GREENHOUSE GASES EMISSIONS FROM AGRICULTURE IN FRANCE ( ):

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1 GREENHOUSE GASES EMISSIONS FROM AGRICULTURE IN FRANCE ( ): CONSEQUENCE OF SPECIALISATION AND INTENSIFICATION Josette Garnier, Julia Le Noë, Audrey Marescaux, Alberto Sanz-Cobena, Vincent Thieu, Marie Silvestre, Gilles Billen

2 Trends and major characteristics of N 2 O, CH 4 and CO 2 Changes in GHGs from ice core and modern data N 2 O Time life in the atm : 120 yrs GWP = 265 x that of CO 2 Agricultural source(> 80%) CH 4 Time life in the atm : < 10 yrs GWP = 28 x that of CO 2 for 100 yrs ( NB x 62 for 20 yrs) Agricultural source ( 20 % à 40 %, livestock and/or rice fields) CO 2 Time life in the atm : not applicable GWP = 1 Agricultural source (fertilizer production, gas oil, ) IPCC, 2007

3 Objectives Quantifying current GHG agricultural emissions in all French territories Identification of controlling factors for a determination of the emissions (litterature analysis and own data) Estimating GHG emissions on the long term Past and current Agricultural statistics (cf. J. Le Noë et al., 2018, AEE) Exploring two scenarios (cf. Billen et al., 2018, STOTEN) Continuing trends of opening to distant markets and specialisation into either chemical cropping or intensive livestock farming (O/S) Shifting to autonomy through organic farming, crop and livestock reconnection and demitarian diet (A/R/D) 3

4 Specialisation of the French territories Intensification of cereal production from the 1950, in the North of France Intensification of animal production, in Brittany A disconnection already in place in the 1970 s, and even before! Based on Le Noë et al., 2018, AEE Based on Billen et al., 2018, STOTEN

5 Specialisation of the French territories An increase in perm. grassland in the 1970s, a decrease in the 2010s A progressive increase in forest, especially in the East and South of France NB: No change in the forest for the scenarios

6 Reconstruction of controling factors of N 2 O: 3 contrasted territories as ex. Temperature ha ha ha ha Rainfall Total exogenous fertilisation

7 Reconstruction of controling factors: ex. in contrasted territories Temperature ha ha ha ha Scn: +1.5 C Rainfall Scn: same rainfall Total exogenous fertilisation O/S : reasonned fertil. A/R/D : no min. fertil 2040

8 Reconstructing GHG emissions for the past Determination of N 2 O emissions (from litterature (e.g. Cayuela et al., 2017) and own data, Garnier et al., 2009; Vilain et al., 2012; Benoit et al., 2015) 394 Number of values Inputs Rainfall, kgn ha -1 yr -1 mm yr -1 Temp, C N 2 O emission kgn-n 2 O ha -1 yr -1 Cropland Grassland Forest N 2 O emission related to N input, mean pluviometry and temperature Obs N 2 O emission, kgn/ha/yr N input, kgn/ha/yr 1200 mm/y 20 C 8 C 600 mm/y 20 C 8 C 200 mm/y 12 C

9 Reconstructing GHG emissions for the past Determination of CH 4 emission factors for present (Vermorel et al., 2008; and others in Garnier et al., 2013) Excretion changes in function of structural changes in livestock farming Applying current CH 4 emissions by category of livestock taking into account this structural changes Reconstruction in Le Noë et al., 2018, AEE 9

10 Reconstructing GHG emissions for the past Determination of CO 2 emissions Fertilizers 1 ton of N fertiliser produced emits 0.52 tc-co 2 1 ton of other fertilisers produced emits 1.62 tc-co 2 Feed import 1 ton of imported feed emits 2.68 tc-co 2 Fuel 1 liter of fuel consummed produces 0.71 kg C-CO liter of diesel per ha of cultivated area Percentage of mechanisation, based on the decease of equine 10 10

11 Long term emissions of N 2 O Increasing N 2 O emission linked to intensive fertilisation on cropland, since the 1970 s Lower contribution of grassland and forest Striking increase in all territories of the country 11

12 Long term emissions of N 2 O Worsening N 2 O emissions under O/S scenario Improvement of N 2 O emissions under A/R/D scenario (back to the 1955 s) 11

13 Long term emissions of CH 4 Enteric fermentation represents a large proportion of the total CH 4 Different trajectories in the territories, according to their specialisation into crop or livestock farming Seine Basin : livestock relegated at the periphery of the basin Great West : intensive livestock production, but stabilisation of ruminants Great South West : slight intensification of livestock Strinking increase in the territories arround the Seine Basin (feeding Paris!) 12

14 Long term emissions of CH 4 The Parisian Basin emptied from any livestock at the expense of the surrounding territories for O/S A reconnection under A/R/D, wich overall reduce the emission; extensive livestock spread over the country 12

15 Long term emissions of CO 2 Low CO 2 agricultural emission before a strong mechanisation (post WWII) Increase CO 2 emissions with the increasing use of fertiliser and agricultural machinery Dominant in the Seine Basin and Great South West Additionnal CO 2 linked to feed import in Great West An early specificity of the Parisian basin (1906), a late «industrialisation» in the South of France 13

16 Long term emissions of CO 2 No decrease in the Parisian Basin for O/S (cf. cropping), increase in the South of France (livestock and feed) An overall decrease under A/R/D (no mineral fertiliser use) 13

17 Long term total emissions of GHG kt CO 2 Equ. yr -1 ~ ktons CO 2 yr -1 CH 4 > N 2 O > CO 2 CO 2 underestimated Further specialisation damageable for the environment Structural change is required to decrease GHG emissions NB: Great West, a territory with the highest emissions, cumulating favorable conditions for emissions (rainy, high exogenous inputs, import of feed ) 14

18 Conclusions An approach for a differenciation of GHG emission among the french territories A transition towards industrial agriculture and a specialisation in the territories increased GHG emissions An increased specialisation would still increase GHG emissions contrarily to the commitments of the Paris Agreements (COP 21). Structural changes in agriculture are urgently necessary for a return to acceptable level of GHG emissions NB: Non agricultural emissions must also be reduced (transportation, heating cf. Marescaux et al., 2018) 15

19 Thank you! GREENHOUSE GASES EMISSIONS FROM AGRICULTURE IN FRANCE ( ): CONSEQUENCE OF SPECIALISATION AND INTENSIFICATION Josette Garnier, Julia Le Noë, Audrey Marescaux, Alberto Sanz-Cobena, Vincent Thieu, Marie Silvestre, Gilles Billen

20 References Benoit M., Garnier J., Billen G., Tournebize J., Gréhan E., Mary B. (2015). Nitrous oxide emissions and nitrate leaching in an organic and a conventional cropping system (Seine basin, France). Agric. Ecosyst. Environ. 213: doi: /j.agee Billen G., Le Noë J., Garnier J. (2018). Two contrasted future scenarios for the French agro-food system. Science of the Total Environment : doi.org/ /j.scitotenv Cayuela M.L., Aguilera E., Sanz-Cobena A., Adams D.C., Abalos D., Barton L., Ryals R., Silver W.L., Alfaro M.A.,Pappa V.A., Smith P., Garnier J., Billen G., Bouwman L., Bondeau A., Lassaletta L. (2017). Direct nitrous oxide emissions in Mediterranean climate cropping systems: emission factors based on a meta-analysis of available. AEE. Garnier J., Billen G., Vilain G., Martinez A., Mounier E., Silvestre M., Toche F. (2009). Nitrous oxide (N2O) in the Seine river and basin: observations and budgets. Agric. Ecosyst. Environ. 133 : doi: /j.agee Garnier J., Vilain G., Jehanno S., Silvestre M., Billen G., Poirier D., Martinez A., Decuq C., Cellier P., Abril G. (2013). Methane emissions from land use, livestock farming, and the river network of the Seine basin (France), Biogeochemistry, 116: DOI /s IPCC, 2007, Climate change 2007, Synthetic report Groups I, II, II. AR4. Core writting team, Pachauri RK & Reisinger A (Eds) IPCC, Geneva, Switzerland, 104 pp Le Noë J., Billen G., Esculier F., Garnier J. (2018). Long term socio-ecological trajectories of agro-food systems revealed by N and P flows: the case of French regions from 1852 to Agriculture, Ecosystems and Environment 265: doi.org/ /j.agee Marescaux A. Thieu V., Garnier J. (2018). Carbon dioxide, methane and nitrous oxide emissions from the humanimpacted Seine watershed in France. Science of the Total Environment. 643: doi.org/ /j.scitotenv Vermorel M, Jouany J, Eugène M, Sauvant D, Noblet J, Dourmad J (2008) Evaluation quantitative des émissions de méthane entérique par les animaux d élevage en 2007 en France. INRA Prod Anim 21: Vilain G., Garnier J., Tallec G., Tournebize J. (2012). Temporal and spatial indirect N2O emissions from shallow groundwater in an agricultural catchment (France). Biogeochemistry, 111: DOI /s