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Annual Meeting 2010 Istanbul, 21-22 April Round Table Can agricultural investment coexist with climate change policies? Soil carbon sequestration Martial Bernoux April 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 Mt CO2equivalent per year 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* Global mitigation potential by 2030 (from Smith et al., 2007) * 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 Mt CO2equivalent per year Global mitigation potential for each region by 2030 (Extract from Smith et al., 2007) EastAgri countries represent mitigation potential of at least ~800 MtCO2-eq / year (i.e. ~14% of global potential) Global mitigation potential by 2030 (from Smith et al., 2007) Background Agriculture and Forestry are key sectors of Climate Change concerns presenting a dual aspect. …But with an important mitigation potential 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 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 through residues decomposition C inputs through root system 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 Conservation Agriculture 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 Soil carbon mineralization Decrease soil carbon stock Residues Increase soil carbon stock Conservation agriculture and Soil C sequestration Impact of adoption of conservation agriculture on soil carbon stocks Soil C accumulation Soil Carbon Conventional Agriculture Conservation Agriculture CA also promotes economy of fossil fuel consumption (permanent benefit) Adoption of Conservation Agriculture CA/No-tillage in the world in 2007/08 (million ha) Total World: ~110 Million ha Evolution of Global Area under Conservation Agriculture (Million Ha) Russia 2.0 * Canada 13.5 USA 26.6 Europe 1.1 120 100 Asia 2.5 80 60 40 20 Africa 0.4 - Paraguay 2.4 Other South America 2.0 Brazil 25.5 1983-1987 Argentina 19.7 Statistics from Derpsch and Friedrich, 2009 1988-1992 1993-1997 1998-2002 2003-2007 Australia 12.0 *Roberts and Johnston, 2009 Different forms of “no-tillage” Conservation Agriculture: a challenging definition Statistics are dependent of definition used: example from France CA official number for France: 150 000 ha (2003-2007) from FAO-CA site 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) % of plots with no-till Durum wheat (Triticum durum) Carbon sequestration rates for Conservation Agriculture Lal et al., 1995 - Semi-arid and subtropical: - Temperate: tCO2-eq ha-1 yr-1 0.15-0.7 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. 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/ How to promote agriculture investment in line with climate change policies Part of the solution is in our hands! Science has brought evidences…. Consumers already ask for products with low GHG impact …. Now…political decisions are also needed