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Alternative approaches to manage carbon sinks in small farm forestry: Mexico’s experience and methods Ben H.J. De Jong; El Colegio de la Frontera Sur (ECOSUR), Tabasco, México E-mail: [email protected] WORKSHOP ON FORESTRY AND CLIMATE CHANGE ASSESSING MITIGATION POTENTIAL: LESSONS LEARNED India International Center New Delhi; sept 23 & 24, 2002 Presentation: Brief outline of how project functions Project area Present status of the Scolel Té project C-sequestration potential of proposal without baseline Baseline: Afforestation Avoiding deforestation Monitoring: Pools Frequency Leakage: How is leakage treated Assessing level of error in leakage assumptions Project area Chiapas N 0 20 40 Kilometers Scolel Té communities Baseline area 2´800,000 ha Present Status: Sales of voluntary carbon offsets of the Scolel Té project Year Sales (tonnes carbon) Purchaser 1997 5,500 FIA (Formula One) 1998 5,500 FIA (Formula One) 1999 5,500 FIA (Formula One) 2000 6,573 FIA (Formula One), Future Forests 2001 9,297 FIA (Formula One and World Rally), Future Forests 2002 13,297 FIA Foundation (Formula One and World Rally), Future Forests Total 45,667 Example of Plan Vivo Number of participants, area committed, and tC purchased in two eco-regions of Chiapas, Mexico Tropics Coffee with shade trees Hectares Producers1 Potential (tC ha-1) Purchased2 (tC) 101 101 73 2,801 6 6 54 609 153 149 146 8,357 Green manuring 56 112 45 5,406 Improved fallow 89 81 146 3,635 3,000 3 100 3,000 47 13 137 3,588 214 192 102 9,492 3,665 657 Living fences Taungya Forest conservation Sub-tropics Forest restauration Improved fallow Total 1 2 36,888 Producers are either individual farmers or whole communities Difference between potential per ha and purchased due to baseline, part of carbon purchased and risk buffer Taungya with Cedrela odorata Calculation of C-sequestration potential: CO2FIX model approach Parameters used to estimate carbon fluxes in agroforestry systems in Chiapas, Mexico (from De Jong et al 1997). Parameters Tropics Sub-tropics 6 x 25 5 x 30 Initial humus content of the soil (MgC ha-1) 75 75 Basic Wood Density (kg m-3) 500 450 Carbon content (% of dry weight) 50% 50% Rotations (years) Dry weight increment relative to stem years after planting years after planting increment during one rotation: 0-10 10-20 20-25 0-10 10-20 20-30 Foliage 0.7 0.4 0.4 0.8 0.6 0.2 Branches 0.6 0.4 0.4 0.8 0.5 0.2 Roots 0.7 0.4 0.4 0.9 0.6 0.3 Turnover rates: Foliage 0.5 0.3 Branches 0.05 0.05 Roots 0.07 0.07 0.1 0.05 1 3 100 200 Humification factor Litter residence time (years) Stable humus residence time (years) Estimated yearly increment (CAI) of the tree components M 3/ Yr 30 TAUNGYA AND ENRICHED 20 FALLOW COFFEE WITH SHADE 10 LIVE FENCE 0 7 13 19 YEAR 25 tC/ha Flux outcome of Coffee with shade trees, according to production level I to III 140 120 Level III Level II 100 Level I Av-Level III 80 Av-Level II Av-Level I 60 40 20 0 0 25 50 75 100 125 150 Baselines - The carbon offset potential of any activity must be calculated relative to a baseline. The baseline describes the current status of carbon stocks or emissions and expected changes in the absence of the project - the so called 'business as usual' scenario. Reductions in emissions relative to the baseline may be claimed as carbon offsets. The construction of a baseline must be clearly described giving the sources of all information and a justification of any assumptions used. Sequestration – carbon stocks in existing vegetation and expected changes in land use. Current carbon stocks should be estimated through biomass surveys or using data in the literature. The expected change in land use should take account of prevailing socio-economic pressures in the region. Conservation – the expected rate of deforestation and the resulting carbon emissions. Setting baselines for forest conservation will require data on the carbon density of existing forest vegetation and an analysis of regional land-use trends. Approach used in the afforestation projects: Project = potential – initial carbon Some of the required data of the initial stage Plot Size : (ha) Orientation: N S E O Current use: Corn Shrub Fallow pasture 20 - 50cm 50 cm -1 m coffee Other Soil data: color: DEPTH CLASS 0 – 20 cm >1m Current vegetation: NOTHING FEW (<25%) HERBS SHRUBS SMALL TREES (< 5M) MEDIUM TREES (5-10M) LARGE TREES (10-20M) VERY LARGE TREES (>20M) MODERATE (25-50%) ABUNDANT (> 50%) Baseline reductions applied to an afforestation proposal in the tropics with varying amount of initial biomass, such as coffee with shade trees. (based on amount of C present at initial stage in the various pools) Note: C-density of each pool according to measured densities in forest and non-forest plots Deforestation baseline: Multi-project approach with construction of spatially explicit carbon risk matrices Objective: to develop a simple approach to spatially explain deforestation and associated carbon fluxes with various predisposing and driving factors. The outcome of the analysis could then to be used as a simple tool to estimate deforestation dynamics and associated carbon fluxes with readily available data sources, such as estimated population density and dynamics, development of infrastructure and other public services, among others, which in turn can be integrated in a multi-project baseline scenario that could offer readily available without-project carbon emission estimations in the future of any project within the study area. Land-use in the 1970s Land-use in the 1990s LU/LC Change between 1970s and 1990s Deforestation closed forest Deforestation disturbed forest Degradation closed forest Degradation disturbed forest Without change Slight increase in biomass Restored sec. vegetation Restored forest Spatial correlation between deforestation and various “predisposing” and “driving” forces. Spearman’s correlation coefficients between deforestation and causal factors of change Causal factor Slope gradient Distance to roads Distance to agriculture Population density Scarcity index ** Significant at 0.01 level * Significant at 0.05 level Study area 0.117 1.000** 0.997** 0.984** 0.886 * Highlands 0.900** 1.000** 0.988** 1.000** 0.829 * Cañadas 0.817** 1.000** 0.996** 1.000** -0.900 * Selva -0.650 1.000** 0.999** 0.927** 0.771 (Castillo-Santiago et al 2002) Relation between the predisposing factor “distance to agricultural fields” and driving factor “density of farmers”, and carbon emissions (in % of standing stock), including 95% confidence intervals Carbon flux in % of Stock 1.0% 0.9% Distance to agriculture 0.8% 0 - 500 m > 500 m 0.7% 0.6% 0.5% 0-2 2-5 5 - 10 10 - 20 Density of farmers (km-2) > 20 Carbon “risk” map, based on predisposing factor “distance to agriculture” and driving factor “ density of farmers” Risk categories 0.65% 0.70% 0.80% 0.90% Vegetation map of 1996 N 0 5 10 Kilometers Vegetation classes Closed forest Open-disturbed forest Secondary vegetation Open areas Overlay of carbon risk map and 1996 vegetation map Sum of Vulnerable C in each risk-cell Example baseline emission estimation (Applying lower limit of 95% Conf. Int.) Distance to agric. > 500 m 0 - 500 m farmers 0- 2 2- 5 5 -10 tC 21,923 33,255 1,554 30,386 23,906 844 Accumulated baseline emission estimations for Juznajab la Laguna, Chiapas, Mexico 20000 15000 10000 5000 0 0 5 10 15 20 Year Monitoring indicators The technical specification details how the production of carbon offsets will be monitored. Monitoring indicators are based on easy to measure variables relating to the management requirements given in the technical specification and the associated changes in carbon stocks/emissions. For example: •Sequestration - Measurements of planting density (only once), survival rates (% of total) to define replanting necesities, and tree diameter and height after reaching minimum size (measurements based on sampling). •Conservation - Monitoring of forest conservation will include periodic measurements of forest cover, and monitoring indicators relating to sustainable forest management (establishment of fire breaks, establishment of institutions to regulate forest use, implementation of activities designed to reduce pressure on forest resources etc.) may also be used. A monitoring template is included in each technical specification to indicate which data to record. Monitoring guidelines for coffee with shade trees (Cedrela odorata) Decision tree to select C pools (Based on Sathaye and Ravindranath 1997) Emission Capture Direction of change Large Small Size of pool Fast Slow Fast Rate of Change Include pool Slow Rate of Change To be considered Possible criteria: •Cost •Development of measuring methods •Modelling with verified data Do not include pool Types and causes of leakage that could occur in the Scolel Té project (Typology according to Aukland et al 2002) Types of leakage Causes of leakage Activity shifting Activities that cause emissions are not permanently avoided but displaced to another area. Outsourcing Farmers purchase or contract out of the commodities and services previously provided on-site, thus shifting the responsibility for the activity to another party. (eg. Selling or renting the land where the trees are planted) Super-acceptance The carbon-emitting activity in the non-project area of the participating party changes faster (negative leakage) or slower (positive leakage) than predicted by the baseline, such as when participating and non-participating farmers start forestation activities on non-project land without carbon subsidies. C-sequestration systems and alternative livelihood activities C-sequestration activity Alternative livelihood activity to avoid leakage Coffee with shade trees No change in productivity expected, no need for alternative livelihood activity Living fences No change in productivity expected, no need for alternative livelihood activity Taungya Permanent corn production through combination of corn with green manure in project and non-project area, to avoid deforestation in remaining non-project area Improved fallow Permanent corn production through combination of corn with green manure in project and non-project area, to avoid deforestation in remaining non-project area Natural regeneration in abandoned pasture Improved pasture with high quality fodder species in non-project area, to avoid a shift in grazing to non-project community forests Risk Buffer The risk buffer is a reserve of unsold carbon credits. The aim is to allow the Carbon Fund to cover any unexpected shortfall in carbon credits supplied to purchasers. The project operational manual justifies the size of the risk buffer and state how it is maintained. The size of the risk buffer is determined by the risks associated with carbon credits sold via the Carbon Fund, for example: •Loss of sequestered carbon due to fire in forestry projects •Producers failing to maintain offset activities for specified timeframes •Inaccuracies in carbon modelling or baseline assumptions The Scolel Té project maintains a risk buffer of 10% of carbon sold via the project. Thank you More info: www.planvivo.org E-mail: [email protected]