emissions.
| Description | Unit | A | B | |
|---|---|---|---|---|
| im_maccs_mitigation (t, i, emis_source, pollutants) |
Technical mitigation of GHG emissions | \(percent\) | x | |
| vm_emissions_reg (i, emis_source, pollutants) |
Regional emissions by source and gas after technical mitigation N CH4 C | \(Tg/yr\) | x | x |
| vm_manure (i, kli, awms, npk) |
Calculation of manure excreted in confinements | \(10^6 t X\) | x | |
| vm_manure_confinement (i, kli, awms_conf, npk) |
Manure excreted in confinements managed in different awms | \(10^6 t X\) | x | |
| vm_manure_recycling (i, npk) |
Manure being recycled to croplands | \(10^6 t X\) | x | |
| vm_nr_eff (i) |
Cropland nutrient uptake efficiency | \(Tg N/yr\) | x | |
| vm_nr_eff_pasture (i) |
Pasture nutrient uptake efficiency | \(Tg N/yr\) | x | |
| vm_nr_inorg_fert_reg (i, land_ag) |
Inorganic fertilizer application | \(Tg N/yr\) | x | |
| vm_nr_som (j) |
Release of soil organic matter | \(Mt N/yr\) | x | |
| vm_res_ag_burn (i, kcr, attributes) |
Residues burned on fields in respective attribute units DM GJ Nr P K WM C | \(10^6 tX\) | x | |
| vm_res_recycling (i, npk) |
Residues recycled to croplands in respective nutrients Nr P K units | \(10^6 tX\) | x |
Emissions are set to zero.
Limitations There are no known limitations.
The nitrogen module calculates nitrogeneous emissions before technical mitigation, including N2O, NOx, NH3, NO3- and N2. The model receives information on nitrogen flows from 50_nr_soil_budget, 55_awms, 18_residues, 59_som, and it provides the emissions to the module 56_ghg_policy. Emissions factors estimates are largely based on the IPCC 2006 Guidelines for National Greenhouse Gas Inventories (IPCC (2006).), as described in (Bodirsky et al. (2012).).
Nitrogeneous emissions stem from manure applied to croplands, inorganic fertilizers, crop residues decaying on fields, the burning of agricultural residues, soil organic matter loss, animal waste management, and manure excreted on pasture land. Additionally, part of the NH3 and NOx emissions as well as leached NO3 later result in indirect emissions of N2O when they are redeposited, nitrified and dinitrified.
Emissions are rescaled using the nitrogen uptake efficiency. This is done to keep consistency of emissions with nitrogen surplus and take account for improved emission factors when NUE increases. The marginal abatement cost curves (MACCs) are already applied at the estimation of the NUE in module 50_nr_soil_budget.
Manure applied to croplands:
\[\begin{multline*} vm\_emissions\_reg(i2,"man\_crop",n\_pollutants\_direct) = \frac{ vm\_manure\_recycling(i2,"nr") }{ \left(1-s51\_snupe\_base\right) } \cdot \left(1-vm\_nr\_eff(i2)\right) \cdot \sum_{ct} i51\_ef\_n\_soil(ct,i2,n\_pollutants\_direct,"man\_crop") \end{multline*}\]
inorganic fertilizers:
\[\begin{multline*} vm\_emissions\_reg(i2,"inorg\_fert",n\_pollutants\_direct) = \frac{ vm\_nr\_inorg\_fert\_reg(i2,"crop") }{ \left(1-s51\_snupe\_base\right) } \cdot \left(1-vm\_nr\_eff(i2)\right) \cdot \sum_{ct} i51\_ef\_n\_soil(ct,i2,n\_pollutants\_direct,"inorg\_fert") +\frac{ vm\_nr\_inorg\_fert\_reg(i2,"past") }{ \left(1-s51\_nue\_pasture\_base\right) } \cdot \left(1-vm\_nr\_eff\_pasture(i2)\right) \cdot \sum_{ct} i51\_ef\_n\_soil(ct,i2,n\_pollutants\_direct,"inorg\_fert") \end{multline*}\]
crop residues decaying on fields:
\[\begin{multline*} vm\_emissions\_reg(i2,"resid",n\_pollutants\_direct) = vm\_res\_recycling(i2,"nr") \cdot \frac{ \sum_{ct} i51\_ef\_n\_soil(ct,i2,n\_pollutants\_direct,"resid") }{ \left(1-s51\_snupe\_base\right) } \cdot \left(1-vm\_nr\_eff(i2)\right) \end{multline*}\]
emissions from burning crop residues, N2O and NOx
\[\begin{multline*} vm\_emissions\_reg(i2,"resid\_burn",n\_pollutants\_direct) = \sum_{kcr} vm\_res\_ag\_burn(i2,kcr,"dm") \cdot f51\_ef\_resid\_burn(n\_pollutants\_direct) \end{multline*}\]
soil organic matter loss:
\[\begin{multline*} vm\_emissions\_reg(i2,"som",n\_pollutants\_direct) = \sum_{cell(i2,j2)}vm\_nr\_som(j2) \cdot \frac{ \sum_{ct} i51\_ef\_n\_soil(ct,i2,n\_pollutants\_direct,"som") }{ \left(1-s51\_snupe\_base\right) } \cdot \left(1-vm\_nr\_eff(i2)\right) \end{multline*}\]
animal waste management Here we apply the marginal abatement cost curves to the emissions of all N pollutants. The measures (e.g. decreased storage time, coverage) are not specific to N2O and assumed to apply also to NH3 and other losses.
\[\begin{multline*} vm\_emissions\_reg(i2,"awms",n\_pollutants\_direct) = \sum_{kli,awms\_conf}\left( vm\_manure\_confinement(i2,kli,awms\_conf,"nr") \cdot f51\_ef3\_confinement(i2,kli,awms\_conf,n\_pollutants\_direct)\right) \cdot \left(1-\sum_{ct} im\_maccs\_mitigation(ct,i2,"awms","n2o\_n\_direct")\right) \end{multline*}\]
and manure excreted on pasture land:
\[\begin{multline*} vm\_emissions\_reg(i2,"man\_past",n\_pollutants\_direct) = \frac{ \sum_{awms\_prp,kli}\left( vm\_manure\left(i2, kli, awms\_prp, "nr"\right) \cdot f51\_ef3\_prp(i2,n\_pollutants\_direct,kli)\right) }{ \left(1-s51\_nue\_pasture\_base\right) } \cdot \left(1-vm\_nr\_eff\_pasture(i2)\right) \end{multline*}\]
Indirect emissions from NH3, NOx and NO3:
\[\begin{multline*} vm\_emissions\_reg(i2,emis\_source\_n51,"n2o\_n\_indirect") = \sum_{pollutant\_nh3no2\_51}vm\_emissions\_reg(i2,emis\_source\_n51,pollutant\_nh3no2\_51) \cdot f51\_ipcc\_ef("ef\_4","best") + vm\_emissions\_reg(i2,emis\_source\_n51,"no3\_n") \cdot f51\_ipcc\_ef("ef\_5","best") \end{multline*}\]
Limitations There are no known limitations.
| Description | Unit | A | B | |
|---|---|---|---|---|
| f51_ef_n_soil (t_all, i, n_pollutants_direct, emis_source_n_cropsoils51) |
ipcc emission factors for various emission types X | \(tX-N/tN\) | x | |
| f51_ef_resid_burn (n_pollutants_direct) |
emission factor for residual burning | \(tX-N/t DM\) | x | |
| f51_ef3_confinement (i, kli, awms_conf, n_pollutants_direct) |
emissions from manure managed in confinement for various emission types X | \(tX-N/tN\) | x | |
| f51_ef3_prp (i, n_pollutants_direct, kli) |
emissions from manure on pasture range and paddocks for various emission types X | \(tX-N/tN\) | x | |
| f51_ipcc_ef (ipcc_ef51, emis_uncertainty51) |
ipcc emission factors for various emission types X | \(tX-N/tN\) | x | |
| i51_ef_n_soil (t, i, n_pollutants_direct, emis_source_n_cropsoils51) |
emission factors for nitrogen emissions from cropland soils | \(tX-N/tN\) | x | |
| q51_emissionbal_awms (i, n_pollutants_direct) |
estimates various emission types X from animal waste management systems before technical mitigation | \(Mt X-N\) | x | |
| q51_emissionbal_man_past (i, n_pollutants_direct) |
estimates various emission types X from manure on pasture land before technical mitigation | \(Mt X-N\) | x | |
| q51_emissions_indirect_n2o (i, emis_source_n51) |
estimates various emission types X from volatilisation and leaching | \(Mt X-N\) | x | |
| q51_emissions_inorg_fert (i, n_pollutants_direct) |
estimates various emission types X from inorganic fertilizer before technical mitigation | \(Mt X-N\) | x | |
| q51_emissions_man_crop (i, n_pollutants_direct) |
estimates various emission types X from manure on cropland before technical mitigation | \(Mt X-N\) | x | |
| q51_emissions_resid (i, n_pollutants_direct) |
estimates various emission types X from residues before technical mitigation | \(Mt X-N\) | x | |
| q51_emissions_resid_burn (i, n_pollutants_direct) |
estimates various emission types X from residues burning | \(Mt X-N\) | x | |
| q51_emissions_som (i, n_pollutants_direct) |
estimates various emission types X from soil organic matter loss before technical mitigation | \(Mt X-N\) | x | |
| s51_nue_pasture_base | assumption on implicit SNuPE in ipcc guidelines | \(1\) | x | |
| s51_snupe_base | assumption on implicit SNuPE in ipcc guidelines | \(1\) | x |
| description | |
|---|---|
| attributes | Product attributes characterizing a product (such as weight or energy content) |
| awms | animal waste management systems |
| awms_conf | animal waste management systems in confinements |
| awms_prp(awms) | animal waste management systems pasture range and paddock |
| cell(i, j) | number of LPJ cells per region i |
| ct(t) | Current time period |
| emis_source | Emission sources |
| emis_source_n_cropsoils51(emis_source) | activities that lead to emissions |
| emis_source_n51(emis_source) | Emission sources from agriculture |
| emis_uncertainty51 | Different estimates for emission parameters |
| i | all economic regions |
| i2(i) | World regions (dynamic set) |
| ipcc_ef51 | ipcc Emission factors |
| j | number of LPJ cells |
| j2(j) | Spatial Clusters (dynamic set) |
| kcr(kve) | Cropping activities |
| kli(kap) | Livestock products |
| land | Land pools |
| land_ag(land) | Agricultural land pools |
| n_pollutants_direct(n_pollutants) | subset of n pollutants |
| n_pollutants(pollutants) | subset of n pollutants |
| npk(nutrients) | Plant nutrients |
| pollutant_nh3no2_51(n_pollutants_direct) | nitrogen emissions relevant for deposition |
| pollutants(pollutants_all) | subset of pollutants_all that can be taxed |
| t_all(t_ext) | 5-year time periods |
| t_past(t_all) | Timesteps with observed data |
| t(t_all) | Simulated time periods |
| type | GAMS variable attribute used for the output |
Benjamin Leon Bodirsky
18_residues, 50_nr_soil_budget, 55_awms, 56_ghg_policy, 57_maccs, 59_som
Bodirsky, Benjamin Leon, Alexander Popp, Isabelle Weindl, Jan Philipp Dietrich, Susanne Rolinski, Lena Scheiffele, Christoph Schmitz, and Hermann Lotze-Campen. 2012. “Current State and Future Scenarios of the Global Agricultural Nitrogen Cycle.” Biogeosciences Discuss. 9 (3): 2755–2821. https://doi.org/10.5194/bgd-9-2755-2012.
IPCC. 2006. “2006 IPCC Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programme.”