Changes in soil carbon and nitrogen following tillage conversion in a long-term experiment in Northern France

International audienceAlthough continuous no-till (NT) is recommended for erosion control and carbon sequestration, it often has a limited duration since farmers alternate between NT and full inversion tillage (FIT) to control weed infestation and avoid soil compaction. In this paper, we evaluate the effect of continuous tillage and tillage conversion of NT to FIT and vice versa on SOC and SON stocks, in a long-term experiment at Boigneville in Northern France. Continuous NT (CNT) and FIT (CFIT) treatments were established in 1991 and maintained until 2011 while half of the plots were converted in 2005: from CNT to new FIT (NFIT) and CFIT to new NT (NNT). Bulk densities and organic C and N contents were determined in 2001 and 2011 down to the old ploughing depth (opd) which was also measured. SOC and SON stocks were calculated at equivalent soil mass by correcting either bulk densities or the opd. Both methods produced very close results and similar conclusions. A typical gradient of SOC and SON concentrations vs depth was observed in CNT as opposed to a rather uniform distribution in CFIT. CNT resulted in SOC concentration in the top soil (0-5 cm) higher by 38% in 2001 and 53% in 2011 compared to CFIT. Conversely, it led to a SOC reduction in the deeper layer (ca. 10-28 cm) by 14% in 2001 and 18% in 2011. The global effect was no significant change in SOC and SON stocks between treatments over the old ploughed layer (4060 t soil ha(-1)) in both years: 43.2 and 45.0 t C ha(-1) in 2001 and 44.7 and 45.8 t C ha(-1) in 2011, in CNT and CFIT, respectively. In 2011, six years after tillage conversion, the stratification of SOC and SON had disappeared in NFIT whereas a new one had appeared in NNT with a smaller gradient than in CNT. SOC or SON stocks over the old ploughed layer did not differ significantly between treatments after 6 years of conversion: SOC stocks were 45.8, 43.2, 44.7 and 43.1 t C ha(-1) in the CFIT, NFIT, CNT and NNT treatments, respectively. Furthermore, SOC stocks below the old ploughed layer (ca. 28-40 cm) were slightly greater in FIT than in NT treatment (10.9 vs 8.7 t C ha(-1)). In this experiment, continuous or conversion tillage did not result in any C sequestration benefit. (c) 2013 Elsevier B.V. All rights reserved

InnovAB - Améliorer les systèmes de grande culture en agriculture biologique : enseignements d’un réseau d’expérimentations de longue durée

Pour accompagner l’essor actuel de l’agriculture biologique, il est important de disposer de référencessur la conception de systèmes de culture durables, pour des agriculteurs récemment convertis ou plusexpérimentés. L’évaluation faite de systèmes de grande culture bio innovants, testés en réseaud’expérimentations système de longue durée, montre de bonnes contributions au développementdurable, avec des performances économiques et environnementales satisfaisantes. Des points devigilance ressortent sur le maintien à long terme du potentiel de production des parcelles (risques dedéveloppement non contrôlé d’adventices, de carences en éléments minéraux). Les systèmesprivilégiant la mobilisation de leviers agro-écologiques montrent des perspectives intéressantes

Elfe. Une base de données pour caractériser les émissions gazeuses

In France, 70% of ammonia and 18% of greenhouse gas (GHG) originate from the livestock sector. Thus, improving knowledge on the magnitude and origin of gaseous emissions is essential to reduce them, and then meet societal requirements and setup regulations at national and European levels. A consortium involving research (Inra, Irstea) and technical development (Ifip, Itavi, Idele, CRAB, Terres Innovia, Arvalis) was created to implement a robust database (ELFE) gathering (inter)national literature references on gaseous emissions of poultry, pork, herbivore productions and related indicators. With the help of the database ELFE, we aim to determine emission factors (EF) for NH3, GHG, particles and odors in various technical itineraries integrating the different steps of animal and manure management (i.e. building, manure storage and treatment, spreading and pasture). Building the structure of the database was the first step of this project financed by the French Agency of the Environment and the Control of Energy (ADEME). Further on, national and international literature data were integrated into the database. At the moment, around 1,000 publications are recorded, essentially focusing on NH3 and GHG emissions. The next steps concentrate on data analysis to determine average EF’s per itinerary and EF-variability due to metadata (i.e. animal type, climate, diet, duration, storage type...). Outcomes will be published in scientific journals but also made available for stakeholders as guidance documents (i.e. fact sheets, technical reports). The purpose of these documents is to advise agricultural consultants and authorities on ways of reducing emissions and improving air quality in livestock production systems

Une base de données pour caractériser les émissions gazeuses

Improving the knowledge on the magnitude and origin of gaseous emissions from livestock sector is essential toreduce emissions, to meet the societal requirement and to setup regulations at national and European levels. Aconsortium involving research (Inra, Irstea) and technical development (Ifip, Itavi, Idele, CRAB, Terres Innovia,Arvalis) was created to setup a robust database (ELFE) on (inter)national literature references on gaseousemissions of poultry, herbivore, pork productions and related indicators. With help of the database ELFE, weaim to determine emission factors (EF) for NH3, GHG, odors and particles per technical itinerary, in order tointegrate different steps of animal and manure management (i.e. building, manure storage and treatment,spreading and pastures) in the estimations of livestock emissions. Building the structure of the database was thefirst step of this project. Further on, national and international literature data has been integrated in the database.The next steps concentrate on data analysis to determine average EF’s per itinerary and EF-variability due tometadata (i.e. animal type, climate, diet, duration, storage type...). Outcomes will be published in scientificjournals but also made available for stakeholders as guidance document (i.e. fact sheets, technical reports).L’amélioration des connaissances relatives aux émissions d’ammoniac et de GES du secteur de l’élevage estindispensable afin de réduire son impact environnemental et ainsi répondre aux exigences sociétales etréglementaires au niveau national et Européen. Un consortium regroupant des acteurs de la recherche (Inra,Irstea) et du développement (Ifip, Itavi, Idele, CRAB, Terres Inovia, Arvalis) s’est créé pour mutualiser lesréférences relatives aux émissions gazeuses des élevages de volailles, d’herbivores et de porcs dans une base de données intitulée ELFE (ELevages et Facteurs d’Emission). Son objectif principal est de produire des facteursd’émissions (FE) NH3, GES, odeurs et particules par itinéraire technique en intégrant les différents postesd’émissions (bâtiment, stockage, traitement, épandage et pâturage). La première étape du projet a été d’établir lastructure de la base pour intégrer les données d’émissions publiées et les métadonnées associées pouvantexpliquer leur variabilité. La seconde étape est l’alimentation de cette base à partir des références disponiblesdans la littérature internationale. L’étape suivante concerne leurs analyses en vue de calculer des FE moyens paritinéraire technique, mais aussi d’étudier l’influence des métadonnées sur leurs variabilités. La diffusion desrésultats sera réalisée sous forme de publications scientifiques mais aussi sous forme d’un guide qui seralargement diffusé auprès des acteurs des filières animales

Elfe. Une base de données pour caractériser les émissions gazeuses

Elfe. Une base de données pour caractériser les émissions gazeuses. International Symposium on Emissions of Gas and Dust from Livestock (EmiLi