OCL 2020, 27, 69 © F. Flénet et al., Hosted by EDP Sciences, 2020 https://doi.org/10.1051/ocl/2020068 OCL Oilseeds & fats Crops and Lipids Available online at: www.ocl-journal.org RESEARCH ARTICLE Examination of an attempt to improve rapeseed cultivation in France in order to reduce the greenhouse gas emissions of biodiesel☆ Francis Flénet*, Dominique Wagner and Pascal Simonin Terres Inovia, Avenue Lucien Brétignières, 78850 Thiverval-Grignon, France Received 1 February 2020 – Accepted 13 November 2020 ® Abstract – “Démarche de progrès DIESTER ” was an attempt by French farmers, industrialists, technicians, agricultural cooperatives and private grain trading companies to continuously improve the environmental performance of rapeseed biodiesel. The objective was to implement certain rapeseed cultivation operations that had shown their efficiency in previous studies to reduce greenhouse gas (GHG) emissions: (i) the use of decision support systems (DSS) to calculate nitrogen fertilisation rates, (ii) the cultivation of legumes as intercrops with rapeseed or (iii) as previous crops. This paper first presents an estimate of the potential GHG effects of these cultivation operations, using results from previous studies obtained under experimental conditions or using crop modelling. It then presents the level of adoption by farmers of these cultivation operations in the context of the “Démarche de progrès DIESTER®” initiative to continuously improve the environmental performance of rapeseed biodiesel. Depending on the year, 39 to 74 agricultural cooperatives and grain trading companies were involved in the study, and 90 170 to 283 480 hectares of rapeseed have been monitored. This is the first time in France that an attempt to improve cultivation operations for environmental reasons has been made on such a scale. The average GHG reduction values, compared to fossil fuels, varied from 49.5 to 55.8% depending on the year, which was most often above the 50% minimum reduction value for sustainable biodiesel, but well below the 70% minimum for very low GHG emission biodiesel. Using the results of previous studies, this article shows that the widespread use of decision support systems to calculate mineral N fertilizer rates, and the cultivation of legumes as a preceding crop or intercrop, would make it possible to significantly reduce GHGs and make it possible to produce very low GHG-emitting biodiesel in certain locations and/or years. However, the actual changes in cultural operations were too small to be effective. The reasons for this lack of impact and how to achieve results in the future are discussed in this article. Keywords: greenhouse gas / oilseed rape / cultivation operations / continuous improvement Résumé – Étude d’une tentative d’amélioration des pratiques culturales du colza en France, dans le ® but de réduire les émissions de gaz à effet de serre du biodiesel. La « démarche de progrès DIESTER » était une tentative d’amélioration en continu des bilans environnementaux du biodiesel de colza qui a mobilisé les agriculteurs français, les industriels, les organismes agricoles de conseil et de R&D, ainsi que les organismes stockeurs. L’objectif était de mettre en œuvre certaines pratiques culturales qui avaient montré dans de précédentes études leur efficacité pour réduire les émissions de gaz à effet de serre (GES) : (i) l’utilisation d’un outil d’aide à la décision pour calculer la dose d’engrais azoté, (ii) la culture de légumineuses en association avec le colza ou (iii) en précédent cultural. Cet article présente tout d’abord une estimation des effets potentiels sur les GES de ces pratiques culturales, en utilisant les résultats de précédentes études obtenus en expérimentation ou par modélisation. Il présente ensuite le niveau d’adoption de ces pratiques par les agriculteurs dans le cadre de la démarche de progrès DIESTER®. Suivant les années, de 39 à 74 organismes stockeurs ont participé à la démarche et 90 170 à 283 480 ha de colza ont été suivis. C’est la première fois qu’une démarche de progrès pour améliorer les bilans environnementaux a été ☆ Contribution to the Topical Issue “Biodiesel / Biodiesel”. *Correspondence: f.fl[email protected] This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. F. Flénet et al.: OCL 2020, 27, 69 entreprise à une telle échelle en France. Suivant les années, le gain de GES permis par le biodiesel a été de 49,5 à 55,8 % par rapport aux émissions du gazole fossile. L’objectif de 50 % pour que le biodiesel soit considéré comme durable a ainsi été atteint la plupart du temps, mais le gain a toujours été bien inférieur à la valeur de 70 % demandée pour le biodiesel à très bas niveau de GES. En utilisant les résultats de précédentes études, cet article montre que la généralisation de l’utilisation d’un outil d’aide à la décision pour calculer la dose d’engrais azoté minéral et la culture de légumineuses, comme précédent cultural ou en association avec le colza, permettraient de réduire significativement les GES et rendraient possible la production de biodiesel à très bas niveau de GES dans certains territoires ou dans certaines années. Mais, l’évolution des pratiques culturales réellement observée a été trop limitée pour avoir un effet significatif sur les GES. La raison de ce manque de résultats et la manière dont il faudrait s’y prendre pour réussir sont discutés dans cet article. Mots clés : gaz à effet de serre / colza / pratiques culturales / démarche de progrès variability of GHG emissions was high, ranging from 30–32 to 1 Introduction À1 42–44 g CO2 equivalent MJ for emissions including The European Directive on the promotion of the use of transportation and biodiesel processing (Flénet, 2012). This energy from renewable sources (Directive 2009/28/EC) aims variability is mainly due to differences in nitrogen applications both at reducing greenhouse gas (GHG) emissions, in order to and seed yields. Compared to fossil fuel emissions À1 contribute to compliance with the Kyoto Protocol to the United (83.8 g CO2 eq. MJ ), in 2010, almost all values were 50% Nations Framework Convention on Climate Change, and at lower or less. However, Flénet (2012) showed that this 50% reducing the transport sector’s dependence on oil imports. This GHG reduction criterion could not be met by half of the European directive also stipulates that the production of cooperatives or grain trading companies in years of poor seed biofuels must meet sustainability criteria. One of these criteria yield performance. The potential to reduce GHGs by is a reduction of GHG emissions from the use of biofuels and improving the efficiency of mineral N fertilization was bioliquids by at least 50% from 1 January 2017 (60% from demonstrated, while the application of organic matter appeared 1 January 2018 for biofuels and bioliquids produced in to be largely ineffective due to increased soil N2O emissions. installations where production started on or after 1 January Thus, from 2013/2014 to 2016/2017, the biodiesel producer 2017). GHG emissions are calculated by adding emissions SAIPOL decided to promote improved cultivation operations from the extraction or cultivation of raw materials, carbon by farmers, to reduce GHG emissions from rapeseed, by stock changes due to land-use change, processing, transport providing financial support to cooperatives and grain trading and distribution, fuel used and emission savings (carbon companies that would engage in actions to improve nitrogen accumulation in soils through improved agricultural manage- use efficiency or seed yield. This article focuses on the three ment, carbon capture and geological storage, etc.). The actions to improve nitrogen use efficiency that have been Directive provided a default value for GHG emissions from proposed to cooperatives or grain trading companies. These À1 rapeseed raw material of 29 g CO2 equivalent MJ . GHG actions have proven to be effective in previous studies. The emissions from the cultivation of agricultural raw materials first action was the use of Decision Support Systems (DSS) to were also calculated in areas classified at level 2 of the calculate nitrogen fertilization rates. In a previous study, using nomenclature of territorial units (NUTS2), which is the a survey on the use of DSS in France and crop modelling, regional level in France. In this country, all rapeseed NUTS2 Ben Aoun (2015) showed that in 2011/12 in France, the values were less than or equal to 29 g of CO equivalent MJÀ1, generalization of DSS and their good use would have led to 2 À except in Provence-Alpes-Côte d’Azur. With such values, the both a 27 kg N ha 1 decrease in mineral nitrogen fertilization 50% GHG reduction is achieved if the carbon stock changes and an only slight decrease in yield. These results were caused by indirect land-use change are not taken into account, validated by experimental data. The second and third actions but there are demands to account for indirect land-use changes were the cultivation of leguminous crops, intercropped with due to biofuel production. In addition, in recent years, several rapeseed or as a previous crop. Experimental data obtained for countries such as Germany or Sweden have set a mandatory different years and locations showed that it would decrease the target for biofuel use expressed as the amount of CO saved, optimal N fertilization rate by 30 (Cadoux et al., 2015) and 40 2 À instead of the amount of biofuel, which has led to an increase in to 50 (Dumans et al., 2010)kgNha 1 respectively. Christen the price of very low GHG-emitting biofuels (70% savings and and Sieling (1995) reported an increase in the yield of rapeseed more).