1. Emissions from land use change and soil
carbon changes in carbon footprints of
animal products
Christel Cederberg and Stefan Wirsenius
Department of Energy and Environment, Chalmers
SIK, the Swedish Institute for Food and
Biotechnology,
KSLA 24 May 2013
Chalmers University of Technology

2. Increased competition over land
Production of livestock products
- ~75% of global agricultural land
- FAO:s global meat consumption to
double by 2050
New climate policies? –
more expensive to emit
fossil CO2
...will lead to increased demand for
biomass for energy production

3. Outline
• CO2-emissions from Land Use Change – case
Brazilian beef
• Emissions/sequestration from Land Use
• Including land-related emissions and
sequestration in GHG estimates of animal
products

4. Land use impacts
Transformation impacts Occupation impacts
Land use change (LUC) –
emissions of CO2

5. CO2 emissions from fossil fuels and
Land Use Change, LUC
Datasources:Marlandetal.(2007)forfossilfueluseand
Houghton(2008)forlandusechange.
0
2
4
6
8
10
1850 1900 1950 2000
GlobalCO2emissions(GtC/yr)
Land use change - the tropics
Land use change - restofthe world
Fossil fuel use & cementmanufacture

6. Calculating C emissions from LUC – case Brazilian beef
CH4 CO2 N2O
MATERIALS
- Diesel
- Fertiliser
- (Pesticides)
- (Medicine)
FEED
- Mineral feed
- Comple-
mentary feed
BEEF
CO2
Feed Manure
BEEF LIVESTOCK
PASTURE LAND
NATIVE FOREST
Land use change: pasture expansion
Source: Cederberg et al 2011. Env Sc & Tech 45:1773-1779

7. Typical cycles of land use after
deforestation in the Brazilian Amazon
Based on figures in: Ramankutty et al (2007) Global Change Biology 13, 51-66

8. Year 1 Year 2 Year 3 Year 4
PASTURE
+ + + ......?
........?
GHG emissions caused by Direct Land Use Change
CO2 over
several years
After x years are some of the
land abadonned – regrowth of
forest mostly

9. Amazon forest transformed to pasture
• Total LUC emissions 612 ± 212 ton CO2e/ha
• High uncertainty! Mostly due to uncertainties
in carbon content of the original forest
• Distributing 6% of biomass to timber products
removed before burning the forest
• Distributing emissions from agriculture
products (beef) 572 ± 198 ton CO2e/ha
• Amortize emissions over 20 years

10. Export
Beef export mostly
from non-
deforestation states
0
2 000
4 000
6 000
8 000
10 000
1997 1999 2001 2003 2005
1000tonCWE
Total production
Domestic consumption
Exports

11. GHG emissions from Brazilian beef and EU beef
2011-04-01
EU Sweden Brazil
LUC
no LUC Total Amazon Direct 20 yrs
CO2 from fossil
fuels
3.3 2.2 0.3
Methane (CH4) 10.1 12.5 21.6
Nitrous oxide
(N2O)
9.1 5.1 6.3
LUC - - - 44 180 726
Total 22.5 19.8 28.2 72 208 754
System boundary?
Total: LUC emissions distributed total beef production
Amazon: LUC emissions distributed over beef production in Amazon region
Direct 20 yrs: LUC emissions only on beef production on the pastureland
deforested the last 20 yrs

12. Carbon credit for biofuels versus carbon
emissions from land use change
Growing feedstock for biofuels
remove CO2 from atmosphere
Growing feedstock for biofuels means a
direct and/or indirect carbon cost
By excluding LUC-emissions, analyses of biofuels are one-sided because
they used only the carbon benefits of using land but not the carbon costs
by diverting land from its existing use (Searchinger et al 2008)

13. Economic equilibrium modelling to estimate
indirect land use change from biofuels
Increased demand, crop A
Reduced
demand,
crop A
Intensified
production,
crop A
Cultivation of
crop A on
previous non-
agricult land
Crop A replaces
crop B
Reduced demand
crop B
Intensified
production crop
B
Cultivation of
crop B on
previous non-
agr land
Crop B
replaces crop
C
Etc…………
Price increase

14. Estimates of indirect land use
emissions from biofuels vary wildly
Reference Year LUC impact,
gram
CO2e/MJ fuel
Net impact of
biofuel
consumption when
incl LUC, g
CO2e/MJ
Searchinger et al 2008 156-270 127 to 232
EPA (US Renew Fuel Standard 2009 106-130 41 to 52
CARB (California Low Carb Fuel
Standard
2009 44-68 15 to -13
Tyner 2009 36 8
EPA final 2010 8-54 -4 to -69
Hertel et al 2010 40 10
Tyner et al 2010 21-32 1 to -9
IFPRI (EU comm) 2010 17 -43
European Commission 2010. The impact of land use change on greenhouse gas emissions from biofuels and bioliquids. Literature review

15. Important problems with data and
methodology when assessing LUC
• D: Areas deforested and initial
Carbon stock
• D: land use after LUC
• M: Amortisation period
• M: DLUC ok with above data but
• M: ILUC – requires complex
modelling including land use
and trade of agr and biofuel
products

16. Land use impacts
Transformation impacts Occupation impacts
Land use (LU)
CO2-emissions/C-sequestration?

17. Verifying soil carbon changes
BASELINE
Arable land, stock
75 ton C/ha
(0-25 cm)
25 cmACTION
We do a new management
activity, positive for C-seq
binding 400 kg C/ha*yr.
We do this for 25 yrs
Time factor important!
Efter ett år är ökningen
0,5%, dvs mycket liten,
svårt att mäta med
jordprov
After 25 yrs C-stock has
increased by 10 ton C/ha to
85 ton C/ha.
This can be measured
400 kg C/ha*yr = ca 1,5 ton CO2/ha*yr.
Diesel 80l/ha emits ca 250 kg CO2/ha *yr

18. C-TOOL –
3-pooled dynamic soil carbon
model

19. Important parameters for estimating
soil carbon changes
• Carbon input
– crop residues
– Organic material (e.g. manure)
• Initial carbon stock in soil
• Temperature
• Clay content
• Water content
• Carbon/Nitrogen ratio
• Tillage(?)

20. Carbon in harvest products and crop
residues
-8
-6
-4
-2
0
2
4
6
C in
harvest
C in crop
residues
Ton
C/ha

21. Dairy case study -
Västra Götaland region Baseline
Maize &
grass More grass
Kg DM per cow*yr
Grass/clover
silage,
pasture 3 367 1 601 4 499
Maize silage 549
Super-
pressed pulp 427
Grain 1 409 1 582 876
Concentrates 1 314 1 383 645
Total 6 090 5 542 6 020
-
- Comparison three
feed rations for dairy
cows producing 9000
kg milk/yr
- Soil carbon changes
for the three rations
were estimated using
C tool
Feed rations according to Liljeholm et al, 2009

22. Milk and beef can be produced with different
feed rations…..effects on soil carbon changes?
0,00
0,10
0,20
0,30
0,40
0,50
0,60
0,70
0,80
Baseline Maize & grass More&Better
Grass
kgDMfeedperkgmilk
Concentrates
Grain
Super-pressed pulp
Maize silage
Grass/clover silage, pasture
Production level
9000 kg
milk/cow*year
Wirsenius & Cederberg, ”Soil carbon sequestration as a greenhouse gas mitigation option in dairy
production”, manus in prep

23. Land occupation,
m2 per kg milk and year
0
0,2
0,4
0,6
0,8
1
1,2
1,4
1,6
1,8
Base Maize More grass
Sce I Sce II Sce III
m2perkgmilkandyear
Other
By-prod sugar industry
Soymeal
Rapeseed meal
Grain
Maize
Grassland

24. Experiences from modelling soil C changes for
different feed rations in milk production
• Initial soil carbon status is very important for the
soil´s carbon sequestration potential
• The estimated soil carbon changes are significant,
but not of great importance for milk´s total GHG
balance
• Feed rations with maize seem to loose soil carbon
• Feed rations with maize tend to have lower land
requirement – how is “surplus” land used?
• Reasonably correct data on crop residues from
grasslands needed – lack of data!

25. Thank you!