presentación Keynote en el workshop REMEDIA 2012 sobre reducción de gases de efecto invernadero en el sector agroforestal

1. Bilbao, March 8, 2012
How can we manage Europe’s
terrestrial greenhouse gas balance?
Jean-François Soussana

2. Outline
1. Context: climate negotiations and food security
2. International and European research programing
3. The land based carbon and GHG balance of Europe
4. Comparing arable, pasture and forest systems
5. GHG balance of grazing systems
6. The GHG balance of farms
7. Vulnerability to climate change

3. Agriculture, Forestry and Land Use (AFOLU)
account for one third of global greenhouse gas emissions
89 % of the global technical mitigation potential in agriculture
would be through soil carbon sequestration (IPCC, 2007)

4. Lifecycle analysis of products leading
to GHG emissions and removals
Cross-sectoral and cross-boundaries view

5. Climate negotiations
• In 2007, the EU commited to an overall 20 %
reduction in GHG emissions in 2020 (compared
to 1990)
• Agriculture is committed to a 10 % reduction with
variable share of efforts across countries
• Modest progress in the UN climate negotiations:
International exchanges of views (SBSTA) on
the role of agriculture have been decided in
Durban

6. Livestock, a threat to climate
Livestock emits: 1/3 of anthropogenic CH4 (enteric fermentation)
2/3 of anthropogenic N2O, the great majority from manure
9 % of anthropogenic CO2 (deforestation) (FAO, 2006)
Global production of meat and milk are projected to more than double by 2050
Food labels in some countries providing carbon ‘footprints’

7. (J Delincé, 2011)

8. (from Tara Garnett, Food Climate Research Network, UK)

9. Role of food habits
DUALINE
Poor food habits could lead to lower GHG emissions for women (not for men)

10. Outline
1. Context: climate negotiations and food security
2. International and European research programing
3. The land based carbon and GHG balance of Europe
4. Comparing arable, pasture and forest systems
5. Vulnerability to climate change
6. The GHG balance of farms

11. Global Research Alliance
Livestock Research Group
Croplands Research Group
Paddy Rice Research Group

12. Joint Programing in Research
Agriculture and Climate Change
(FACCE JPI)
www.faccejpi.com 12

13. FACCE-JPI
Scoping Mitigation
National
National
inventories
inventories
MRV
MRV
Storylines,
Storylines, ICOS,
ICOS,
Policy options
Policy options inventories
inventories
Conceptual
Conceptual
Framework
Framework
LCAs
LCAs
Technical
Technical Consumer
Consumer
measures
measures behaviours
behaviours
Farming
Farming
Systems,
Systems,
Land use
Land use

14. ICOS – Infrastructure for a
Carbon Observation System

15. ANAee
Analysis of Ecosystems
A large European infrastructure on (agro) ecosystems

16. AnimalChange (FP7)
Global and regional livestock storylines and scenarios under climate
change
Detailed assessment of mitigation and adaptation options for Europe, Brasil
and three regions in Africa
Technical potential, economical potential, barriers to implementation
Field, animal, farm and regional scale modelling

17. EC FP7 ANIMALCHANGE partners

18. Direct GHG emissions from livestock
2.8
Animal food and GHG emissions
2.6
2.4 Animal food
Direct GHG emissions from livestock
Direct GHG emissions per unit animal food protein
2.2
Standardized data
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
1960 1970 1980 1990 2000 2010 2020
Year

19. Direct GHG emissions per unit food protein
GHG per animal protein
Mean GHG per food protein
GHG per plant protein

20. Outline
1. Context: climate negotiations and food security
2. International and European research programing
3. The land based carbon and GHG balance of Europe
4. Comparing arable, pasture and forest systems
5. Vulnerability to climate change
6. The GHG balance of farms

21. Towards a full accounting of GHG fluxes
from agriculture, forestry and land use?
• Inventories • Unknowns
– CH4: enteric – How do emission
fermentation; manure factors vary?
management – Is there a role of
– N2O: agricultural soils; climatic variability?
manure management. – Are soils sources or
– Forest carbon stock sinks of carbon under
changes constant
management?
– Soil C stock change
through land use
change and => Improve scientific
management understanding

22. Land and oceans store carbon
Large interannual
variability in global
land C sink
(Canadell et al.,2007, PNAS)

23. An assessment of the continental carbon
balance of Europe
1000 km
Upscaling 10 km
Prediction
ha
Downscaling
dm
µm Verification
CarboEurope IP
Funded and coordinated by
the European Commission
DG XII Research

24. Land based carbon sequestration
in Europe (2000-2004)
UNCERTAINTY
(Schulze et al., Nature Geosciences, 2009)

25. Land based greenhouse gas balance in
Europe including C sequestration
UNCERTAINTY
* CH4 and N2O fluxes are expressed as carbon in CO2-equivalents with a greenhouse
warming potential of 100 year horizon
(Schulze et al., Nature Geosciences, 2009)

26. Summary of the continental
greenhouse gas balance for EU 25
• The land surface sink reaches -111 Million
tonnes of carbon per year, which is 11% of
the CO2 emitted by fossil fuels.
• However, since the emissions of methane
and nitrous oxide are relatively higher in the
European Union the land surface emerges as
a greenhouse gas source of 34 Million tonnes
of carbon per year.
• This effectively increases the emissions from
fossil fuel burning by another 3%.
(Schulze et al., Nature Geosciences, 2009)

27. Outline
1. Context: climate negotiations and food security
2. International and European research programing
3. The land based carbon and GHG balance of Europe
4. Comparing arable, pasture and forest systems
5. Vulnerability to climate change
6. The GHG balance of farms

28. Ecosystem flux measurements

29. Simultaneous
measurements
of CO2 and H2O
exchanges

30. Components of a managed ecosystem
carbon budget
NEE: Net Ecosystem Exchange, balance
NBP: Net Biome Productivity, C Atmospheric C balance

31. The balance between gross photosynthesis (GPP),
plant (Ra) and soil organism (Rh) respiration
in contrasted European ecosystems
Sink Source GPP
Ra
Rh
Cropland
Grassland
Forest
C balance: NEP
-1500 -1000 -500 0 500 1000 1500
-2 -1
g C m yr (After Schulze et al., Nature Geosciences, 2009)

32. The balance between carbon and other greenhouse
gases in contrasted European ecosystems
Sink Source
Cropland
Grassland
NEP
Harvest
Forest Manure
Fire
DOC/DIC
GHG balance Other GHG
-400 -300 -200 -100 0 100 200 300 400
g C m-2 yr-1
(After Schulze et al., Nature Geosciences, 2009
& Siemens et al. Global Change Biology, in press)

33. Dissolved organic C leaching
(Kindler et al., Global Change Biol., 2011)

34. EU25 terrestrial greenhouse gas
balance* including C sequestration
GHG balance of agriculture in EU25 including C sequestration
Forest biomass
Forest soil
Grassland
Cropland SINK SOURCE
Peatlands
Land use change
Carbon trade balance
Carbon to rivers and seas
Fossil fuel agriculture
CH4 agriculture
CH4 wetlands
N2O agriculture
GHG flux
-150 -100 -50 0 50 100 150
Megatons C per year
* CH4 and N2O fluxes as carbon in CO2-equivalents with a GHG warming potential of 100 year horizon

35. The GHG balance of the
agriculture sector in Europe
GHG balance of agriculture in EU25 including C sequestration
N2O
CH4 agriculture
Fossil fuel agriculture
Drained peat
Cropland
Grassland
-40 -20 0 20 40 60 80
Mt C yr-1
Grassland C sequestration would play a significant role for the
European agriculture sector
(After Schulze et al., 2009 Nature Geosciences)

36. Outline
1. Context: climate negotiations and food security
2. International and European research programing
3. The land based carbon and GHG balance of Europe
4. Comparing arable, pasture and forest systems
5. Carbon balance of grasslands
6. Vulnerability to climate change
7. The GHG balance of farms

37. The C balance of
a grassland
ecosystem NEE
(NBP)
Carbon balance (Net Biome Productivity) :
NBP = (NEE - FCH4-C) + (Fmanure - Fharvest – Fanimal-products) – Fleach
(Soussana et al., 2010, Animal)

38. C sequestration in a temperate pasture
(tC ha-1 yr-1)
CH4 Herbivore CO2
respiration Gross primary
0.2 2.1 19 productivity
Herbivore Grazing Vegetation
Végétation
3 7
+0.05 0 Shoot
0.7 Animal respiration
excreta Root turnover
Rhizodeposition 9
Litter
Soil
9.2
Soil C sequestration: +0.5 Below-ground
respiration
DOC, DIC ?
Sown grassland with intensive grazing (Soussana et al., Soil Use Manag., 2004)

39. Carbon sequestration (NBP) at 10
European grassland sites
Carbon sink
-
Carbon source
-
• The less carbon is used, the more is returned to the soil,
which increases C sequestration
• Nitrogen supply also favours carbon sequestration
(Soussana et al. Agriculture, Ecosys. Environment, 2007)

40. Disturbance induced changes in C cycling
(Klumpp, Falcimage & Soussana, 2007, AGEE; Klumpp, Soussana & Falcimagne, 2007, Biogeosciences)
Soil C sequestration
Grassland mesocosm experiment
(g C m-2 yr-1)
) A trade-off between aboveground
production and belowground C sequestration Cutting
disturbance
i) Disturbance reduces mean residence time of C Above-ground net primary
n soil fractions >200 µ productivity (g C m-2 yr-1)
Compressor
MRT= 22 month
Cutting
CO2 scrubber disturbance
MRT = 31 month
Steady state 13CO2 labelling

41. Separating direct role of disturbance
from plant traits: Response & Effect
C sequestration (gC m-2)
b2, direct
disturbance
effect
aE2, trait mediated
effect
Root density
(Klumpp & Soussana, Global Change Biol., 2009)

42. Disturbance increase: a cascade of effects.
Disturbance
5. Change in plant species
1. Photosynthesis and root composition
biomass declines
2. Decline in fungi and 4. Increase in N available
increase in Gram+ bacteria for plants and in
0.60
aboveground production.
Fraction of total PLFA
1.0
0.50
LL
0.40 0.8
fungal LH
gram-
0.30 0.6
gram+
NNI
0.20
0.4
0.10
LL LH 0.2
Disturbance treatment 2.5
0.0
LL
2.0 LH 2003
a a
mg C g-1 soil
a
fPOM old
1.5 a
1.0 b
b a
0.5 b
3. Acceleration of unlabelled 0.0
POM decomposition 0 5 10 15 20 25
Month after start of 13C labelling
Klumpp, Fontaine, Soussana, Journal of Ecology (2009)

43. Climate x management interactions for
0.1
80
Reco (gC m ² week )
-1 c.
60
annual C sequestration
-
40
20
0 Extensive management sequesters more C in wet
-20 years, but is less resilient to drought than intensive
GPP (gC m ² week )
-1
I nt ensive -40
plot Ext ensive plot
management:
High st ock ing densit y : 1 LSU ha - 1 Low st ock ing densit y: 0.5 LSU ha -1
-
-60
N, P, K fer t iliser No f er t iliser supply
Extensive: higher LAI and ET, less available N.
-80
d.
-100 Laqueuille site, INRA
100
Cumulative NEE (gC m-²)
0
SOURCE
-100
-200
-300
-400 SINK
e. Summer droughts
-500
1000
f. Water fluxes
800
Latent Heat (W m )
-2
600
400
200
0
250 2003 2004 2005 2006 2007 2008
g.
200 (Klumpp et al., Global Change Biol., 2011)

44. Annual C balance of 28
grassland sites
C source C sink
(n=110 site years, mean ± s.e)
21 sites out of 28 were, on average, C sinks for the atmosphere
Leaching of dissolved carbon (DOC, biogenic DIC, 4 sites): 29 gC m -2 yr-1 (Kindler et al., 2011, GCB)

45. Simple C cycle model (5 state variables, 3 soil parameters)
Ecosystem respiration, Reco
GPP Ra Rh-animal Rh-litter Rh-active Rh-slow
(1-K1)GPP
(d+k CH4)Cintake
f(T,P) (1-K2) f(T,P) (1-K2) K2 f(T,P) kslow
Cplant Clitter Cactive Cslow Cpassive
1 f(T,P) K2 f(T,P) K22 f(T,P) kstab
Cintake (1-d-kCH4)Cintake Measured
Cexport Cimport
Modelled
(Soussana et al., in preparation)

46. Best fit for turnover of slow C
Turnover rate (Kslow) of slow
C declines with N availability
This is consistent with the
priming effect and is not
accounted for by classical
soil models.
n=15, r2 = 0.81, P< 0.0001

47. Simulated vs. measured
annual C sequestration
C balance is inferred from GPP, climate, management and soil texture

48. Carbon and GHG balance of grazing
systems (grassland and farm buildings)
At barn
FN2O FCO2 FCH4 Fanimal-products FCO2@barn Fanimal-products@barn
FCH
4@barn Flabile C losses
290 5 5
98 9 47
Fharvest
FN2O Fmanure@barn 43
237
83
Fmanure IPCC, Tier 1
17 17
NCS = 50 NCS@barn = 23
10
Attributed NCS = 73 (gC m-2 yr-1)
Fleach
Extensive pastures (n=3): 320 gCO2 equivalents m-2 yr-1 (sink)
Intensive meadows (n=3): -272 gCO2 equivalents m-2 yr-1 (source)
(Soussana et al., 2007, AGEE; Soussana et al., 2010, Animal)

49. Carbon balance of EU grazing systems
(1987-2007)
1.0
0.9
Cumulated relative frequency
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
-250 -200 -150 -100 -50 0 50 100 150 200 250 300 350
-2 -1
NBP (gC m yr )
Source Sink
Source Sink
(permanent grasslands) (Soussana et al., in preparation)

50. Greenhouse gas balance of EU grazing
systems (1987-2007)
IPCC Tier 1
For CH4 and N2O
(permanent
grasslands)
Sink CO2 equivalents Source

51. Outline
1. Context: climate negotiations and food security
2. International and European research programing
3. The land based carbon and GHG balance of Europe
4. Comparing arable, pasture and forest systems
5. The GHG balance of farms
6. Vulnerability to climate change

52. Mitigation options in New Zealand
(Ag-Research, NZ)

53. Marginal Abatement Cost Curves
(Moran et al., 2011, J. Agric. Economics)

54. A model of GHG and C sequestration
in livestock farms (FARMSIM)
Gaseous losses Fixation Atmospheric Gaseous losses
Lifecycle (C, N) (C, N) deposition (N) (C, N) IPCC
analysis Tier 2
Inputs
Cattle
housing
Energy
Feed
Animals Manure Animal
& straw produce
Feed & bedding stores
stores
Pastures
Fertilizer Meadows
Arable Crop
Seed
crops produce
Irrigation (N) Runoff (C, N) Leaching (N) Grassland and
crop models
A dynamic model coupling lifecycle analysis and carbon sequestration
(Salettes et al., 2004; Schils et al., 2007; Duretz et al., 2009)

55. Summary: greenhouse gas balance per unit area
of grasslands and of livestock farms
SINK SOURCE

56. Outline
1. Context: climate negotiations and food security
2. International and European research programing
3. The land based carbon and GHG balance of Europe
4. Comparing arable, pasture and forest systems
5. Carbon balance of grasslands
6. The GHG balance of farms
7. Vulnerability to climate change

57. Did the 2003 European heatwave
lead to a CO2 concentration?
Summer temperature anomaly Vegetation anomaly in July 2003
(July 2003, MODIS)

58. Net Primary Productivity change in 2003
vs. 1998-2002
Summer Annual
On average, the 2003 heat spell, combined with the drought, caused a
195 and 77 gC m-2 yr-1 decline in ecosystem photosynthesis and
respiration, respectively.
(Ciais et al., Nature 2005)

59. Possible knock-on effects of extreme
climatic events
Heat
Heat
Drought
Drought
Reduced GPP,
Reduced GPP,
Xylem embolism
Xylem embolism
Reduced reserves
Reduced reserves
Frost damage
Frost damage
Reduced foliage
Reduced foliage
Pests and insects damages
Pests and insects damages
Tree mortality
Tree mortality
Increased C Forest decline, Wildfires
Forest decline, Wildfires
losses
Change in land use: forest Misadaptation?
Change in land use: forest
to fallow or rangeland
to fallow or rangeland

60. Impacts of climate variability and
extremes on the C cycle in grasslands
Interannual variability
Agricultural Greenhouse gas
management emissions

61. What are the impacts of summer
heat and drought extremes?
C, control
CX, Control and extreme
(‘summer 2003’ heat wave)
T, average year in the 2050’s
TX, extreme year in the 2050’s
Automated rain shelters
Passive IR Active regulated IR

62. End of heat wave Two months after heat wave
Mediterranean
C
Medly
Dactylis glomerata
T
C
Temperate
Ludac
T
+ X - X + X - X

63. Concluding comments (1/2)
1. Soil carbon needs to be accounted to achieve a consistent GHG
balance in the agriculture, forestry and land use sector
2. Forestry has attracted more efforts so far, but is vulnerable to climate
extremes (e.g. storms, fires and droughts)
3. Soil carbon sequestration requires advanced verification methods,
which are still lacking in real farm conditions
4. There are multiple trade-offs between agricultural production, carbon
sequestration and N2O and CH4 emissions. Agricultural systems will
need to be gradually optimized in each European region.
5. Mitigation strategies could be based on the eco-efficiency of farms,
that is their net GHG emissions per unit of food, feed or fiber product.
6. Uncertainties scale up with the length of the food supply chains. There
is no consensus yet on lifecycle analyses for long supply chains like
livestock production.

64. Concluding comments (2/2)
7. Carbon sequestration should be sustained over several
decades to be effective.
8. Therefore, mitigation and adaptation to climate change need
to be addressed consistently
9. In addition, there are trade-offs between mitigation,
adaptation, food security, land use and biodiversity.
We try to address these multiple constraints