For decades, conservation tillage has been promoted as a measure to increase carbon stocks in arable soils. Since organic farming improves soil quality and soil carbon storage, reduced tillage under ...organic farming conditions may further enhance this potential. Therefore, we assessed soil organic carbon (SOC) stocks of reduced tillage compared with mouldboard ploughing in nine organic farming field trials in France, Germany, the Netherlands, and Switzerland with the same sampling and analytical protocol. We sampled soil cores until a depth of 100 cm to determine soil carbon stocks that are relevant for climate change mitigation but are often overlooked in tillage studies with shallow sampling depths. The studied field experiments were between 8 and 21 years old and comprised different soil types with clay contents ranging from 10% to 50%. SOC stocks increased with increasing clay-to-silt ratio, precipitation and organic fertiliser input. Across sites, reduced tillage in comparison with ploughing increased SOC stocks in the surface layer (0–10/15 cm) by 20.8% or 3.8 Mg ha−1, depleted SOC stocks in the intermediate soil layers to 50 cm soil depth with a maximum depletion of 6.6% or 1.6 Mg ha−1 in 15/20–30 cm and increased SOC stocks in the deepest (70–100 cm) soil layer by 14.4% or 2.5 Mg ha−1. The subsoil SOC stock increase may be linked to the inherent soil heterogeneity. Cumulative SOC stocks increased by 1.7% or 1.5 Mg ha−1 (0–50 cm, n = 9) and 3.6% or 4.0 Mg ha−1 (0–100 cm, n = 7) by reduced tillage compared with ploughing with estimated mean C sequestration rates of 0.09 and 0.27 Mg ha−1 yr−1, respectively. There was no effect of field trial duration on tillage induced cumulative SOC stocks differences. Under reduced tillage, biomass production was 8% lower resulting in a decrease of crop C input by 6%. However, this reduction may have been outbalanced by increased C inputs from weed biomass resulting from a higher weed incidence in reduced tillage, which warrants further research. Thus, reduced tillage in organic farming has the potential to increase total SOC stocks, while crop management has to be improved to increase productivity.
•Reduced tillage in organic farming has the potential for carbon sequestration.•Reduced tillage in organic farming stratifies SOC stocks similarly to no-till.•SOC stocks in subsoils affect the climate change mitigation evaluation of tillage systems.
Functional attributes of weed communities differ in reduced and conventional tillage.Certain weed attributes to reduce crop competition exist under reduced and conventional tillage systems.Crop ...type is more relevant than tillage in determining shifts in functional composition.
The adoption of non-inversion tillage practices has been widely promoted due to their potential benefits in reducing energy consumption and greenhouse emissions as well as improving soil fertility. However, the lack of soil inversion usually increases weed infestations and changes the composition of the weed community. Weed management is still a main drawback for the wider adoption of reduced tillage practices. However, it is not entirely clear whether these changes in weed communities are a consequence of non-random filters on the functional attributes of weed species and may thus affect the potential weed-crop competition relationship.
Here, we analyse the changes in weed diversity, community composition, and the functional attributes of weed communities under reduced (non-inversion) and conventional (inversion) tillage. We discuss their potential effects on the competitiveness against crop production using data from two crops of seven on-going organic and low-input field trials in different climatic regions across Europe. Weeds were evaluated after post-emergence weed control methods. We used the community weighted mean values of the life form (annuals versus perennials), specific leaf area, seed weight, canopy height, seed bank longevity, soil nutrient conditions affinity, beginning of flowering and flowering span. Moreover, the effect of the crop type on the functional attributes was also evaluated.
Overall, the tillage system affected the composition and functional attributes of the weed communities. Weed community changes may imply a reduction in weed-crop competition under both tillage systems. For instance, weed communities under reduced tillage were potentially less competitive because they were shorter and had less affinity to nutrients. On the other hand, weed communities under conventional tillage had potentially less seed production and a lower abundance of perennial species. Our study thus supports tillage as an important driver of the functional attributes of weed communities, but both tillage systems can have their downside. However, the crop type was overall more relevant than the tillage in determining most of the trait values of the weed communities.
Tillage modifies soil structure and crop residue distribution and in turn affects the ability of soil micro-organisms to degrade soil organic matter and release nutrients for crop growth. In organic ...farming, soil microbiological activity is of primary importance as nutrient supply is mainly dependent on the degradation of soil organic matter by soil micro-organisms. The aim of this work was therefore to study, in organic farming, the effects of four tillage systems mouldboard ploughing (MP), shallow mouldboard ploughing (SMP), reduced tillage (RT) and shallow soil tillage (ST) on soil structure, soil microbial biomass (SMB) and its potential activity (Cmin) during the first year following the treatments. To study simultaneously the effects of soil structure modifications and crop residue distribution on SMB and Cmin, we adopted a sampling scheme based on a morphological description of soil profiles. We distinguished and sampled compacted and non-compacted clods (Δ and Γ clods) at three depths (0-5, 5-15 and 15-30 cm). This method enabled us to have a precise estimation of the effects of tillage treatments on SMB and Cmin. MP reduced compacted zones and limited unfavourable conditions for microbial growth and enabled a homogenous distribution of SMB in the soil profile. At the opposite, the ST increased compacted zones in the soil profile and limited SMB development below the top few centimetres. The SMP and the RT systems appeared as intermediate techniques. RT seemed to be a conservation tillage technique which could be used in organic farming.
In November 2018, ITAB (Institute of Agriculture and Organic Food) and INRA (National Institute for Agronomic Research) organized a transdisciplinary seminar to bring together stakeholders to: i) ...share issues associated with soil management in Organic Farming (OF) systems, ii) collectively define the main research questions to be addressed; and iii) facilitate the construction of networks or projects. More than 150 participants attended the seminar, which was designed using the method of citizen facilitation of the community forum type (Town Hall Meeting) allowing all parties to express themselves and a live summary by experts. The seminar identified important knowledge gaps on soils in OF systems and research needs. The 20 questions resulting from these exchanges relate to: i) the overall functioning of soils, more particularly the major biogeochemical cycles Carbon, Nitrogen, Phosphorus (CNP) and biological interactions; ii) the long-term effects of agricultural practices more or less specific to OF systems; (iii) soil protection; and iv) soil diagnostic and management tools. Most of the issues identified are generic and require multidisciplinary research, especially when responding to systemic issues. The seminar identified needs in terms of device and research observatory that provide the references necessary to validate or adapt to OF systems the tools and methods of evaluation and soil management available for conventional systems. The main questions identified during the seminar are discussed and confronted with recent dynamics in terms of soil research and development.
En noviembre de 2018, el ITAB (Instituto de Agricultura y Alimentos Orgánicos) y el INRA (Instituto Nacional de Investigaciones Agronómicas) organizaron un seminario transdisciplinario para reunir a las partes interesadas para: i) compartir problemas asociados con el manejo del suelo en Agricultura Orgánica (AO) sistemas, ii) definir colectivamente las principales preguntas de investigación que se abordarán; y iii) facilitar la construcción de redes o proyectos. Más de 150 participantes asistieron al seminario, que fue diseñado utilizando el método de facilitación ciudadana del tipo foro comunitario (Town Hall Meeting) que permite que todas las partes se expresen y un resumen en vivo por parte de expertos. Los resultados confirmaron las importantes lagunas de conocimiento sobre los suelos en los sistemas de AO y las necesidades de investigación. Las 20 preguntas resultantes de estos intercambios se relacionan con: i) el funcionamiento general de los suelos, más particularmente los principales ciclos biogeoquímicos Carbono, Nitrógeno, Fósforo (CNP) e interacciones biológicas; ii) los efectos a largo plazo de las prácticas agrícolas más o menos específicas de los sistemas de AO; iii) protección del suelo; y iv) herramientas de diagnóstico y manejo de suelos. La mayoría de los problemas identificados son genéricos y requieren una investigación multidisciplinaria, especialmente cuando se trata de responder a problemas sistémicos. El seminario identificó necesidades en cuanto a dispositivo y observatorio de investigación para obtener las referencias necesarias para validar o adaptar, en sistemas de AO, las herramientas y métodos de evaluación y manejo de suelos disponibles para sistemas convencionales. Las principales cuestiones dentificadas durante el seminario son discutidas y confrontadas con la dinámica reciente en términos de investigación y desarrollo de suelos.
En novembre 2018, l'ITAB (Institut de l’agriculture et de l’alimentation biologiques) et l’INRA (Institut national de la recherche agronomique) ont organisé un séminaire transdisciplinaire pour : i) partager les enjeux associés à la gestion des sols dans les systèmes en Agriculture Biologique (AB), ii) définir collectivement les principales questions de recherche à traiter ; et iii) faciliter la construction de réseaux ou de projets. Plus de 150 participants ont assisté au séminaire qui a été conçu à partir de la méthode d’animation citoyenne de type forum communautaire (Town Hall Meeting), permettant à l’ensemble des parties de s’exprimer et à une synthèse en direct par des experts d’être réalisée. Les résultats identifient des manques importants de connaissances sur les sols dans les systèmes en AB et les besoins de recherche. Les 20 questions issues de ces échanges portent sur : i) le fonctionnement global des sols, plus particulièrement les grands cycles biogéochimiques Carbone, Azote, Phosphore (CNP), et les interactions biologiques ; ii) les effets à long terme des pratiques agricoles plus ou moins spécifiques aux systèmes en AB ; iii) la protection des sols ; et iv) les outils de diagnostic et de gestion des sols. La plupart des questions identifiées sont génériques et nécessitent des recherches multidisciplinaires, en particulier lorsqu’elles répondent à des enjeux systémiques. Le séminaire identifie des besoins en matière de dispositif et observatoire de recherche afin d’obtenir les références qui sont nécessaires pour valider ou adapter sur les systèmes en AB les outils et méthodes d’évaluation et de gestion des sols disponibles pour les systèmes agricoles conventionnels. Les principales questions identifiées lors du séminaire sont discutées et confrontées aux dynamiques récentes de la recherche et du développement sur les sols.
The agroecological transition of farms requires an in-depth change in advisory approaches, placing the farmer at the centre of a co-innovation and adaptive management approach. In this context, the ...main objective of the OUTILLAGE project was to close the gap in operational resources to support these new approaches, by developing tools to support farmers in their system change. Led by Terres Inovia, the project brought together 22 partners for 4 years. It relied on three farmer networks (Berry network, VIVESCIAgrosol club, AGRO D'OC group) to produce three types of tools: (i) dashboards applied to obtaining a robust rapeseed and to the success of sunflower in conservation agriculture, (ii) a decision tree applied to the transition to conservation agriculture, (iii) observation methods to feed these different tools. In this article we also describe the diversity of approaches to advising/supporting farmers and therefore the diversity of expectations in terms of tools and their uses, highlighted during the project. Finally, we propose a framework to help in the construction and use of personalised tools, to contribute to scale up these new approaches of innovation support.
La transition agroécologique des exploitations agricoles nécessite de faire évoluer en profondeur les approches de conseil, en plaçant l’agriculteur au centre d’une démarche de co-innovation et de gestion adaptative. Dans ce contexte, l’objectif principal du projet OUTILLAGE était de combler le manque de ressources opérationnelles pour soutenir ces nouvelles approches, en mettant au point des outils d’accompagnement des agriculteurs dans leur changement de système. Piloté par Terres Inovia, le projet a réuni 22 partenaires pendant 4 ans. Il s’est appuyé sur trois réseaux d’agriculteurs (réseau Berry, club VIVESCIAgrosol, groupe AGRO D’OC) pour produire trois types d’outils : (i) des tableaux de bord appliqués à l’obtention d’un colza robuste et à la réussite du tournesol en agriculture de conservation, (ii) un arbre de décision appliqué à la transition vers l’agriculture de conservation, (iii) des méthodes d’observation pour alimenter ces différents outils. Dans cet article, nous décrivons également la diversité des approches de conseil/accompagnement aux agriculteurs et donc la diversité d’attentes en termes d’outils et de leurs usages, mis en évidence au cours du projet. Enfin, nous proposons un cadre pour aider à la construction et l’usage d’outils personnalisés, afin de contribuer au déploiement de ces nouvelles approches d’accompagnement à l’innovation
In field crops, by the destruction of seeds and young seedlings, slug attacks are recognized as very harmful. This damage is often amplified in climatic conditions favorable to slugs and in the ...implementation of cultivation practices reducing the intensity of tillage. A large network of observations of more than 80 farmer plots and crop plant trials provided many data that were compared with information from other studies and literature. Slugs sampled from this network were studied in the laboratory in order to specify their thermotolerance and their biochemical composition during their growth. Data analysis provided details concerning the harmfulness of slugs, their life traits in fields cultivated during the seasons; the effects of different agricultural practices, beneficial organisms and weather conditions. This project contributed to the construction of a multicriteria assessment tool for slug risk and a conceptual model of slug population dynamics taking into account climatic factors. Nevertheless, their computer development remains to be made to make them available.
En grandes cultures, de par la destruction des semences et des jeunes plantules, les attaques de limaces sont reconnues comme très nuisibles. Ces dégâts sont souvent amplifiés lors de conditions climatiques favorables aux limaces et lors de la mise en oeuvre de pratiques culturales réduisant l’intensité du travail du sol. La mise en place d’un réseau conséquent d’observations de plus de 80 parcelles et au sein d’essais avec différents systèmes de cultures a fourni de nombreuses données qui ont été mises en regard avec des informations issues d’autres études et de la bibliographie. Des limaces extraites de ce réseau ont fait l’objet d’études au laboratoire permettant de préciser leur thermotolérance et leur composition biochimique au cours de leur croissance. L’analyse de l’ensemble des données apporte des précisions concernant : la nuisibilité des limaces, leurs traits de vie dans les champs cultivés au cours des saisons, les effets des différentes pratiques agricoles, de la faune auxiliaire et des conditions météorologiques. Ce projet a contribué à la construction d’un outil d’évaluation multicritère du risque limace et d’un modèle conceptuel de dynamique des populations de limaces tenant compte des facteurs climatiques. Néanmoins leur développement informatique reste à faire afin de les rendre disponibles.
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