Quantification of soil N 2 O emissions from biofuel feedstock cultivation the Global Nitrous Oxide Calculator (GNOC)

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1 International Workshop Greenhouse Gas Emission from Oilseed Rape Cropping and Mitigation Options 4./5. March 2015 Thünen Institute, Braunschweig Quantification of soil N 2 O emissions from biofuel feedstock cultivation the Global Nitrous Oxide Calculator (GNOC) Renate Koeble (Adrian Leip, Robert Edwards, Luisa Marelli) External Consultant European Commission Joint Research Centre Institute for Energy and Transport Ispra, Italy renate.koeble@ext.jrc.ec.europa.eu

2 Background The Renewable Energy Directive (RED) (2009/28/EC) and the Fuel Quality Directive (FQD) (2009/30/EC) fix a threshold of 35 % savings of greenhouse gas (GHG) emissions for biofuels and bioliquids, and set the rules for calculating the greenhouse impact of biofuels, bioliquids and their fossil fuels comparators. To help economic operators calculate GHG emission savings, default and typical values are listed in the annexes of the RED and FQD directives. Both directives forsee the update of the existing values and adding additional pathways in line with technical and scientific progress 6 March

3 Background As requested by the European Commission s Directorate-General for Energy (DG Energy), the JRC has updated the existing input database. The final report (not published yet) describes the assumptions made by the JRC 1 when compiling the updated data set used to calculate default GHG emissions for the different pathways in the directives' annexes. In this context the methodology to calculate soil N 2 O emissions from biofuel cultivation was revised 1 after expert and stakeholder consultations (2011 and 2013) 6 March

4 N 2 O default values in the RED current situation - current values are based on a soil chemistry model (DNDC) and partly IPCC TIER1 (non-european crops) expert knowledge is needed to set-up and run the model no guideline was given in the RED for reporting soil N 2 O emissions Member states NUTS2 reporting (RED Article 19.2) is inhomogeneous: IPCC TIER1 (1997/2006) (18 countries) JEC-WTW v2 N 2 O emissions were scaled to country fertilizer application (4 countries) Stehfest & Bouwman model with reference land use managed grassland + IPCC TIER1 for indirect emissions) (2 countries) 6 March

5 N 2 O default values in the RED general conditions for the update - method should be compatible with other GHG reporting obligations e.g. under UNFCC/Kyoto differences in management factors and environmental conditions should be taken into account (requested in the RED) economic operators / member states need to be able to apply the method (data availability, complexity) 6 March

6 - General Concept - Set of ~ 1000 N 2 O field measurements in agricultural soils (different crops, climates and management) Statistical Model of Stehfest & Bouwman (crop type, soil, climate, N input) Global application (soil, land use, climate maps and N input) 1 Global Nitrous Oxide Calculator (TIER2): Emissions per unit of fertilizer input for different -biofuel crops -N input levels -soil type -climate Global average emission ~0.95% of N input global average IPCC TIER1: 1% of mineral and manure N input are directly released as N 2 O from mineral soils basis for update of default values 1 the global application of the model is based on different data for IPCC and GNOC 6 March

7 - General Concept - The Stehfest & Bouwman statistical model Stehfest and Bouwman (2002, 2006) developed a statistical model to describe on-field emissions N 2 O emissions from soils under agricultural use based on the analysis of 1008 N 2 O emission measurements in agricultural fields where Constant value E = exp c + ev Parameter Parameter class or unit Effect value (ev) Fertilizer Input * N application rate in kg N ha-1 yr-1 Soil organic C content <1 % % >3 % ph < > Soil texture Coarse 0 Medium Fine Climate Subtropical climate Temperate continental climate 0 Temperate oceanic climate Tropical climate Vegetation Cereals 0 Grass Legume None Other March 2015 >1.25 Wetland g cm-3 rice n/a 7 Length of Experiment 1 yr E = N 2 O emission (as kg N 2 O-N ha -1 yr -1 ) c = constant ( ) ev = effect value for different drivers

8 - General Concept - The Stehfest & Bouwman statistical model IPCC emission factor for direct emissions is based on a global mean of S&B Fertilizer Induced Emissions - FIE 0.06 Variation of fertilizer induced emissions from agricultural soils under different environmental conditions and fertilizer input rates applying the Stehfest and Bouwman (2006) model Where: FIE = (E fert E unfert ) / N appl E fert = Emissions from the fertilized plot (kg N 2 O-N) Fertilizer induced emissions (kg N2O-N Emissions / kg Fertilizer N input) E unfert = Emissions from the unfertilized plot (kg N 2 O-N) N appl = mineral fertilizer and manure N application (kg) N input kg ha-1 Agricultural Fields: Minimum case for Cereals in Temperate Oceanic Climate (SOC <1%; ph >7.3; medium soil texture) Agricultural Fields: Mean case for Cereals in Temperate Oceanic Climate (SOC 1-3%; ph ; coarse soil texture) Agricultural Fields: Maximum case for Cereals in Temperate Oceanic Climate (SOC >3%; ph <5.5; fine soil texture) IPCC (2006) factor for direct N2O emissions from fertilizer input 6 March

9 - General Concept - Combining Stehfest & Bouwman (S&B) and IPCC (2006) Direct Emissions N 2 O-N direct_fert = (N min + N man ) * 0.01 replaced by FIE based on S&B (TIER 2) 1 N 2 O-N direct_cr = N cr * 0.01 not replaced by FIE based on S&B model N 2 O-N organic_soils = 8 kg N 2 O-N ha -1 (temperate climate) 16 kg N 2 O-N ha -1 (tropical climate) Indirect Emissions N 2 O-N volatilization = (N min * 0.1) + (N man * 0.2) * 0.01 N 2 O-N leaching/runoff* = (N min + N man + N cr ) * 0.3 * Blue = Emission Factors Green = fractions N min = mineral Fertilizer N Input (kg/ha) N man = N from manure application (kg/ha) = N from crop residues (kg/ha) N cr 1 only for mineral soils, for organic soils IPCC (TIER 1 is applied) *only regions where leaching/runoff occurs 6 March

10 - General Concept - Combining Stehfest & Bouwman (S&B) and IPCC (2006) S&B does not cover organic soils IPCC (2006) method is applied S&B does not cover boreal regions For biofuel crops cultivated in boreal regions, the same factor as for temperate regions is applied (assumption: biofuel crops will be grown in boreal regions only in locations where climate conditions are close to temperate ones) 6 March

11 - General Concept - Differences & amendments to IPCC (2006) Dry matter fraction of harvested product is aligned with the values in the JEC WTW study to be consistent. The latter are assumed to reflect more recent observations. N input from oilpalm and crop residues based on recent literature are calculated to be 159 kg N/ha for oilpalm and 44 kg N/ha for coconut as yearly average during the plantations lifetime N return from vignasse and filtercake to the field is kg N per ton of sugarcane fresh yield. Only ½ of the manure input from the global data set was considered (a. uncertainty in the data, b. if no manure is applied, extra mineral fertilizer would be needed to achieve the same yield)

12 Differences to IPCC (2006) Global Nitrous Oxide Calculator (GNOC) - General Concept - IPCC (2006) underestimates N input from belowground residues root biomass and/or N content (E4tech study and other literature) Correction of Nitrogen fraction in below-ground biomass from to 0.074

13 GNOC and IPCC (2006) Soil N 2 O Emission from different pathways under different fertilizer input and environmental conditions. Crop: Wheat Yield: 7000 kg/ha Climate: Temperate Oceanic Leaching: yes Global Nitrous Oxide Calculator (GNOC) - General Concept - Soil organic carbon: low C <1%, high C >3% ph: Soil texture: medium

14 - Global Calculations - Spatial resolution ~10 by 10km2 most global data sets required for the calculations are available at this resolution Reference year 2000 Detailed land use data set is available, providing crop area and yield for single crops and the required resolution Input data sets with global coverage Ensure as far as possible equal detail for all parts of the world Cover a wide range of potential biofuel feedstock defined by the Commission Biofuel Crop S&B Vegetation class Barley Cereals Rye Cereals Sorghum Cereals Triticale Cereals Wheat Cereals Rapeseed Cereals 2 Maize Other 1 Sugarbeet Other Sugarcane Other Cassava Other Coconut Other Oilpalm Other Safflower Other Sunflower Other Soybean Legumes 1 following the classification of crop types in Stehfest and Bouwman (2006), row crops are summerized in the vegetation class other 2 screening the measurement data we concluded that emissions from rapeseed are more similar to the cereals class than to the crops in the "other" class. This trend was also observed by Walter, K. et al., Direct nitrous oxide emissions from oilseed rape cropping - a metaanalysis. GCB Bioenergy.

15 - Global Calculations - Mineral fertilizer and manure N data based on IFA mineral fertilizer data on a country level disaggregated using FAO statistics on fertilizer use by crop for the different countries for the single crops mineral fertilizer input per ha for a ~10by10km grid was calculated manure data is based on FAO animal feedstock and IPCC default method to derive N input manure was distributed homogeneously within arable land Input Data

16 - Global Calculations - Crop distribution and yield Input Data available globally on a ~10 by 10km grid for >100 single crops for the years ~2000 from Monfreda et al. (2008)* *Monfreda, Ch.; Ramankutty, N. and Jonathan A. Foley, J.A. (2008), "Farming the planet: 2. Geographic distribution of crop areas, yields, physiological types, and net primary production in the year 2000", Global Biogeochemical Cycles, Vol.22, 1-19.

17 - Global Calculations - Input Data Environmental parameters - Soil properties were calculated based on the Harmonized World Soil Database by Hiederer* (2009). - Climate zones as defined in IPCC (2006) are based on Carre** et al. (2010) - Areas where leaching occurs has been calculated according to IPCC (2006) based on soil and climate data (WorldClim) *Hiederer, R. (2009), Joint Research Centre, Institute for Environment and Sustainability, Land management and Natural Hazards Unit, pers. communication. ** Carre, F.; Hiederer, R.; Blujdea, V. and Koeble, R. (2009): Guide for the Calculation of Land Carbon Stocks Drawing on the 2006 IPCC Guidelines for National Greenhouse Gas Inventories

18 - Results - N 2 O emissions in 2000 Rapeseed EU consumption: 87% domestic production, 9% import from Ukraine (source: FAO)

19 Reference Year: 2000 Fertilizer: Mineral Manure Global Nitrous Oxide Calculator (GNOC) - Results -

20 - Results - N 2 O emissions in 2000 Sugarbeet EU consumption: 100% domestic production (source: FAO)

21 - Results - N 2 O emissions in 2000 Oilpalm EU consumption: Palmoil import from Indonesia (42%), Malaysia (40%), Papua Neuguinea (8%) (source: FAO)

22 - Results - Global weighted average from all regions supplying EU market GNOC results for the year 2000 IPCC TIER1 for the year 2000 GNOC results for 2010/ Results calibrated with recent data: Mineral fertilizer for 2010/11 from IFA Crop statistics 2010/11 from FAO

23 - Results - Global weighted average from all regions supplying EU market

24 - Summary - Methodology is consistent with IPCC (2006) on a global scale Methodology allows to take into account local management and environmental conditions Detailed description of the methodology available Calculations for a specific site can be done by spreadsheet calculation OR

25 - Summary - The GNOC online tool 6 March