Annual Meeting 2010 Istanbul, 21-22 April
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Transcript of Annual Meeting 2010 Istanbul, 21-22 April
Annual Meeting 2010Istanbul, 21-22 April
Round TableCan agricultural investment coexist with climate change policies?
Soil carbon sequestration
Martial BernouxApril 22, 2010
Functionnal Ecology & Biogeochemistry of Soils & Agro-ecosystems
Background
Agriculture and Forestry are key sectors of Climate Change presenting a dual aspect.
Responsible for ~ 1/3 of total direct GHG emissions
…But with an important mitigation potential
Global mitigation potential by 2030 (from Smith et al., 2007)
About 89 per cent of this potential can be achieved by soil C sequestration through cropland management, grazing land management, restoration of organic soils and degraded lands, bioenergy and water management*
Mt CO2equivalent per year
* From UNFCCC Technical paper: Challenges and opportunities for
mitigation in the agricultural sector, 2008
Background
Agriculture and Forestry are key sectors of Climate Change concerns presenting a dual aspect.
Responsible for ~ 1/3 of total direct GHG emissions
…But with an important mitigation potential
Global mitigation potential by 2030 (from Smith et al., 2007)
Mt CO2equivalent per year
EastAgri countries represent mitigation potential of at least
~800 MtCO2-eq / year(i.e. ~14% of global potential)
Global mitigation potential for each region by 2030 (Extract from Smith et al., 2007)
Part of this potential is attainable at “low” or even negative cost
Background
Agriculture and Forestry are key sectors of Climate Change concerns presenting a dual aspect.
…But with an important mitigation potential
Background
Agriculture and Forestry are key sectors of Climate Change concerns presenting a dual aspect.
…But with an important mitigation potential
Currently this potential is mainly developed in the forestry sector for several reasons but mainly:
- Easy and low cost to monitor- Under the Kyoto Protocol: only afforestation/reforestation
projects are eligible under the Clean Development Mechanism
However, mitigation potential of agricultural soils is gaining acceptance and projects are being developed worldwide
- Under voluntary markets such as the BioCarbon fund, the CCX…- Canada, Portugal, Spain and Denmark already elected cropland
activities to officially account for soil C sequestration under the KP- Discussions in the climate negotiations on REDD plus- Development of tools for ex-ante appraisal of C-Balance (FAO, GEF…)- Development of analytical solution for field C determination
How Soil Carbon sequestration Works
C inputs throughroot system
C inputs through residues decomposition
C stock is the result of the balance of: •Inputs •Output (mineralization)
It is thus necessary to implement best management practices that would increase the inputs or/and decrease the outputs in order to
promote soil C sequestration
Example of soil management practices which increase soil carbon
Suppression of the burning (harvest residues…)
Improve soil fertility and plant biomass production
Improve management:Reduce/no tillage and/or cover crop/mulch
Soil carbon mineralization
Decrease soil carbon stock
Increase soil carbon stock
Residues
Conservation agriculture definition (FAO):1. Minimal Soil Disturbance: the disturbed area must be less than 15
cm wide or 25% of the cropped area (whichever is lower). No periodic tillage that disturbs a greater area then the aforementioned limits.
2. Soil cover: Ground cover must be more than 30%3. Crop rotation: Rotation should involve at least 3 different crops.
However, monocropping is not an exclusion factor
Conservation Agriculture
Soil CarbonSoil Carbon
ConventionalAgriculture
ConservationAgriculture
Soil Caccumulation
Conservation agriculture and Soil C sequestration
Impact of adoption of conservation agriculture on soil carbon stocks
CA also promotes economy of fossil fuel consumption (permanent benefit)
USA26.6
Canada13.5
Australia12.0
Europe 1.1
Brazil25.5
Total World: ~110 Million ha
CA/No-tillage in the world in 2007/08 (million ha)
Argentina19.7
Paraguay 2.4
Other SouthAmerica 2.0
Africa0.4
Asia 2.5
Statistics from Derpsch and Friedrich, 2009
Russia 2.0 *
*Roberts and Johnston, 2009
Adoption of Conservation Agriculture
Evolution of Global Area under Conservation Agriculture (Million Ha)
-
20
40
60
80
100
120
1983-1987 1988-1992 1993-1997 1998-2002 2003-2007
CA official number for France: 150 000 ha (2003-2007) from FAO-CA site
Different forms of “no-tillage”Conservation Agriculture: a challenging definition
Statistics are dependent of definition used: example from France
France published in 2007 a review of “non-inversion tillage methods”
Those techniques were used on a third (4.6 Mha) of the total arable area in 2005
They are being implemented throughout France, regardless of crop and soil type
Common (bread) wheat(Triticum aestivum)
Durum wheat(Triticum durum)
% of plots with no-till
Lal et al., 1995 tCO2-eq ha-1 yr-1
- Semi-arid and subtropical: 0.15-0.7- Temperate: 0.35-1.8
Six et al., 2002- Temperate and some Tropical (0-30 cm): 1.1 ± 0.4
Bernoux et al., 2006- (Brazil) tropical and subtropical (0-40 cm): 1.4 to 6.2
Area of CA in Brazil is forecasted to reach 40 Mha in 2020, Cerri et al.(2010) calculated that this will correspond to an additional mitigation of 140 Mt CO2-eq in 2010-2020, with 7 Mt CO2-eq corresponding to avoided emission from fossil fuel.
Carbon sequestration rates for Conservation Agriculture
CA: Benefits and Adoption Obstacles
Benefits of conservation agriculture:• Increased soil organic matter and fertility• increased profitability by reducing costs for soil preparation• possibility to have two crops in warmer climates
Obstacles to adoption:• Challenging technological changes• challenges to manage weeds• increased cost for herbicides (at least initially)• challenges to update farm machinery• difficulty to handle crop residues
These challenges make adoption easier in larger farms, and more challenging (but not impossible or even less beneficial) in smaller farms. That is why adoption takes time
How to promote agriculture investment in line with climate change policies
There is a lack of tools that would help project designers to integrate significant climate response activities in agriculture development projects.
Investments in such activities would received due attention at project development stage if justified by reasonable carbon ex-ante appraisals
FAO developped EX-ACT (Ex-Ante Carbon-balance tool) to help Assessing potential mitigation benefits of agricultural investment projects
• Set of linked Microsoft Excel sheets (19)
• Based on land use and management practices
• Using IPCC default values (Tier 1) and ad hoc coefficients (Tier 2)
• Measures C-balance with/without project
http://www.fao.org/tc/tcs/exact/events/en/