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For forest sustainability and vulnerability assessment, the landscape scale is considered to be more and more relevant as the stand level approaches its known limitations. This review, which describes the main forest landscape simulation tools used in the 20 European case studies of the European project “Future-oriented integrated management of European forest landscapes” (INTEGRAL), gives an update on existing decision support tools to run landscape simulation from Mediterranean to boreal ecosystems. The main growth models and software available in Europe are described, and the strengths and weaknesses of different approaches are discussed. Trades-offs between input efforts and output are illustrated. Recommendations for the selection of a forest landscape simulator are given. The paper concludes by describing the need to have tools that are able to cope with climate change and the need to build more robust indicators for assessment of forest landscape sustainability and vulnerability.

For forest sustainability and vulnerability assessment, the landscape scale is considered to be more and more relevant as the stand level approaches its known limitations. This review, which describes the main forest landscape simulation tools used in the 20 European case studies of the European project “Future-oriented integrated management of European forest landscapes” (INTEGRAL), gives an update on existing decision support tools to run landscape simulation from Mediterranean to boreal ecosystems. The main growth models and software available in Europe are described, and the strengths and weaknesses of different approaches are discussed. Trades-offs between input efforts and output are illustrated. Recommendations for the selection of a forest landscape simulator are given. The paper concludes by describing the need to have tools that are able to cope with climate change and the need to build more robust indicators for assessment of forest landscape sustainability and vulnerability. The INTEGRAL project has received funding from the European Union’s Seventh Programme for research, technological development and demonstration under grant agreement No. 282887. http://www. integral-project.eu/. Moreover, financial support by the Transnational Access to Research Infrastructures activity in the 7th Framework Programme of the EC under the Trees4Future project (No. 284181) for conducting the research is gratefully acknowledged. This research has also received funding from the European Union H2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 691149 (SuFoRun). Researcher Jordi Garcia-Gonzalo was supported by a “Ramon y Cajal” research contract from the MINECO (Ref. RYC-2013-14262) and has received funding from CERCA Programme/Generalitat de Catalunya. This paper could be achieved thanks to support of EFIATLANTIC donors: Conseil regional d’Aquitaine, Ministère de l’agriculture et de la forêt.

Background The quantitative impact of forest management on forests’ wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation length have seldom been directly quantified on landscape scale. Methods Two sites of similar fertility but subject to contrasted forest management were studied with detailed inventories: one in Germany, the other in Romania, and compared with the respective national forest inventories. In Romania, regulations impose very long rotations, low thinnings and a period of no-cut before harvest. In contrast, tending and thinnings are frequent and intense in Germany. Harvests start much earlier and must avoid clear cutting but maintain a permanent forest cover with natural regeneration. While Germany has an average annual wood increment representative for Central Europe, Romania represents the average for Eastern Europe. Results The lack of tending and thinning in the Romanian site resulted in twice as many trees per hectare as in the German site for the same age. The productivity in Romanian production forests was 20 % lower than in Germany despite a similar fertility. The results were supported by the data from the national forest inventory of each country, which confirmed that the same differential exists at country scale. Furthermore, provided the difference in rotation length, two crops are harvested in Germany when only one is harvested in Romania. The losses of production due to a lower level of management in Romania where estimated to reach 12.8 million m3.y-1 in regular mountain production forests, and to 15 million m3.y-1 if managed protection forest is included. Conclusions The productivity of Picea and Fagus mountain forests in Romania is severely depressed by the lack of tending and thinning, by overly long rotations and the existence of a 25-years no-cut period prior to harvest. The average standing volume in Germany was 50 % lower than in Romania, but the higher harvesting rate resulted in more than doubling wood production. Considering the mitigation effects of climate change by forests, it emerges that the increase in standing volume of forests in Romania is smaller than the additional harvest in Germany which serves fossil fuel substitution.

Des analyses dendro-anthracologiques ont été réalisées sur 19 sites archéologiques qui se concentrent en plaine de Limagne et se répartissent du cinquième millénaire av. J.-C. au iiie siècle ap. J.-C. Elles concernent différentes structures de combustion, structures en creux et structures d’habitat. Ces données indiquent un changement dans l’approvisionnement en bois entre le premier et le second Âge du Fer : le hêtre devient alors majoritaire devant le chêne. Sur la base des données polliniques, cette évolution ne semble pas être en relation avec un changement dans la disponibilité du bois localement, la hêtraie étant déjà existante dans la région depuis l’Âge du Bronze. La diversité en taxons héliophiles croissante au cours du temps, l’augmentation des largeurs moyennes de cernes des charbons de chêne caducifolié, ainsi qu’une multiplication des sites ayant livré plus de 10 % de bois de petit calibre (branches, brindilles), révèlent un peuplement végétal de plus en plus hétérogène, ouvert et la mise en place d’une végétation basse de reconquête. Cette évolution du couvert végétal est synchrone d’une intensification de l’occupation des sols en constante progression jusqu’à l’Empire romain durant lequel le réseau parcellaire et de villae est très dense en Basse Auvergne. Les analyses anthracologiques présentées ici sont une succession de cas particuliers qui réunis et interprétés ensemble permettent d’esquisser une histoire de la gestion de la ressource en bois du Néolithique à la conquête romaine. Dendro-anthracological analyses were performed on 19 archaeological sites located in the Limagne plain and dated from the 5th millennium BC to the 3rd century AD. Analyses concerned different archaeological contexts such as fireplaces, post-holes and settlement sites. The data shows a change in wood supply with time, namely the replacement of oak by beech between the 1st and the 2nd Iron Age. On the light of pollen records, this change does not seem to be related to a contemporary change in local wood availability as beech forests were already present in the area from the Bronze Age. Besides, the higher diversity of heliophilous taxa, the increasing trend of the oak fc. charcoal average tree ring width and the proliferation of sites reporting more than 10 % of small coals - i.e. branches, twigs - reveal a heterogeneous vegetation context which included a low undergrowth cover like as hedges and thickets. Such environmental diversification reported from the early Iron Age, which is further stressed from the second Iron Age, corroborates the land use pattern documented in the Basse Auvergne from this age to the Roman period. This shows a progressively denser settlement with a land plot network and villae. Anthracological analyses presented in this article are a series of particular case-studies which interpreted all together enable us to define the timber resource management history of the Basse Auvergne from the Neolithic to the Roman period.

National audience; Dendro-anthracological analyses were performed on 19 archaeological sites located in the Limagne plain and dated from the 5th millennium BC to the 3rd century AD. Analyses concerned different archaeological contexts such as fireplaces, post-holes and settlement sites. The data shows a change in wood supply with time, namely the replacement of oak by beech between the 1st and the 2nd Iron Age. On the light of pollen records, this change does not seem to be related to a contemporary change in local wood availability as beech forests were already present in the area from the Bronze Age. Besides, the higher diversity of heliophilous taxa, the increasing trend of the oak fc. charcoal average tree ring width and the proliferation of sites reporting more than 10 % of small coals -i.e. branches, twigs reveal a heterogeneous vegetation context which included a low undergrowth cover like as hedges and thickets. Such environmental diversification reported from the early Iron Age, which is further stressed from the second Iron Age, corroborates the land use pattern documented in the Basse Auvergne from this age to the Roman period. This shows a progressively denser settlement with a land plot network and villae. Anthracological analyses presented in this article are a series of particular case-studies which interpreted all together enable us to define the timber resource management history of the Basse Auvergne from the Neolithic to the Roman period.

Activated carbon fibers were prepared from liquefied wood through stream activation. The effects of activation temperature and time on the microstructure and surface functional groups of the liquefied wood activated carbon fibers (LWACFs) were studied using analysis of burning behavior, X-ray diffraction, nitrogen adsorption-desorption isotherms, X-ray photoelectron spectroscopy, and SEM. The results showed that the burn-off value of the LWACFs increased gradually with the increase in temperature or time. All the LWACFs were far from being structurally graphitized, and in general, as temperature or time increased, the degree of graphitization and thickness of crystal structure increased. In addition, the LWACFs possessed rich micropores, and their specific surface area, pore volume, micropore size, and mesopore quantity were directly related to the activation temperature or time. The maximum specific surface area was found to be 2641 m2/g. The fractal dimension values of all samples were close to 3, indicating that their surfaces were very rough. Furthermore, with an increase in temperature or time, the elemental content of carbon increased, while that of oxygen decreased. Meanwhile, as the temperature or time increased, the relative content of graphitic carbon decreased, whereas that of carbon bonded to oxygen-containing functions increased. The surface of samples prepared at higher temperature or with longer time formed a considerable amount of holes.

International audience; The objective of this paper is to propose a method for simulating and predicting the evolution of wood resources in the ‘Landes de Gascogne’ region. Lemoine’s growth and yield model has been successfully utilized to predict future timber resources from existing data collected in two successive surveys (1977 and 1988) conducted by the National Forest Inventory (NFI). Lemoine’s model was calibrated by analysing the error in estimation of stand features between the NFI plots and experimental plots originally used to built Lemoine’s model. The proposed corrected term is based on the best linear unbiased predictor of the error. The calibrated model exhibited a better accuracy than the original model version. We suggest that coupling the calibrated Lemoine’s model with NFI data is a useful method for predicting timber resources at a regional level.; L’objectif de cet article est de proposer une méthode de prédiction de l’évolution de la ressource dans les Landes de Gascogne. Le modèle de production de Lemoine a été employé avec succès pour évaluer la disponibilité en bois de la région, en utilisant les données des deux cycles de l’Inventaire Forestier National (IFN ; 1978 et 1988). Le modèle a été calibré, en considérant l’erreur d’estimation des caractéristiques dendrométriques des peuplements, entre les placettes de l’IFN et les parcelles expérimentales employées pour construire le modèle. Le terme de correction est basé sur le meilleur prédicteur linéaire non biaisé de l’erreur. La validation du modèle calibré a été menée sur des placettes non utilisées dans la procédure de calibration: la précision dans les prévisions a été sensiblement améliorée. Nous suggérons que le couplage des données recueillies par l’IFN et du modèle calibré constitue un bon outil pour prédire la disponibilité régionale en bois.

The objective of this paper is to propose a method for simulating and predicting the evolution of wood resources in the ‘Landes de Gascogne’ region. Lemoine’s growth and yield model has been successfully utilized to predict future timber resources from existing data collected in two successive surveys (1977 and 1988) conducted by the National Forest Inventory (NFI). Lemoine’s model was calibrated by analysing the error in estimation of stand features between the NFI plots and experimental plots originally used to built Lemoine’s model. The proposed corrected term is based on the best linear unbiased predictor of the error. The calibrated model exhibited a better accuracy than the original model version. We suggest that coupling the calibrated Lemoine’s model with NFI data is a useful method for predicting timber resources at a regional level., L’objectif de cet article est de proposer une méthode de prédiction de l’évolution de la ressource dans les Landes de Gascogne. Le modèle de production de Lemoine a été employé avec succès pour évaluer la disponibilité en bois de la région, en utilisant les données des deux cycles de l’Inventaire Forestier National (IFN ; 1978 et 1988). Le modèle a été calibré, en considérant l’erreur d’estimation des caractéristiques dendrométriques des peuplements, entre les placettes de l’IFN et les parcelles expérimentales employées pour construire le modèle. Le terme de correction est basé sur le meilleur prédicteur linéaire non biaisé de l’erreur. La validation du modèle calibré a été menée sur des placettes non utilisées dans la procédure de calibration: la précision dans les prévisions a été sensiblement améliorée. Nous suggérons que le couplage des données recueillies par l’IFN et du modèle calibré constitue un bon outil pour prédire la disponibilité régionale en bois.