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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.

The performance of private forest governance systems, such as the standard and approach developed by the Forest Stewardship Council (FSC), is often assessed at the local level although they also have an indirect influence on public policies at the national level. Such spillover effects must be understood to assess the effectiveness of certification in contributing to improved forest governance. With this purpose, this article analyses the influences of the implementation of FSC standards on changes in forest governance in Cameroon, Congo and Gabon based on perceptions of 43 “knowledgeable” actors of FSC natural forest management. The information was collected through the use of semi-open and open interviews, and rankings. Findings show that perceived FSC influence on forest governance has followed two pathways: (a) a clear impact on stakeholder participation and timber traceability; and (b) a limited impact on improving national governance, as illustrated by the lack of global improvement in resource management practices or in biodiversity conservation. Moreover, interviewees agreed that struggles against corruption and transparency have not been impacted by the FSC certification in the Congo Basin. This mitigated influence of FSC on forest governance is first explained by a limited spillover effect of the virtuous practices of the seven FSC-certified companies on the national logging sector. Secondly, progress in FSC certification has been little taken up by public policies, which remain the main leverage for action on forest governance in producing countries.

What is meant by sustainability depends on what is sustained and at what level. Sustainable forest management, for example, requires maintenance of a variety of values not the least of which is sustained timber yields (STYs). For the 1 Bha of the world's forests subjected to selective or partial logging, failures to maintain yields can be hidden by regulatory requirements and questionable auditing practices such as increasing the number of commercial species with each harvest, reducing the minimum size at which trees can be harvested, and accepting logs of lower quality. For assertions of STY to be credible, clarity is needed about all these issues, as well as about the associated ecological and economic tradeoffs. Lack of clarity about sustainability heightens risks of unsubstantiated claims and unseen losses. STY is possible but often requires cutting cycles that are longer and logging intensities that are lower than prescribed by law, as well as effective use of low-impact logging practices and application of silvicultural treatments to promote timber stock recovery. These departures from business-as-usual practices will lower profit margins but generally benefit biodiversity and ecosystem services. Significance Statement Commitments to sustainable forest management (SFM) deserve praise but also scrutiny. Here we examine the sustained timber yield (STY) component of SFM for the 25% of Earth's forest subjected to selective logging. Legitimacy of STY claims depend on whether, over time, the number of species included in yield calculations increases, minimum cutting diameters decrease, or lower quality logs are accepted. STY is possible without such dubious accounting practices if harvest intensities and collateral damage decrease, harvest intervals increase, and treatments are applied to promote recovery. These changes will reduce profits relative to those of timber mining, but climate-change mitigation funds should be available to cover some of the costs given the carbon and other benefits of responsible forest management.

Tropical Secondary Forests (SFs) are vulnerable forest systems growing in areas that have been subject to unsustainable human activities leading to deforestation. SFs account for swathes of tropical forest landscapes that have lost their capacity to provide a high level of goods and services. They are also located in highly dynamic and human-pressured landscapes and are vulnerable to natural and human-induced catastrophic events, such as hurricanes or fires. Without appropriate silvicultural management to increase their economic value and restore their ecological functions, they often become degraded and are sometimes cleared for more short-term economically productive activities. Given the increasing demand for tropical timber in recent decades that will continue in the near future, we suggest that active restoration geared towards wood production is an opportunity for SF conservation. Promoting sustainable wood production -i.e. associated with other environmental services- in these disturbed forest ecosystems is also a way to reduce logging pressure on the remaining intact primary tropical forests, indeed, this may be the most important reason to enhance active restoration aimed at wood production in tropical SFs worldwide. Future research in forest ecology and management should produce experimental evidence of enhanced production of wood and ecosystem services in SFs through appropriate silvicultural experimentations.

Recognizing the potential interactions and synergies between adaptation and mitigation in land-use policies in general and forest policies in particular, research on climate change policy has increasingly focused on integrating both objectives simultaneously (hereafter “interaction model”). However, while support exists for the integration of adaptation and mitigation, very few policies have successfully integrated both objectives in practice (hereafter “separation model”). In addition to the interaction and separation models, we introduce the “adaptation-first model”—an approach to climate policy integration that centers adaptation at the core of forest management, with mitigation as one benefit amongst others—and assess whether it more effectively characterizes the practical realities of forest management than the separation or interaction models. Drawing on a review of policy documents, a survey (n = 48) and interviews (n = 22) with government managers in British Columbia (BC), Canada, we analyze which of the three models have been used for integrating climate objectives into BC’s forest policy and explore views of government managers on the relationships and trade-offs between adaptation and mitigation and which model should be prioritized for their integration into forest management. Our analysis of climate-focused forest policy documents indicates that a possible shift from the separation to the interaction model is taking place in BC. However, our results also indicate that while government managers support the interaction model in principle, they perceive numerous barriers to policy integration that may prevent the shift towards the interaction model to materialize in practice. Because of the fundamental perceived differences in the levels at which adaptation and mitigation intervene in decision-making, government managers in our study were generally more comfortable with the adaptation-first model, which ultimately suggests the need to rethink how we frame climate integration into forest management and policies.

In 2006, the Brazilian Forest Service (SFB) started an ambitious program to establish forest concessions so as to provide a legal framework for long-term sustainable timber production in Amazonian forests. Forest concessions in the Brazilian Amazon currently cover only 1.6 million ha (Mha) but we estimate the area of all potential concessions as 35 Mha. This paper assessed the conditions under which the present and potential concession system can ensure an annual production of 11 Mm3. yr−1 to meet the estimated present timber demand. For this we used the volume dynamics with differential equations model (VDDE) calibrated for the Amazon Basin with a Bayesian framework with data from 3500 ha of forest plots monitored for as long as 30 years after selective logging. Predictions of commercial volume recovery rates vary with location. We tested 27 different scenarios by using combinations of initial proportion of commercial volume, logging intensity and cutting cycle length. These scenarios were then applied to the current area of concessions and to the area of all potential concessions (35 Mha). Under current logging regulations and the current concession area (mean logging intensity of 15–20 m3.ha−1, a harvest cycle of 35 years and an initial commercial timber volume proportion of 20%), timber production can be maintained only for a single cutting cycle (35 years). Only the scenario with a logging intensity of 10 m3ha−1 every 60 years with a 90% initial proportion of commercial timber species can be considered as sustainable. Under this scenario, the maximum annual production with the present concession areas is 159,000 m3 (157–159), or less than 2% of the present annual production of 11 Mm3. When considering all potential concession areas (35 Mha), under current rules, the total annual production is 10 Mm3yr−1 (2–17 Mm3yr−1, 95% credibility interval) but is not maintained after the first logging cycle. Under the most sustainable scenario (see above) and a concession area of 35 Mha, the long-term sustainable annual production of timber reaches only 3.4 Mm3yr−1. Based on these results we argue that the concession system will not be able to supply the timber demand without substantial reforms in natural forest management practices and in the wood industry sector. We argue that alternative sources of timber, including plantations linked with forest restoration initiatives, must be promoted.

HIGHLIGHTSBenishangul-Gumuz Regional State (BGRS) has the highest proportion and area of natural bamboo forests in Ethiopia, mostly lowland bamboo (Oxytenanthera abyssinica).In BGRS, bamboo resources were poorly managed and wasting away.There is a lack of bamboo-focused training among foresters, and local bamboo value chains are under-developed.We characterize the existing bamboo business models, and the state and non-state actors influencing the sustainable management of bamboo resources and bamboo value chains.We identify the support needed by small-scale enterprises, including training in business and bamboo-specific technical skills, access to financing adapted to their capacity and needs, improved infrastructure and market linkages, and land use planning that accounts for the economic and environmental values of bamboo resources.SUMMARYWe document the perceptions, practices and policy options in managing lowland bamboo [Oxytenanthera abyssinica] in Benishangul Gumuz Regional State (BGRS) in Ethiopia, particularly to enable small-scale enterprises (SSE) to become more active in this field. This region hosts the largest extent of natural bamboo forests in Ethiopia. There is a recent push to realize bamboo's economic and environmental potential in Ethiopia, which puts SSEs as crucial actors. There is little or scattered published information on local perceptions and practices surrounding natural bamboo forest management and options for realizing bamboo's potential from a subnational/local perspective in Africa, including in Ethiopia. In 2018, we conducted a literature review, spatial analysis, participatory mapping, and interviewed experts working in governmental and non-governmental organizations and local stakeholders in BGRS. We find some consensus of the environmental importance of bamboo. In contrast, there is some debate at the subnational level about the economic importance of bamboo, leading to decisions favouring other land uses. Bamboo forests in this region suffer neglect, as they are perceived to be ‘owned by no one and used by everyone’ and will continue to be there without management. Lack of market-driven opportunities, bamboo-specific training among foresters, data on economic contributions of bamboo, and regulations or guidelines to support existing laws have prevented effective management of the bamboo resource. There are multiple bamboo management approaches that open economic opportunities for SSEs in the region. There needs to be more clarity on how to secure land use rights over bamboo forests, accessible financing, market linkages, business training, and low-tech/low-cost technologies to encourage the development of bamboo SSEs.

Accurate estimates of commercial volume in tropical forests are key for the implementation of sustainable forest management plans. Because of the lack of local or generic volumetric equations, most forest managers and forestry services are still using traditional expansion factors (i.e., multiplication of the diameter by a given value) to estimate the volume of commercial tree species in the Amazon. Volumetric models were developed through a unique data set of 1,264 fallen trees fully measured in 150 sample plots located across a broad range of forests in Amapá, Brazil. Forest-specific volumetric models were developed and compared with a generic (i.e., across all forests) model and with published equations developed elsewhere in the Amazon. The generic equation performed well in all forest types and allowed precise predictions. The most efficient sampling design to develop volumetric models consists of measuring approximately 50 trees across four different size classes representing the whole population. The form factors (FF) developed locally generated substantial bias but performed better than the traditional FF (0.7). Overall, our results suggest that it is possible to develop accurate generic models to estimate commercial timber volume, and this study can serve as a guideline for forest managers or scientists interested in calibrating volumetric models in a cost-efficient way. Study Implications: This work provides useful information on volumetric modeling methods for Brazilian Amazon tropical forests. Most of the studies in the literature only investigate the classical modeling using regression models considering only boom metrics with or without bark, and, in this way, they provide incomplete and biased total knowledge and estimates for a given population. Therefore, detailed and accurate analyzes are crucial tools for decisionmaking. If the harvesting interventions are carried out without considering the most appropriate method to estimate the total wood stock, there may be damages or even extinction of some species, as has happened with other forest domains in Brazil and in other rainforest regions in the world. In this work, the results clearly show the importance of testing different methodologies and selecting the one best suited for a particular site, as well as carrying out techniques for the sustainable and correct management of the forest. Because the analysis procedures provide only information on how methodologies behave statistically, our results may contribute to a more refined analysis to be applied in the future in similar environments. Currently, the Brazilian forestry sector is looking for alternatives to obtain forest resources within the concept of sustainability. For the Brazilian Amazon tropical forest domain, it is extremely important to achieve a sustainable management of resources through forest management. Most studies in the literature investigate the management of tropical rainforest, whereas there is a lack of scientific information on the transition range for the cerrado. Made available in DSpace on 2020-12-16T09:06:50Z (GMT). No. of bitstreams: 1 CPAF-AP-2020-Accurate-estimation-of-commercial.pdf: 928769 bytes, checksum: dff30beaa41574825f8df54580bc8d84 (MD5) Previous issue date: 2020

The combined and interacting effects of land-use change, resource extraction and climate change threaten the sustainability of millions of mainly smallholder farms in tropical agroforested landscapes. In many of these landscapes, coordinated action among stakeholders at landscape level would help to address challenges such as pests and diseases, price crises and climate change. However, methods to facilitate the co-production of sustainable landscape management in such complex multi-stakeholder systems are currently largely lacking. In this paper, we present a novel approach to explore pathways for the sustainability transition of agroforestry systems. By combining participatory forecasting and backcasting approaches, based on serious games and future vision development, we explore relevant agroforestry management strategies for reaching sustainable future coffee-based agroforestry landscapes. We focused our research on the challenges faced in the main coffee-producing area in Nicaragua. Here, we organized five participatory game sessions to explore farmer decision-making processes, farming strategies and to develop new networks and stimulate social learning among farmers. In the associated backcasting workshop, the most influential game session participants joined technicians, researchers and municipality officials to collectively envision sustainable future landscape management. In all game sessions, farmers developed diversified coffee-based agroforested landscapes characterised by increased density and diversity of shade trees, for the purpose of income diversification as well as forest conservation. During the backcasting workshop, the participants identified policy instruments and community-based solutions for the transition to sustainable landscapes. Our participatory approach facilitated discussion on landscape planning among farmers and other stakeholders and allowed the outline of a pathway towards the collective envisioned future landscape. The combination of participatory forecasting and backcasting proved to be a helpful tool to support multi-stakeholder processes towards sustainable landscape management in this and other complex landscapes.

Luedeling and colleagues argue that we have overestimated the restoration capacity in several regions of the world. Our model predicts the expected optimal tree cover from a combination of 10 environmental variables that were selected through a variable selection procedure to avoid overfitting issues. As detailed in table S1 of our supplementary material, these 10 variables include mean annual temperature, temperature of the wettest quarter, annual precipitation, precipitation seasonality, precipitation of the driest quarter, elevation, hillshade, soil organic carbon, sand content, and depth to bedrock. These ecological variables cover average and seasonal variation in climate and variation in topographic and edaphic conditions. As such, we have done everything that is possible to represent all of the conditions raised by Luedeling and colleagues. Of course, cold and dry conditions are among the main limitations for tree growth, and that is why we have represented these environmental constraints in our model to ensure that we do not predict that trees can exist in regions that are too cold or dry. As explained in the main text, our rigorous k-fold cross-validation (fig. S4A) revealed that our model could explain about 71% of the variation in tree cover without bias (fig. S3, B and C). This means that our model is unbiased at a global scale, but we do not explain 100% of the potential tree cover variation. It is consequently possible to find places where we overestimate or underestimate the potential tree cover—particularly in areas where uncertainties are high, as shown in fig S6. Delzeit and colleagues claim that we overestimate the area available for tree restoration because the expansion of croplands in upcoming decades will reduce the land available for restoration, and because pasture lands are considered as potential land for restoration in our assessment. We agree that, if we continue to expand agricultural land area, there will be a reduction in the land available for restoration. As stated in our analysis, our model estimates the area that is currently available for restoration under present conditions. Of course, any changes in the area of land use will necessarily affect this global total. We exemplified this in our attempts to show how future changes in climate might reduce the area available for restoration. We hope that our analysis can also serve as a stepping stone for future research to evaluate how changes in agricultural land use will affect the potential restoration area. It is true that we included rangelands in the area available for restoration. Of course, much of this land is used for the grazing of animals and so may not be available for complete forest restoration. However, as mentioned in the Report, several studies suggest that it is possible to increase the current tree cover in these areas without limiting food production ([ 1 ][1], [ 2 ][2]), especially when forest cover is relatively low, as is the case for most of the pasture land in our model. Because we removed all urban and agricultural land (i.e., we considered a potential increase of tree cover of 0% in cropland and urban areas), our numbers are likely to underestimate the total area that could currently be covered by trees. Indeed, both croplands and cities constitute great opportunities to increase the current tree cover and to play a major role in mitigating climate change ([ 3 ][3]–[ 5 ][4]). We maintain that our global estimate of the land available for restoration is a conservative one, and we encourage local land owners to use our forest restoration potential map in combination with more detailed local-scale estimates of land use when designing effective restoration strategies. Sheil and colleagues point out that restoring ecosystems might have either positive or negative consequences regarding hydrology. We agree that these effects must be considered as a priority in upcoming research in restoration ecology. 1. [↵][5]1. K.-H. Erb et al ., Nature 553, 73 (2017). [OpenUrl][6] 2. [↵][7]1. K.-H. Erb et al ., Nat. Commun. 7, 11382 (2016). [OpenUrl][8][CrossRef][9][PubMed][10] 3. [↵][11]1. A. Albrecht, 2. S. T. Kandji , Agric. Ecosyst. Environ. 99, 15 (2003). [OpenUrl][12] 4. 1. P. K. Ramachandran Nair, 2. B. Mohan Kumar, 3. V. D. Nair , J. Plant Nutr. Soil Sci. 172, 10 (2009). [OpenUrl][13] 5. [↵][14]1. G. Manoli et al ., Nature 573, 55 (2019). [OpenUrl][15] [1]: #ref-1 [2]: #ref-2 [3]: #ref-3 [4]: #ref-5 [5]: #xref-ref-1-1 "View reference 1 in text" [6]: {openurl}?query=rft.jtitle%253DNature%26rft.volume%253D553%26rft.spage%253D73%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [7]: #xref-ref-2-1 "View reference 2 in text" [8]: {openurl}?query=rft.jtitle%253DNat.%2BCommun.%26rft.volume%253D7%26rft.spage%253D11382%26rft_id%253Dinfo%253Adoi%252F10.1038%252Fncomms11382%26rft_id%253Dinfo%253Apmid%252F27092437%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [9]: /lookup/external-ref?access_num=10.1038/ncomms11382&link_type=DOI [10]: /lookup/external-ref?access_num=27092437&link_type=MED&atom=%2Fsci%2F366%2F6463%2F317.atom [11]: #xref-ref-3-1 "View reference 3 in text" [12]: {openurl}?query=rft.jtitle%253DAgric.%2BEcosyst.%2BEnviron.%26rft.volume%253D99%26rft.spage%253D15%26rft.atitle%253DCARBON%2BSEQUESTRATION%2BIN%2BTROPICAL%2BAGROFORESTRY%2BSYSTEMS%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [13]: {openurl}?query=rft.jtitle%253DJ.%2BPlant%2BNutr.%2BSoil%2BSci.%26rft.volume%253D172%26rft.spage%253D10%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [14]: #xref-ref-5-1 "View reference 5 in text" [15]: {openurl}?query=rft.jtitle%253DNature%26rft.volume%253D573%26rft.spage%253D55%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx

International audience; Pas de résumé spécifique au chapitre

Le changement climatique structure la réflexion prospective sur la gestion durable des forêts, ses évolutions et les besoins d’innovation associés. L’Office National des Forêts présente ici une lecture de l’état des connaissances et des questions posées, à partir de laquelle il a défini ses priorités R&D: le travail a porté sur les principaux aspects de la gestion durable dans la définition de la Conférence d’Helsinki ; le contexte d’application est celui des forêts publiques françaises de métropole. Vis-à-vis du changement climatique, différents points de vue peuvent être adoptés : (i) impacts, prévention des risques et gestion des crises ; (ii) adaptation de la gestion ; (iii) contribution à l’atténuation via la production de bois ; (iv) continuité/qualité des services écosystémiques. L’analyse ne fait pas apparaître de contradictions entre ces différents points de vue, en revanche elle montre (i) les opportunités offertes par les innovations liées à la bioéconomie ; (ii) la nécessité de mieux expliciter les objectifs poursuivis (notamment dans la gestion de la biodiversité) ; (iii) l’intérêt de concentrer l’effort de R&D et innovation sur une série de leviers permettant une gestion active et diversifiée des forêts, gage de continuité des services écosystémiques, atténuation des risques et sécurisation des approvisionnements à la filière bois., Climate change is a major driver of sustainable forest management change. In this paper, R&D engineers of the French National Forest Service reviewed several aspects of sustainable forest management in the light of climate change, in order to identify research and innovation priorities. Climate change may be addressed with various points of view: (i) impacts, risk prevention and crisis management; (ii) adaptation of forest management; (iii) contribution to mitigation through wood production and use; (iv) continuity and quality of ecosystem services. The state of the art and ongoing questions were outlined, according to the specific challenges of a public service managing 25% of the mainland forest area, supplying 40% of exchanged timber, and particularly concerned by different national and European policies (forestry-wood chain, climate change, biodiversity conservation, energy transition, natural risk mitigation and prevention, water). The horizon scan did not suggest obvious contradictions between the different points of view. It showed (i) the potential opportunities brought by innovations linked to bioeconomy (bio-based production chains and markets); (ii) the need for a more explicit and integrated statement of management objectives, especially those regarding timber use and conservation of biodiversity; (iii) the impact of concentrating R&D investments and innovations to support an active, diversified forest management, condition for continuously providing high-quality ecosystem services, mitigating risks and securing a sufficient supply to the forest industries.

Le projet PASSIFOR (pour: Propositions d'Amélioration du Système de Suivi de la biodiversité FORestière; 2012-2015) avait pour objectif de poser des jalons pour l’amélioration du système de suivi de la biodiversité en forêt métropolitaine française. Le projet comportait trois volets. Le premier volet a analysé les réseaux existants de collecte de données sur la biodiversité forestière avec une grille d’analyse commune. De manière assez triviale, les stratégies d’échantillonnage adoptées par chaque réseau identifié correspondent aux objectifs de ce dernier et seul l’inventaire forestier national est véritablement représentatif de la forêt française. L’emprise taxonomique de chaque réseau est souvent limitée, la plupart relevant tout ou partie de la flore vasculaire (notamment les essences d’arbres et arbustes). Parmi les différentes composantes de la biodiversité la composante génétique est la moins couverte par les réseaux analysés. En termes de perspectives, deux réseaux à l’étranger (au Canada et en Suisse) dont l’approche nous parait assez exemplaire sont présentés. Des éléments de comparaison de coûts sont également abordés. Les Coléoptères sont souvent employés comme indicateurs de réponse en écologie forestière appliquée, mais leur hyperdiversité rend difficile leur identification spécifique qui requiert une expertise taxonomique forte et rare. Le second volet de Passifor avait pour objectif de développer et tester des outils moléculaires d’identification de l’espèce de Coléoptères saproxyliques (liés au processus de décomposition du bois). A cet effet, une librairie de référence a été constituée, couvrant 410 espèces et complétant des librairies européennes pré-existantes. Nous avons par ailleurs comparé l’identification des espèces par l’approche morphologique traditionnelle et par métabarcoding. Le taux de détection des espèces par l’approche moléculaire est beaucoup plus forte et moins variable avec les soupes (82% +/- SD=12), qu’avec l’alcool de stockage (32% +/- SD=30). Pour l’ensemble des pièges, près de la moitié des espèces que les taxonomistes ne pouvaient pas identifier morphologiquement ont été identifiées formellement à l’espèce grâce aux séquences produites. L’optimisation du protocole d’échantillonnage et de conditionnement pour maximiser le taux d’identification moléculaire est à approfondir. La combinaison [piège à alcool]x[non congélation des échantillons]x[non remplacement de l’alcool de stockage]x[séquençage des soupes] est une des trajectoires les plus efficaces d’après les premiers résultats moléculaires. Toutefois, le protocole d’identification moléculaire sur les échantillons totaux est destructeur, et rend impossible le retour à l’un des spécimens de la soupe initiale, en cas de besoin d’examen morphologique complémentaire. L’objet du troisième volet de PASSIFOR était de bâtir un projet visant à élaborer différentes « maquettes » (assemblages d’éléments existants et à créer) de suivi de la biodiversité en forêt. Il vise une aide aux politiques publiques dans le domaine du suivi continu de la biodiversité, centré sur la forêt en lien avec les autres milieux. En dépit des acquis importants dans le domaine, les indicateurs de biodiversité forestière mobilisent surtout des données dendrométriques, de sorte qu’il manque des informations pour (i) mieux cerner l’état et la dynamique de la biodiversité forestière et (ii) mieux évaluer le lien entre mesures de gestion ou politiques publiques en forêt et biodiversité. Les processus d‘indicateurs forestiers passés ont souvent manqué d’une concertation et d’une explicitation de ses objectifs ou des questions auxquelles il souhaite répondre. Un accent est donc mis dans PASSIFOR sur ces aspects. Un des choix importants concerne donc les données mobilisées – existantes ou à venir : il s’agit de proposer une procédure d’adjonction de données de biodiversité hétérogènes (typiquement des données de sciences participatives) autour d’un réseau de données de biodiversité planifié et recueilli par des professionnels.

National audience; Pas de résumé

article présenté lors du colloque ‘Innovations Sylvicoles’ qui s’est tenu à Pierroton le 3 décembre 2014; French and European forests have been in expansion for nearly a century. Their productivity has increased and their woody biomass stock is steadily increasing. Wood harvests remain significantly below biological growth. This general statement certainly reflects a reality characterized by a great diversity of forests, their methods of management and use of the resource. The fact remains that this change is reflected in a significant increase in exploitable woody biomass. The climate, energy and environmental global challenges society faces lead to consider as a priority the setting out of the energy transition and the green economy. The development of the bio-economy, based on the use of renewable resources from living organisms, namely woody biomass is a major perspective in this direction. Significant technological innovations are expected for this sector. The objectives of intensification of forest production systems are at the convergence of the two dynamics described above. They can be achieved only if we succeed in designing and developing management methods that meet the criteria of sustainable and multifunctional management of systems, taking into account their diversity.; Les forêts françaises et européennes sont en expansion depuis près d’un siècle. Leur productivité s’est accrue et leur stock de biomasse ligneuse est en constante augmentation. Les prélèvements de bois restent nettement inférieurs à l’accroissement biologique. Ce constat global reflète certes une réalité caractérisée par une grande hétérogénéité des forêts, de leurs modes de gestion et de valorisation de la ressource. Il n’en demeure pas moins que cette évolution se traduit par un accroissement sensible de la biomasse ligneuse exploitable. Les défis planétaires climatique, énergétique et environnementaux auxquels la société est confrontée amènent à considérer de façon prioritaire la mise en en œuvre de la transition énergétique et de l’économie verte. Le développement de la bioéconomie, basée sur l’utilisation de ressources renouvelables issues du vivant, notamment la biomasse ligneuse, constitue une perspective majeure dans cette direction. Des innovations technologiques importantes sont attendues pour ce secteur. Les objectifs d’intensification des systèmes de production forestiers sont à la convergence des deux dynamiques décrites ci-dessus. Ils ne pourront être réalisés qu’à condition de concevoir et développer des modes de gestion respectant les critères de gestion durable et multifonctionnelle des systèmes, dans leur diversité.

La forêt guyanaise est un écosystème extrêmement complexe, au patrimoine floristique et faunistique d’une grande diversité. Pendant longtemps, l’exploitation des ressources de et dans l’écosystème était insignifiante et n’avait jamais été pensée dans un cadre de développement durable. Toutefois, la population ayant triplée en une trentaine d’années, passant de 73 000 habitants en 1982 à plus de 220 000 aujourd’hui, la pression des activités humaines sur le milieu forestier est devenue significative, par la production de bois, la chasse, la cueillette, l’agriculture, l’utilisation de la biomasse à des fins énergétiques ou encore l’exploitation aurifère. Les risques environnementaux menacent donc la biodiversité de ce milieu. La prise de conscience de cette situation potentielle a conduit les pouvoirs publics à prendre, dans un contexte international favorable, un certain nombre de mesures en matière de réglementation et de gestion durable et surtout de mise en place d’un réseau d’espaces naturels protégés, dont un récent parc national, le Parc amazonien de Guyane. Forests in French Guiana form an extremely complex ecosystem and have a wealth of flora and fauna of great diversity. During a long time, the exploitation of resources inside and outside the ecosystem was insignificant and was never considered in a sustainable development framework. However, as the population trebled over the last thirty years, the pressure of human activities on the forest environment has become significant, through timber production, hunting, gathering, agriculture, the use of biomass for energy purposes or furthermore gold mining. The awareness to potential risks on environmental biodiversity in an encouraging international atmosphere, has led public authorities to take a number of measures, regulatory, of sustainable management, and above all, in establishing a network of natural protected areas, such as a new National Park, called “The French Guiana Amazonian Park”.

International audience; Tree species is one of the main attributes of forest ecosystems, that modifies resources levels (light, nutrients, water) that affect understory vegetation composition and diversity. This is therefore no surprise that tree species diversity and sometimes abundance or composition are used as biodiversity indicators in various monitoring schemes – e.g. European-level and French level monitoring of sustainable forest management. In a previous study, we have found in some French lowland forests that tree species abundance – and especially late-successional or undergrowth tree abundance – was a better indicator of part of floristic biodiversity than tree species richness and diversity. We here continue this test by analyzing other data from mountain French forests, with a special emphasis on the magnitude of the relationship and its variation in geographical and ecological space. We developed Bayesian statistical models to test these indicators for the richness of ecological groups of understory vegetation species, classified according to their successional status and/or their shade tolerance. These results highlight that if we want to relate pressures to states of biodiversity in an inferential and quantitative perspective it is important to include a potential variation of the relationship with the ecological context. We in particular stress the importance of aspect as a key variable of contextualization of the relation between dendrometric indicators and floristic biodiversity.

Diplôme : Dr. d'Université; This study analyses the international timber trade between Malaysia and Europe with respect to the importance of environmental issues on trade and the role of Malaysia as a major timber exporter to Europe. It also evaluates the comparative advantage of Malaysian wood products and the willingness of French consumers (to represent European communities) to pay for sustainable forest management. The first part gives an overview the clashes of perception between developed and developing countries on the environmental concerns over trade. It was observed that environmental standards may act as non-tariff barriers to exporting countries. In addition, the stringent requirements posed by importing countries on technical, marking and labelling to some extent provide unnecessary barriers to trade. The second part deals with the role of Malaysia as a key player in the tropical timber trade. This part evaluates the main export market for Malaysian wood products to the world. For the purpose of this thesis, the analysis focuses on the European market. From the observations, it was found that the export of wooden furniture surpassed major timber exports in 2004. However, to penetrate the European market, Malaysia has to compete with the Chinese with their lower cost tropical wood products, and Brazil with their advantage in certification and labelling of tropical wood products. In tandem with that, the commitment towards sustainable forest management at national level causes shortage of raw materials in Malaysia. To a certain extent, the internal and external factors create necessary challenges to enter the European market. In the third part, the Balassa approach was used to classify the comparative advantage of Malaysia’s twenty one types of wood products in Europe. It was estimated that Malaysia had high comparative advantage only in five products which were mechanized and intermediary industrial products. The products identified were sawn wood, wooden mouldings, plywood, veneer and builders’ joinery and carpentry. The remaining products had lower comparative advantage and disadvantage to export to the European market based on the Balassa index. In the last part, the estimation on the willingness to pay for sustainable forest management attributes was conducted. Besides that, additional attributes such as fair trade and wood origin were included. A questionnaire was set up using all the attributes reflected in the hypothetical wood flooring product in the market. Based on the result, consumers were willing to pay the highest for the presence of fair trade and wood origin (in this study referring to French origin); nevertheless they were still willing to pay for sustainable aspects of forest. However, the willingness to pay for all the attributes was altered depending on the respondents’ knowledge of forest labelling, their attitudes towards environmental preservation, living area, education level, type of job and income level. In the overall finding of the thesis, all the results from each part were synthesized in a systemic approach simultaneously deliberating on the macro and microeconomic perspectives as well as the dimensions on demand and supply. Overall, the findings suggest that the challenges and constraints facing the Malaysian timber industry indirectly shaped the export of Malaysian wooden products. Malaysia has adapted by going into value-added products to lessen the impact of environment-related trade barriers and to circumvent the shortage of raw materials supply. Malaysia has successfully customized the wooden products to the sustainability and legality requirements of the European market by pursuing the national certification (Malaysian Timber Certification) and being committed to sustainable forest management objectives.; Ce travail étudie l’influence des questions environnementales sur le commerce international à partir des échanges de bois tropicaux Malaisie – Europe, la Malaisie étant un important exportateur de bois. Les avantages comparatifs des produits forestiers Malaisiens sont évalués, ainsi que la propension à payer le bois issu de gestion forestière durable par les consommateurs français (en tant qu’Européens). La première partie envisage les différences de perception entre pays développés et pays en développement pour le lien entre commerce et environnement. Il apparaît que les normes environnementales agissent comme des barrières non-tarifaires. Ces barrières sont accentuées par les critères de marquage, d’étiquetage, et de technologie imposés par les pays importateurs. La seconde partie analyse le rôle clé de la Malaisie dans le commerce des bois tropicaux. Les principaux marchés d’exportation des bois Malaisiens sont évalués. Le marché Européen est étudié plus en détail. Il apparaît que les ventes de meuble ont dépassé en 2004 celles des autres principaux produits forestiers. Sur le marché Européen la Malaisie fait face à la concurrence de produits tropicaux à bas prix venant de Chine, et à celle de produits forestiers éco-certifiés venant du Brésil. Concomitamment, l’engagement de la Malaisie dans une dynamique de gestion plus durable y crée une pénurie relative de matériau brut. La troisième partie calcule l’index de Balassa d’avantage comparatif, pour 21 produits forestiers Malaisiens sur le marché Européen. Seuls 5 produits industriels intermédiaires ou à transformation fortement mécanisée, ont un avantage comparatif marqué. Il s’agit des sciages, moulures, contreplaqués, placages, charpente et menuiserie industrielle. Les autres produits présentent des avantages comparatifs faibles ou même négatifs. La quatrième partie estime la propension à payer pour différents attributs environnementaux, ainsi que d’autres tels le commerce équitable et l’origine géographique. Un questionnaire reprenant ces attributs pour du parquet bois hypothétique a été utilisé. Il semble que les consommateurs soient prêts à rémunérer le plus les critères de commerce équitable et d’origine Française, la gestion durable étant recherchée dans une moindre mesure. La propension à payer les tous les attributs varie en fonction des notions et attitudes qu’ont les consommateurs sur l’éco-certification, l’environnement, ainsi qu’en fonction de leur lieu d’habitation, niveau d’éducation et de revenu, et type de profession. Enfin les résultats des 4 parties sont synthétisés en reliant les échelles micro et macroéconomiques, avec les dimensions de demande et d’approvisionnement. D’une façon générale, les résultats suggèrent que les opportunités et contraintes propres à la l’industrie du bois de Malaisie façonnent les exports de produits. La Malaisie s’adapte en se tournant vers des produits à plus haute valeur ajoutée et à moindre impact environnemental, pour pallier aux barrières commerciales et à la pénurie relative de matériau. La Malaisie s’est dotée d’une certification nationale (Malaysian Timber Certification) propre à remplir les critères de durabilité et de légalité de l’Europe, et s’est engagée la gestion durable des forêts.

L’objectif de l’ouvrage est de mettre en perspective certains enjeux importants de la gouvernance internationale des forêts et de la gestion durable, celle-ci étant entendue comme transposition du développement durable dans le champ forestier. Les grands axes choisis (définitions, acteurs et outils) ouvrent autant de pistes de réflexion visant à prendre en compte les incertitudes, les jeux de pouvoir et les processus souvent conflictuels, autour des grandes problématiques de la préservation et de la conservation des forêts. A côté des discours moralisants et simplificateurs, des stratégies de captation et des modulations idéologiques dont le développement durable fait l’objet, il s’agit, par le biais du terrain forestier, de réintroduire de la complexité et des nuances dans l’analyse d’un concept qui continue de sous-tendre l’action environnementale internationale.

La déforestation, la dégradation des écosystèmes forestiers et les moyens privilégiés pour y remédier, classés sous le terme générique de gestion durable des forêts, sont devenus des sujets importants dans l’agenda politique international depuis les vingt dernières années. Malgré les piétinements au niveau politique, diverses approches de gestion durable et démocratique des forêts ont été expérimentées à travers le monde. Cet article recense les événements politiques majeurs menant aux pourparlers internationaux actuels sur la gestion durable des forêts et analyse sous une perspective interdisciplinaire les principales approches alternatives expérimentées à travers le monde. Ces approches ont été regroupées en trois catégories: écosystémique, intégrée et communautaire. The deforestation, the degradation of forestry ecosystems and the privileged ways to settle the situation, classified under the generic term sustainable management of forests have become important topics on the international political agenda since the last twenty years. Despite stagnations at the political level, various sustainable and democratic management approaches of forests were experimented through out the world. This article takes an inventory of political events leading to actual internationals talks over the long-term management of forest and analyses, under an interdisciplinary perspective, the main alternative approaches experimented across the world. Theses approaches were brought together in three categories: ecosystemic, integrated and community.