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N° ISBN - 978-2-7380-1284-5 ; International audience ; This paper aim to analyze the consequences of the creation of firewood rural markets in Niger. We made an assessment of the changes of interactions between ecosystem services linked with the creation of rural market. The study was based on interviews conducted at the local scale of the rural market of Ñinpelima in order to assess the changes between 1980 and 2009. We define ecosystem services as an interaction between a social system and an ecological system. This definition allows us to characterize ecosystem services and the origins of their interactions. The synergies and trade-offs observed are the results of two types of interactions between ecosystem services: cooperation and competition. Rural markets rely on institutional and technical innovation at the national scale. These innovations affect the local scale. Although the creation of rural market aims essentially the service of firewood production, the interactions lead to changes of other ecosystem services. Management strategies have to take in account these interactions for that rural markets of firewood achieve their objective of sustainable management of the ecosystems as a whole.

N° ISBN - 978-2-7380-1284-5 ; International audience ; This paper aim to analyze the consequences of the creation of firewood rural markets in Niger. We made an assessment of the changes of interactions between ecosystem services linked with the creation of rural market. The study was based on interviews conducted at the local scale of the rural market of Ñinpelima in order to assess the changes between 1980 and 2009. We define ecosystem services as an interaction between a social system and an ecological system. This definition allows us to characterize ecosystem services and the origins of their interactions. The synergies and trade-offs observed are the results of two types of interactions between ecosystem services: cooperation and competition. Rural markets rely on institutional and technical innovation at the national scale. These innovations affect the local scale. Although the creation of rural market aims essentially the service of firewood production, the interactions lead to changes of other ecosystem services. Management strategies have to take in account these interactions for that rural markets of firewood achieve their objective of sustainable management of the ecosystems as a whole.

Background: Chemical soil factors play an important role in generating and maintaining plant diversity. Naturally metal-enriched habitats support highly distinctive plant communities consisting of many rare and endemic species. Species of these plant communities possess remarkable physiological adaptations and are now being considered key elements in the implementation of green technologies aimed at phytoremediation of contaminated soils and post-mined soils. Several studies have emphasised that industrial mineral extraction results in serious damage to ecosystems and serious threats to human health and leads to the extinction of metallophyte species. In the southeastern Democratic Republic of the Congo (DRC), mining activities represent a threat to the long-term persistence of communities located on metalliferous copper and cobalt outcrops and their associated endemic metallophytes, which are currently considered some of the most critically endangered plants in the world. Scope: Plant diversity conservation of metal-rich soils must assess soil-plant relationships at different scales (ecosystems, communities, and populations) to define in-situ and ex-situ conservation and restoration projects. This paper proposes a review of soil-plant relationships involved in plant diversity and endemism and their implications for biodiversity conservation and restoration. ; SCOPUS: ar.j ; info:eu-repo/semantics/published

Developments in the international institutional context and in the capacity of governments to ensure sustainable forest management in Central Africa lead to new approaches to participatory management being explored. The author reviews current initiatives in this field in Congo Brazzaville, Gabon, Cameroon, Central African Republic and Equatorial Guinea. Such initiatives are still in an experimental stage and aim at answering issues linked with conventional forest management as well as meeting prerequisites imposed by international organisations for granting aid to development. These new approaches apply to four main areas: (1) Planning in the form of Forest Action Plans (TFAP/NFAP) and Environmental Management or Action Plans (EMP/EAP). Only those being in a development process take into account the participatory approach. (2) Protected areas. The current trend, especially at regional level (ECOFAC), is to substitute involvement of local populations in sustainable resource management for protection of forest islands. (3) Community forests. Cameroon has changed its legislation and is in an experimental stage. Congo and Gabon are engaged in reforming their laws. And (4) Management for timber production. Participation of local people is recommended, however the mode of implementation is not clearly defined. Research is involved at different levels: function of advice and analysis, definition of operational modes of implementation, and social experimentation. The author describes analysis patterns (theory of land control, modes of appropriation), and the main research focuses. Most important is communication, using approaches such as GRAAP (Research Group in Support to Self-Promotion) and MARP (Active Method of Participatory Research). Objectives are listening, informing and awareness-raising. The economic alternatives approach, based on a combination of incentives and disincentives, is increasingly used, as well as institutional alternatives approach. The success of a co-management process is dependent on taking into account all categories of actors involved in decision-making.

Biodiversity is one of the global issues that explicitly responds to the notion of sustainable development. It is an explicit concern for human needs, for which it constitutes living natural resources found in nature. The fundamental concept of biodiversity is introduced by studying the spatial distribution of species and, more specifically, the well-known Species Area Relationship (SAR). Knowing the zone-species law that truly manages the phenomenon of spatial distribution of species enables us to predict the response of biodiversity to environmental changes at different scales and to assess policy options for global biodiversity conservation. Indeed, within the framework of this thesis, we propose a new approach to the phenomenon of spatial distribution of species and individuals by using the same tools and physical properties that the ones commonly used to treat statistical and geometrical dynamics of developed turbulence. For this purpose, we have adopted the dynamics of entropic skins E.S. describing the intermittence phenomenon in turbulence. The P.E. model was applied to experimental data on the spatial distribution of species through a geometry simulating the distribution of individuals in a form close to the two-dimensional Cantor geometry. We found that the distributions of species and individuals are well described by the E.S. model. Both spatial distributions show intermittent dynamics with a hierarchy of entropic skins extending between a parabolic fractal body (corresponding to the spatial extension of the less ordered plant population) and a pure fractal crest (corresponding to the metabolically active and ordered areas). Intermittence statistics can thus occur in phenomena other than turbulence. ; La biodiversité est un des enjeux internationaux qui répond explicitement à la notion du développement durable. C'est un intérêt explicite pour les besoins humains qui constitue des ressources naturelles vivantes se trouvant dans la nature. La biodiversité dans son concept fondamental est introduite par l'étude de la distribution spatiale des espèces et plus précisément la relation bien connue zone-espèces (Species Area Relationship ; SAR). La connaissance de la loi zones-espèces qui gère véritablement le phénomène de distribution spatiale des espèces nous permet de prédire la réponse de la biodiversité aux changements environnementaux à différentes échelles et d'évaluer les options politiques de conservation globale de la biodiversité. En effet, dans le cadre de cette thèse, nous proposons une nouvelle approche du phénomène de distribution spatiale des espèces et des individus en utilisant les mêmes outils et propriétés physiques que pour traiter la dynamique statistique et géométrique caractérisant le phénomène de turbulence développée. Dans ce sens, nous avons adopté la dynamique de peaux entropiques P.E décrivant le phénomène d'intermittence en turbulence. ce modèle a été appliqué sur des données expérimentales de distributions spatiales d'espèces en utilisant une géométrie simulant la distribution des individus sous une forme se rapprochant de la géométrie du Cantor à deux dimensions. Les résultats montrent que la répartition des espèces et des individus est bien décrite par le modèle des P.E. Ces deux distributions spatiales montrent une dynamique intermittente possédant une hiérarchie de peaux entropiques qui s'étend entre, un corps fractal parabolique et une crête fractale pure. On voit ainsi que les statistiques d'intermittence peuvent se produire dans des phénomènes autres que la turbulence.

The aim of this thesis was to document, at regional scale (SW France), the application of litter decomposition and associated metrics as a proxy of functional integrity of stream ecosystems. The Introduction exposed the underlying arguments, mainly relying on (1) the importance of this ecosystem process, which provides most carbon sources to the aquatic food web, and (2) the need to complement the structural metrics routinely used in biomonitoring schemes by a functional component. Chapter I dealt with the capacity, by using litter decomposition, to discriminate the effects of pesticides from other stressors in 12 agricultural streams selected along a contamination gradient. The decomposition rate was twice as low in the most contaminated site compared with the less contaminated one, and the relationship was monotonous along the gradient. Only the activity of invertebrate decomposers was affected, translating into the switch from a decomposition co-dominated by invertebrates and microorganisms in the less contaminated sites to a process only achieved by microorganisms in the most contaminated ones. Taxonomic richness and density of invertebrate decomposers together with a specific indicator based on invertebrate traits followed the same trends as the invertebrate-driven decomposition rate, kinvertebrate, while fungal biomass, sporulation rate and taxonomic richness remained unaffected. Consequently, the presence of pesticides compromised leaf breakdown, as microbial decomposers did not compensate for the invertebrate decomposers decline. This occurred while pesticides concentrations even in the most contaminated stream were under the European Union's Uniform Principles thresholds for targeted species. This study showed that litter breakdown, particularly the ratio of total to microbial-driven breakdown rate, is a pertinent proxy to assess the functional integrity of pesticide-contaminated streams. Chapter II compared the biological evaluation, as routinely undertaken in monitoring schemes from structural ...

The aim of this thesis was to document, at regional scale (SW France), the application of litter decomposition and associated metrics as a proxy of functional integrity of stream ecosystems. The Introduction exposed the underlying arguments, mainly relying on (1) the importance of this ecosystem process, which provides most carbon sources to the aquatic food web, and (2) the need to complement the structural metrics routinely used in biomonitoring schemes by a functional component. Chapter I dealt with the capacity, by using litter decomposition, to discriminate the effects of pesticides from other stressors in 12 agricultural streams selected along a contamination gradient. The decomposition rate was twice as low in the most contaminated site compared with the less contaminated one, and the relationship was monotonous along the gradient. Only the activity of invertebrate decomposers was affected, translating into the switch from a decomposition co-dominated by invertebrates and microorganisms in the less contaminated sites to a process only achieved by microorganisms in the most contaminated ones. Taxonomic richness and density of invertebrate decomposers together with a specific indicator based on invertebrate traits followed the same trends as the invertebrate-driven decomposition rate, kinvertebrate, while fungal biomass, sporulation rate and taxonomic richness remained unaffected. Consequently, the presence of pesticides compromised leaf breakdown, as microbial decomposers did not compensate for the invertebrate decomposers decline. This occurred while pesticides concentrations even in the most contaminated stream were under the European Union's Uniform Principles thresholds for targeted species. This study showed that litter breakdown, particularly the ratio of total to microbial-driven breakdown rate, is a pertinent proxy to assess the functional integrity of pesticide-contaminated streams. Chapter II compared the biological evaluation, as routinely undertaken in monitoring schemes from structural ...

The aim of this thesis was to document, at regional scale (SW France), the application of litter decomposition and associated metrics as a proxy of functional integrity of stream ecosystems. The Introduction exposed the underlying arguments, mainly relying on (1) the importance of this ecosystem process, which provides most carbon sources to the aquatic food web, and (2) the need to complement the structural metrics routinely used in biomonitoring schemes by a functional component. Chapter I dealt with the capacity, by using litter decomposition, to discriminate the effects of pesticides from other stressors in 12 agricultural streams selected along a contamination gradient. The decomposition rate was twice as low in the most contaminated site compared with the less contaminated one, and the relationship was monotonous along the gradient. Only the activity of invertebrate decomposers was affected, translating into the switch from a decomposition co-dominated by invertebrates and microorganisms in the less contaminated sites to a process only achieved by microorganisms in the most contaminated ones. Taxonomic richness and density of invertebrate decomposers together with a specific indicator based on invertebrate traits followed the same trends as the invertebrate-driven decomposition rate, kinvertebrate, while fungal biomass, sporulation rate and taxonomic richness remained unaffected. Consequently, the presence of pesticides compromised leaf breakdown, as microbial decomposers did not compensate for the invertebrate decomposers decline. This occurred while pesticides concentrations even in the most contaminated stream were under the European Union's Uniform Principles thresholds for targeted species. This study showed that litter breakdown, particularly the ratio of total to microbial-driven breakdown rate, is a pertinent proxy to assess the functional integrity of pesticide-contaminated streams. Chapter II compared the biological evaluation, as routinely undertaken in monitoring schemes from structural ...

While one of the major objectives put forward by the IPBES (2019) is to feed the planet while improving the overall health of ecosystems, intensive agriculture remains one of the main causes of biodiversity decline, of which the decline of pollinators on a global scale is emblematic. Pollinated crops represent nearly 80% of the species grown in Europe and play a crucial ecological and economic role in agro-ecosystems (Klein et al., 2007). Therefore, the decline of pollinators questions current agricultural practices. The objective of this thesis is to identify and evaluate effective and sustainable solutions to ensure the provision of the pollination service in intensive agroecosystems. To date, research conducted to tackle pollinator decline has focused on several technical responses, while ignoring the preferences of farmers or beekeepers. First, we identify the most effective technical levers to increase the magnitude of the pollination service, and then analyze agents' preferences about them. In a second step, we evaluate some bioeconomic responses (i.e. combining the adoption of a practice with a socio-economic motivation) from an economic but also an ecological point of view. To do so, we use concepts and theories from several academic fields, mainly from economics and psychology, as well as bioeconomic modeling and econometric approaches. We focus on the case study of the "Plaine & Val de Sèvre" area (Deux-Sèvres, France), a typical West European intensive agroecosystem, which we use for model calibration. For the identification of preferences, we use two datasets from farmer surveys: one conducted in the Deux-Sèvres area, and one conducted online at the national level. Our results show that the pro-pollinator practices have a high acceptability among farmers, but that they are not widely adopted. The most effective levers are often the least adopted. We show that adoption is influenced by costs, but also by risk preferences and other behavioral factors. We first simulate, using a bioeconomic model, a ...

Ecosystems provide several benefits essential to human well-being, called ecosystem services (ES). In some cases, these ES may present trade-offs (provision of one ES increases while another decreases) or synergies (two or more ES change in the same direction). Analyzing and quantifying these relationships (trade-offs or synergies) at the ecosystem level remains a major scientific challenge fortheir sustainable management. In this thesis, we analyzed and quantified in arable ecosystems of mainland France, the relationships between different ES and goods related to soil functioning : the agricultural production, two services to farmers – nitrogen provision to crops and water provision to crops – and three services to society– blue water provision, water quality regulation, and climate regulation via the carbon sequestration in soils. In general, our results contribute to improving current knowledge on the relationships between ES in arable ecosystems and the strategies of their management. ; Les écosystèmes fournissent de nombreux bénéfices essentiels au bien-être humain, dénommés services écosystémiques (SE). Dans certains cas, ces SE peuvent présenter des antagonismes (augmentation d'un SE et diminution d'un autre) ou des synergies (deux SE ou plus varient dans le même sens). Analyser et quantifier ses relations (antagonismes ou synergies) à l'échelle des écosystèmes demeure un défi scientifique majeur pour leur gestion durable. Dans cette thèse, nous avons analysé et quantifié à l'échelle des écosystèmes cultivés de la France métropolitaine, les relations entre différents SE et biens liés au fonctionnement du sol : la production agricole (biens végétaux), deux services rendus à l'agriculteur – fourniture en azote et en eau verte aux plantes cultivées – et trois services rendus à la société – stockage et restitution de l'eau bleue, régulation de la qualité de l'eau et régulation du climat global via le stockage du carbone dans le sol. En général, nos résultats contribuent à améliorer les connaissances actuelles ...

La prise de conscience, par le grand public, de l'impact grandissant de l'homme sur l'océan est récente. Elle se traduit par une volonté politique sincère de correction par des mesures de protection, de gestion et de développement durable. Ces politiques, et leurs conséquences économiques et sociétales lourdes, ne peuvent être acceptées que si les décisions se fondent sur des connaissances scientifiques incontestables et montrent des résultats scientifiquement prouvés. Par ailleurs, ces décisions doivent prendre en compte des impacts qui s'opèrent à des échelles de temps et d'espace très variables, de quelques heures à plusieurs dizaines d'années et de quelques mètres à plusieurs milliers de km. En termes politiques, l'information scientifique nécessaire à la prise de décision doit pouvoir couvrir les différentes échelles depuis le niveau local et régional, jusqu'à l'échelle nationale, européenne voire globale, et cela sur le plus long terme possible. Enfin, pour être complète, l'information scientifique sur les écosystèmes marins doit pouvoir répondre à trois questions objectives : (i) quel est l'état? (ii) quelle est l'évolution? (iii) quels sont les mécanismes et processus mis en jeux? et à une question plus prospective : (vi) que peux-t-on prévoir et comment agir? Le présent rapport ne peut pas, à lui seul, refléter toute la richesse du programme STARECAPMED. En 3 ans, STARECAPMED a généré plusieurs centaines de milliers de données nouvelles, ré-exploité plusieurs centaines de publications, rapports et autres enregistrements passés et présents. Le programme a aussi généré de nombreux documents, rapports et mémoires. Enfin, des publications internationales et des thèses de doctorat sont en cours de réalisation ou abouties. Afin de rester lisible, nous avons donc choisi de présenter ce rapport 2014 sous la forme de 12 exemples parmi les travaux en cours. Ces exemples sont traités selon un schéma identique en 4 points simples : (i) La présentation du cas d'étude dans le projet global ; (ii),Les approches innovatrices développées ; (iii),La présentation de résultats marquants ; (iv),Les délivrables de STARECAPMED pour les politiques publiques.