Emission Mitigation

SimsDairy provides the opportunity to examine several emission mitigation strategies (greenhouse gas and other nitrogen emissions) for a dairy cattle farm and the size of this mitigation effect for this farming system.

An example, using realistic values, is provided in the MilKey platform in order to give information about the functionality and the results of the SimsDairy model regarding the effect of mitigation strategies on the emissions from a dairy cattle system in comparison to a reference scenario (baseline). Therefore, the results presented in this chapter of the MilKey platform are a product of simulations and they are not derived from real data acquired from the dairy cattle farming systems examined during the MilKey project. The results will be updated after the acceptance of a manuscript that has been submitted for publication.

The potential effect of various mitigation strategies to the contribution of these GHG emission sources to the total
GHG emissions, emitted N substances to the total N emissions, and N hotspots to the total N emissions of the dairy
cattle farming system can be shown in the following steps:

Check the mitigation practices that have been assessed: Each time the cursor is placed on a
mitigation practice (from the list below), the user is able to see a short description of this practice.
Click on the mitigation practice: The user is able to see the effect of the mitigation practice
on the contribution of the various sources to the total GHG emissions. This is done in comparison to the
relevant effect of the baseline scenario. The tables and the figures for the baseline and the mitigation
scenarios are simultaneously visible to the user, allowing an easier visual comparison of these results. A note
appears to the user explaining if the alternative scenario tested leads to higher or lower total GHG emissions
from the dairy cattle farming system.

The key features of the dairy production systems modeled in Table 1

The mitigation methods are presented in Table 2

Table 1

	Units	WCi	WOs	ECs	MCi	NCs	ACs

Location	–	Germany	Germany	Poland	Italy	Norway	Ireland
Production system	–	Conventional	Organic	Conventional	Conventional	Conventional	Conventional
Degree of intensi-	–	Intensive	Semi-extensive	Semi-extensive	Intensive	Semi-extensive	Semi-extensive
Average monthly	°C	12	11	9	14	7	10
Average monthly	mm	72	50	57	87	84	84
Soil texture	–	Sand	Sandy loam	Clay loam	Sandy loam	Clay Loam
Dairy animals	Animals	138	240	50	565	55	185
Total dairy live-	LU	184	304	83	956	91	236
Main cow breed	Name	Holstein	Holstein	Crossbreed^b	Holstein	Norwegian red	Crossbreed^c
Milk production	kg FPCM^a	11,194	7724	8898	9547	7865	5522
Milk yield	kg animal⁻¹day⁻¹	30.6	21.1	24.3	26.2	21.5	15.1
Forage-to-concen-	Ratio	60:40	80:20^d	80:20	50:50	60:40	90:10
Crude protein in	%	27	15	23	20	18	14
Silage type	–	Grass/maize	Grass/maize	Grass/maize	Grass/maize	Grass	Grass
Farm area (UAA)	ha	71	495	80	270	87	87
Surface grassland	%	55	44	71	46	86	100
Grazing time	Days	0	215	164	0	139	259
Slurry storage	Type	Crusted	Crusted	Rigid	Crusted	Rigid	Crusted
Slurry application	Type	Shallow injection	Band spreading	Broadcast	Broadcast	Broadcast	Shallow injection

WC_i Western European conventional intensive system
WO_s Western European organic semi-extensive system
EC_i Central-Eastern European conventional semi-extensive system
MC_i Mediterranean conventional intensive system
NC_s Northern European conventional semiextensive system
AC_s Atlantic conventional semi-extensive system
°C degrees centigrade, mm millimetres
LU livestock units
FPCM fat and protein corrected milk
UAA utilised agricultural area
CAN calcium ammonium nitrate
U urea
AN ammonium nitrate.
^astandardised to 4% fat and 3.3% protein per kilogram of milk (IDF 2015); ^bHolstein, Montbéliarde, and Polish red; ^cHolstein and Jersey;
^d20% of the diet composed by self-produced cereal mix (no concentrates bought); ^emore than one typology of mineral fertiliser is applied

Greenhouse gas (GHG) emissions
Nitrogen (N) emissions
Nitrogen emission hotspots

WCi

WOs

ECs

MCi

NCs

ACs

WCi

WOs

ECs

MCi

NCs

ACs

WCi

WOs

ECs

MCi

NCs

ACs

Mitigation methods	Acronyms
Diet management
Productive performance associated with a greater fraction of purchased feed	PI
Crude protein	CP
Slurry management and fertilizer application
High- efficiency covers on slurry storage	HESc
High- efficiency shallow injection	HESa
Urea substitution	Urea
Anaerobic digestion plant implementation	AD
Combined application
Two or more mitigation options were applied	Combined

	Baseline
kg CO₂-eq kg milk^-1
Enteric emissions	0.320
Manure emissions	0.213
Field emissions	0.026
Other source emissions	0.325

	HES_c
kg CO₂-eq kg milk^-1
Enteric emissions	0.320
Manure emissions	0.201
Field emissions	0.026
Other source emissions	0.325

	CP
kg CO₂-eq kg milk^-1
Enteric emissions	0.320
Manure emissions	0.200
Field emissions	0.022
Other source emissions	0.325

	AD
kg CO₂-eq kg milk^-1
Enteric emissions	0.320
Manure emissions	0.059
Field emissions	0.027
Other source emissions	0.310