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Recruitment is a process by which animals can initiate collective movements: the action of an individual prompts conspecifics to follow. Although it has been hypothesized that animals may be able to intentionally recruit others, there is no experimental evidence of this to date. We tested this hypothesis in two pairs of Tonkean macaques in a situation requiring the subjects to find a food site in a 2800 m

[Departement_IRSTEA]Territoires; International audience; Physically and socially heterogeneous mountain landscapes support high biodiversity and multiple ecosystem services. But rapid landscape transformation from fast urbanisation and agricultural intensification around cities to abandonment and depopulation in higher and more remote districts, raises urgent environmental and planning issues. For anticipating their future in a highly uncertain socio-economic context, we engaged stakeholders of a dynamic urban region of the French Alps in an exemplary interactive Participatory Scenario Planning (PSP) for co-creating salient, credible and legitimate scenarios. Stakeholders helped researchers adapt, downscale and spatialize four normative visions from the regional government, co-producing four storylines of trend versus break-away futures. Stakeholder input, combined with planning documents and analyses of recent dynamics, enabled parameterisation of high-resolution models of urban expansion, agriculture and forest dynamics. With similar storylines in spite of stakeholders insisting on different governance arrangements, both trend scenarios met current local and European planning objectives of containing urban expansion and limiting loss and fragmentation of agricultural land. Both break-away scenarios induced considerable conversion from agriculture to forest, but with highly distinctive patterns. Under a commonly investigated, deregulated liberal economic context, encroachment was random and patchy across valleys and mountains. A novel reinforced nature protection scenario affecting primarily mountain and hilly areas fostered deliberate consolidation of forested areas and connectivity. This transdisciplinary approach demonstrated the potential of combining downscaled normative scenarios with local, spatially-precise dynamics informed by stakeholders for local appropriation of top-down visions, and for supporting land planning and subsequent assessment of ecosystem service trade-offs.

The role of ecological science in environmental management has been discussed by many authors who recognize that there is a persistent gap between ecological science and environmental management. Here we develop theory through different perspectives based on knowledge types, research categories and research–management interface types, which we combine into a common framework. To draw out insights for bridging this gap, we build our case by: (i) explicitizing the link between three categories of ecological research and the type of research–management interface they are associated with. We first evaluate three types of unidirectional interfaces and recommend a new kind of interface – called the Research-Within-Management interface (RWM). (ii) suggesting that adaptive management and structured decision-making can integrate all these different angles and serve as meta-interfaces in their relation to research. (iii) distinguishing explanatory knowledge from empirical knowledge, and contending that explanatory knowledge is not necessarily the most important output for the research-management interface today. (iv) highlighting that experiential ecological knowledge—including the expertise and experience of managers, citizens and scientists—is another primary knowledge input in environmental decision-making that should not be systematically downplayed. We point out the complementarities as well as the specificities and limitations of the different types of ecological research, ecological knowledge and research–management interfaces, which is of major importance for environmental management and research policies.

International audience; In many parts of Europe, close-to-nature silviculture (CNS) has been widely advocated as being the best approach for managing forests to cope with future climate change. In this review, we identify and evaluate six principles for enhancing the adaptive capacity of European temperate forests in a changing climate: (1) increase tree species richness, (2) increase structural diversity, (3) maintain and increase genetic variation within tree species, (4) increase resistance of individual trees to biotic and abiotic stress, (5) replace high-risk stands and (6) keep average growing stocks low. We use these principles to examine how three CNS systems (single-tree selection, group selection and shelterwood) serve adaptation strategies. Many attributes of CNS can increase the adaptive capacity of European temperate forests to a changing climate. CNS promotes structural diversity and tree resistance to stressors, and growing stocks can be kept at low levels. However, some deficiencies exist in relation to the adaptation principles of increasing tree species richness, maintaining and increasing genetic variation, and replacing high-risk stands. To address these shortcomings, CNS should make increased use of a range of regeneration methods, in order to promote light-demanding tree species, non-native species and non-local provenances.

The enhancement in durability of Pt nanoparticles modified by nanostructured RuO2 was studied using a model electrode consisting of vacuum deposited Pt on single crystalline RuO2 nanosheets coated on highly oriented pyrolytic graphite (HOPG) surface with sub-monolayer coverage. Atomic force microscopy images showed that Pt on HOPG aggregated and tended to form 3-dimensional islands. On the other hand, Pt formed a well-defined, 2-dimensional over-layer on the RuO2 nanosheet surface. In-situ atomic force microscopy images showed that deposited Pt on the HOPG surface readily dissolved and easily migrated with potential cycling in sulfuric acid, while no such phenomena could be observed on the RuO2 nanosheets. The results indicate that RuO2 nanosheet has a strong affinity toward Pt, namely strong metal-support interaction for Pt, which can be considered as one of the reasons for the enhanced durability of Pt/C modified by RuO2 nanosheets.

A series of composite electrocatalysts composed of RuO2 nanosheets and carbon supported Pt (RuO2ns-Pt/C) has been synthesized by mixing different amounts of commercial 50 wt% Pt/C with RuO2ns derived from exfoliation of layered K0.2RuO2.1 · nH2O. The oxygen reduction activity and stability of the different electrocatalysts has been evaluated as a function of the nanosheet content in the composite electrocatalysts. An increase in initial activity was observed for composite electrocatalyst with RuO2/Pt

Model electrodes consisting of ruthenium oxide nanosheets coated on freshly cleaved highly oriented pyrolytic graphite (RuO2 nanosheet/HOPG) were prepared to investigate the electrostatic interactions between RuO2 nanosheets and electrochemically dissolved Pt ions. The RuO2 nanosheet/HOPG model electrode was dipped into a solution containing dissolved Pt ions generated by potential cycling a Pt working electrode in sulfuric acid electrolyte. Scanning tunneling microscopy revealed preferential adsorption of Pt ions on the nanosheets as island-like deposits, while no such deposits were observed on HOPG. This shows the strong electrostatic interactions between the positively-charged Pt ions and negatively-charged nanosheet. The calculated amount of Pt ions adsorbed was 0.93 × 106 atoms μm−2, which agreed with the theoretical saturated adsorption amount of Pt ion on RuO2 nanosheet of 0.96 × 106 atoms μm−2. All of the Pt ions could be electrochemically reduced to Pt nanoparticles showing activity toward the oxygen reduction reaction. © 2013 The Electrochemical Society. [DOI: 10.1149/2.050403jes] All rights reserved.

The durability of commercial carbon supported Pt nanoparticles with an average particle size of 1.5 nm (20 mass% Pt/C) has been improved by the addition of ruthenium oxide nanosheets (RuO2ns) without sacrificing the initial activity towards oxygen reduction reaction. The initial oxygen reduction reaction activity of the composite catalyst was slightly higher than as-received Pt/C. The electrocatalytic activity after consecutive potential cycling tests of the composite catalyst was c.a. 1.3 times higher than non-modified Pt/C. The increased durability of the composite catalyst is attributed to the improved preservation of the electrochemically active Pt surface area with the addition of ruthenium oxide. Keywords: Polymer electrolyte fuel cell, Oxygen reduction reaction, Durability, Ruthenium oxide, Nanosheets

Composite catalyst (RuO2ns-Pt/C) composed of commercial carbon supported Pt (Pt/C) and various size RuO2 nanosheets (RuO2ns) were synthesized.The improvement in ORR activity and durability of the different catalysts has been evaluated and is discussed as a function of the size of RuO2ns. The RuO2ns size was found to greatly influence the catalytic properties with smaller RuO2ns giving better performance than larger ones. Composite catalyst with small sized RuO2ns exhibit initial activity 2 times higher than Pt/C catalyst and improved activity retention rate.

International audience; Il existe entre forêt et lieux des liens qui pour être explicités font l’objet d’un processus de labellisation. Pour comprendre les liens qui unissent la forêt aux lieux il faut se référer aux travaux qui se sont centrés ces dernières années sur une approche analytique des « ressources territoriales ». Selon cette proposition, les ressources sont créées en réponse aux enjeux de développement (Colletis et Pecqueur 1993, 1995). Cette approche s’appuie sur la distinction entre, d’une part, des ressources qui forment un potentiel à révéler ou à organiser (par exemple un paysage forestier), et d’autre part, les actifs qui sont des facteurs en activité (une filière forêt-bois). Par ailleurs, une seconde distinction oppose d’une part les « ressources génériques », susceptibles d’être transférées (délocalisées) et dont la valeur est indépendante de leur participation au processus de production (par exemple le bois évalué à son cours international), et d’autre part les « ressources spécifiques » dont la valeur résulte explicitement de logiques de différenciation (des essences particulières valorisées en tant que telles, des bois de gros diamètre permettant de faire des produits spécifiques qu’on ne peut pas faire ailleurs). Cette seconde distinction se fonde sur les travaux qui soulignent le lien inextricable entre la ressource et son territoire (Colletis et Pecqueur 2004 ; Gumuchian et Pecqueur 2007).

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International audience; L'objectif de la communication est de montrer le remaniement politique provoqué par l'essor des énergies renouvelables, illustré par le cas du bois-énergie. Le cas du bois-énergie permet de saisir la difficulté de gérer collectivement une ressource à renouvellement lent, renvoyant de plus à de multiples référentiels, forestiers, énergétiques ou territoriaux. Au-delà de l’optimisation technique et logistique, il s'agit de proposer une réflexion politique autour des concepts de bien commun et de justice.

Multifunctional ionomers based on poly(oxyethylene)-co-poly(epichlorohydrin) random copolymers were blended with poly(oxyethylene) or cross-linked through urethane curing. Their conductivities, transference numbers and electrochemical stability were investigated. The cross-linked materials exhibited good mechanical properties. Gelled by liquid organic electrolytes they provided conductivities very close to that of the liquid electrolyte. A thorough comparative investigation of the cationic transference numbers of cross-linked and uncross-linked ionomers was performed. From these data it may be assumed that the cell electrical polarization is enough to induce chain disentanglements, which result in a significant anionic transference number.

International audience; Salts based on oligoether sulfate have been synthesized. Two families of lithium salt were synthesized, mono and disulfate. The results, in term of ionic conductivities, thermal behaviour, viscosity, transference number and electrochemical stability are reported. These salts have sufficient thermal and electrochemical stabilities and, in addition, they have a cationic transference number close to unity. The influence of alkaline cation was evaluated on conductivity and thermal stability measurements.

To assess how brown capuchin monkeys (Cebus apella) delay gratification and maximize payoff, we carried out four experiments in which six subjects could exchange food pieces with a human experimenter. The pieces differed either in quality or quantity. In qualitative exchanges, all subjects gave a piece of food to receive another of higher value. When the difference of value between the rewards to be returned and those expected was higher, subjects performed better. Only two subjects refrained from nibbling the piece of food before returning it. All subjects performed two or three qualitative exchanges in succession to obtain a given reward. In quantitative exchanges, three subjects returned a food item to obtain a bigger one, but two of them nibbled the item before returning it. Individual differences were marked. Subjects had some difficulties when the food to be returned was similar or equal in quality to that expected.

The great cormorant Phalacrocorax carbo is thought to have a wettable plumage, providing low body insulation during foraging. Great cormorants should thus be constrained by water temperatures, and show high energy requirements. Surprisingly, this species has one of the widest breeding distributions of all diving birds, and does not require more food than these other species. We explored this apparent paradox by comparing the insulative properties of body plumage in four subspecies of great cormorants ranging from tropical to polar regions. We found that all subspecies retained an insulating air layer in their plumage, which was, however, much thinner than for other species of diving birds. Detailed examination of the plumage showed that each cormorant body feather has a loose, instantaneously wet, outer section and a highly waterproof central portion. This indicates that the plumage of great cormorants is only partly wettable, and that birds maintain a thin layer of air in their plumage. Our findings suggest an unusual morphological-functional adaptation to diving which balances the antagonist constraints of thermoregulation and buoyancy.

In the French region Rhône-Alpes, the resource is abundant but hardly accessible due to the sharp relief. Thus, developing energy wood is constricted by a series of challenges. The question addressed in this note is how can be built a shared approach, organized by groups from different sectors.At national scale, the compartmentalization of energy and forest policies induces coordination issues for the actors at regional scale. Energy wood is a by-product for these two sectors. Hence, they face issue to coordinate with each other. Accessing information about regional resource availability and consumption are key issues for actors. In the 1980s and the 1990s, local and regional initiatives were progressively structured. Then, in the 2000s, incentives for important boilers and combined heat and power aroused tensions. New configurations resulted from these changes, more or less resistant, to adapt to this new demand. First, demonstrations were made, and then experiences from these demonstrations were discussed in groups. Collectives dedicated to energy wood emerged, based on these groups, with new importance to some actors, like the representatives of the French national agency for environment and energy (ADEME) at local scale, or the energy technology cluster, Tenerrdis, at regional scale, as regional leaders. Indeed, the need for database providing enough information about resource availability and consumption highlighted the importance of these actors. The openness of such database is an important question and so is their aim: help to settle the future national policies, facilitator for local leadership, commercial use for sector actors or prevention to wood smoke pollution? In several other French regions exist different other attempts to provide such database, for instance in the adjacent Auvergne region, but the Rhône-Alpes region gather different observatories, in particular regarding air quality and local leadership.Our work suggests that the different policies related to energy wood face difficulties to converge and set up goals shared by both the energy sector and the forest sector. Observatories and database about resource availability and consumptions represent an important issue to arouse a common intelligence between these different collectives., Dans une région française, Rhône-Alpes, où la ressource est abondante mais difficilement accessible du fait notamment d’un relief marqué, le développement du bois-énergie présente plusieurs défis. La question posée par cette note est celle des modalités de construction d’une démarche commune structurée par des groupes d’acteurs appartenant à des filières différentes.Le cloisonnement à l’échelle nationale des politiques de l’énergie et de la forêt pose en effet des problèmes de coordination au niveau régional pour les différents acteurs. Le bois-énergie demeure un coproduit entre ces deux filières qui, de ce fait, se coordonnent difficilement. L’accès à l’information quant à la ressource disponible en termes d’accessibilité et aux consommations déjà existantes est un enjeu primordial pour les acteurs. La structuration progressive dans les années 1980 et 1990 des initiatives locales puis régionales s’est difficilement accommodée de l’arrivée de projets de très forte puissance dans les années 2000. De nouvelles configurations d’acteurs se sont dessinées, plus ou moins solides, afin de s’adapter à cette nouvelle demande. Passant par des opérations pilotes destinées à servir de démonstrations et de base d’expérience pour les acteurs, discutées ensuite en groupes de travail, ces configurations ont fait émerger de nouveaux collectifs dédiés au bois-énergie. Certains acteurs publics extérieurs aux administrations et agences de l’État ont pris une importance nouvelle au cours de cette période, comme les Espaces info-énergie, ou le pôle de compétitivité Tenerrdis en tant qu’animateurs de la filière. En effet, le besoin de pilotage de bases de données offrant une visibilité sur la ressource et les consommations a permis de mettre en valeur cette catégorie d’acteurs. La question de l’ouverture de ces bases de données se pose activement, ainsi que celle de leur finalité : aide à la préparation de futures politiques nationales, facilitation de l’animation locale, utilisation par les professionnels pour alimenter leurs démarches commerciales, prévention des enjeux de pollutions aux particules fines ? Il existe, dans d’autres régions, différentes tentatives pour porter des outils de connaissance du bois en tant que combustible (en Auvergne par exemple), mais Rhône-Alpes concentre plusieurs observatoires, relevant de plusieurs de ces questions, notamment la question de la qualité de l’air et celle de l’animation locale.Au final, nous montrons que les différentes politiques dont le bois-énergie relève rencontrent des difficultés pour converger et mettre en place des objectifs partagés entre forêt d’un côté et énergie et climat de l’autre. Les observatoires et bases de données sur la ressource et les consommations existantes représentent un enjeu important pour qu’émerge une intelligence commune à ces différents collectifs.

New approaches to forest planning are needed to support the transition of European forests to sustainable management. The aim of this study is to review forest planning systems already in place throughout Europe by exploring a set of case-study countries reflecting the main silvicultural schools of Western Europe, including Belgium, Finland, France, Italy, Portugal, and Slovenia. A literature review and case-study data were used to assess the scale factors (vertical logic) as well as the relationships between forest planning and other environmental6 land-use planning sectors (horizontal logic). The influence of EU policy on the development of forest planning is also discussed. As assessed using the vertical logic, the multi-scale and multi-topic planning approaches adopted in the countries studied here are highly heterogeneous. The horizontal logic shows that despite the importance of an inter-sectoral and harmonic relational framework between forest planning and the planning efforts of other sectors such as landscape and urban planning, the various plans are barely consistent with each other across the European countries studied here. Although interest is growing in the multifunctionality of forests, their sustainable management calls for the development of better integrated planning approaches across Europe.

Spatial heterogeneity and multifunctionality are closely linked concepts: spatial variations in productive potential or in accessibility have lead to diverse uses, which, in turn, will shape diverse environments. Mountain forests have been shaped by centuries of steady use and risk being banalized today because of a rapid decline in the implementation of traditional practices. A policy for a local sustainable development, based on the multifunctionality of forested areas, should, thus, encourage specialization on appropriate sites of limited area to guarantee global multifunctionality on a regional scale.

During the last decade, fuelwood has developed in the alpine territories under voluntarist policies. Facing a next shortage of sawmill by-products, widely used for paper, chipboards and pellets, forest chips are bound to develop for industrial or local use. This is an opportunity for the alpine forests and territories, of which, nevertheless, vulnerability must be taken in account. Studying policies and instruments shows very contrasted approaches, which could generate tensions on the resource, and behaviors in possible contradiction with de development of a true green energy, such as: increase of transport lengths and then of pollutants emissions, degradation of the environment, and loss of the multifunctionality of the forests.

International audience; Depuis dix ans, le bois-énergie se développe dans les territoires alpins, sous l'impulsion de politiques volontaristes. Face à l'épuisement prochain des produits connexes de scierie, déjà largement utilisés dans la papeterie, la panneauterie et la granulation, la plaquette forestière est amenée à se développer pour des usages industriels ou locaux. Il s'agit d'une opportunité pour les territoires et les forêts alpines, dont la vulnérabilité doit cependant être prise en compte dans la délicate conciliation d'objectifs économiques et environnementaux. L'étude des différentes politiques et dispositifs montre des approches très différentes. Cela peut générer des tensions sur la ressource et donner lieux à des comportements contradictoires avec le développement d'une énergie dite verte : allongements des distances de transports et donc des émissions de polluants, dégradation de l'environnement et de la multifonctionnalité des forêts, etc. / During the last decade, fuelwood has developed in the alpine territories under voluntarist policies. Facing a next shortage of sawmill by-products, widely used for paper, chipboards and pellets, forest chips are bound to develop for industrial or local use. This is an opportunity for the alpine forests and territories, of which, nevertheless, vulnerability must be taken in account. Studying policies and instruments shows very contrasted approaches, which could generate tensions on the resource, and behaviors in possible contradiction with de development of a true green energy, such as : increase of transport lengths and then of pollutants emissions, degradation of the environment, and loss of the multifunctionality of the forests.

Decentralisation has given local government additional means to act in respect of forests while assigning a still significant role to the State. The complex system of governance which is taking shape between the various local players and the forestry sector requires proper adaptation of general concepts to local contexts, the development of fora for exchanges and decision-making at various local government levels. The interaction between those levels of thinking and cooperation should build a “learning system” for forests capable of adjudicating the multiple demands placed on forests.

This article focuses on possible developments in silvicultural practices in connection with the projected increased use of timber for energy purposes and higher demand for workable and industrial timber. In the first section, it offers a characterisation of the various types of silvicultural practices. It then discusses possible developments in various silvicultural treatments (forests not under management, occasional treatments, periodic treatments, coppice with standards, coppice, short rotation coppice and very short rotation coppice) under various assumptions: continued present trend, increased logging in the near future under the multifunctional intensification scenario and industrial intensification scenario.

Numerous approaches have been proposed to increase the ORR activity of Pt, including the use of alloys or core-shell structures, oxide additives, graphitized carbon, and others. Although these catalysts have improved activity and/or durability, the preparation scheme for such state-of-the-art catalysts is often multi-process and difficult to produce in large scale. In terms of simplicity of synthesis, the ideal method may be to have a catalyst with high initial activity and durability by making a composite with a commercial Pt/C by a simple one-step process. We have recently reported such a catalyst by mixing ruthenium oxide nanosheets with practical Pt/C [1-7]. Catalysts composed of RuO2 nanosheet and Pt/C (RuO2ns-Pt/C) can be prepared by simply mixing and drying of the two colloids and exhibits higher initial ORR activity and at the same time shows improved performance after accelerated durability cycling tests. However, the reason(s) for the initial activity improvement is poorly understood. For example, the increase (30%) in electrochemically active surface area can only partially explain the initial activity increase. In this study, we focus on the clarifications of the increase in the initial activity of the RuO2ns-Pt/C catalysts with composites prepared with nanosheets having different lateral size by electrochemical impedance spectroscopy and transmission line model simulations. Nanosheets with smaller size resulted in higher activity, which was correlated to a decrease in pore resistance. The initial mass activity of Pt/C is j k=285 A (g-Pt)-1 at 0.85 V vs RHE in 0.5M H2SO4 at 60°C. Addition of 100 nm RuO2 nanosheet improved the initial mass activity to j k=412 A (g-Pt)-1. The impedance spectra were conducted at open charge potential in N2 saturated 0.5M H2SO4 electrolyte at 60°C and simulated with the transmission line model. From the simulation, resistivity in the porous Pt/C was 625 Ω cm-1 whereas with the addition of 100 nm RuO2 nanosheet, resistivity was only 125 Ω cm-1. Addition of nanosheet improved the conductivity in the catalyst layer. The impedance spectra conducted at 0.85V vs RHE in O2 saturated 0.5M H2SO4 electrolyte at 60°C showed that addition of smaller size nanosheet improved the charge transfer reaction of the ORR. This work was supported in part by the “Polymer Electrolyte Fuel Cell Program” from the New Energy and Industrial Technology Development Organization (NEDO), Japan. [1] W. Sugimoto, T. Saida, Y. Takasu, Electrochem. Commun., 8, 411 (2006). [2] T. Saida, W. Sugimoto, Electrochim. Acta, 55, 857 (2010). [3] T. Saida, N. Ogiwara, Y. Takasu, W. Sugimoto, J. Phys. Chem. C, 114, 13390 (2010). [4] D. Takimoto, C. Chauvin, W. Sugimoto, Electrochem. Commun, 33, 123 (2013). [5] Q. Liu, K. S. Lokesh, C. Chauvin, W. Sugimoto, J. Electrochem. Soc., 161(3), F259 (2014). [6] C. Chauvin, T. Saida W. Sugimoto, J. Electrochem. Soc., 161, F318 (2014). [7] Q. Liu, C. Chauvin, W. Sugimoto, J. Electrochem. Soc., 161(3), F360 (2014).

International audience; Polymer electrolytes based on mixtures of lithium trifluoromethylsulfonylimide, LiTFSI and lithium oligoether sulfates dissolved in poly(oxyethylene) were studied. The properties of these mixed electrolytes i.e. thermal stability, ionic conductivities, transference numbers, diffusion coefficients and electrochemical stabilities were established in a wide range of compositions. A satisfactory compromise was found between high cationic transference numbers and high conductivities, while markedly decreasing the total amount of LiTFSI used. Since lithium oligoether sulfates should be considerably less expensive than LiTFSI and easy to recycle, these mixed polymer electrolytes seem to be promising.

International audience; Electrolytes based on lithium oligoether sulfate, and dissolved in liquid or polymer solvents, are studied. Their properties in term of ionic conductivities, transference numbers, diffusion coefficients, and electrochemical stabilities are reported. The comparison between NMR and electrochemical data, that is, transference numbers and conductivities, provides important information about the existence of ion pairs and aggregates. A fairly good agreement can be noticed between the highest occupied molecular orbital (HOMO) energies and the stability of the salts towards oxidation in relation with the length of the oligoether tail.

Delayed reciprocity is a potentially important mechanism for cooperation to occur. It is however rarely reported among animals, possibly because it requires special skills like the ability to plan a loss. We tested six brown capuchin monkeys ( Cebus apella ) in such skills. Subjects were studied in exchange tasks in which they had to retain a food item for a given time lag before returning it to an experimenter and obtaining a more desirable reward. Experiments showed that the subjects could wait for several minutes when allowed to return only part of the initial item. When required to return the full item intact, however, most subjects could not sustain a time lag longer than 10 s. Although the duration of waiting increased with the amount of return expected by subjects, in most cases it did not extend beyond 20 s even when the eperimenter offered a food amount 40 fold the initial item. The failure of capuchin monkeys to sustain long-lasting waiting periods may be explained by limited self-control abilities. This would prevent them achieving reciprocal altruism.

International audience; Suite aux engagements du chapitre 13 de l'Agenda 21 portant sur la gestion des écosystèmes fragiles, divers textes politiques de portée internationale ont été établis dans les années 1990. Cependant, les forêts de montagne, justifiant a priori d'une attention politique particulière, n'ont pas fait l'objet jusqu'à présent de propositions intergouvernementales spécifiques, de critères et indicateurs pour la gestion durable de ces forêts. Cet article présente les résultats d'une analyse qui a porté sur trois textes européens traitant des forêts de montagne : la résolution 54 de la première Conférence ministérielle sur la Protection des Forêts en Europe (CMPFE) de 1990 le protocole Forêts de montagne de la Convention alpine de 1991 ; et le Livre blanc de la Forêt de montagne (2000). Sur la base du Processus d'Helsinki, nous avons identifié à partir de cette analyse un ensemble de critères et indicateurs spécifiques aux forêts de montagne, caractérisant le contexte normatif européen.

International audience; Le programme Life "Méthodes de suivi pour une gestion forestière durable", impliquant l'Allemagne, le Danemark, la Finlande, la France et la Suède, visait à vérifier et à comparer l'adaptation des critères et indicateurs d'Helsinki aux échelles régionales et/ou microrégionales. En France, l'objectif plus particulier des partenaires (Cemagref, IDF, ENGREF, ONF, IFN) était de sélectionner et de tester un ensemble d'indicateurs potentiellement pertinents à l'échelle de la petite région forestière (PRF). Après un inventaire bibliographique, les quatre groupes de travail locaux du projet ont établi un référentiel commun d'une centaine d'indicateurs. Ils les ont hiérarchisés, pour chacune des 4 PRF étudiées, à partir d'un système de cotation spécifique, fondé sur le principe : utilité d'un indicateur = faisabilité x pertinence. De ces listes hiérarchisées, une quinzaine d'indicateurs, choisis parmi les plus pertinents localement, ont été effectivement calculés, principalement à partir des données IFN. Une fiche de présentation adaptée a été mise au point pour faciliter la communication des indicateurs réalisés. L'ensemble de ces démarches a été l'occasion d'échanges de vue approfondis entre les partenaires, les amenant à se dégager des visions tactiques communes à court terme, dans le sens d'une gestion forestière plus concertée à l'échelle d'un petit territoire.

It is possible that non-specialised cues transmitted by conspecifics guide animals' food search provided they have the cognitive abilities needed to read these cues. Macaques often check the mouth of their group-mates by olfactory and/or visual inspection. We investigated whether Tonkean macaques ( Macaca tonkeana) can find the location of distant food on the basis of cues conveyed by group-mates. The subjects of the study were two 6-year-old males, who belonged to a social group of Tonkean macaques raised in semi-free-ranging conditions. In a first experiment, we tested whether the subject can choose between two sites after having sniffed a partner who has just eaten food corresponding to one of the sites. We found that both subjects were able to choose the matching site significantly above the chance level. This demonstrated that Tonkean macaques are capable of delayed olfactory matching. They could associate a food location with an odour conveyed by a partner. In a second experiment, the same subjects were allowed to see their partner through a Plexiglas window. Both subjects were still able to choose the matching site, demonstrating they could rely on visual cues alone. Passive recruitment of partners appears possible in macaques. They can improve their foraging performances by finding the location of environmental resources from olfactory or visual cues conveyed by group-mates.

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The erosion protection division of Cemagref at Grenoble has perfected a method of ranking forests in terms of their role as a protection from avalanches. This is based on risk analysis carried out by the R.T.M. services of the O.N.F. This method takes into account the importance of natural hazards (avalanches, rock falls, etc.), the structure and dendrometric parameters of the forest cover and the vulnerability of the threatened sites. It also provides the criteria by which to determine those afforested areas from which avalanches are likely to start. A statistical model to calculate the stopping distance, developed by the Norvegians and adapted to French topographical conditions by Cemagref at Grenoble, is used to determine the probable stopping zones of these phenomena. All these criteria have enabled the completion of a Map of the Probable Location of Avalanches, based exclusively on observed events. The comparison of such information with forest data shows that forest maintain these phenomena at a level of potential activity. However, understanding of the control of this hazard by the forest requires a better comprehension of the interactions between forests and snow, and forest and the snow mantle. To do this, an experimental study plan of snow in forests has been made., La division protection contre les érosions du Cemagref de Grenoble a mis au point une méthode de hiérarchisation des forêts à rôle de protection dérivée des analyses "enjeux- risques" des services Restauration des terrains en montagne (R.T.M.) de l'Office National des Forêts (O.N.F.). Cette méthode prend en compte la nature et l'importance des aléas naturels (avalanches, chute de blocs, etc.), la structure et les paramètres dendrométriques des peuplements et la vulnérabilité des enjeux menacés. Elle permet aussi de donner des critères de détermination des zones de départ potentiel d'avalanche sous couvert forestier. Un modèle statistique de calcul des distances d'arrêt, développé par les norvégiens et adapté aux conditions topographiques françaises par la division nivologie du Cemagref de Grenoble, est utilisé pour déterminer les zones d'arrêt probable de ces phénomènes. L'ensemble de ces critères permet de compléter la carte de localisation probable des avalanches (CL. P. A.), qui ne recense que les phénomènes déclarés. Le croisement de ces informations avec les données forestières met en évidence que les forêts maintiennent ces phénomènes à un niveau d'activité potentielle. Mais la compréhension de cette maîtrise de l'aléa par la forêt nécessite une meilleure compréhension des interactions forêt/neige et forêt/manteau neigeux. Pour ce faire, un dispositif expérimental d'étude de la neige en forêt a été réalisé., Berger Frédéric, Chauvin Christophe. Cartographie des fonctions de protection de la forêt de montagne : appréciation des potentialités d'avalanche sous couvert forestier / Mapping the protective roles of mountain forests : assessing avalanche potentials in forested areas. In: Revue de géographie de Lyon, vol. 71, n°2, 1996. Système d'information géographique et gestion de l'environnement. pp. 137-145.

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Les forets de montagne sont soumises a de nombreuses contraintes allant de la complexite du milieu a la diversite des usages et jusqu'aux difficultes rencontrees dans le passe pour leur amenagement. C'est pourquoi les decisions de gestion doivent s'appuyer en particulier sur une analyse precise des peuplements, dans l'esprit de la methode du controle, s'inscrivant dans le mode de pensee et d'action du sylviculteur qui aura a realiser, suivre et controler les interventions preconisees. C'est aussi pourquoi l'amenagement doit etre l'occasion d'une concertation entre les differents usagers, qui sera facilitee par l'utilisation des possibilites de la cartographie (objectifs, fonctions, desserte) et de l'analyse multicritere.

A l’echelle des Alpes francaises existe toutefois une tendance generale a la destabilisation d’un certain nombre de peuplements forestiers de montagne, notamment pessieres, ayant subi la meme sequence de traitements contradictoires : surexploitation jusqu’au milieu du XIXe siecle, puis forte protection et, depuis quelques decennies, risque d’abandon pour des raisons economiques. Ces peuplements tres homogenes et elances, souvent surannes, representent maintenant d’importantes surfaces fragilisees.

Une methode de determination et de cartographie de Zones d’interventions forestieres prioritaires (ZIFP) a ete developpee par F. Berger dans le departement de la Savoie (Alpes du Nord) (Berger et Renaud, 1994 ; Berger, 1994, 1997). Cette methode, qui repose en partie sur l’utilisation du Systeme d’information geographique (SIG) ARC/INFO, constitue un outil d’aide a la decision et a la gestion minimale des forets de montagne a role de protection : elle permet d’orienter l’utilisation des credits mis a disposition des gestionnaires forestiers pour assurer la perennite de la fonction de protection des forets.