The agriculture, forestry and other land use sector are responsible for 24% (10–12 Pg CO2e per year) of anthropogenic greenhouse gas (GHG) emissions worldwide, with concomitant opportunities for mitigation. A scientific panel used deliberative methods to identify ten technical measures comprising 26 sub-measures to reduce GHG emissions from agriculture in France. Their abatement potential and cost are compared. The proposed measures concern nitrogen (N) management, management practices that increase carbon stocks in soils and biomass, livestock diets, and energy production and consumption on farms. Results show that the total abatement potential can be divided into three parts. One third of the cumulated abatement potential corresponds to sub-measures that can be implemented at a negative technical cost. These sub-measures focus on increased efficiency in input use including N fertilisers, animal feed and energy. The second third are sub-measures with moderate cost (<€25 per metric Mg of avoided CO2e). These sub-measures require specific investments or changes to cropping systems, but additional costs or lower incomes are partially compensated for by a reduction in other costs or by the production of other marketable products. The remaining third are high-cost sub-measures (>€25 per metric Mg of avoided CO2e). These require investment with no direct financial return, the purchase of particular inputs, dedicated labour time or involve production losses. Assuming additivity, the cumulated abatement is 32.3 Tg CO2e per year in 2030, but only 10 Tg (i.e. 10% of current agricultural emissions) when calculated under current inventory rules. This study confirms that a significant abatement potential exists in the agricultural sector, with two thirds of this potential at low or even negative cost. This is likely to be an underestimated as it is based on a status quo of the current agricultural system. Results also emphasise the need to upgrade inventory rules so that efforts to reduce emissions can be accounted for

Meeting future policy targets for bioenergy development worldwide poses major challenges for biomass feedstock supply chains in terms of competitiveness, reliability and sustainability.This paper reviews current knowledge on the sustainability of agricultural feedstock supply chains and emphasizes future research needs. It covers annual and perennial feedstocks, and environmental, economic and social aspects. Knowledge gaps and technological options to assess and meet sustainability criteria are reviewed from plot to landscape and global scales.Bioenergy feedstocks present a wide range of dry matter yields, agricultural input requirements and environmental impacts, depending on crop type, management practices, and soil and climate conditions. Their integration into farmers׳ cropping systems poses specific challenges in terms of environmental impacts, but also opportunities for improvements via the use of grass–legume intercropping or residues from biomass conversion processes. Taking into account the spatial distribution of bioenergy crops is paramount to assessing their environmental impacts, in particular, on biodiversity or the food versus energy competition issue. However, few modeling frameworks convey the full complexity of the underlying processes and drivers, whether economic, social or biophysical. In particular, social impacts of bioenergy projects are seldom assessed and there is no methodological consensus.The main research areas identified involve multi-crop and multi-site experiments, along with modeling, to optimize management practices and cropping systems producing bioenergy, possibly on alternative lands and under future climate changes; the design of innovative cropping systems using expert knowledge to ensure suitable integration into farmers׳ cropping systems; the collection of detailed data on the location of bioenergy crops to validate theoretical modeling frameworks and improve sustainability assessment; tackling direct and indirect effects of bioenergy development on land-use changes via coupled economic and agronomical models; investigating the effect of perennial stands on biodiversity in relation to previous land-use and landscape structure; and further developing currently-available methodologies to fully appraise the social implications of bioenergy projects

No abstract

No abstract

The purpose of this study was (i) to select options for enteric methane abatement in French conditions, while maintaining production and changing practices but not systems, and (ii) to evaluate the extent of abatement and its cost from 2010 to 2030. Two options were selected: supplying unsaturated fats, and using nitrates as a dietary additive in the diet. Unsaturated fats resulted in a higher abatement, because a greater number of animals were concerned by the option, but incurred a higher total cost and a higher cost per ton of CO2-equivalent avoided. The results were sensitive to methodology, and to variations in the choice of fats and in the cost of ingredients, among other factors. Given their cost, evaluated in the frame of a marginal abatement cost curve, these options will require strong public policies for their applicatio

Ouvrage issu du rapport de l'étude « 4 pour 1 000 France » Le présent ouvrage est une synthèse du rapport de l'étude scientifique conduite par la Direction de l'expertise scientifique collective, à la prospective et aux études d'INRAE. Cette étude a été sollicitée conjointement par l'Agence de l'environnement et de la maîtrise de l'énergie (Ademe) et le ministère de l'Agriculture et de l'Alimentation (MAA), convention n° 1660C0020. Le Centre d'accès sécurisé aux données (CASD) a permis l'accès au Réseau d'information comptable agricole (RICA) 1 .Le contenu du rapport et du document de synthèse publiés lors de la présentation des principaux résultats de l'étude en juin 2019, ainsi que du présent ouvrage, n'engage que la responsabilité de leurs auteurs. Le rapport d'étude, source du document de synthèse et de cet ouvrage, a été élaboré par les experts scientifiques sans condition d'approbation préalable par les commanditaires ou l'Inra.Ces documents sont disponibles sur le site institutionnel d'INRAE (www.inrae.fr).

No abstract

Soil organic carbon sequestration measures entail costs to farmers with different individual characteristics and located in different areas. A cost‐effective analysis taking into account these heterogeneities is crucial for developing effective public policy aimed at increasing carbon sequestration. We undertake such an analysis focusing on three soil organic carbon sequestration measures: no‐till, extension of temporary grasslands, and hedgerows. Through an optimization model applied to France, our results show that only extension of temporary grasslands can store carbon at low cost, though their potential for carbon sequestration is also low. For an ambitious carbon sequestration target, no‐till and hedgerows are needed. Because of heterogeneities among farmers, we show that economic incentives are more cost effective than command and control measures. Furthermore, we highlight that the carbon sequestration policy tested here is unable to totally neutralize agricultural greenhouse gas emissions and that a combination of agricultural and environmental policies is essential for tackling climate change.