Intensive agriculture has led to several drawbacks such as biodiversity loss, climate change, erosion, and pollution of air and water. A potential solution is to implement management practices that increase the level of provision of ecosystem services such as soil fertility and biological regulation. There is a lot of literature on the principles of agroecology. However, there is a gap of knowledge between agroecological principles and practical applications. Therefore, we review here agroecological and management sciences to identify two facts that explain the lack of practical applications: (1) the occurrence of high uncertainties about relations between agricultural practices, ecological processes, and ecosystem services, and (2) the site-specific character of agroecological practices required to deliver expected ecosystem services. We also show that an adaptive-management approach, focusing on planning and monitoring, can serve as a framework for developing and implementing learning tools tailored for biodiversity-based agriculture. Among the current learning tools developed by researchers, we identify two main types of emergent support tools likely to help design diversified farming systems and landscapes: (1) knowledge bases containing scientific supports and experiential knowledge and (2) model-based games. These tools have to be coupled with well-tailored field or management indicators that allow monitoring effects of practices on biodiversity and ecosystem services. Finally, we propose a research agenda that requires bringing together contributions from agricultural, ecological, management, and knowledge management sciences, and asserts that researchers have to take the position of "integration and implementation sciences."

Concerns about the negative impacts of productivist agriculture have led to the emergence of two forms of ecological modernisation of agriculture. The first, efficiency-substitution agriculture, aims to improve input use efficiency and to minimise environmental impacts of modern farming systems. It is currently the dominant modernisation pathway. The second, biodiversity-based agriculture, aims to develop ecosystem services provided by biological diversity. It currently exists only as a niche. Here we review challenges of implementing biodiversity-based agriculture: managing, at the local level, a consistent transition within and among farming systems, supply chains and natural resource management. We discuss the strengths and weaknesses of existing conceptual frameworks developed to analyse farming, socialecological and socio-technical systems. Then we present an integrative framework tailored for structuring analysis of agriculture from the perspective of developing a territorial biodiversity-based agriculture. In addition, we propose a participatory methodology to design this agroecological transition at the local level. This design methodology was developed to support a multi-stakeholder arena in analysing the current situation, identifying future exogenous changes and designing (1) targeted territorial biodiversity-based agriculture, (2) the pathway of the transition and (3) the required adaptive governance structures and management strategies. We conclude by analysing key challenges of designing such a complex transition, developing multi-actor and multidomain approaches based on a combination of scientific and experiential knowledge and on building suitable boundary objects (computer-based and conceptual models, indicators, etc.) to assess innovative systems designed by stakeholders.

In most current farming system classifications (e.g. "conventional" versus "organic"), each type of farming system encompasses a wide variety of farming practices and performances. Classifying farming systems using concepts such as "ecological", "sustainable intensification" or "agro-ecology" is not satisfactory because the concepts "overlap in…def-initions, principles and practices, thus creating…confusion in their meanings, interpretations and implications". Existing classifications most often focus either on biotechnical functioning or on socio-economic contexts of farming systems. We reviewed the literature to develop an original analytical framework of the diversity of farming systems and agriculture models that deal with these limits. To describe this framework, we first present the main differences between three biotechnical types of farming systems differing in the role of ecosystem services and external inputs: chemical input-, biological inputand biodiversity-based farming systems. Second, we describe four key socio-economic contexts which determine development and functioning of these farming systems: globalised commodity-based food systems, circular economies, alternative food systems and integrated landscape approaches. Third, we present our original analytical framework of agriculture models, defined as biotechnical types of farming systems associated with one or a combination of socio-economic contexts differing in the role of relationships based on global market prices and "territorial embeddedness". We demonstrate the potential of this framework by describing six key agriculture models and reviewing key scientific issues in agronomy associated with each one. We then analyse the added value of our analytical framework and its generic character. Lastly, we discuss transversal research issues of the agriculture models, concerning the technologies required, their function in the bioeconomy, their multi-criteria and multilevel assessments, their co-existence and the transitions between them.

Plant functional types (PFT) have been used to describe the response of native vegetation to environmental factors (i.e., fertility) and to livestock disturbance, but rarely under conditions of continuous grazing. In this work we investigate whether the longterm response of grassland communities submitted to a gradient of continuous grazing pressure can be described with such an approach. After 15 yr of differentiation of the grazing pressure applied to native grasslands we measured leaf dry-matter content (LDMC) and specific leaf area (SLA) of Poaceae populations of the communities. A grazing pressure gradient was created by levels of daily forage allowance: 4, 8, 12, and 16 kg of dry matter per day per 100 kg of animal live weight, monitored monthly. PFTs were defined by numerical analysis, where an algorithm finds the optimal trait subset based on the agreement between matrices of species 3 traits, paddocks 3 grass biomass, and environmental variables (levels of forage allowance and soil characteristics). The results show that it is possible to describe a gradient of grazing pressure by means of LDMC and/or SLA measured only on the Poacea contributing at least 80% of the total Poaceae biomass. Four PFTs were differentiated by these leaf traits. PFTs having low LDMC and high SLA are characteristic of high intensity of use and are made up largely of stoloniferous C 4 species typical of rapid resource capture strategies. Conversely, PFTs characterized by high LDMC and low SLA include species that are representative of low grazing pressure. Variations in the aggregate value of traits are due to changes in the species proportions and not to leaf-size adaptation as hypothesized. We conclude than in the absence of a gradient of fertility, plants with strategies of resource capture tend to be more represented under high grazing pressures. This situation results in a loss of functional diversity, but in particular a reduction in forage availability, which is incompatible with high animal production. Resumen La noción de grupos funcionales de plantas (GFP) ha sido utilizada para describir la respuesta de la vegetación nativa a los factores del medio (fertilidad) y al disturbio del pastoreo, pero pocos de dichos estudios han sido conducidos bajo condiciones de pastoreo continuo. En el presente trabajo se trata de verificar si dicho enfoque puede utilizarse para analizar la respuesta de la comunidad a un gradiente de presión de pastoreo continuo. Al te´rmino de 15 añ os de diferenciación continua de la presión de pastoreo ejercida sobre una pradera nativa, se midió el contenido de materia seca foliar (CMSF) y el área foliar específica (AFE) de las poblaciones de gramíneas presentes en la comunidad. El gradiente de pastoreo fue establecido según los niveles de oferta de forraje: 4, 8, 12, y 16 kg de materia seca por 100 kg de peso vivo por día, oferta ajustada mensualmente. Los GFP fueron definidos según un análisis numérico, donde un algoritmo identifica un subgrupo óptimo de características basado en la correspondencia e...

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In Western economies, several agriculture models coexist. For instance, intensive agriculture organization, which has increased yields while causing major pollution and resource depletion, competes with alternative models, which tackle these sustainability issues and lead to lower yields. An agronomical typology of current agriculture models in Western societies is proposed that describes multiple sustainability issues through an agroecological perspective. However, in order to choose between these agroecological pathways, we must understand their social structure and the principles underlying them. Thus, our purpose is to characterize the institutional aspects of the alternative models using socioeconomic convention theory. We conducted a series of workshops with specialists in the natural sciences (agronomy, landscape ecology, and entomology) and social sciences (economics and sociology) to describe sustainable agriculture models. This characterization revealed the values underlying six different sustainable agriculture models, their forms of organization, and the institutions governing them. We discuss the implications of the coexistence of these six models in light of sustainable transition issues. From this coexistence perspective, transition (i) refers to an intertwined process of legitimation and disqualification, and (ii) means seeing pathways as the multiplicity and degree of interconnection between models. Therefore, we (i) identified the elements in each model that legitimize its mode of organization, and (ii) disqualified the elements that are incompatible with the principles underlying the model's practices. Moreover, we emphasize that multiple transition pathways are possible based on complex, complementary combinations of different models. This revealed the intricate processes of competition and complementarity involving these models. Finally, our study on the coexistence, interdependence, and coevolution of multiple agriculture models led us to advocate a precautionary principle so that marginal innovative models are not prevented from emerging.

International audience1. Dry matter digestibility is a critical component of herbage nutritive value, a major service delivered by grasslands. The aim of this study was to test whether the dominance hypothesis applies to assess the impacts of environmental gradients and management regimes on thiscomponent of herbage nutritive value in permanent grasslands. 2. At the plant level, digestibility has been related to a number of functional traits, but whether this can be scaled up to the community level in species-rich grasslands and how such relationships are modulated by environmental conditions and management regimes remainunknown. Our primary objective was to test whether community-weighted means – species trait values weighted by the species abundance – of morphological, phenological and chemical traits could be used to explain variations in digestibility over a large range of climatic contexts,soil resource levels and management regimes. Our second objective was to explain variations in community digestibility within and among nine contrasting sites along large natural and man-induced environmental gradients.3. Over the whole data set, digestibility and most community-weighted means of traits responded to climatic factors and management regimes, but relations were not always significant when each site was considered separately. Community digestibility was significantly related to one or more plant traits within each site and to all of the measured traits when considering all the sites. Leaf dry matter content (LDMC) had the most consistent effects on digestibility, with a strikingly similar negative effect within each site. Potential evapotranspiration was negatively related to digestibility and contributed to explain a large part of the among-site variance. In addition, a low return interval of disturbance and a high disturbance intensity (biomass removal) were both associated with a high digestibility.4. Synthesis and applications. Disturbance regime, plant traits and local climate impacted dry matter digestibility roughly equally in grasslands. The effects of community composition on digestibility and its response to abiotic factors could be successfully captured by community weightedmeans of leaf dry matter content. This functional marker can be used to develop indicators and grassland management rules to support farmers in the refinement of their practices towards specific needs, such as target production outputs

Question: Are leaf dry matter content, specific leaf area and leaf life span relevant plant traits to discriminate the fertility gradient in species‐rich natural grasslands? In other words, is species ranking conserved when nitrogen availability or growing periods change? Location: Toulouse Research Centre, France; 150 m a.s.l. Methods: Fifteen grasses and nine dicotyledons were sown in pure stands in a random block design with three replicates. Each species was cultivated at two levels of nitrogen supply, limiting and non‐limiting for growth, with three replications per nitrogen level. Leaf traits were measured across both levels of nitrogen supply and growing periods over the year. Results: Leaf dry matter content values separated the species into three life‐form classes (grasses, rosette forbs and upright forbs, P < 0.001). This was not the case for specific leaf area and leaf life span. The three leaf traits were variable across growing periods and nitrogen levels, but the ranking of species was conserved over N‐levels and growth periods. Furthermore leaf dry matter content was always less variable than the other leaf traits. Conclusion: We conclude that leaf dry matter content measured only on grasses could be used as an indicator to describe the N‐richness of the habitat where native herbaceous vegetation develops.