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In Niger, literature from the years 1990–2020 shows a rapid regression in the surface areas of forest, an abundant regeneration of trees in some cultivated areas, and a sharp increase in the consumption of wood energy in cities and the countryside, with this wood increasingly coming from parklands. This study, carried out in 2015–2019 on the outskirts of Niamey, aimed to assess the economic benefits for households of parkland fuelwood production and the ecological state of the parklands. Surveys were carried out among 90 farmers to assess the contribution of fuelwood to their household income. Semi-structured interviews with focus groups were conducted in 3 villages to determine farmers' strategies and practices. The inventory of the trees in the parklands was carried out in 3 villages (5000 ha per village). Most rural households have an income diversification strategy to cope with the vagaries of agricultural production. Among these revenues, the sale of fuelwood occupies on average a small place (4 to 10%). To explain their reduced use of assisted natural regeneration (ANR) for the restoration of parklands, farmers point to the difficulty in exploiting wood pruned from their trees due to conflicts of use with livestock herders, taxes and fines from environmental services agencies. Trees and shrubs in parklands have a low diversity (24 species) and low density (5–8 trees/ha). The low density of young trees indicates that during the past decade, there have been fewer efforts to enrich parklands compared to the 1980s, when ANR projects were first implemented. The 3 parklands studied are in the process of becoming severely degraded because dead old trees are no longer replaced through ANR. The Economic importance of fuelwod in family resources is not a sufficient trigger factor for farmers to restore their parklands but could support village's interest for sustainable management of natural forests. These results should serve to alert public authorities and aid organizations that research and development actions must be launched to reverse this deterioration trend in parklands.

In West Africa, household energy transition has so far mainly been synonymous with the conversion from woodfuel to LPG. This paper analyses the failure of 30 years of household energy transition policies in Mali by combining two major frameworks: Multi-Level Perspective (MLP) and Social Practice Theory (SPT). Based on empirical field studies undertaken in Bamako since 1985 and on literature review, two historical narratives are presented, one focusing on the dynamics of the dominant woodfuel regime and the other on changes in cooking practices. The MLP analysis showed that all elements seemed aligned for destabilization of the dominant regime, yet the woodfuel regime has resisted and is maintained. The SPT analysis showed that the stability of cooking, eating and fuel purchasing practices did not converge towards and even opposed the transition to LPG. This paper shows that the MLP and SPT frameworks offer complementary perspectives for understanding transitions in developing countries. It concludes that the definition and implementation of energy policies need to integrate an analysis of daily practices and should consider that energy transition is not synonymous with the replacement of one fuel by another, but with new opportunities to diversify ways of cooking.

Over 90% of the rural population in sub-Saharan Africa still relies on fuelwood as their primary source of household energy. In this context, recent robust data on fuelwood consumption in rural areas are needed to conceive and implement appropriate energy policies. This paper identifies the factors that determine fuelwood consumption variability in two villages in Burkina Faso, based on a two-year survey of 60 rural households of different size and wealth status. The women who made up the panel were surveyed at five-day intervals over a period of three months in the rainy season, one month in the cold dry season and one month in the hot dry season. Our results corroborate some fuelwood consumption patterns in rural SSA: fuelwood consumption per adult equivalent decreases both with the size of the household and with local wood scarcity. Conversely, it challenges the idea that the level of consumption is correlated with the level of household wealth. Finally, the most important result is that the scarcity of wood resources leads people to buy fuelwood from outside and adopt strategies to reduce their consumption by reducing the number of cooking cycles and certainly by wasting less energy, whatever the level of household wealth.

Optimal use of resources in agroforestry requires the evaluation of multi-species and multi-strata cropping systems. The current study evaluated the effect of plant diversity on the performance of agroforestry systems in Talamanca, Costa Rica. Plants in nine 100-m2 plots in each of 20 fields were classified into five groups (banana, cacao, other fruits, timber, and firewood), and diversity was assessed by the Shannon–Wiener index. The production of each individual plant was estimated and converted into income according to local market prices. Our results indicated that as plant diversity increased, the income derived per plant increased for other fruits, firewood, and timber and also when all cultivated plants were considered as one group. In contrast, the income derived per plant decreased for banana and cacao as diversity increased. This suggests that complementarity between plants was stronger than competition for those plants occupying the higher strata of the canopy (i.e., other fruits, firewood, and timber) but that competition was stronger than complementarity for plants occupying the lower strata of the canopy (i.e., banana and cacao). These results increase our understanding of how the composition and the organisation of these agroforestry systems may be optimized.

Dans le contexte du changement climatique et de la pauvreté, les populations rurales sont de plus en plus confrontées aux défis de la gestion adéquate des ressources, de la production alimentaire et de l’amélioration de la qualité de vie. Le Guatemala doit faire face au changement climatique et à la pauvreté tout en tenant compte de sa production agricole. À cet égard, les systèmes agroforestiers ont été proposés comme méthode alternative de production durable. Cet article présente une comparaison entre les systèmes agricoles conventionnels et les systèmes agroforestiers enrichis de Camotán et Jocotán. Les résultats montrent que le système agroforestier enrichi contribue à 65 % du bois-énergie contre 7 % pour le système conventionnel. Les familles utilisant le système agricole conventionnel ont extrait 81 % de leur bois-énergie de la forêt, alors que les familles utilisant le système agroforestier enrichi n’en ont extrait que 32 %. Le bois-énergie produit par le système agroforestier enrichi offre un avantage supplémentaire aux femmes, aux enfants et aux jeunes, qui sont chargés de transporter les fagots, car ils n’ont pas à parcourir de longues distances pour approvisionner le foyer. Les familles ont construit et adapté des connaissances empiriques sur la gestion des arbres dans leurs systèmes de culture. Le système agroforestier enrichi est donc présenté comme une solution potentielle pour répondre à la demande annuelle de bois-énergie. La sécurité foncière influence la décision des familles rurales d’investir ou d’innover. Les systèmes agroforestiers jouent un rôle clef dans l’augmentation des ressources et l’amélioration de la qualité de vie.

En République démocratique du Congo, l’agriculture itinérante sur brulis et la production de bois-énergie sont les principales activités génératrices de revenus des populations périurbaines. Mais ces activités sont également les premières causes de déforestation, comme c’est le cas dans un rayon de 200 km autour de Kinshasa et autour des principales métropoles du pays. Afin d’améliorer la gestion des espaces périurbains et d’assurer l’alimentation durable en bois-énergie de Kinshasa, le projet UE Makala a co-construit avec douze communautés du plateau Batéké et du Kongo central des Plans simples de gestion des terroirs et du bois-énergie via une méthode participative. En complément, des itinéraires techniques (plantations agroforestières à Acacia auriculiformis et d’essences locales, régénération naturelle assistée) ont été proposés et testés avec les agriculteurs producteurs de bois-énergie de ces communautés. Après une période de 18 mois de mise en œuvre autonome des Plans simples de gestion, une évaluation de leur appropriation par Principes, critères, indicateurs et vérificateurs a été menée. Cette évaluation a montré que le niveau d’appropriation des Plans simples de gestion et des itinéraires techniques promus par le projet UE Makala est meilleur au Kongo central, où la forêt a quasiment disparu, qu’au plateau Batéké où des reliquats de forêts-galeries existent encore. De plus, il a été mis en évidence dans les deux zones que les activités collectives étaient peu appropriées alors que les activités individuelles, pour lesquelles la répartition du travail et des bénéfices était sans ambiguïtés, ont été plus largement appropriées. Cependant, à l’échelle individuelle, des différences notables d’appropriation ont été constatées en fonction du statut foncier des bénéficiaires. Les faibles superficies disponibles et l’accès au foncier sont les principaux facteurs limitant l’appropriation des itinéraires techniques agroforestiers.

Le charbon de bois restera une source d’énergie importante en Afrique subsaharienne dans un avenir prévisible, le présent article se concentre sur l’amélioration de l’efficacité de la carbonisation comme contribution à des chaînes de valeur plus durables du charbon de bois. Alors que l’efficacité de la conversion du bois en charbon est souvent considérée comme une question technique de performance des fours, cette étude vise à mettre en lumière le rôle d’un contexte institutionnel favorable et les capacités des acteurs impliqués. Sont d’abord passées en revue les initiatives visant à améliorer la production de charbon de bois dans différents pays d’Afrique subsaharienne. Nous comparons ensuite les données sur les processus de carbonisation dans deux zones en République démocratique du Congo : Yangambi et le Plateau de Bateke. Les principales conclusions sont les suivantes : 1) l’amélioration des techniques de carbonisation permet de réaliser d’importants gains en termes de taux de conversion du bois en charbon, mais le succès dépend en grande partie de l’adéquation des solutions de four en fonction du contexte, de la capacité et de la sensibilisation des producteurs et du contexte institutionnel favorable ; 2) le renforcement des capacités des opérateurs et des autres parties prenantes nécessite des techniques de four efficaces, mais aussi une sensibilisation accrue aux avantages et aux options d’approvisionnement durable, le renforcement des compétences financières et de gestion des organisations de producteurs et l’amélioration du transport, de la manutention et de la commercialisation ; 3) le statut illégal ou informel des producteurs de charbon de bois en Afrique subsaharienne nuit à l’efficacité des processus de production du charbon, tandis qu’un cadre institutionnel adéquat facilite l’accès des producteurs aux permis et au financement, fournit une fiscalité claire avec des incitations pour des pratiques plus durables et relie les exigences techniques en termes de carbonisation aux sources et utilisations finales durables. Le succès ou l’échec des techniques de carbonisation améliorées et les résultats socio-écologiques connexes sont déterminés conjointement par les solutions qui incluent les aspects de renforcement des capacités, d’acceptabilité et d’institutions favorables identifiés dans cet article. La poursuite du développement de ces solutions en partenariat avec les producteurs accroît le potentiel de chaînes de valeur plus durables pour le bois-énergie.

We compute the optimal subsidy level for fuelwood consumption that makes it possible to achieve the French biomass energy consumption target. For this purpose, we model the competition and trade-offs between the consumption of fuelwood for heat (FW-H) and the consumption of fuelwood for electricity (FW-E). To do so, we couple a forest sector model with an electricity simulation model, and we test different scenarios combining FW-H and FW-E that account for contrasting potential increases in the carbon price and the potential reduction in the number of nuclear plants. We assess the implications of these scenarios on (1) the budgetary costs for the government, (2) industrial wood producers' profits, (3) cost savings in the power sector for the different scenarios tested, and (4) the carbon balance. We show that the scenario with the highest carbon price and the lowest number of nuclear plants is the least expensive from a budgetary perspective. Indeed, when associated with a high carbon price, co-firing may increase FW-E demand with a lower subsidy level, which makes it possible to reduce the cost of reaching the target. However, in this case, FW-E crowds out part of FW-H, which may cause political and economic issues. From a carbon balance perspective, an FW-H-only scenario performs better than any other scenario that combines FW-H and FW-E due to the relatively low emissions factors of alternative technologies for electricity generation and, in particular, nuclear energy.

Despite its inclusion in the forest laws and the support of the international community, Multiple-use Forest Management (MFM) remains poorly implemented in tropical forests. Two specific barriers limit the effectiveness of this approach in the timber concessions of Central Africa. On one hand, formal attempts at MFM are poorly conceived either because they promote forest uses, such as ecological functions or tourism, that have little relevance to direct stakeholders, or because they rely on the legal definition of local users' rights, which is disconnected to customary rules and practices. The article develops an alternative approach for six timber concessions in Cameroon, Gabon and the Democratic Republic of Congo, in which the foremost purpose of MFM is to solve or reduce actual conflicts of uses, notably regarding agriculture, hunting, chainsaw milling and firewood collection. On the other hand, the costs of implementing MFM measures are rarely estimated and assigned to concerned actors. The costs of resolving conflicts of use were evaluated in the same concessions, based on consensual solutions elaborated by the logging companies, the forestry and agriculture administrations and the local people. In half of these concessions, the cost of MFM equals or exceeds 1.5 million dollars in the next fifteen years. Several trade-offs are possible between these stakeholders, combining tax relief, technical and financial support to local development, and reduction of some illegal practices.

Background In Sub-Saharan Africa (SSA), the production and use of woodfuel remains an important socio-economic activity with more than 70% of the population relying on woodfuel as their primary household energy source. Despite their socio-economic significance, woodfuel value chains are often viewed negatively due to their association with detrimental health and environmental impacts. However, the lack of sound evidence and limited understanding of the role of contextual factors in influencing the various impacts of woodfuel value chains have prevented the formulation of properly guided policy interventions. Thus the objective of this systematic map is to provide a comprehensive review of the environmental, socio-economic, and health impacts of woodfuel value chains across SSA. Methods The search strategy for this review map was defined in a peer-reviewed protocol and refined by iterative testing. Search strings were composed of population, intervention, and location terms and combined using Boolean operators. The bibliographic databases Web of Science, Scopus, and CAB Abstracts were used as the main sources of literature for this review, and a total of 4728 results were initially retrieved. Following title and abstract screening, 659 entered full text screening. Critical appraisal of 219 articles led to the exclusion of studies that did not set meet quality criteria for this map, resulting in a final total of 131 articles for inclusion in data extraction and analysis. Results From the 131 included articles, 152 individual studies were identified during data extraction. Studies came from 26 of the 49 Sub Saharan African countries, with a particular preponderance of articles published in the last 10 years. Critical appraisal found significant weaknesses in the experimental design of woodfuel value chain studies with the exception of health impact studies, which frequently utilized controls or other relevant comparators. Findings suggest that woodfuel value chains have environmental, socioeconomic and health consequences with the frequent presence of trade-offs. The reporting of contextual factors in the studies challenge the widespread perception of deforestation as being directly caused by bush fires, overgrazing and woodcutting. Instead, agricultural expansion (which often includes forest clearing) and pre-existing biophysical factors were the most frequently cited factors in shaping environmental outcomes. Conclusions This systematic map suggests that there are environmental, socioeconomic and health consequences associated with woodfuel value chains in Sub-Saharan Africa. However, the literature also shows a weak and geographically limited evidence base to justify the above claims. We argue that policy formulation processes targeting woodfuels in SSA require more solid, coherent and broad body of knowledge, especially for such a vital sector in rural economies. Thus, there is an urgent need to design and undertake research using robust methodologies, at appropriate scales that further takes into account the interrelationships between environmental and socio-economic outcomes in order to generate substantial and reliable evidence for informed policy formulation.

In this study, the emissions of three different generations of firewood stoves were characterized to test their sustainability with this new problematic. Organic Carbon (OC) and Elemental Carbon (EC) emissions were particularly targeted. After an investigation of the OC/EC measurement method, a specific protocol was developed, validated and optimized in order to measure OC/EC from direct samplings in the flue gas, without diluting or cooling systems. Carbon monoxide (CO), Total Suspended Particles (TSP) and Total Hydrocarbon (THC) emissions were followed too. To go further in the characterization and in the differentiation of the particles emitted from each kind of stoves, a Field Emission Gun Scanning Electron Microscope (FEG SEM) was used. The medium generation emitted 40% less mass of OC than the previous one. Concerning the new generation, emissions were reduced in mass about 98% for the EC and 40% for the OC compared to the old generation.

The importance of forest resources for rural communities' livelihoods has increasingly been recognized over the last three decades. Forests provide food, generate incomes, provide supporting (nutrient cycling, pollination), and regulating (climate, diseases, water regulation and purification) services for agriculture, in addition to their aesthetic, cultural and spiritual role. However, most of the studies on forest resource use do not focus on the role of landscape organization in addressing the impact of climate variability and the risk of food insecurity. This study aims to examine the contribution of woodlands and trees towards decreasing the risk of food insecurity and the importance of landscape structure and composition in coping with food shortages. It took place in two villages in Burkina Faso, on both ends of the woodlands and tree-cover spectrum. We demonstrate that in both landscapes, ecosystem goods, such as shea nuts and fuelwood, represent a safety net for households during food shortage periods. We demonstrate that households shape their adaptive strategies differently depending on the resources available and the structure of the landscape. People living in a landscape with a savannah matrix (Sorobouly) rely on fuelwood trade to purchase cereals, while those living in a landscape with a parkland matrix (Kalembouly) rely on shea nuts. Agricultural, environmental and climate change policies that reinforce the rights of the most vulnerable to access key resources provided by these landscapes and development programs which assure their sustainable use will simultaneously enhance food security and increase their adaptive capacity in the face of climate change and variability.

The study presented in this article focuses on firewood and charcoal in Cameroon. The study analyses subnational secondary data combined in some cases with additional collected data on firewood and charcoal consumption as well as their market prices. The findings estimate a total consumption of 2.2 million metric tons for firewood and 356,530 metric tons for charcoal in urban areas of Cameroon. Firewood and charcoal contribute to the GDP for an estimated amount of US$ 304 million representing 1.3% of the GDP of Cameroon. In addition, the sub-sector provides about 90,000 equivalent full time jobs while 80% of the people in Cameroon depend entirely on wood-energy for household energy supply. Unfortunately, there is no government policy to develop the wood-energy sub-sector.; El presente artículo describe un estudio llevado a cabo sobre la leña y el carbón en Camerún. El estudio se basa en el análisis de datos secundarios recientes a nivel subnacional, que han sido completados en ciertos casos con datos adicionales sobre el consumo de leña y carbón, así como sus precios de mercado. Los resultados indican que el consumo total en áreas urbanas de Camerún gira en torno a 2,2 millones de toneladas de leña y 356.530 toneladas de carbón. Se estima que la leña y el carbón contribuyen con 304 millones de US$ al PIB de Camerún, lo que corresponde a un 1,3%. Además, el subsector genera un equivalente de 90.000 trabajos a tiempo completo, y el 80% de la población de Camerún depende completamente de la dendroenergía para el suministro de energía en el hogar. Desafortunadamente, no hay una política gubernamental para desarrollar el subsector de la dendroenergía.; L'étude présentée dans cet article s'est intéressée au bois de feu et au charbon de bois au Cameroun. L'étude s'est basée sur l'analyse des données secondaires issues d'études récentes conduites à des niveaux sous nationaux, complétée dans certains cas, par des collectes additionnelles de données tant sur la consommation du bois de feu et du charbon de bois que sur les prix de vente de ces produits sur le marché. Les résultats ont été que, les consommations totales en zone urbaines du Cameroun sont estimées à 2,2 millions tonnes et 356.530 tonnes pour le bois de feu et le charbon de bois respectivement. Le bois de feu et le charbon de bois contribuent au PIB pour un montant estimé à 304 millions de dollars US représentant 1,3% du PIB du Cameroun. De plus, le sous-secteur procure environ 90.000 emplois équivalents plein temps tandis que 80% de la population dépend entièrement du bois-énergie pour l'approvisionnement des ménages en énergie. Malheureusement, il n'existe pas de politique gouvernementale pour le développement du sous-secteur bois-énergie.

With population growth and urban development, African demand for wood is growing steadily. Most of the countries of Africa are facing a major challenge: reconciling their economic development, which often implies deforestation, with the maintenance of tree canopy cover, which provides resources and basic services for rural and urban populations.

Avec l'accroissement démographique et le développement des villes, la demande africaine en bois ne cesse de croître. La plupart des pays du continent sont confrontés à un défi majeur : concilier leur développement économique, souvent synonyme de déforestation, avec le maintien d'un couvert arboré synonyme de ressources et de services essentiels aux populations rurales et urbaines.

To contribute to the development of methods for the sustainable management of forest ecosystems in Central Africa, the following research question was addressed: can analyses of land cover change help to understand and document the spatial organization and mechanisms of forest degradation? To answer this question in the Democratic Republic of Congo, the Makala project mapped the tree and forest resources of Kinshasa's wood-fuel supply basin and attempted to predict how they would evolve in the future. Maps were made for four periods (1984, 2001, 2006 and 2012) using a mosaic of four LANDSAT images. The above-ground biomass was estimated in 2012 using forest inventories in 317 plots distributed across the four types of plant cover found on the Bateke plateau (4,337 trees and 44 species were recorded). This inventory data combined with the satellite data allowed us to make the first comprehensive assessment of above-ground biomass in the study area. Between 2000 and 2012, the average volume of wood-fuel fell by more than 50%. Over the entire period studied (1984 to 2012), carbon stocks fell by 75%. In the wood-fuel supply area for Kinshasa, the drastic loss of forest cover, shortened fallow periods, savannah encroachment and the decline of biomass and carbon stocks are clear signals of degradation. However, these initial estimations were derived from a small sample that was extrapolated to the entire supply area. It would be very useful to increase sampling in order to obtain more accurate and realistic figures. The experience of the Makala project clearly shows that the analysis of land cover change helps to understand and document the spatial organization and mechanisms of forest degradation. However, only with a sound wood-fuel resource policy and sustainable community land management, combined with very dynamic tree reintroduction on agricultural land, will it be possible to initiate a sustainable process of restoration.

Background The vast majority of households in Sub-Saharan Africa (SSA) depend on wood energy—comprising firewood and charcoal—for their daily energetic needs. Such consumption trends are expected to remain a common feature of SSA’s wood energy production and supply chains, at least in the short- to medium-terms. Notwithstanding its importance, wood energy generally has low priority in SSA national policies. However, the use of wood energy is often considered a key driver of unsustainable management and negative environmental consequences in the humid and dry forests. To date, unsystematic assessments of the socio-economic and environmental consequences of wood energy use have underplayed its significance, thus further hampering policy debates. Therefore, a more balanced approach which considers both demand and supply dynamics is needed. This systematic map aims at providing a comprehensive approach to understanding the role and impacts of wood energy across all regions and aspects in SSA. Methods The objective of this systematic map is to collate evidence from studies of environmental and socio-economic impacts of wood energy value chains, by considering both demand and supply within SSA. The map questions are framed using a Populations, Exposure, Comparators and Outcomes (PECO) approach. We name the supply and demand of wood energy as the “exposure,” composed of wood energy production, harvesting, processing, and consumption. The populations of interest include both the actors involved in these activities and the forest sites where these activities occur. The comparator is defined as those cases where the same wood energy activities occur with i) available/accessible alternative energy sources, ii) regulatory frameworks that govern the sector and iii) alternative technologies for efficient use. The outcomes of interest encompass both socioeconomic and environmental impacts that can affect more than the populations named above. For instance, in addition to the direct socioeconomic impacts felt by participants in the wood energy value chain, forest dwellers may experience livelihood changes due to forest degradation caused by external harvesters. Moreover, intensified deforestation in one area may concurrently lead to forest regeneration in another.

The use of woodfuel to meet the demand for energy has regularly reappeared on both European and African political agendas over the last 50 years. In the 1980s, it no longer seemed necessary or even desirable to use wood to meet energy demand. But in the last decade, energy specialists, economists, industrialists, and politicians have begun to (re)consider woodfuel as a sector worthy of interest given the rising fuel prices, fuel scarcity, and increasing awareness of climatic change. At present, the hopes, the debates, and the progresses surrounding uses of woodfuel are very different in northern and southern countries, but the trends and challenges appear to converge. In this paper, we argue that woodfuel has the potential to fulfill the increased energy demand and to play a sustainable role in the energy sector. But anxieties and lock-ins remain. Many forestry specialists and environmentalists are putting up ideological resistance. Others question the capacity of existing forests to meet this increased demand in a sustainable way. At the very least, a trend toward industrialization and privatization of the woodfuel sector would have major implications for ownership and forest management. However, despite concerns surrounding woodfuel, we argue that the extent of the energy demand to be met and the pressure from new private industrial players will oblige the forestry sector to broaden its position. It will have to consider the possibility of entering a new transformative era that not only includes woodfuel but also has implications for forest management, rights of access, justice, and sustainability. WIREs Energy Environ 2015, 4:156-170. doi: 10.1002/wene.115. (Resume d'auteur)

La leña sigue representando para la mayor parte de la región centroamericana, y especialmente para Honduras, una parte importante de la oferta energética primaria, y una de las causas principales de la deforestación y degradación de los bosques. En las últimas décadas la cooperación internacional, en alianza con los gobiernos e instituciones académicas, ha intentado promover el desarrollo sostenible de la dendroenergia en la región. Esto se ha realizado a través de la implementación de programas que han impulsado el establecimiento de plantaciones dendroenergéticas. En base a informes de proyectos y estudios realizados en la región, el artículo ordena y analiza desde un enfoque comparativo las enseñanzas relevantes de estas experiencias. Se consideran los resultados de la investigación disponible realizada en la región en términos de potencial energético, rendimientos, y requerimientos ambientales para la plantación de géneros como Acacia, Eucalyptus, Pinus, Leucaena, entre otros. Se analizan los principales impactos y obstáculos enfrentados por los programas regionales y nacionales implementados, de donde se derivan aprendizajes que servirán para enfrentar los nuevos retos de la dendroenergia en la región.

An ethnobotanical survey was carried out on 31 woody species recorded in the protected forests of Dan Kada Dodo and Dan Gado in south-central Niger. Semi-structured interviews with local population were conducted between June and September 2012 in seven bordering villages in which five are predominantly from the Hausa ethnic group and two are from the Fulani ethnic group. A total of 256 people were randomly selected and interviewed. Plant parts and species use-value and preferences were evaluated. Local populations were found to use forest resources for varied and vital needs. The use category wood energy was dominant (20.38%), followed by medicinal uses (19.42%). Wood leaves and roots were the most used parts of the plants. There is significant difference (P

This study characterizes the tree vegetation around Bamba, a village adjacent to the northern part of the river Niger in Mali. Tree species are surveyed in an area of 1300 km 2 . Two human activities in this area affect tree distribution: herd grazing and fuel-wood logging. The characteristics of this tree vegetation are related to the spatial distribution of villages, wells and the river Niger. Two tree vegetation gradients are identified: a North–South gradient in terms of tree density and logging intensity, and a radial gradient around wells in terms of regeneration. Species composition is similar throughout the entire area. Tree density and logging intensity increase from North to South. This gradient may be explained by the amount of ground-water due to the river Niger and by the distance to villages. Seedling density increases with distance from wells. This gradient may be related to herd trampling. Both gradients are non-linear: a threshold distance of 4 km is associated with the North–South gradient, whereas that for the radial gradient is 9 km.

À Madagascar, les politiques de lutte contre la déforestation évoluent voire se confrontent au cours du temps. Dans les années 1990, les bilans des approches passées ont conduit à s’orienter vers une décentralisation de la gestion des forêts. Après quinze années d’existence, l’effet de ces politiques au niveau local a été analysé afin d’évaluer les opportunités et les contraintes offertes par ces réformes pour la gestion des forêts et pour le déve- loppement des populations rurales. Cette analyse a été mise en perspective avec une étude de cas au Niger. Les résultats en sont présentés succinctement. Les politiques de décentralisation sont analy- sées comme une stratégie pour faire face à un diagnostic de dégradation des forêts qui peut être assimilé à un diagnostic de vulnérabilité. Ces politiques se sont focali- sées sur le bois énergie, considéré comme usage principal des forêts. Cependant, la mise en œuvre de ces politiques au niveau local a entraîné des changements sur d’autres usages des écosystèmes fores- tiers en raison des interactions entre ces usages. L’article propose des pistes de réflexions pour un ajustement des poli- tiques de décentralisation de la gestion des forêts à Madagascar et au Niger. Ces pistes consistent à intégrer la diversité des usages forestiers dans la mise en œuvre des transferts de gestion et à déve- lopper une gestion adaptative qui émerge d’une interaction entre acteurs établie très en amont dans les processus de transfert de gestion.