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Coordonnée par le Cirad en partenariat avec INRAE et l'IRD, l'étude ≪ 4 pour 1000 ≫ Outre-mer dresse un bilan inédit des stocks de carbone du sol des territoires ultramarins. Les auteurs formulent des recommandations opérationnelles et de recherche pour preserver ces stocks élevés et répondre aux grands enjeux actuels de l'agriculture face au changement climatique au niveau national et territorial. Si le potentiel des sols métropolitains a fait l'objet d'une evaluation en 2019, celui des territoires ultramarins était jusqu'ici méconnu. Dans le cadre de la présente étude, les auteurs dressent pour la premiere fois un état des lieux des connaissances pour la Guadeloupe, la Martinique, la Guyane, La Reunion, Mayotte, Saint-Martin et Saint-Barthélemy.

Bioeconomic models make it possible to assess ex-ante the consequences of public interventions in the agriculture sector. Yet since policymakers rarely participate in their design or use, these models are often too complex or do not address their questions. This article describes the implementation of a nine-step participatory modelling process involving regional policymakers, and analyses the contribution of this process to the cross-brainstorming between policymakers and researchers. In the preliminary stage, researchers develop a prototype bioeconomic model which links the farm level, where trade-offs between productions are considered, with the regional level, where the balance between production and consumption per product is considered. Public actors are then mobilised to identify issues and characterise the scenarios that can be used to explore the questions selected. The scenarios are simulated with the bioeconomic model, which evolves depending on the needs, and the outputs are discussed with the public actors. The method was applied in La Réunion (France) on the design and assessment of aid mechanisms related to the development of organic farming. The results showed (i) which farms convert to organic farming according to aid amounts, (ii) how local demand per product is satisfied and (iii) what are the amounts of the ensuing budgets for subsidies. The approach proved to be relevant for exchanging knowledge between public actors and researchers, regarding in particular innovative farming systems, farm diversity and multi-criteria evaluation of policy choices. The simulated scenarios offered powerful support for discussions about market evolutions and environmental challenges. These results indicate that transparent modelling tools and long-term partnerships with policymakers are required to implement such an approach at the regional scale.

[EN] This project aims to study the dynamic population of pests and natural enemies in a farming system that is based on agroecology and bio-inputs. The farming system (micro-farm) covers a superficial of 7000 m2 and is situated in the island of Guadeloupe in Lesser Antilles. It has been designed with mixed plants that provide multiple services to the ecosystem. One of these services is to attract natural enemies that can regulate the pest populations. This study will focus on Hymenoptera parasitoids, one of the main group of natural enemies, widely used in biological control of pests. The population of parasitoids and their interaction with flower species and pests will be analyzed in the micro- farm. The main objective is to identify the parasitoids Hymenoptera, ants and pests and to understand which flower species attracts higher population of parasitoids. This knowledge will be used to promote conservation biological control as part of integrated pest management and to recommend to the farmers to allow flowers in the farm in order to attract beneficials insects and to create a balance agroecosystem. The goal is to prove that multiple cropping system can be used as reservoir for the survival of parasitoids and other beneficial that can regulate pest populations decreasing the use of chemicals., [ES] Este proyecto tiene como objetivo estudiar la dinámica poblacional de plagas y enemigos naturales en un sistema agrícola basado en principos agroecológicos y bioinsumos. El sistema de cultivo (micro-granja) cubre una superficie de 7.000 m2 y está situado en la isla de Guadalupe en las Antillas Menores. Ha sido diseñado con diversidad de especies de plantas que proporcionan múltiples servicios al ecosistema. Uno de estos servicios ecosistémicos consiste en atraer enemigos naturales que podrían regular las poblaciones plaga. Este estudio se centra en los himenópteros parasitoides, uno de los principales grupos de enemigos naturales, ampliamente usado en control biológico de plagas. Se analizará la población de parasitoides y su interacción con las plagas y las especies de plantas presentes en la micro-granja. El principal objetivo consiste en identificar los himenópteros parasitoides, hormigas y plagas para determinar qué especies de plantas atrae mayor población de parasitoides. Este conocimiento será utilizado para potenciar el control biológico por conservación como una parte del control integrado de plagas y recomendar a los agricultores que permitan la presencia de plantas con flores en la granja para atraer insectos beneficiosos y crear un agroecosistema equilibrado. El objetivo es demostrar que los sistemas de cultivos múltiples pueden usarse como reservorio de parasitoides y otros beneficiosos que pueden regular las poblaciones de plagas y disminuir el uso de fitosanitarios.

[EN] This project aims to study the dynamic population of pests and natural enemies in a farming system that is based on agroecology and bio-inputs. The farming system (micro-farm) covers a superficial of 7000 m2 and is situated in the island of Guadeloupe in Lesser Antilles. It has been designed with mixed plants that provide multiple services to the ecosystem. One of these services is to attract natural enemies that can regulate the pest populations. This study will focus on Hymenoptera parasitoids, one of the main group of natural enemies, widely used in biological control of pests. The population of parasitoids and their interaction with flower species and pests will be analyzed in the micro- farm. The main objective is to identify the parasitoids Hymenoptera, ants and pests and to understand which flower species attracts higher population of parasitoids. This knowledge will be used to promote conservation biological control as part of integrated pest management and to recommend to the farmers to allow flowers in the farm in order to attract beneficials insects and to create a balance agroecosystem. The goal is to prove that multiple cropping system can be used as reservoir for the survival of parasitoids and other beneficial that can regulate pest populations decreasing the use of chemicals., [ES] Este proyecto tiene como objetivo estudiar la dinámica poblacional de plagas y enemigos naturales en un sistema agrícola basado en principos agroecológicos y bioinsumos. El sistema de cultivo (micro-granja) cubre una superficie de 7.000 m2 y está situado en la isla de Guadalupe en las Antillas Menores. Ha sido diseñado con diversidad de especies de plantas que proporcionan múltiples servicios al ecosistema. Uno de estos servicios ecosistémicos consiste en atraer enemigos naturales que podrían regular las poblaciones plaga. Este estudio se centra en los himenópteros parasitoides, uno de los principales grupos de enemigos naturales, ampliamente usado en control biológico de plagas. Se analizará la población de parasitoides y su interacción con las plagas y las especies de plantas presentes en la micro-granja. El principal objetivo consiste en identificar los himenópteros parasitoides, hormigas y plagas para determinar qué especies de plantas atrae mayor población de parasitoides. Este conocimiento será utilizado para potenciar el control biológico por conservación como una parte del control integrado de plagas y recomendar a los agricultores que permitan la presencia de plantas con flores en la granja para atraer insectos beneficiosos y crear un agroecosistema equilibrado. El objetivo es demostrar que los sistemas de cultivos múltiples pueden usarse como reservorio de parasitoides y otros beneficiosos que pueden regular las poblaciones de plagas y disminuir el uso de fitosanitarios.

Biomass is a promising renewable alternative to decarbonize and to secure energy production on small islands, as most insular power generation systems rely heavily on imported fossil fuels. Feedstock procurement is a key aspect of bioenergy chain sustainability, and local resources as well as imported biomass can be considered if the electricity generated presents environmental benefits. We used Life Cycle Assessment (LCA) to evaluate the environmental impacts of 1 kWh of electricity produced in Guadeloupe from the combustion of locally grown energy cane and imported wood pellets. The energy cane agricultural supply was simulated using a bio-economic model to elaborate and analyze five scenarios involving different biomass mixes and geographical areas of production. Our results show that electricity produced from energy cane reduced the impacts of ABIOTIC DEPLETION, ACIDIFICATION and PHOTOCHEMICAL OXIDATION by 29% compared with pellet-based electricity. The environmental impacts of the energy cane cultivation stage varied by a factor of 1.5–3.7 among regional areas of cultivation because of differences in yields, soil emissions and land conversion for energy crop farming. The substitution of 5% of fossil energy by biomass in the island electricity mix can reduce GLOBAL WARMING and ABIOTIC DEPLETION impact by 4.5%. However, this change requires 3.5 to 5.2 times higher LAND OCCUPATION per unit of energy produced. Given the limited land availability on small islands, this latter point confirms that the combination of locally grown energy crops with imported biomass will be a suitable strategy to develop sustainable bioenergy for small islands.

Farm modelling has been widely used over the past ten years for the assessment of agricultural systems in face of policy changes, technological innovation, economic and climate changes. Beyond the various modelling methods (optimisation, rule-based, agent-based...), these models are framed by their objectives -defining input data and users- which can be: policy assessment, technological innovation assessment, farming systems resilience studies, optimisation of water management at regional level, agricultural landscape design, a " boundary object " for strategic thinking in a stakeholder arena. Indeed these farm modelling tools are still poorly used for the design of innovative cropping systems which remains mostly based on field level experiments and modelling. Nevertheless driving forces and assessment criteria for the design of sustainable cropping systems are increasingly expressed at larger scales than field or even farm. For exemple most environmental services are provisionned at landscape (e.g. biodiversity) or whatershed levels (e.g. water quality), at regional level (e.g. climate mitigation) and in more global socio-systems (e.g. food security, rural development). On the other hand, a large part of the functions supporting these services are operating at field level where the interactions between farmer's decisions (crop selection, combination and management) and biophysical processes (soil, plants, pests, weeds and diseases) are occuring. A large part of these biophysical processes also occur at landscape level (biodiversity, water flows…) but they require information at field level to be upscaled in a landscape mosaïc. In-between these two levels (field and region) the farm level plays a key role in agricultural systems simulation: (i) it is the decision level of farm activities (crops, livestock, trees…) further applied to field level ; (ii) it is the first level of expression of socio-economical services (labour, income, food production…) and (iii) farm

Biomass is a promising renewable alternative to decarbonize and to secure energy production on small islands, as most insular power generation systems rely heavily on imported fossil fuels. Feedstock procurement is a key aspect of bioenergy chain sustainability, and local resources as well as imported biomass can be considered if the electricity generated presents environmental benefits. We used Life Cycle Assessment (LCA) to evaluate the environmental impacts of 1 kWh of electricity produced in Guadeloupe from the combustion of locally grown energy cane and imported wood pellets. The energy cane agricultural supply was simulated using a bio-economic model to elaborate and analyze five scenarios involving different biomass mixes and geographical areas of production. Our results show that electricity produced from energy cane reduced the impacts of ABIOTIC DEPLETION, ACIDIFICATION and PHOTOCHEMICAL OXIDATION by 29% compared with pellet-based electricity. The environmental impacts of the energy cane cultivation stage varied by a factor of 1.5–3.7 among regional areas of cultivation because of differences in yields, soil emissions and land conversion for energy crop farming. The substitution of 5% of fossil energy by biomass in the island electricity mix can reduce GLOBAL WARMING and ABIOTIC DEPLETION impact by 4.5%. However, this change requires 3.5 to 5.2 times higher LAND OCCUPATION per unit of energy produced. Given the limited land availability on small islands, this latter point confirms that the combination of locally grown energy crops with imported biomass will be a suitable strategy to develop sustainable bioenergy for small islands.

Biomass is a promising renewable alternative to decarbonize and to secure energy production on small islands, as most insular power generation systems rely heavily on imported fossil fuels. Feedstock procurement is a key aspect of bioenergy chain sustainability, and local resources as well as imported biomass can be considered if the electricity generated presents environmental benefits. We used Life Cycle Assessment (LCA) to evaluate the environmental impacts of 1 kWh of electricity produced in Guadeloupe from the combustion of locally grown energy cane and imported wood pellets. The energy cane agricultural supply was simulated using a bio-economic model to elaborate and analyze five scenarios involving different biomass mixes and geographical areas of production. Our results show that electricity produced from energy cane reduced the impacts of ABIOTIC DEPLETION, ACIDIFICATION and PHOTOCHEMICAL OXIDATION by 29% compared with pellet-based electricity. The environmental impacts of the energy cane cultivation stage varied by a factor of 1.5–3.7 among regional areas of cultivation because of differences in yields, soil emissions and land conversion for energy crop farming. The substitution of 5% of fossil energy by biomass in the island electricity mix can reduce GLOBAL WARMING and ABIOTIC DEPLETION impact by 4.5%. However, this change requires 3.5 to 5.2 times higher LAND OCCUPATION per unit of energy produced. Given the limited land availability on small islands, this latter point confirms that the combination of locally grown energy crops with imported biomass will be a suitable strategy to develop sustainable bioenergy for small islands.

Farm modelling has been widely used over the past ten years for the assessment of agricultural systems in face of policy changes, technological innovation, economic and climate changes. Beyond the various modelling methods (optimisation, rule-based, agent-based...), these models are framed by their objectives -defining input data and users- which can be: policy assessment, technological innovation assessment, farming systems resilience studies, optimisation of water management at regional level, agricultural landscape design, a " boundary object " for strategic thinking in a stakeholder arena. Indeed these farm modelling tools are still poorly used for the design of innovative cropping systems which remains mostly based on field level experiments and modelling. Nevertheless driving forces and assessment criteria for the design of sustainable cropping systems are increasingly expressed at larger scales than field or even farm. For exemple most environmental services are provisionned at landscape (e.g. biodiversity) or whatershed levels (e.g. water quality), at regional level (e.g. climate mitigation) and in more global socio-systems (e.g. food security, rural development). On the other hand, a large part of the functions supporting these services are operating at field level where the interactions between farmer's decisions (crop selection, combination and management) and biophysical processes (soil, plants, pests, weeds and diseases) are occuring. A large part of these biophysical processes also occur at landscape level (biodiversity, water flows…) but they require information at field level to be upscaled in a landscape mosaïc. In-between these two levels (field and region) the farm level plays a key role in agricultural systems simulation: (i) it is the decision level of farm activities (crops, livestock, trees…) further applied to field level ; (ii) it is the first level of expression of socio-economical services (labour, income, food production…) and (iii) farm

In West and Central Africa and in the Caribbean, yam is one of the most important sources of carbohydrates and has a great potential to improve food security. The yam production sector is, however, now challenged by the satisfaction of evolving consumers' preferences. Since little is known about consumers' preferences regarding yams' characteristics, product quality, and the drivers of yam purchase, six focus group discussions were conducted (for a total of 31 participants). Among the purchasing criteria, price was considered more important than the others. It was followed by the external damage, the origin, and the size of the tuber. The most frequently cited consumption criteria were the taste, the texture, and color of flesh after cooking. Taste was considered more important than the other criteria. Three consumers' profiles were established reflecting heterogeneity in preferences, especially as concerns the willingness to pay for yam and consumption habits. They were designated as the Hedonistic, the Thrifty and the Flexible. Our results suggest that innovations can be implemented to sustain and stimulate the development of the yam sector in Guadeloupe. Two main development paths were identified. The first path is the valorization of the great existing diversity of yam varieties and the increase in the level of information for consumers about product attributes such as the cooking mode, the origin, and the mode of production. Building a marketing strategy based on the valorization of this diversity can help maintain and preserve yam's agro-biodiversity and the satisfaction of rapidly evolving consumption habits. The second path is the definition of yam ideotypes that suit consumers' needs. We expect that tailoring the production to consumers' needs will have a positive impact on global food security in the Caribbean region.

In West and Central Africa and in the Caribbean, yam is one of the most important sources of carbohydrates and has a great potential to improve food security. The yam production sector is, however, now challenged by the satisfaction of evolving consumers' preferences. Since little is known about consumers' preferences regarding yams' characteristics, product quality, and the drivers of yam purchase, six focus group discussions were conducted (for a total of 31 participants). Among the purchasing criteria, price was considered more important than the others. It was followed by the external damage, the origin, and the size of the tuber. The most frequently cited consumption criteria were the taste, the texture, and color of flesh after cooking. Taste was considered more important than the other criteria. Three consumers' profiles were established reflecting heterogeneity in preferences, especially as concerns the willingness to pay for yam and consumption habits. They were designated as the Hedonistic, the Thrifty and the Flexible. Our results suggest that innovations can be implemented to sustain and stimulate the development of the yam sector in Guadeloupe. Two main development paths were identified. The first path is the valorization of the great existing diversity of yam varieties and the increase in the level of information for consumers about product attributes such as the cooking mode, the origin, and the mode of production. Building a marketing strategy based on the valorization of this diversity can help maintain and preserve yam's agro-biodiversity and the satisfaction of rapidly evolving consumption habits. The second path is the definition of yam ideotypes that suit consumers' needs. We expect that tailoring the production to consumers' needs will have a positive impact on global food security in the Caribbean region.

Interest in renewable energy from agricultural biomass has increased in recent years. Among renewable energy sources, biomass is considered indeed as an attractive option for sustainable energy production. This is particularly true in the case of small tropical island states, where energy demand is increasing and the energy mix currently heavily relies on fossil imported resources. Diversifying and orientating the energy mix toward locally grown energy crops could therefore be a promising sustainable option. However, the introduction of such bioenergy systems under existing conditions and current agricultural models is still rather uncertain and requires achieving several sustainable goals. In order to build new sustainable energy systems, assessing the conditions for a sustainable and profitable biomass supply is a critical step prior to industrial investment. In this paper we present the results of an interdisciplinary research program aimed at identifying the agro-environmental, economic and industrial conditions for producing electricity from energy cane in Guadeloupe.

Loss of varietal diversity is a worldwide challenge to crop species at risk for genetic erosion, while the loss of biological resources may hinder future breeding objectives. Loss of varieties has been mostly investigated in traditional agricultural systems where variety numbers are dramatically high, or for most economically important crop species for which comparison between pre-intensive and modern agriculture was possible. Varietal dynamics, i.e., turnover, or gains and losses of varieties by farmers, is nevertheless more rarely studied and while we currently have good estimates of genetic or varietal diversity for most crop species, we have less information as to how on farm agro-diversity changes and what cause its dynamics. We therefore investigated varietal dynamics in the agricultural yam system in the Caribbean island of Guadeloupe. We interviewed producers about varieties they cultivated in the past compared to their current varieties, in addition to characterizing yam cropping characteristics and both farm level and producers socio-economic features. We then used regression tree analyses to investigate the components of yam agro-diversity, varietal dynamics and impact of anthracnose on varieties. Our data demonstrated that no dramatic loss of varieties occurred within the last decades. Cultivation changes mostly affected widespread cultivars while frequency of uncommon varieties stayed relatively stable. Varietal dynamics nevertheless followed sub-regional patterns, and socio-economic influences such as producer age or farm crop diversity. Recurrent anthracnose epidemics since the 1970s did not alter varietal dynamics strongly, but sometimes translated into transition from Dioscorea alata to less susceptible species or into a decrease of yam cultivation. Factors affecting changes in agro-diversity were not relating to agronomy in our study, and surprisingly there were different processes delineating short term from long term varietal dynamics, independen

As one of the largest users of pesticides in the world, banana production is responsible for numerous types of pollution affecting water, soil and air and causing a variety of health issues. Agroecological innovations can help to reduce pesticide use and achieve cleaner and more sustainable banana production systems. Innovations must be well suited to the diversity of banana farms and acceptable to the stakeholders involved in production. We tested the impact of 18 agroecological innovations in Guadeloupe on the sustainability of three contrasted production systems, using the multi-criteria assessment model MASC. These innovations included different types of fallow (A), bans on pesticides (B), conditional applications of pesticides (C), intercropping (D), resistant cultivars (E), and integrated systems (F). In the assessment, we introduced the views of 29 stakeholders involved in sustainability issues relative to banana grouped through three sets of weightings, obtained by direct weighting of the indicators used in a multi-criteria assessment tool. We analysed the effects of each set of weightings on the sustainability level for these different banana production systems. Our results showed that the adoption of innovations can have negative, positive or no effects on the overall sustainability of banana production systems. Although none of the innovations had a positive effect on all cropping systems, some innovations were relevant to several farm types. However, this depended on the sets of weightings considered, because we found several types of stakeholder with opposing views on the importance of sustainability components. Integrated and organic systems produced the best results in terms of increasing sustainability and were relevant to current farming systems. However, in order to obtain cleaner banana production at the landscape scale, a combination of these innovations, tailored to the diversity of farmers' situations and stakeholder preferences, still needs to

As one of the largest users of pesticides in the world, banana production is responsible for numerous types of pollution affecting water, soil and air and causing a variety of health issues. Agroecological innovations can help to reduce pesticide use and achieve cleaner and more sustainable banana production systems. Innovations must be well suited to the diversity of banana farms and acceptable to the stakeholders involved in production. We tested the impact of 18 agroecological innovations in Guadeloupe on the sustainability of three contrasted production systems, using the multi-criteria assessment model MASC. These innovations included different types of fallow (A), bans on pesticides (B), conditional applications of pesticides (C), intercropping (D), resistant cultivars (E), and integrated systems (F). In the assessment, we introduced the views of 29 stakeholders involved in sustainability issues relative to banana grouped through three sets of weightings, obtained by direct weighting of the indicators used in a multi-criteria assessment tool. We analysed the effects of each set of weightings on the sustainability level for these different banana production systems. Our results showed that the adoption of innovations can have negative, positive or no effects on the overall sustainability of banana production systems. Although none of the innovations had a positive effect on all cropping systems, some innovations were relevant to several farm types. However, this depended on the sets of weightings considered, because we found several types of stakeholder with opposing views on the importance of sustainability components. Integrated and organic systems produced the best results in terms of increasing sustainability and were relevant to current farming systems. However, in order to obtain cleaner banana production at the landscape scale, a combination of these innovations, tailored to the diversity of farmers' situations and stakeholder preferences, still needs to

As one of the largest users of pesticides in the world, banana production is responsible for numerous types of pollution affecting water, soil and air and causing a variety of health issues. Agroecological innovations can help to reduce pesticide use and achieve cleaner and more sustainable banana production systems. Innovations must be well suited to the diversity of banana farms and acceptable to the stakeholders involved in production. We tested the impact of 18 agroecological innovations in Guadeloupe on the sustainability of three contrasted production systems, using the multi-criteria assessment model MASC. These innovations included different types of fallow (A), bans on pesticides (B), conditional applications of pesticides (C), intercropping (D), resistant cultivars (E), and integrated systems (F). In the assessment, we introduced the views of 29 stakeholders involved in sustainability issues relative to banana grouped through three sets of weightings, obtained by direct weighting of the indicators used in a multi-criteria assessment tool. We analysed the effects of each set of weightings on the sustainability level for these different banana production systems. Our results showed that the adoption of innovations can have negative, positive or no effects on the overall sustainability of banana production systems. Although none of the innovations had a positive effect on all cropping systems, some innovations were relevant to several farm types. However, this depended on the sets of weightings considered, because we found several types of stakeholder with opposing views on the importance of sustainability components. Integrated and organic systems produced the best results in terms of increasing sustainability and were relevant to current farming systems. However, in order to obtain cleaner banana production at the landscape scale, a combination of these innovations, tailored to the diversity of farmers' situations and stakeholder preferences, still needs to

Interest in renewable energy from agricultural biomass has increased in recent years. Among renewable energy sources, biomass is considered indeed as an attractive option for sustainable energy production. This is particularly true in the case of small tropical island states, where energy demand is increasing and the energy mix currently heavily relies on fossil imported resources. Diversifying and orientating the energy mix toward locally grown energy crops could therefore be a promising sustainable option. However, the introduction of such bioenergy systems under existing conditions and current agricultural models is still rather uncertain and requires achieving several sustainable goals. In order to build new sustainable energy systems, assessing the conditions for a sustainable and profitable biomass supply is a critical step prior to industrial investment. In this paper we present the results of an interdisciplinary research program aimed at identifying the agro-environmental, economic and industrial conditions for producing electricity from energy cane in Guadeloupe.

Loss of varietal diversity is a worldwide challenge to crop species at risk for genetic erosion, while the loss of biological resources may hinder future breeding objectives. Loss of varieties has been mostly investigated in traditional agricultural systems where variety numbers are dramatically high, or for most economically important crop species for which comparison between pre-intensive and modern agriculture was possible. Varietal dynamics, i.e., turnover, or gains and losses of varieties by farmers, is nevertheless more rarely studied and while we currently have good estimates of genetic or varietal diversity for most crop species, we have less information as to how on farm agro-diversity changes and what cause its dynamics. We therefore investigated varietal dynamics in the agricultural yam system in the Caribbean island of Guadeloupe. We interviewed producers about varieties they cultivated in the past compared to their current varieties, in addition to characterizing yam cropping characteristics and both farm level and producers socio-economic features. We then used regression tree analyses to investigate the components of yam agro-diversity, varietal dynamics and impact of anthracnose on varieties. Our data demonstrated that no dramatic loss of varieties occurred within the last decades. Cultivation changes mostly affected widespread cultivars while frequency of uncommon varieties stayed relatively stable. Varietal dynamics nevertheless followed sub-regional patterns, and socio-economic influences such as producer age or farm crop diversity. Recurrent anthracnose epidemics since the 1970s did not alter varietal dynamics strongly, but sometimes translated into transition from Dioscorea alata to less susceptible species or into a decrease of yam cultivation. Factors affecting changes in agro-diversity were not relating to agronomy in our study, and surprisingly there were different processes delineating short term from long term varietal dynamics, independen

As one of the largest users of pesticides in the world, banana production is responsible for numerous types of pollution affecting water, soil and air and causing a variety of health issues. Agroecological innovations can help to reduce pesticide use and achieve cleaner and more sustainable banana production systems. Innovations must be well suited to the diversity of banana farms and acceptable to the stakeholders involved in production. We tested the impact of 18 agroecological innovations in Guadeloupe on the sustainability of three contrasted production systems, using the multi-criteria assessment model MASC. These innovations included different types of fallow (A), bans on pesticides (B), conditional applications of pesticides (C), intercropping (D), resistant cultivars (E), and integrated systems (F). In the assessment, we introduced the views of 29 stakeholders involved in sustainability issues relative to banana grouped through three sets of weightings, obtained by direct weighting of the indicators used in a multi-criteria assessment tool. We analysed the effects of each set of weightings on the sustainability level for these different banana production systems. Our results showed that the adoption of innovations can have negative, positive or no effects on the overall sustainability of banana production systems. Although none of the innovations had a positive effect on all cropping systems, some innovations were relevant to several farm types. However, this depended on the sets of weightings considered, because we found several types of stakeholder with opposing views on the importance of sustainability components. Integrated and organic systems produced the best results in terms of increasing sustainability and were relevant to current farming systems. However, in order to obtain cleaner banana production at the landscape scale, a combination of these innovations, tailored to the diversity of farmers' situations and stakeholder preferences, still needs to

Agroecosystems represent 38 % of global land use. Agroecosystems are located close to human settlements and are managed to produce food and fibers, traded in markets. Agroecosystems also produce other goods and services essential to human beings, such as climate regulation, flood mitigation, and landscape amenity. Economists and ecologists have developed the ecosystem services framework to foster the provision of these non-commercial services. Scientists can therefore help decision makers to develop sustainable ecosystems by studying ecosystem services. Here, we analyze the trade-offs of ecosystem services of farming systems. We discuss case studies of mixed perennial crops. The set of ecosystem services provided by these agroecosystems depends on their composition, structure, and management. Complex rule-based management will be required if winegrowers are to maintain an adequate set of ecosystem services across contrasting climatic years. Innovations including cover crops in banana systems can fulfill most of the objective set but will rely on increased farm labor. We then discuss the advantages, challenges, and opportunities to include the description of relations between ecosystem services in cropping system design. We propose to extend the yield gap analysis to ecosystem services, as a service gap analysis. This extension faces methodological questions about the potential provision of a service in a region. We conclude on the challenges that need to be faced if we want to use ecosystem services trade-offs to improve the contribution of agricultural systems to human well-being. (Résumé d'auteur)

Ensuring the success of agriculture is at the heart of food security, and it is necessary to examine strategies that tackle agricultural development through the production and consumption of sustainable food products. One way to increase food security in small island states is to develop local food sectors by increasing consumers’ awareness about local products with sustainable characteristics. We designed an economic experiment to assess consumers’ willingness-to-pay (WTP) for yams with sustainable characteristics: the origin, the intrinsic quality of an alternative variety and the mode of production. The results showed that labelling significantly changes consumers’ valuation of the different yam profiles. Consumers’ WTP for local yams (2.85 € kg-1) was significantly higher than for imported yams (1.80 € kg-1), while the organic mode of production derives a significant premium if information on production methods has been disseminated. The results also suggested that organoleptic characteristics of new varieties should not be overlooked. We conclude on how the labelling strategy could be facilitated through a policy targeting the development of the local food sector.

Ensuring the success of agriculture is at the heart of food security, and it is necessary to examine strategies that tackle agricultural development through the production and consumption of sustainable food products. One way to increase food security in small island states is to develop local food sectors by increasing consumers’ awareness about local products with sustainable characteristics. We designed an economic experiment to assess consumers’ willingness-to-pay (WTP) for yams with sustainable characteristics: the origin, the intrinsic quality of an alternative variety and the mode of production. The results showed that labelling significantly changes consumers’ valuation of the different yam profiles. Consumers’ WTP for local yams (2.85 € kg-1) was significantly higher than for imported yams (1.80 € kg-1), while the organic mode of production derives a significant premium if information on production methods has been disseminated. The results also suggested that organoleptic characteristics of new varieties should not be overlooked. We conclude on how the labelling strategy could be facilitated through a policy targeting the development of the local food sector.

Ensuring the success of agriculture is at the heart of food security, and it is necessary to examine strategies that tackle agricultural development through the production and consumption of sustainable food products. One way to increase food security in small island states is to develop local food sectors by increasing consumers’ awareness about local products with sustainable characteristics. We designed an economic experiment to assess consumers’ willingness-to-pay (WTP) for yams with sustainable characteristics: the origin, the intrinsic quality of an alternative variety and the mode of production. The results showed that labelling significantly changes consumers’ valuation of the different yam profiles. Consumers’ WTP for local yams (2.85 € kg-1) was significantly higher than for imported yams (1.80 € kg-1), while the organic mode of production derives a significant premium if information on production methods has been disseminated. The results also suggested that organoleptic characteristics of new varieties should not be overlooked. We conclude on how the labelling strategy could be facilitated through a policy targeting the development of the local food sector.

La chlordécone (CLD), molécule organochlorée, persiste dans les sols des bananeraies où elle a été appliquée entre 1972 et 1993. Elle contaminera eaux, végétaux et population pour de nombreuses décennies. Le projet RivAGE aborde notamment la question de la gestion de cette pollution à travers la production et l'accompagnement d'innovations pour réduire l'exposition des populations et les impacts environnementaux associés aux usages de la CLD. Une première étape est d'aboutir à une représentation partagée des relations de "causes à effets" entre l'homme et l'environnement. Pour cela, le projet s'intéressera aux composantes physiques, biologiques, écologiques, socio-économiques de l'environnement. Une seconde étape consiste à identifier les innovations qui permettront de mieux gérer le risque de pollution et à accompagner les acteurs dans leur mise en oeuvre. Les observations sont conduites à l'échelle de deux sites ateliers, l'un en Guadeloupe, l'autre en Martinique. Les résultats escomptés sont à la fois des connaissances nouvelles sur la pollution par la CLD et aussi des produits opérationnels (modèles, pratiques agricoles...) qui contribueront à réduire l'exposition des populations et des écosystèmes.

La chlordécone (CLD), molécule organochlorée, persiste dans les sols des bananeraies où elle a été appliquée entre 1972 et 1993. Elle contaminera eaux, végétaux et population pour de nombreuses décennies. Le projet RivAGE aborde notamment la question de la gestion de cette pollution à travers la production et l'accompagnement d'innovations pour réduire l'exposition des populations et les impacts environnementaux associés aux usages de la CLD. Une première étape est d'aboutir à une représentation partagée des relations de "causes à effets" entre l'homme et l'environnement. Pour cela, le projet s'intéressera aux composantes physiques, biologiques, écologiques, socio-économiques de l'environnement. Une seconde étape consiste à identifier les innovations qui permettront de mieux gérer le risque de pollution et à accompagner les acteurs dans leur mise en oeuvre. Les observations sont conduites à l'échelle de deux sites ateliers, l'un en Guadeloupe, l'autre en Martinique. Les résultats escomptés sont à la fois des connaissances nouvelles sur la pollution par la CLD et aussi des produits opérationnels (modèles, pratiques agricoles...) qui contribueront à réduire l'exposition des populations et des écosystèmes.

Parce qu'elle est basée en premier lieu sur l'utilisation de l'espace (de la parcelle au bassin versant), parce que les limites de parcelle restent impuissantes à arrêter les flux de matière, l'agriculture reste un élément clé de la gestion des milieux anthropisés et naturels. A travers sa relation à son environnement, l'agriculture constitue de fait un élément d'ingénierie écologique incontournable. Les questions liées aux pesticides en sont un témoignage exemplaire : (1) d'une part en raison de la gravité des impacts environnementaux générés (2) et d'autre part en raison des fortes injonctions à " l'écologisation " des pratiques. A l'interface entre agronomie et écologie, se pose la question de la contribution d'une ingénierie agroécologique à la gestion du milieu. On pose l'hypothèse que la connaissance des mécanismes de dispersion et de contamination des êtres vivants à l'échelle du bassin versant, en surface comme en souterrain, peut permettre d'identifier les processus écologiques à optimiser (fonction de rétention, séquestration... ) et les pratiques agricoles correspondantes pour préserver les ressources sols et eaux. C'est ce qu'étudie le projet RIvAGE dans le cas des Antilles qui associent une pollution sans précédent et des systèmes diversifiés. L'agriculture joue sur les processus de dispersion des polluants. Les pratiques agricoles interfèrent sur les apports (sources), les processus de rétention (stockage), de dégradation et de mobilisation par les eaux. Une première étape sera d'acquérir des connaissances sur les processus de contamination du milieu. Les processus suivants seront observés : rétention des polluants dans les sols, (re)mobilisation dans la solution du sol, transfert et impacts vers les cultures et les écosystèmes aquatiques (eau et animaux). Un système d'information permettra de regrouper puis de diffuser les connaissances produites auprès des ingénieurs de l'agroécologie. Une seconde étape sera alors d'identifier différentes innovations

Parce qu'elle est basée en premier lieu sur l'utilisation de l'espace (de la parcelle au bassin versant), parce que les limites de parcelle restent impuissantes à arrêter les flux de matière, l'agriculture reste un élément clé de la gestion des milieux anthropisés et naturels. A travers sa relation à son environnement, l'agriculture constitue de fait un élément d'ingénierie écologique incontournable. Les questions liées aux pesticides en sont un témoignage exemplaire : (1) d'une part en raison de la gravité des impacts environnementaux générés (2) et d'autre part en raison des fortes injonctions à " l'écologisation " des pratiques. A l'interface entre agronomie et écologie, se pose la question de la contribution d'une ingénierie agroécologique à la gestion du milieu. On pose l'hypothèse que la connaissance des mécanismes de dispersion et de contamination des êtres vivants à l'échelle du bassin versant, en surface comme en souterrain, peut permettre d'identifier les processus écologiques à optimiser (fonction de rétention, séquestration... ) et les pratiques agricoles correspondantes pour préserver les ressources sols et eaux. C'est ce qu'étudie le projet RIvAGE dans le cas des Antilles qui associent une pollution sans précédent et des systèmes diversifiés. L'agriculture joue sur les processus de dispersion des polluants. Les pratiques agricoles interfèrent sur les apports (sources), les processus de rétention (stockage), de dégradation et de mobilisation par les eaux. Une première étape sera d'acquérir des connaissances sur les processus de contamination du milieu. Les processus suivants seront observés : rétention des polluants dans les sols, (re)mobilisation dans la solution du sol, transfert et impacts vers les cultures et les écosystèmes aquatiques (eau et animaux). Un système d'information permettra de regrouper puis de diffuser les connaissances produites auprès des ingénieurs de l'agroécologie. Une seconde étape sera alors d'identifier différentes innovations

Food sectors have to face lots of hurdles today and their sustainability is called into question. We present here an original method that we developed to analyze the yam (Dioscorea sp.) food sector in Guadeloupe (FWI) and devise recommendations for its sustainable development. This three-step method aims at giving an overview of the sector by describing and analyzing the strategies and expectations of farmers, retailers and consumers. This overview makes it possible then to draw conclusions for improving the sustainability of the sector. In the first step we enquired yam farmers in order to characterize their productive strategies. We identified six different types of farms according to the importance placed on yam for income generation. In the second step we focused on marketing chains. We found that local yam is mostly traded informally via five main distribution chains that reflect farmers and retailers’ strategies. In the third step, we focused on yam consumers in order to identify ways to boost yam consumption. Focus group discussions helped us to identify the determinants of yam consumption and to devise hypotheses about ways to increase it. We then tested those hypotheses through a laboratory experiment in which we elicited consumers’ willingness to pay for different types of market signals: i) the intrinsic quality of a variety resistant to pathogens and of high testing quality, ii) a label about the local origin, iii) a label about the organic production. Our results showed that consumers were ready to pay a premium for the local and organically grown yam. We then discussed the interest of moving onto a certification scheme for the different types of farms and agents identified in the first and second stage. This study suggests that a way to improve the sustainability of the yam sector in Guadeloupe would be to mobilize farmers around acollective product qualification strategy.

Food sectors have to face lots of hurdles today and their sustainability is called into question. We present here an original method that we developed to analyze the yam (Dioscorea sp.) food sector in Guadeloupe (FWI) and devise recommendations for its sustainable development. This three-step method aims at giving an overview of the sector by describing and analyzing the strategies and expectations of farmers, retailers and consumers. This overview makes it possible then to draw conclusions for improving the sustainability of the sector. In the first step we enquired yam farmers in order to characterize their productive strategies. We identified six different types of farms according to the importance placed on yam for income generation. In the second step we focused on marketing chains. We found that local yam is mostly traded informally via five main distribution chains that reflect farmers and retailers’ strategies. In the third step, we focused on yam consumers in order to identify ways to boost yam consumption. Focus group discussions helped us to identify the determinants of yam consumption and to devise hypotheses about ways to increase it. We then tested those hypotheses through a laboratory experiment in which we elicited consumers’ willingness to pay for different types of market signals: i) the intrinsic quality of a variety resistant to pathogens and of high testing quality, ii) a label about the local origin, iii) a label about the organic production. Our results showed that consumers were ready to pay a premium for the local and organically grown yam. We then discussed the interest of moving onto a certification scheme for the different types of farms and agents identified in the first and second stage. This study suggests that a way to improve the sustainability of the yam sector in Guadeloupe would be to mobilize farmers around acollective product qualification strategy.

Cultiver de la canne dédiée à la production électrique a-t-il un intérêt? Dans certains contextes spécifiques, comme en Guadeloupe sur les sols pollués à la chlordécone, une filière canne dédiée à la production électrique pourrait être une solution alternative à la production alimentaire rendue délicate sur ces sols. Elle constituerait aussi un atout pour améliorer l'autonomie énergétique de l'île. Toutefois, une telle filière doit également présenter un intérêt environnemental pour la collectivité ainsi qu'un intérêt économique pour ses futures parties prenantes (agriculteurs, industriels et usagers). Une démarche est proposée pour évaluer la rentabilité économique de cette filière et son intérêt environnemental. Elle comprend trois volets interdépendants : l'analyse de l'acceptabilité par les agriculteurs de cette nouvelle filière, l'analyse des conditions de sa rentabilité économique et son évaluation environnementale via la méthodologie de l'Analyse de Cycle de Vie. L'article se focalise sur les méthodes et les outils développés spécifiquement pour évaluer différents scénarios d'organisation de filières. A titre illustratif, les outils ont été utilisés pour tester deux scénarios hypothétiques, portant sur un cas d'étude en Guadeloupe. L'évaluation de ces scénarios se fait à la lumière des performances agronomiques, économiques et environnementales depuis la production du matériel végétal jusqu'à sa combustion. Elle permet de mettre en évidence quelques paramètres déterminants de la faisabilité de cette filière en cours d'étude. Cette étude a été réalisée dans le cadre du programme de recherche REBECCA (REcherche Biomasse Energie Canne dans la région de CApesterre) mené par le Cirad en partenariat avec un industriel (Cann'elec Développement) et l'INRA.

Cultiver de la canne dédiée à la production électrique a-t-il un intérêt? Dans certains contextes spécifiques, comme en Guadeloupe sur les sols pollués à la chlordécone, une filière canne dédiée à la production électrique pourrait être une solution alternative à la production alimentaire rendue délicate sur ces sols. Elle constituerait aussi un atout pour améliorer l'autonomie énergétique de l'île. Toutefois, une telle filière doit également présenter un intérêt environnemental pour la collectivité ainsi qu'un intérêt économique pour ses futures parties prenantes (agriculteurs, industriels et usagers). Une démarche est proposée pour évaluer la rentabilité économique de cette filière et son intérêt environnemental. Elle comprend trois volets interdépendants : l'analyse de l'acceptabilité par les agriculteurs de cette nouvelle filière, l'analyse des conditions de sa rentabilité économique et son évaluation environnementale via la méthodologie de l'Analyse de Cycle de Vie. L'article se focalise sur les méthodes et les outils développés spécifiquement pour évaluer différents scénarios d'organisation de filières. A titre illustratif, les outils ont été utilisés pour tester deux scénarios hypothétiques, portant sur un cas d'étude en Guadeloupe. L'évaluation de ces scénarios se fait à la lumière des performances agronomiques, économiques et environnementales depuis la production du matériel végétal jusqu'à sa combustion. Elle permet de mettre en évidence quelques paramètres déterminants de la faisabilité de cette filière en cours d'étude. Cette étude a été réalisée dans le cadre du programme de recherche REBECCA (REcherche Biomasse Energie Canne dans la région de CApesterre) mené par le Cirad en partenariat avec un industriel (Cann'elec Développement) et l'INRA.