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The paper proposes to carry out a preliminary analysis of the Italian food value chain based on the analysis of social agriculture, in particular social farms associated with “antimafia activities”. The analysis is based on the assumption that social agriculture is multifactorial. The text is based on three case studies from different Italian regions: Sicily, Campania and Lazio. The Sicilian farm is the most developed in terms of production sophistication; the small Campania farm gives great importance to non-commodity results, including well-being and landscape restoration; and the farm in Lazio offers a tangential response to the mafia's activities, although its managers carry out a form of direct resistance to the mafia in Rome. Le texte se propose de mener une analyse préliminaire de la chaîne de valeur de l’alimentation italienne à partir de l’analyse de l’agriculture sociale, en particulier les fermes sociales associées aux « activités antimafia ». L’analyse part du principe selon lequel l’agriculture sociale est multifactorielle. Le texte repose sur trois études de cas issues de régions italiennes différentes : la Sicile, la Campanie et le Latium. La ferme sicilienne est la plus développée en termes de sophistication de la production ; la ferme de Campanie, de petite taille, accorde une grande importance résultats non liés aux produits de base, notamment le bien-être et la restauration des paysages ; la ferme située dans le Latium, enfin, offre une réponse tangentielle aux activités de la mafia, bien que ses gestionnaires les définissent comme une forme de résistance directe à la mafia à Rome.

International audience; The management of genes conferring resistance to plant–pathogens should make it possible to control epidemics (epidemiological perspective) and preserve resistance durability (evolutionary perspective). Resistant and susceptible cultivars must be strategically associated according to the principles of cultivar mixture (within a season) and rotation (between seasons). We explored these questions by modeling the evolutionary and epidemiological processes shaping the dynamics of a pathogen population in a landscape composed of a seasonal cultivated compartment and a reservoir compartment hosting pathogen year-round. Optimal deployment strategies depended mostly on the molecular basis of plant–pathogen interactions and on the agro-ecological context before resistance deployment, particularly epidemic intensity and landscape connectivity. Mixtures were much more efficient in landscapes in which between-field infections and infections originating from the reservoir were more prevalent than within-field infections. Resistance genes requiring two mutations of the pathogen avirulence gene to be broken down, rather than one, were particularly useful when infections from the reservoir predominated. Combining mixture and rotation principles were better than the use of the same mixture each season as (i) they controlled epidemics more effectively in situations in which within-field infections or infections from the reservoir were frequent and (ii) they fulfilled the epidemiological and evolutionary perspectives.

1- The relative importance of local- and landscape-scale factors on butterfly diversity can depend on the quality, management intensity and landscape context of habitat patches. This study aims to disentangle these local and landscape effects on taxonomic and functional composition of butterfly communities within mosaic agricultural landscapes.2- We sampled butterflies in 144 grasslands and 142 linear elements (road verges and herbaceous strips between crops) in three regions in France. We analysed how local and landscape variables affected butterfly species richness, community composition and community-weighted mean traits.3- Local habitat variables explained more variation in butterfly richness and community composition than landscape-scale variables, both in grasslands and linear elements. Floristic composition was the most important predictor of butterfly community composition. In sites with tall vegetation and low biomass removal, butterfly communities were more dominated by species with long larval development, low fecundity and low mobility.4- Landscape variables were proportionally more influential in linear elements than in grasslands. Increasing landscape heterogeneity, by favouring agricultural mosaics with semi-natural grasslands and woodlands, appeared to be beneficial for butterflies, especially for specialist species.5- Agri-environmental schemes aiming at preserving butterfly diversity should thus primarily provide incentives to conserve or restore grasslands with low management intensity, while promoting at the same time landscape heterogeneity.

distance decay, habitat model, kernel, landscape buffer, landscape context, landscape extent, landscape management, landscape structure, scale of effect, spatial scale; To quantify the effect of the surrounding landscape context on a biological response at a site, most studies measure landscape variables within discs centred on this biological response (threshold-based method, TBM). This implicitly assumes that the effect of a unit area of the landscape is consistent up to a threshold distance beyond which it drops to zero. However, it seems more likely that the landscape effect declines with increasing distance from the biological response point. Here, we develop a method to quantify landscape context effects by weighting the landscape variables by functions that decrease with distance. We illustrate the method using abundance data on birds and insects, and compare the results to the threshold approach. We defined distance weighting functions by the function family (e.g. negative exponential, Gaussian…) and by the parameters for this function. We developed a method to simultaneously estimate the parameters characterizing the effect of the landscape variables and the parameters of the best weighting functions. For each test dataset, we determined which weighting function (family and parameters) had the most support, by optimizing the model AIC. The distance-weighted method (DWM) improved model support over the TBM in three of four datasets, with the exponential power function selected as the best weighing function in all three cases. The observed differences between estimations of landscape context effects by the distance-weighted and the threshold methods have significant implications for landscape management. For example, the DWM suggests that managing a landscape for 90% of its effect on a focal population requires an area over five times larger than the area estimated by the threshold method, a situation that might apply for priority conservation of few remnant populations of a severely endangered species. In contrast, management for 30% of the landscape effect requires only about half the area estimated using the threshold method, a situation that might apply to a management situation with limited resources or low political/societal support. The DWM is applicable to any species-habitat relationship. More comparisons are needed to determine the situations in which distance-weighted estimation of landscape context effects is warranted over the simpler threshold method.

International audience; Landscapes influence precipitation via the water vapor and energy fluxes they generate. Biologically active landscapes also generate aerosols containing microorganisms, some being capable of catalyzing ice formation and crystal growth in clouds at temperatures near 0 °C. The resulting precipitation is beneficial for the growth of plants and microorganisms. Mounting evidence from observations and numerical simulations support the plausibility of a bioprecipitation feedback cycle involving vegetated landscapes and the microorganisms they host. Furthermore, the evolutionary history of ice nucleation-active bacteria such as Pseudomonas syringae supports that they have been part of this process on geological time scales since the emergence of land plants. Elucidation of bioprecipitation feedbacks involving landscapes and their microflora could contribute to appraising the impact that modified landscapes have on regional weather and biodiversity, and to avoiding inadvertent, negative consequences of landscape management.

PICLÉG': a "research, development and stakeholders" all-together initiative for integrated production of field vegetables in France. 3. International Symposium on Horticulture in Europe, SHE2016

International audience; The efficiency of the European Union’s Common Agricultural Policy in mitigating the negative effects of agricultural intensification on the landscape and biodiversity is increasingly being questioned. Enhancing a reciprocal understanding of various stakeholders’ mental models of agro-social-ecosystems has been proposed to trigger changes in both policy design and farmers’ behaviors. However, the relationship between farmers’ mental models and practices is rarely considered. Here, we explore the relationship between farmers’ individual mental models (IMMs) of the agricultural landscape and their land management practices. To do so, we developed a theoretical and methodological framework grounded in cognitive psychology and farming system research for eliciting and comparing IMMs and land management practices. We applied this framework in the Coteaux de Gascogne territory, a hilly crop-livestock region in southern France. We identified groups of farmers according to their cropland and semi-natural habitat management practices. The results of our quantitative and qualitative comparisons of mental models between farmer groups showed that the way of farming partly relates to farmers’ ways of thinking about the landscape and highlighted the heterogeneity of IMMs between and within farmer groups. We found evidence that path-dependent factors that constrain farmers’ practices can modify their mental models, e.g., the role of agricultural machinery. Our study illustrates how an interdisciplinary framework coupling mental models and farming systems approaches provides an opportunity to enhance our understanding of the relationships between farmers’ world views and their practices. Moreover, our results challenge current ways of thinking and designing biodiversity conservation policies in farmed landscapes.

Complex landscape management instruments based on a dynamic, innovative land-conservation paradigm and spatial zoning to provide for graded intensity of protection and human use are being implemented in the newer generation of biosphere reserves and biosphere parks. The multifunctionality of these exemplary landscapes with sustainable development is a great challenge; it also offers considerable potential for conflict. This paper intends to demonstrate the extent to which multifunctionality has been realised in the alpine Großes Walsertal Biosphere Park, and how the local population perceive the quality of their park five years after it was created. Landscape management efforts in the Großes Walsertal were monitored by accompanying regional-economic and perceptional studies, resulting in a discussion of required future actions.Des instruments complexes de gestion du paysage, fondés sur un paradigme dynamique et innovant de conservation ainsi que sur un zonage de l’espace visant à réguler la protection du territoire et son utilisation par l’homme, ont été mis en œuvre dans la dernière génération de réserves de biosphère et de parcs. La multifonctionnalité de ces paysages exemplaires du développement durable constitue un défi majeur, mais représente également une importante source de conflits. L’objectif de cet article est de démontrer dans quelle mesure la notion de multifonctionnalité a été appliquée à la réserve de biosphère alpine de Grosse Walsertal et d’évaluer comment la population locale perçoit la qualité de son parc, cinq ans après sa création. Les efforts de gestion du paysage dans la réserve de Grosse Walsertal ont été évalués par des études économiques régionales et par des enquêtes de perception, à l’origine d’un débat sur les actions futures à mettre en place.

Complex landscape management instruments based on a dynamic, innovative land-conservation paradigm and spatial zoning to provide for graded intensity of protection and human use are being implemented in the newer generation of biosphere reserves and biosphere parks. The multifunctionality of these exemplary landscapes with sustainable development is a great challenge; it also offers considerable potential for conflict. This paper intends to demonstrate the extent to which multifunctionality has been realised in the alpine Großes Walsertal Biosphere Park, and how the local population perceive the quality of their park five years after it was created. Landscape management efforts in the Großes Walsertal were monitored by accompanying regional-economic and perceptional studies, resulting in a discussion of required future actions.Des instruments complexes de gestion du paysage, fondés sur un paradigme dynamique et innovant de conservation ainsi que sur un zonage de l’espace visant à réguler la protection du territoire et son utilisation par l’homme, ont été mis en œuvre dans la dernière génération de réserves de biosphère et de parcs. La multifonctionnalité de ces paysages exemplaires du développement durable constitue un défi majeur, mais représente également une importante source de conflits. L’objectif de cet article est de démontrer dans quelle mesure la notion de multifonctionnalité a été appliquée à la réserve de biosphère alpine de Grosse Walsertal et d’évaluer comment la population locale perçoit la qualité de son parc, cinq ans après sa création. Les efforts de gestion du paysage dans la réserve de Grosse Walsertal ont été évalués par des études économiques régionales et par des enquêtes de perception, à l’origine d’un débat sur les actions futures à mettre en place.

Sustainable management of agricultural landscapes is a strong social, ecological and economic challenge. Favouring the different ecosystem services provided by these complex systems, characterized by a strong patio-temporal variability linked to human activity, is by now crucial. The work developed in this thesis has focused on pest population regulation services, by developing spatialized models in order to identify the interactions between the landscape and populations in the context of an integrated management of the agricultural landscape. The conceptual approach we used is based on careful selection of the levels of organization and spatio-temporal scales which lead to the development of two embedded models: an agricultural landscape simulator (ATLAS) reproducing the spatial-temporal variability of habitats and a cellular automaton describing the pluriannual dynamics of a cereal aphid: Rhopalosiphum padi. A statistical analysis of the results highlighted the effects of different landscape parameters (composition and climate) on aphid densities at different spatial scales throughout the seasons. The potential effects of plausible management scenarios were also evaluated. Amongst our results, we identify the replacement of corn by sorghum in the south-western part of France to potentially lead to higher aphid densities within the landscape in spring, which is a season specifically sensible to infestations. We replace this work in the larger context of favouring ecosystem services and propose new ideas for a sustainable management of agricultural landscapes., La gestion agroécologique durable des paysages agricoles constitue un très fort enjeu social, écologique et économique. Favoriser les différents services écosystémiques que fournissent ces systèmes complexes, caractérisés par une forte variabilité spatio-temporelle liée aux activités anthropiques, est désormais crucial. Le travail développé dans cette thèse s’est focalisé sur les services de régulation des populations de ravageurs, en développant des modèles spatialisés destinés à identifier les interactions entre paysage et populations dans l’optique d’une gestion intégrée du paysage agricole. L’approche conceptuelle utilisée s’est appuyée sur une réflexion sur les choix de niveaux d’organisation et d’échelles spatio-temporelles pertinentes qui a conduit au développement de deux modèles imbriqués: un simulateur de paysages agricoles (ATLAS) reproduisant la variabilité spatio-temporelle des habitats et un automate cellulaire décrivant les dynamiques pluriannuelles d’un puceron des céréales: Rhopalosiphum padi. Une analyse statistique des résultats a permis d’identifier l’effet des différents paramètres du paysage (composition et climat) sur les densités de pucerons à différentes échelles spatiales au cours des saisons. Ont également été évalués les effets potentiels de différents scénarios de gestion plausibles au sein du paysage agricole étudié. Parmi nos résultats, nous identifions que le remplacement du maïs par le sorgho dans le sud-ouest de la France pourrait conduire à une augmentation des densités de R.padi au sein du paysage au printemps, période particulièrement sensible aux infestations. Nous replaçons ce travail dans le cadre plus large de la favorisation des services écosystémiques et apportons des premiers éléments de réflexion pour une gestion durable du paysage agricole.

After the second World War, socio-economic developments and the spread of the chestnut blight meant that many of the heavily used chestnut orchards in southern Switzerland were left without any management. In the absence of cultural inputs, the anthropogenic origin of the stands became less apparent and their structures tended to disintegrate. A hierarchical approach was used to study the changes in stand characteristics over time. The species composition, structure and percent cover of the stands were studied at medium level using aerial photographs, with particular regard to medium term (35 years) changes. On a smaller scale, dendroecological methods were used to investigate the timing and ecology of the regeneration and growth of both invading and orchard trees. The results show clearly that the chestnut orchards were invaded by a large variety of species, which varied according to site conditions. These powerful natural dynamics are due to both the open structure of the chestnut orchards and the lack of resilience shown by the orchard-trees when suddenly submitted to natural competition. The main factors influencing the evolution of these stands are presented and discussed. A better understanding of these kinds of evolutionary processes is a prerequisite if future forest and landscape management is to be sustainable., L'évolution socio-économique qui a suivi la seconde guerre mondiale et la propagation du chancre de l'écorce du châtaignier ont entraîné, en Suisse méridionale, l'abandon de nombre de châtaigneraies pourtant intensément utilisées jusque-là. En l'absence de soins culturaux, l'origine anthropogène de ces peuplements s'est estompée et leurs structures se sont désagrégées. Les changements qui se sont produits à la longue au niveau des caractéristiques des peuplements ont été analysés au moyen d'une approche hiérarchique. La composition en espèces des peuplements, leur structure ainsi que leur taux de recouvrement ont été étudiés à moyenne échelle à l'aide de photographies aériennes prenant spécialement en compte les changements à moyen terme (35 ans). A une échelle plus précise, des méthodes dendro-écologiques ont été employées pour examiner la durée et l'écologie de la régénération et de la croissance des châtaigniers ainsi que des essences apparaissant spontanément. Les résultats montrent clairement que les châtaigneraies ont été envahies par un grand nombre d'espèces variant suivant les conditions stationnelles. Cette dynamique naturelle puissante peut se développer grâce à la structure ouverte des châtaigneraies et à la faible plasticité des châtaigniers face à la soudaine concurrence naturelle. Les principaux éléments qui influencent l'évolution de ces vergers sont présentés et traités. Une meilleure compréhension de ces processus évolutifs est indispensable pour une gestion durable des forêts et des paysages du futur., Conedera Marco, Stanga Pietro, Lischer Christian, Stöckli Veronika. Competition and dynamics in abandoned chestnut orchards in southern Switzerland. In: Ecologia mediterranea, tome 26,2000. pp. 101-112.

National audience

The deployment of virus resistant crops often leads to the emergence of resistancebreaking pathogens that suppress the yield benefit provided by resistances. The theoretical analyses presented here are designed to provide guidelines for farmers aiming altogether to optimise the deployment of a resistant cultivar in a landscape over several years according to management strategies aiming either to minimise the overall yield losses due to the virus (economical strategy) or to keep the frequency of the resistance-breaking virus in the reservoir hosts under a preset threshold (patrimonial strategy). Assuming gene-for-gene interactions, epidemics are modelled by linking genetic and epidemiological processes in a landscape composed of a mosaic of resistant and susceptible fields, subjected to seasonality, and of a reservoir hosting viruses year round. We explored how time constant optimal cropping ratio (i.e. the proportion of resistance cultivar deployed in a landscape) defined according to either economical or patrimonial objectives depend on resistant cultivar choice and on landscape epidemiological context (defined by the landscape structure and the mean epidemic incidence observed before resistance deployment). If the choice of the resistance gene is the main factor determining optimal cropping ratio, epidemiological contexts are also important. In some of them, patrimonial and economical strategies have close economical efficiencies, implying that both management objectives are achievable at the same time. In others, patrimonial strategies have weak economical efficiencies, meaning that both management objectives are incompatible. A way to remove such incompatibility is to design time varying strategies where the proportion of resistant fields in the landscape can change. Indeed, such strategies can at the same time comply with a patrimonial objective while substantially restoring the economical efficiency of time constant strategies and can even over performed them in landscape where epidemics are primarily driven by between fields infection events.

Le gène Vat confère au melon une résistance à la colonisation par le puceron Aphis gossypii ainsi qu'une résistance aux phytovirus non persistants (CMV, WMV,...) transmis par ces pucerons (Lecoq et al., 1979; Pitrat & Lecoq, 1982 ; Boissot et al., 2010). Il est toutefois inefficace pour bloquer la transmission des virus portés par les autres espèces de pucerons. L'utilisation de Vat est donc généralement couplée à des traitements aphicides afin de limiter la transmission virale par les pucerons non colonisateurs du melon. Or, la réduction progressive de l'usage des produits phytosanitaires dans la protection des cultures imposée par l'évolution de la réglementation (plan Eco-Phyto 2018) conduit à rechercher de nouvelles stratégies permettant d'accompagner la lutte génétique pour la gestion des bio-agresseurs. La bibliographie suggère que l'implantation de bandes de plantes non hôtes (enherbées ou fleuries) à la périphérie des cultures pourrait être une option efficace pour diminuer 1) la pression puceron (et donc le risque de contournement de Vat) en favorisant le développement des ennemis naturels (Pfiffner & Wyss, 2004) et 2) la pression virus en constituant notamment un filtre réduisant la charge virale des pucerons avant qu'ils n'atteignent les cultures (Hooks & Fereres, 2006). L'hypothèse testée dans ce projet est qu'un aménagement adéquat de l'environnement parcellaire peut contribuer à réguler les populations de pucerons et/ou leur potentiel virulifère et ainsi à réduire le risque d'épidémies virales. L'effet de trois types d'aménagement (sol nu, bandes enherbées et bandes fleuries) sur l'efficacité de la résistance médiée par le gène Vat est évalué au champ.

International audience; The deployment of resistant crops often leads to the emergence of resistance-breaking pathogens that suppress the yield benefit provided by the resistance. Here, we theoretically explored how farmers' main leverages (resistant cultivar choice, resistance deployment strategy, landscape planning and cultural practices) can be best combined to achieve resistance durability while minimizing yield losses as a result of plant viruses. Assuming a gene-for-gene type of interaction, virus epidemics are modelled in a landscape composed of a mosaic of resistant and susceptible fields, subjected to seasonality, and a reservoir hosting viruses year-round. The model links the genetic and the epidemiological processes, shaping at nested scales the demogenetic dynamics of viruses. The choice of the resistance gene (characterized by the equilibrium frequency of the resistance-breaking virus at mutation-selection balance in a susceptible plant) is the most influential leverage of action. Our results showed that optimal strategies of resistance deployment range from 'mixture' (where susceptible and resistant cultivars coexist) to 'pure' strategies (with only resistant cultivar) depending on the resistance characteristics and the epidemiological context (epidemic incidence and landscape connectivity). We demonstrate and discuss gaps concerning virus epidemiology across the agro-ecological interface that must be filled to achieve sustainable disease management.

Wetlands were during à long time proscribed and destroyed in France. They become now biological heritage of general interest. Technics of marsh management allow to restore and to sustain their biological potentiality. In the cultural context of the "forêt de Rambouillet", near Paris, their esthetical visibility is perceive only as "picturesque" or "wild". This type of relationship to space and nature can only be enhanced with a appropriate landscape project. It is suggested here to invent a modern project of visibility and communication of biological sanctuaries managed by french forestry commission. This project must be both ecological and poetical., Longtemps proscrits et détruits, les milieux palustres deviennent aujourd'hui en France des patrimoines éco-biologiques d'intérêt général. Les techniques de gestion paludicole permettent de réhabiliter et de perpétuer leur potentiel biologique. Néanmoins, dans le contexte culturel de la forêt de Rambouillet, à l'Ouest de Paris, leur visibilité esthétique ne semble possible que sur le mode de l'appréciation pittoresque ou sauvage. Bien qu'il soit possible, sous condition de l'existence d'un projet de paysage approprié, de construire cette relation esthétique à l'espace et à la nature, il est suggéré dans cette communication d'inventer un projet moderne de visibilité et de communication des réserves biologiques domaniales à la fois écologique et poétique., Donadieu Pierre. La paludiculture au pays des grenouilles bleues ? (Esthetical visibility and ecological management in the wetlands of the Rambouillet's forest, Yvelines, France). In: Bulletin de l'Association de géographes français, 71e année, 1994-3 ( juin). Les marais continentaux de la France des plaines et des moyennes montagnes. Aspects écologiques et sociologiques, gestion et protection, sous la direction de Marcel Bournerias et Bertrand Sajaloli. pp. 242-249.