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Agroecological principles and elements and their implications for transitioning to sustainable food systems. A review
No full textInternational audienceAbstractThere is consensus that the global food system is not delivering good nutrition for all and is causing environmental degradation and loss of biodiversity, such that a profound transformation is needed to meet the challenges of persistent malnutrition and rural poverty, aggravated by the growing consequences of climate change. Agroecological approaches have gained prominence in scientific, agricultural and political discourse in recent years, suggesting pathways to transform agricultural and food systems that address these issues. Here we present an extensive literature review of concepts, definitions and principles of agroecology, and their historical evolution, considering the three manifestations of agroecology as a science, a set of practices and a social movement; and relate them to the recent dialogue establishing a set of ten iconic elements of agroecology that have emerged from a global multi-stakeholder consultation and synthesis process. Based on this, a consolidated list of principles is developed and discussed in the context of presenting transition pathways to more sustainable food systems. The major outcomes of this paper are as follows. (1) Definition of 13 consolidated agroecological principles: recycling; input reduction; soil health; animal health; biodiversity; synergy; economic diversification; co-creation of knowledge; social values and diets; fairness; connectivity; land and natural resource governance; participation. (2) Confirmation that these principles are well aligned and complementary to the 10 elements of agroecology developed by FAO but articulate requirements of soil and animal health more explicitly and distinguish between biodiversity and economic diversification. (3) Clarification that application of these generic principles can generate diverse pathways for incremental and transformational change towards more sustainable farming and food systems. (4) Identification of four key entry points associated with the elements: diversity; circular and solidarity economy; co-creation and sharing of knowledge; and, responsible governance to enable plausible pathways of transformative change towards sustainable agriculture and food systems
Long-term effects of selection for prolificacy and kit growth on rabbit performance and behaviour
No full textVisio-conférenceInternational audienc
Vers des systèmes de culture agroécologiques - Usage des couverts végétaux semés ou spontanés comme cultures de services dans les vignobles – Comment raisonner leur pilotage en viticulture ?
No full textInternational audienceLa viticulture doit faire face à différents enjeux agronomiques et environnementaux, sous peine de voir sa durabilité menacée. La protection des sols est notamment un enjeu majeur pour la durabilité des vignobles [1-4], car ils sont un élément clé pour la production viticole et constitutif du concept de terroir [5-7]. Le changement climatique affecte également la viticulture et impose de penser à des pratiques alternatives [8,9].Les services écosystémiques correspondent aux avantages socio-économiques retirés par l’homme de son utilisation durable des fonctions écologiques des écosystèmes [10]. Les écosystèmes agricoles ont un objectif clairement identifié de produire de la nourriture, des fibres et de l’énergie (services d’approvisionnement). Pour autant, ils sont susceptibles de fournir d’autres services de régulation et conservation ou culturels (figure 1) qui dépendent des fonctions écologiques réalisées par les organismes [10,11]. Les « cultures de services » (CDS) sont cultivées dans les vignobles pour la fourniture de services écosystémiques non marchands. Dit autrement, elles ne sont ni récoltées ni exportées de la parcelle, mais restituées au sol. Les CDS permettent de protéger les sols de l’érosion, de réguler les populations d’adventices et ravageurs, de réguler les maladies, d’augmenter l’infiltration de l’eau dans les sols et d’améliorer leur qualité, d’assurer leur portance, d’entretenir leur biodiversité, et de contribuer à la séquestration de carbone [12-16]. L’association de couverts végétaux avec la vigne peut également générer une compétition pour les ressources du sol [17-19]. Les risques de stress et de perte de rendement de la vigne associés sont souvent les premières raisons de non-adoption de cette pratique. Ils dépendent fortement du contexte technique et pédoclimatique des vignobles [20-22]. En ce sens, la forte variabilité des pratiques au sein des régions viticoles révèle de nombreuses incertitudes quant à la gestion des CDS pour satisfaire les objectifs de production et les services environnementaux [20, 23]. Le terme « cultures de services » permet de souligner l’importance de considérer ces communautés de plantes comme des cultures à part entière à piloter pour obtenir les compromis recherchés. L’objectif de cet article est de proposer un cadre d’analyse pour le pilotage des CDS dans les vignobles. Nous discutons ici de l’équilibre entre services et dysservices et leur dépendance au contexte, ainsi qu’aux leviers de pilotage dont disposent les viticulteurs et viticultrices
European conformation and fat scores of bovine carcasses are not good indicators of marbling
No full textInternational audienceMarbling is one of the primary carcass attributes utilized in most beef grading systems for eating quality evaluation. In Europe, the current beef grading system is the EUROP grid, which is focused on carcass commercial value and production yield rather than eating quality estimation. The aim of this study was to investigate the relationship between marbling and the most common scores for carcass classification in Europe. If there are strong associations between marbling and European classification scores, marbling score may be estimated from the carcass characteristics. However, this study indicated that European classification scores explain only a slight proportion of the variance in marbling score (32%, 46%, 34% and 21% for the entire cattle group, young bulls, females and steers, respectively). Therefore, whereas the EUROP grid is well adapted to estimate yield, it does not reflect marbling at all. The European beef industry should take into account additional indicators related to beef palatability to assist the determination of the commercial value of carcasses
Intercropping impacts the host location behaviour and population growth of aphids
No full textInternational audienceIncreasing intrafield plant diversity has been shown to regulate pest populations in various agroecosystems. Among the suggested mechanisms for this bottom-up pest control, the disruptive crop hypothesis states that herbivores' abilities to locate and colonize their host plants are reduced by the presence of non-host plants. Under laboratory conditions, we evaluated how intercropping wheat and legumes modifies the behaviour of apterous cereal aphids, Sitobion avenae (Fabricius) (Hemiptera: Aphididae), in terms of host plant location and population growth. We compared two intercropping systems – soft winter wheat, Triticum aestivum L. (Poaceae), associated with winter pea, Pisum sativum L., or with white clover, Trifolium repens L. (both Fabaceae) – and sole stands of soft winter wheat. Aphids needed more time to locate their wheat host plant and then spent less time on wheat when it was intercropped with clover. At the population level, and accounting for host plant biomass, only intercropping wheat with clover significantly reduced aphid densities on wheat, as this was particularly disruptive to S. avenae behaviour and population growth. Our laboratory study points out that the species used as non-host plants and their density are important parameters that should be taken into account in field studies on intercropping systems
Inefficiency of cutting stems once during the vegetative growth of Fallopia spp.
No full textInternational audienceThe management of some invasive plant species is difficult because species can exhibit high productivity despite control measures. Inefficient control methods may even produce unwanted side effects. We conducted an experimental study on Fallopia spp., a major invasive plant in Europe. We tested the effects of two different stem-cutting frequencies on the aboveground and belowground traits of several genotypes in a greenhouse experiment against control plants (no cuts). Plants receiving one cut per month for a total of 4 cuts experienced 30% mortality of the individuals, surviving plants had greatly reduced values of the measured traits, especially for biomass and height. In contrast, plants in the treatment group, consisting of a single cut in five months, were eventually able to compensate for the loss of aboveground parts despite reduced length and biomass of the rhizome. Our results indicate that minimal mechanical intervention has limited effects on Fallopia spp. During the vegetative season, managers can increase control efficacy through regular cutting rather than a one-time intervention for these species
Students’ knowledge and expectations about sustainable food systems in higher education
No full textInternational audiencePurpose : To clarify needs and requests of the young generation to the contemporary and future education on food systems, this paper aims to examine the following issues: students’ background knowledge, students’ behaviour as consumers and food citizenship, most interesting topics of SFS for students and students’ preferences and expectations in developing different skills, topics and preferences in teaching/learning methods. Design/methodology/approach : This study was performed as an online-survey amongst eight European Universities in seven European Union (EU) countries to which 1,122 students responded. Data was analysed with descriptive and multivariate statistical analyses. Findings : Taste and Health are the most important values and motives that influence students’ food buying and consumption decisions, but significant differences were found amongst students from different universities and countries. The most important topics for students for future teaching courses are “organic food”, “fair trade”, “organic agriculture” and most important skills to learn are “ability to make a judgement and justify decisions” and the “ability to create and innovate”. Excursions and field trips as teaching methods was given the highest ranks. Research limitations/implications : Different study programmes and cultural backgrounds of the participating students in the different universities could be a limiting factor for the interpretation of some results. Originality/value : These results provide a basis for improvement of higher education in the EU towards sustainable food systems based on experiential learning/teaching methods
Gestion du paysage en faveur du réseau écologique. : Modes de gouvernance, représentations et pratiques dans les espaces agricoles
No full textBiodiversity conservation no longer only concerns protected areas. It is also a matter of ecological network. Ecological corridors between habitats participate in the circulation of animal and plant populations. This new perspective extends the scope of conservation to ordinary nature and areas where ecological processes and human activities are strongly intertwined, such as agricultural areas. This study focuses on the implementation of integrated biodiversity conservation in agricultural areas through landscape management for ecological network. We study the modes of governance, representations and practices on several scales, mixing qualitative and quantitative analyses. At the national and regional scales, changes in social representations of the relationship between agriculture and biodiversity are examined with a content analysis of French media. At the regional and local scale, we compare, in three case studies, the modes of governance of a contractual tool of the French ecological network policy: the Green and Blue infrastructure ("Trame verte et bleue"). For this purpose, we use semi-structured interviews and participant observations. At farm scale, we identify with semi-structured interviews, the ways in which biodiversity can be included as a factor in decision–making practices, and we investigate the farmers’ representations of biodiversity and landscape elements. We show the importance of taking into account the diversity of conceptions and representations of landscape by farmers and all stakeholders for successful integrated biodiversity conservation. In the design and implementation of ecological network policies, the predominant conception of landscape is ecological and therefore has difficulty in including the agricultural issues and farmers’ views. Finally, we discuss the theoretical, methodological and practical implications of our results in conservation geography.Les politiques de conservation de la biodiversité ne concernent plus seulement aujourd’hui des espaces protégés, mais également des réseaux où l’enjeu est de préserver et restaurer les continuités entre habitats afin de favoriser les circulations des populations animales et végétales. Ce nouveau regard élargit les territoires de la conservation aux espaces de nature ordinaire, tels que les espaces agricoles, où les processus écologiques et les activités humaines sont fortement imbriqués. Ce travail de thèse s’intéresse à la mise en œuvre, à travers une gestion du paysage en faveur du réseau écologique, d’une stratégie de conservation intégrée de la biodiversité dans les espaces agricoles. Pour cela, nous étudions les modes de gouvernance, les représentations et les pratiques de cette conservation à différentes échelles par des approches associant méthodes d’analyse qualitative et quantitative. A l’échelle nationale et régionale, nous interrogeons les évolutions des représentations sociales des relations entre agriculture et biodiversité au moyen d’une analyse de contenu de la presse quotidienne. A l’échelle régionale et territoriale, nous comparons la gouvernance et la mise en œuvre d’un outil contractuel de la politique Trame verte et bleue sur trois études de cas, à partir d’entretiens semi-directifs et d’observations participantes. A l’échelle de l’exploitation agricole, nous identifions par des entretiens semi-directifs, les modalités d’intégration de la biodiversité comme facteur de décision des pratiques des agriculteurs et leurs représentations de la biodiversité et des éléments semi-naturels arborés. Nos résultats mettent en évidence que le paysage est un outil propice à l’insertion de la biodiversité dans les espaces agricoles, et à celle des acteurs locaux dans la conservation, à condition qu’il soit considéré dans sa pluralité de conceptions et de représentations. Cependant, autour des réseaux écologiques, la notion de paysage qui fait référence reste largement celle de l’écologie et celle-ci peine à inclure la dimension agricole et les agriculteurs. Nous discutons des apports théoriques et méthodologiques de ces résultats et de leurs perspectives scientifiques et appliquées en géographie de la conservation
