Search

Socio‐economic scenarios such as the Shared Socioeconomic Pathways (SSPs) have been widely used to analyze global change impacts, but representing their diversity is a challenge for the analytical tools applied to them. Taking Great Britain as an example, we represent a set of stakeholder‐elaborated UK‐SSP scenarios, linked to climate change scenarios (Representative Concentration Pathways), in a globally‐embedded agent‐based modeling framework. We find that distinct model components are required to account for divergent behavioral, social and societal conditions in the SSPs, and that these have dramatic impacts on land system outcomes. From strong social networks and environmental sustainability in SSP1 to land consolidation and technological intensification in SSP5, scenario‐specific model designs vary widely from one another and from present‐day conditions. Changes in social and human capitals reflecting social cohesion, equality, health and education can generate impacts larger than those of technological and economic change, and comparable to those of modeled climate change. We develop an open‐access, transferrable model framework and provide UK‐SSP projections to 2080 at 1 km2 resolution, revealing large differences in land management intensities, provision of a range of ecosystem services, and the knowledge and motivations underlying land manager decision‐making. These differences suggest the existence of large but underappreciated areas of scenario space, within which novel options for land system sustainability could occur., Key Points: A national‐scale agent‐based model is developed to represent paired climatic and socio‐economic scenarios in the land system. Key scenario characteristics relate to forms of human behavior, interactions and societal preferences. Large differences emerge between scenarios in terms of land management intensities, ecosystem service provision and land sparing., Helmholtz Association http://dx.doi.org/10.13039/501100009318, Natural Environment Research Council http://dx.doi.org/10.13039/501100000270, Climate Resilience Programme, Forestry Commission UK Forestry Commission http://dx.doi.org/10.13039/100017497, UKRI, Engineering and Physical Sciences Research Council http://dx.doi.org/10.13039/501100000266, Global Food Security Programme, DAAD, German Academic Exchange Service London http://dx.doi.org/10.13039/501100001654, Government of the United Kingdom http://dx.doi.org/10.13039/100013986, Deutscher Akademischer Austauschdienst http://dx.doi.org/10.13039/501100001655, Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347, Karlsruhe Institute of Technology http://dx.doi.org/10.13039/100009133, Leibniz‐Gemeinschaft http://dx.doi.org/10.13039/501100001664, https://landchange.earth/CRAFTY, https://doi.org/10.17605/OSF.IO/CY8WE

Virot et al. [E. Virot et al., Phys. Rev. E 93, 023001 (2016)] assert that the critical wind speed at which \ensuremath{\geqslant}50% of all trees in a population break is \ensuremath{\approx}42 m/s, regardless of tree characteristics. We show that empirical data do not support this assertion, and that the assumptions underlying the theory used by Virot et al. are inconsistent with the biomechanics of trees.

Here we introduce the Soil BON Foodweb Team, a cross-continental collaborative network that aims to monitor soil animal communities and food webs using consistent methodology at a global scale. Soil animals support vital soil processes via soil structure modification, consumption of dead organic matter, and interactions with microbial and plant communities. Soil animal effects on ecosystem functions have been demonstrated by correlative analyses as well as in laboratory and field experiments, but these studies typically focus on selected animal groups or species at one or few sites with limited variation in environmental conditions. The lack of comprehensive harmonised large-scale soil animal community data including microfauna, mesofauna, and macrofauna, in conjunction with related soil functions, microbial communities, and vegetation, limits our understanding of biological interactions in soil systems and how these interactions affect ecosystem functioning. To provide such data, the Soil BON Foodweb Team invites researchers worldwide to use a common methodology to address six long-term goals: (1) to collect globally representative harmonised data on soil micro-, meso-, and macrofauna communities, (2) to describe key environmental drivers of soil animal communities and food webs, (3) to assess the efficiency of conservation approaches for the protection of soil animal communities, (4) to describe soil food webs and their association with soil functioning globally, (5) to establish a global research network for soil biodiversity monitoring and collaborative projects in related topics, (6) to reinforce local collaboration networks and expertise and support capacity building for soil animal research around the world. In this paper, we describe the vision of the global research network and the common sampling protocol to assess soil animal communities and advocate for the use of standard methodologies across observational and experimental soil animal studies. We will use this protocol to conduct soil animal assessments and reconstruct soil food webs at sites associated with the global soil biodiversity monitoring network, Soil BON, allowing us to assess linkages among soil biodiversity, vegetation, soil physico-chemical properties, climate, and ecosystem functions. In the present paper, we call for researchers especially from countries and ecoregions that remain underrepresented in the majority of soil biodiversity assessments to join us. Together we will be able to provide science-based evidence to support soil biodiversity conservation and functioning of terrestrial ecosystems. Made available in DSpace on 2022-04-05T05:00:35Z (GMT). No. of bitstreams: 1 George-SO-Global.pdf: 4233169 bytes, checksum: 9faad657460c5d69e137289ebd0e4488 (MD5) Previous issue date: 2022

International audience; Rewilding can be defined as the reorganisation or regeneration of wildness in an ecologically degraded landscape with minimal ongoing intervention. While proposals for rewilding are increasingly common, they are frequently controversial and divisive amongst stakeholders. If implemented, rewilding initiatives may alter the social-ecological systems within which they are situated and thus generate sudden and unforeseen outcomes. So far, however, much of the discourse on the planning and implementation of rewilding has focused on identifying and mitigating ecological risks. There has been little consideration of how rewilding could alter the human components of the social-ecological systems concerned, nor governance arrangements that can manage these dynamics. This paper addresses this gap by proposing a generic adaptive governance framework tailored to the characteristics of rewilding, based on principles of managing complex social-ecological systems. We integrate two complementary natural resource governance approaches that lend themselves to the contentious and unpredictable characteristics of rewilding. First, adaptive co-management builds stakeholder adaptive capacity through iterative knowledge generation, collaboration and power-sharing, and cross-scale learning networks. Second, social licence to operate establishes trust and transparency between project proponents and communities through new public-private partnerships. The proposed framework includes structural and process elements which incorporate a boundary organisation, a decision-into-practise social learning exercise for planning and design, and participatory evaluation. The latter assesses rewilding outcomes and pre-conditions for the continuation of adaptive governance and conservation conflict resolution.

Black locust (Robinia pseudoacacia L.), a species native to the eastern North America, was introduced to Europe probably in 1601 and currently extends over 2.3 × 106 ha. It has become naturalized in all sub-Mediterranean and temperate regions rivaling Populus spp. as the second most planted broadleaved tree species worldwide after Eucalyptus spp. This wide-spreading planting is because black locust is an important multipurpose species, producing wood, fodder, and a source of honey as well as bio-oil and biomass. It is also important for carbon sequestration, soil stabilization and re-vegetation of landfills, mining areas and wastelands, in biotherapy and landscaping. In Europe, black locust is drought tolerant so grows in areas with annual precipitation as low as 500–550 mm. It tolerates dry, nutrient poor soils but grows best on deep, nutrient-rich, well-drained soils. It is a fast-growing tree and the height, diameter and volume growth peak before the age of 20. It mostly regenerates vegetatively by root suckers under a simple coppice system, which is considered the most cost-effective management system. It also regenerates, but less frequently, by stool sprouts. Its early silviculture in production forests includes release cutting to promote root suckers rather than stool shoots, and cleaning-respacing to remove low-quality stems, reduce the number of shoots per stool, and adjust spacing between root suckers. In addition, early, moderate and frequent thinning as well as limited pruning are carried out focusing on crop trees. The species is regarded as invasive in several European countries and its range here is expected to expand under predicted climate changes.

This paper discusses the advance in our understanding of the interaction between wind and trees over the last 25 years. It does this by comparing papers in this special issue of Forestry and a companion volume in Agricultural and Forest Meteorology, based on work presented at the 8th IUFRO Wind and Trees Conference in 2017, with papers published in book format after the 1st IUFRO Wind and Trees Conference in 1993. The analysis is divided into sections on ‘airflow and tree mechanics’, ‘forest management and ecology’, ‘tree adaptation and acclimation’ and ‘modelling and statistical techniques’. It is clear that in the last 25 years large advances have been made in our understanding of airflow and turbulence within and above forest canopies and the wind flow and wind loading around and on individual trees. There have also been important developments in the mechanistic and statistical modelling of wind damage risk to forests. Much of the progress has been aided by the enormous advances in measurement systems, computer power and modelling techniques. Furthermore, this knowledge is beginning to influence the approach to temperate and boreal forest management and the development of systems to mitigate the risk of wind damage. At the same time there has been a growing awareness of the ecological impact of wind in many forests around the world, including tropical forests. However, other areas of the effect of wind on trees have progressed much less in the last 25 years. This includes the process of fatiguing in the root-soil system, both during individual storms and over longer periods, and which is known to be a critical factor in the process of windthrow. In addition the exact nature of damage propagation within forests during a storm, and then in subsequent storms, has received relatively little attention although new studies using advanced computational methods are making advances. Of particular relevance, and despite the known critical importance of tree acclimation to the wind, there have been very few studies in the last 25 years on wind acclimation in full-size trees. This is an area of enormous importance in understanding how resistance to the wind varies for different species and between areas with different wind climates. In summary, overall much has been learnt since the 1st Wind and Trees conference but there remain many intriguing and exciting challenges ahead for this multi-disciplinary subject.

In forestry, harvest models have become popular for forecasting thinning under business-as-usual scenarios. There are two binary processes involved in thinning operations: (i) whether a plot is to be thinned and (ii) whether a particular tree within that plot is to be harvested. These processes can be modeled using logistic regressions. The data used to fit such models come from forest inventories, where the observations are not usually independent. Random effects can be used to deal with these correlations. However, fitting the plot-level and tree-level models independently hinders the estimation of the covariance between the random effects of both models. The objective of this paper was to develop a statistical method for the simultaneous prediction of harvest probabilities at the plot and tree levels in a single mixed-effects model. We developed a maximum likelihood estimator based on the joint distribution of the probability that a given plot is thinned and the probability that a given tree within that plot is harvested. The estimator was derived from a zero-altered binomial form, but it assumed distinct harvest probabilities for each single tree. The estimator was tested in the case study of mixed stands of oak (Quercus spp.) and beech (Fagus sylvatica L.) in Northern France.

Research into mixed-forests has increased substantially in the last decades but the extent to which the new knowledge generated meets practitioners' concerns and is adequately transmitted to them is unknown. Here we provide the current state of knowledge and future research directions with regards to 10 questions about mixed-forest functioning and management identified and selected by a range of European forest managers during an extensive participatory process. The set of 10 questions were the highest ranked questions from an online prioritization exercise involving 168 managers from 22 different European countries. In general, the topics of major concern for forest managers coincided with the ones that are at the heart of most research projects. They covered important issues related to the management of mixed forests and the role of mixtures for the stability of forests faced with environmental changes and the provision of ecosystem services to society. Our analysis showed that the current scientific knowledge about these questions was rather variable and particularly low for those related to the management of mixed forests over time and the associated costs. We also found that whereas most research projects have sought to evaluate whether mixed forests are more stable or provide more goods and services than monocultures, there is still little information on the underlying mechanisms and trade-offs behind these effects. Similarly, we identified a lack of knowledge on the spatio-temporal scales at which the effects of mixtures on the resistance and adaptability to environmental changes are operating. Our analysis may help researchers to identify what knowledge needs to be better transferred and to better design future research initiatives meeting practitioner's concerns. This article is based upon work from COST Action FP1206, EuMIXFOR, supported by COST (European Cooperation in Science and Technology). The authors want to specially thank the large number of forest managers that were involved in the participatory process and kindly responded to the surveys. The first author also thanks the Spanish Ministry of Economy and Competitiveness for funding the project AGL2015-70425-R which partly supported his contribution to this study. MM acknowledges support by grant IUT21-4 of the Estonian Ministry of Education and Research and DS support by project III 43007 (2011–2017) from Ministry of Education, Science and Technological Development of Republic of Serbia.

Software applications for life cycle assessment of greenhouse gas (GHG) emissions have become popular over the last decade. Their objective is to provide insight into how GHG emissions could be reduced in the sectors defined by the UNFCCC. However, boundaries between these sectors are not closed and current tools are not designed to represent this complexity or to assess the numerous sources of uncertainties. In this paper, we present CAT v1.0, software developed for managed forests in the LULUCF sector, but whose emission life cycle is linked to that of other sectors. While the structure of the software follows IPCC Guidelines, it also contains additional features such as an embedded Monte-Carlo error propagation technique and a user-friendly flux manager that allows for complex cradle-to-grave representations of the wood transformation industry. The flexibility of the software is illustrated through two case studies in northeastern France.

Studying intra-annual growth dynamics through a modelling approach has proved useful for characterizing differences in wood phenology between species and deviations from the expected tree growth due to climate change.The aim of this paper was to determine the climatic factors and the inter-and intra-specific competition traits that drive intra-annual secondary growth dynamics in three Mediterranean tree species that naturally co-exist in the Spanish Northern Plateau (Pinus pinea L., Juniperus thurifera L., and Quercus ilex subsp. ballota (Desf.) Samp.). For this purpose, we obtained girth increment data from band dendrometers installed on 58 trees from May 2012 to April 2015. Half of them were located in a high-density plot and half were in a low-density plot. These data were analysed through a nonlinear multifactorial model considering daily and cumulative climatic effects together with inter-and intra-specific competition indices.Our results provide evidence of a spatiotemporal niche separation between species. Compared with other species, Q. ilex subsp. ballota showed a wider thermal amplitude, a higher mean optimum temperature for growth, and a milder effect of drought on its secondary growth.Under current climate change projections, simulations based on our model predict a secondary growth reduction for P. pinea and a growth enhancement for Q. ilex subsp. ballota in these Mediterranean mixtures.

In forestry, the variable of interest is not always directly available from forest inventories. Consequently, practitioners have to rely on models to obtain predictions of this variable of interest. This context leads to hybrid inference, which is based on both the probability design and the model. Unfortunately, the current analytical hybrid estimators for the variance of the point estimator are mainly based on linear or nonlinear models and their use is limited when the model reaches a high level of complexity. An alternative consists of using a variance estimator based on resampling methods (Rubin, D. B. (1987). Multiple imputation for nonresponse surveys. John Wiley & Sons, Hoboken, New Jersey, USA). However, it turns out that a parametric bootstrap (BS) estimator of the variance can be biased in contexts of hybrid inference. In this study, we designed and tested a corrected BS estimator for the variance of the point estimator, which can easily be implemented as long as all of the stochastic components of the model can be properly simulated. Like previous estimators, this corrected variance estimator also makes it possible to distinguish the contribution of the sampling and the model to the variance of the point estimator. The results of three simulation studies of increasing complexity showed no evidence of bias for this corrected variance estimator, which clearly outperformed the BS variance estimator used in previous studies. Since the implementation of this corrected variance estimator is not much more complicated, we recommend its use in contexts of hybrid inference based on complex models. -- Keywords : Estimator bias; Variance estimator; Estimate of the total; Horvitz-Thompson estimator; Log grade; Lumber recovery model.

International audience; In a recent communication, Cruz et al. (2017) called attention to several recurring statements (mantras) in the wildland fire literature regarding empirical and physical fire behaviour models. Motivated by concern that these mantras have not been fully vetted and are repeated blindly, Cruz et al. (2017) sought to verify five mantras they identify. This is a worthy goal and here we seek to extend the discussion and provide clarification to several confusing aspects of the Cruz et al. (2017) communication. In particular, their treatment of what they call physical models is inconsistent, neglects to reference current research activity focussed on combined experimentation and model development, and misses an opportunity to discuss the potential use of physical models to fire behaviour outside the scope of empirical approaches.

International audience; The conservation and sustainable use of forests in the twenty-first century pose huge challenges for forest management and policy. Society demands that forests provide a wide range of ecosystem services, from timber products, raw materials and renewable energy to sociocultural amenities and habitats for nature conservation. Innovative management and policy approaches need to be developed to meet these often-conflicting demands in a context of environmental change of uncertain magnitude and scale. Genetic diversity is a key component of resilience and adaptability. Overall, forest tree populations are genetically very diverse, conferring them an enormous potential for genetic adaptation via the processes of gene flow and natural selection. Here, we review the main challenges facing our forests in the coming century and focus on how recent progress in genetics can contribute to the development of appropriate practical actions that forest managers and policy makers can adopt to promote forest resilience to climate change. Emerging knowledge will inform and clarify current controversies relating to the choice of appropriate genetic resources for planting, the effect of silvicultural systems and stand tending on adaptive potential and the best ways to harness genetic diversity in breeding and conservation programs. Gaps in our knowledge remain, and we identify where additional information is needed (e.g., the adaptive value of peripheral populations or the genetic determinism of key adaptive traits) and the types of studies that are required to provide this key understanding.

An atypically large outbreak of Elizabethkingia anophelis infections occurred in Wisconsin. Here we show that it was caused by a single strain with thirteen characteristic genomic regions. Strikingly, the outbreak isolates show an accelerated evolutionary rate and an atypical mutational spectrum. Six phylogenetic sub-clusters with distinctive temporal and geographic dynamics are revealed, and their last common ancestor existed approximately one year before the first recognized human infection. Unlike other E. anophelis, the outbreak strain had a disrupted DNA repair mutY gene caused by insertion of an integrative and conjugative element. This genomic change probably contributed to the high evolutionary rate of the outbreak strain and may have increased its adaptability, as many mutations in protein-coding genes occurred during the outbreak. This unique discovery of an outbreak caused by a naturally occurring mutator bacterial pathogen provides a dramatic example of the potential impact of pathogen evolutionary dynamics on infectious disease epidemiology., Elizabethkingia anophelis is an emerging pathogen of high antimicrobial resistance. Perrin and colleagues sequenced isolates of a 2015/2016 E. anophelis outbreak in Wisconsin and found substantial genetic diversity, accelerated evolutionary rate and a disruptive mutation in the DNA repair gene mutY.

Recent studies projecting future climate change impacts on forests mainly consider either the effects of climate change on productivity or on disturbances. However, productivity and disturbances are intrinsically linked because 1) disturbances directly affect forest productivity (e.g. via a reduction in leaf area, growing stock or resource-use efficiency), and 2) disturbance susceptibility is often coupled to a certain development phase of the forest with productivity determining the time a forest is in this specific phase of susceptibility. The objective of this paper is to provide an overview of forest productivity changes in different forest regions in Europe under climate change, and partition these changes into effects induced by climate change alone and by climate change and disturbances. We present projections of climate change impacts on forest productivity from state-of-the-art forest models that dynamically simulate forest productivity and the effects of the main European disturbance agents (fire, storm, insects), driven by the same climate scenario in seven forest case studies along a large climatic gradient throughout Europe. Our study shows that, in most cases, including disturbances in the simulations exaggerate ongoing productivity declines or cancel out productivity gains in response to climate change. In fewer cases, disturbances also increase productivity or buffer climate-change induced productivity losses, e.g. because low severity fires can alleviate resource competition and increase fertilization. Even though our results cannot simply be extrapolated to other types of forests and disturbances, we argue that it is necessary to interpret climate change-induced productivity and disturbance changes jointly to capture the full range of climate change impacts on forests and to plan adaptation measures., published version, peerReviewed

Survival analysis methods make better use of temporal information, accommodate multiple levels of explanatory variables, and are meant to deal with interval-censored data. In a context of harvest modeling, this approach could improve some known limitations. In this study, we used data from a network of permanent plots in the province of Quebec, Canada, as a real-world case study. We tested the potential of survival analysis to predict plot-level harvest probabilities from plot- and regional-level variables. The approach also included random effects to account for spatial correlations.The results showed the potential of survival analysis to provide annual predictions of harvest occurrence. Both regional and time-varying variables, as well as spatial patterns, had important effects on the probability of a plot to be harvested. Respectively, reductions in the annual allowable cut volumes led to a decrease in the harvest probabilities. Greater harvest probabilities were associated with the broadleaved dynamics class and higher values of basal area. In contrast, they were decreased by stem density and slope classes.The spatial random effect resulted in an improvement of the model fit. Our plot- level model improved some limitations reported in previous studies by taking the effect of a time-varying regional variable into account.; Les méthodes d’analyse de survie utilisent mieux l’information temporelle, tiennent compte de multiples niveaux de variables explicatives et sont destinées à traiter des données censurées par intervalle.Dans un contexte de modélisation de la récolte, cette approche pourrait améliorer certaines limites connues. Dans cette étude, nous avons utilisé des données d’un réseau de placettes permanentes de la province de Québec, au Canada, pour servir d’étude de cas concret. Nous avons testé le potentiel de l’analyse de survie pour prédire les probabilités de récolte à l’échelle de la placette, à partir de variables associées à la placette et à la région. L’approche comprenait également des effets aléatoires pour tenir compte des corrélations spatiales.Les résultats ont montré le potentiel de l’analyse de survie pour fournir des prédictions annuelles de l’occurrence de la récolte. Les variables régionales et les variables qui évoluent en fonction du temps, ainsi que la configuration spatiale, avaient des effets importants sur la probabilité qu’une placette soit récoltée. Les réductions de la possibilité annuelle de coupe entraînaient une diminution des probabilités de récolte. Des probabilités de récolte plus grandes étaient associées à la classe de dynamique forestière feuillue et à des valeurs plus élevées de la surface terrière. Inversement, elles étaient diminuées par la densité des tiges et les classes de pente.L’effet aléatoire spatial a entraîné une amélioration de l’ajustement du modèle. Notre modèle à l’échelle de la placette a amélioré certaines limites signalées dans les études précédentes en prenant en compte l’effet d’une variable régionale qui évolue dans le temps.

Wind damage to commercial plantations and natural forests is a serious concern for forest owners and managers all over the world, with notable losses having been reported in the last few decades in Europe, the Americas, and Oceania. Wind-risk models such as ForestGALES allow for a good understanding of the dynamics involved in wind damage, and for calculations of risk to be made, therefore providing vital information on the best practices to minimise such risk. In this paper we parameterise ForestGALES for Eucalyptus globulus (Labill.), arguably one the most widespread and commercially important species for pulp and biomass production, with tree-pulling data obtained in Asturias, Spain. Despite the scarce data on tree and stand characteristics available for wind damaged stands of Eucalyptus spp., we provide an evaluation of our model's performance under different stocking densities by comparing our simulations with real wind damage data acquired from the literature. We show that ForestGALES is able to accurately model the critical wind speeds responsible for Eucalypts stand damage, hence extending the model's applicability to this important commercial genus. In line with good modelling practice, we present the results of a sensitivity analysis of the model, performed with a Global variance-based method. Our sensitivity analysis confirmed the main role of Dbh, stocking density, and tree height in driving the model outputs, and highlighted the importance of accurately knowing the size of any upwind gaps adjacent to a stand to reduce uncertainty in model predictions.

International audience; There is little information about the impacts of past Sitka spruce (Picea sitchensis [Bong.] Carr.) tree breeding on wood properties because the emphasis has traditionally been on improving stem form and growth rates. This study used both SilviScan and mechanical testing to investigate the radial variations in wood stiffness, bending strength, density and microfibril angle in defect-free samples taken from the first United Kingdom progeny trial to reach merchantable size. We tested for differences in these radial patterns of variation in half-sibling progeny of three plus trees originally selected for superior growth rate and stem form against a non-selected control. Large differences in all of the properties were observed with radial position, with properties generally being less desirable in the corewood. Significant undesirable differences between the improved families and the control were found for stiffness, strength and microfibril angle. There was no significant relationship between wood density and stiffness in samples taken from the inner part of the tree, where stiffness was more closely associated with microfibril angle. Overall, previous selections for growth rate and/or stem form have compromised timber properties. It is recommended that current breeding programmes focus on corewood stiffness to prevent further degradation in the wood properties of the future timber supply.

International audience; This paper presents the findings of a Delphi survey, conducted in four European regions (Great Britain, Nordic Region, Central Europe and Iberia) to assess public preferences for 12 key structural attributes of forests. The objectives were to explore the extent to which generalisations can be made about preferences of forests as sites for recreational use, and how regional variations in preferences may be explained in terms of cultural differences in local populations and bio-physical characteristics of the forests in each region. Survey participants were asked to classify the relationship, and quantify the relative importance, of each attribute to the recreational value of forests in their respective regions. While there was agreement across regions on the type of relationship and level of importance for many of the attributes, there were some notable outliers, for example ‘residue from felling and thinning’ scored lowest in Central Europe and highly in the other three regions. Indicative explanations for regional variations are proposed, focusing on combinations of cultural and biophysical factors, and drawing on the literature on forest preferences, place attachment and cultural landscapes.

The primary objective of this report is to assess the current FOREST EUROPE Indicator 6.10 and to make recommendations to improve the reporting of the indicator. The report also considers recreation monitoring to better understand the reasons behind the difficulties in reporting this FOREST EUROPE indicator. The second objective is to identify means to improve monitoring of Indicator 6.10, and assess the use of recreation indicators in selected European countries as a means to identify best practice in terms of a stable standard and quality of measurements, which are comparable across European countries and over time. The report is the result of the work by a small group of experts, mainly researchers, from Finland, Sweden, Denmark, Switzerland, Austria, France and the UK.

A working group was established by the EUFORGEN Steering Committee to develop the pan-European genetic conservation strategy for forest trees. For each species, the strategy calls for a core network of dynamic conservation units. These units are not interconnected by geneflow, but together capture the current genetic diversity across the European continent. Method: The working group selected 14 pilot tree species representing four categories, depending on their geographical distribution (wide vs restricted) and their ecology (stand-forming vs scattered). The group also created a map of eight environmental zones by amalgamating some of the zones of an accepted environmental zoning classification for Europe. It then sought to identify at least one conservation unit per country for each environmental zone in that country, using a set of criteria to determine the most appropriate unit. This process resulted in the identification of 1836 dynamic conservation units, covering a total area of 205,803 ha and encompassing 2173 populations. Gaps in conservation efforts: To identify gaps in existing conservation efforts, the group compared species distribution maps in each environmental zone in each country with the location of the conservation units. Any species with no unit in an appropriate environmental zone in that country was recorded as a gap, and units were also noted where there was an information gap in the EUFGIS database. Genetic Conservation Strategy: The EUFORGEN Steering Committee will promote implementation, identify additional units once gaps have been filled and will monitor progress. A particular concern is the effect of climate change on phenology, but the detailed effects on long-lived tree species are likely to be variable, complex and difficult to predict. As a result, conservation should focus on the most vulnerable populations and species, for example those near the edge of their environmental limits, which often harbour high genetic diversity. Monitoring such populations should help to reveal key changes in a timely fashion, and management may then be needed to mitigate the effects of climate change.

International audience; In order to determine the mechanical resistance of several forest tree species to rockfall, an inventory of the type of damage sustained in an active rockfall corridor was carried out in the French Alps. The diameter, spatial position and type of damage incurred were measured in 423 trees. Only 5% of trees had sustained damage above a height of 1.3 m and in damaged trees, 66% of broken or uprooted trees were conifers. Larger trees were more likely to be wounded or dead than smaller trees, although the size of the wounds was relatively smaller in larger trees. The species with the least proportion of damage through stem breakage, uprooting or wounding was European beech (Fagus sylvatica L.). Winching tests were carried out on two conifer species, Norway spruce (Picea abies L.) and Silver .r (Abies alba Mill.), as well as European beech, in order to verify the hypothesis that beech was highly resistant to rockfall and that conifers were more susceptible to uprooting or stem breakage. Nineteen trees were winched downhill and the force necessary to cause failure was measured. The energy (Efail) required to break or uproot a tree was then calculated. Most .r trees failed in the stem and spruce usually failed through uprooting. Beech was either uprooted or broke in the stem and was twice as resistant to failure as .r, and three times more resistant than spruce. Efail was strongly related to stem diameter in European beech only, and was signi.cantly higher in this species compared to Norway spruce. Results suggest that beech would be a better species to plant with regards to protection against rockfall. Nevertheless, all types of di.erent abiotic stresses on any particular alpine site should be considered by the forest manager, as planting only broadleaf species may compromise the protecting capacity of the forest e.g. in the case of snow avalanches. In order to determine the mechanical resistance of several forest tree species to rockfall, an inventory of the type of damage sustained in an active rockfall corridor was carried out in the French Alps. The diameter, spatial position and type of damage incurred were measured in 423 trees. Only 5% of trees had sustained damage above a height of 1.3 m and in damaged trees, 66% of broken or uprooted trees were conifers. Larger trees were more likely to be wounded or dead than smaller trees, although the size of the wounds was relatively smaller in larger trees. The species with the least proportion of damage through stem breakage, uprooting or wounding was European beech (Fagus sylvatica L.). Winching tests were carried out on two conifer species, Norway spruce (Picea abies L.) and Silver .r (Abies alba Mill.), as well as European beech, in order to verify the hypothesis that beech was highly resistant to rockfall and that conifers were more susceptible to uprooting or stem breakage. Nineteen trees were winched downhill and the force necessary to cause failure was measured. The energy (Efail) required to break or uproot a tree was then calculated. Most .r trees failed in the stem and spruce usually failed through uprooting. Beech was either uprooted or broke in the stem and was twice as resistant to failure as .r, and three times more resistant than spruce. Efail was strongly related to stem diameter in European beech only, and was signi.cantly higher in this species compared to Norway spruce. Results suggest that beech would be a better species to plant with regards to protection against rockfall. Nevertheless, all types of di.erent abiotic stresses on any particular alpine site should be considered by the forest manager, as planting only broadleaf species may compromise the protecting capacity of the forest e.g. in the case of snow avalanches.

Projet co-financé par la commission européenne au sein du sixième programme-cadre (2002-2006). Project n° 518128: EFORWOOD: Tools for Sustainability Impact Assessment Thematic Priority: 6.3 Global Change and Ecosystems; This report describes research carried out to derive scores for the recreational value of 240 forest stand types across Europe. The scores were obtained through a Delphi survey involving 46 European experts organised into 4 regional panels: Great Britain, Nordic Region, Central Europe, and Iberia. In each region, 60 forest stand types were defined according to three tree species types (conifer, broadleaved, and mixed), four phases of development (i.e. stand ages: establishment, young, medium and adult), and five forest management alternatives (FMAs) on a continuum from low to high levels of management intensity (forest nature reserves, close-to-nature forests, combined-objective forestry, intensive even-aged forestry, and wood biomass production). The resulting scores were applied in two ways. First, they were combined with outputs from the European forest resource projection model, EFISCEN, to estimate current and future recreational values under different policy scenarios. This is reported in EFORWOOD D2.3.7. Secondly, which is the focus of this report, conjoint analysis was used to determine, in each European region, the relative importance of the three variables that defined the forest stand types: type of tree species, phase of development (i.e. stand age), and FMA. The research complements EFORWOOD D2.3.3 which used other data derived from the same Delphi survey to assess the nature, and relative importance, of the relationship between 12 key silvicultural attributes and the recreational value of forests in each of the four regions. The findings suggest that, across Europe, tree species composition was of relatively minor importance in explaining the overall variation in scores. In UK and Central Europe, comparably high importance was attached to FMA and phase of development, while in the Nordic Region and Iberia, phase of development was considered more important than FMA. The relative importance attached to each FMA suggests that most visitors prefer close-to-nature or combined-objective forestry to unmanaged forest nature reserves. The low importance attached to tree species suggest that criticism directed towards non-native conifers, and perceived preferences for broadleaves across Europe, may not be due to the choice of tree species per se, but the use of conifers in intensive management regimes characterized by dense even-aged monocultures and short rotation lengths. It is acknowledged that such a finding may hide substantial variation in preferences between individuals and social groups, between people pursuing different recreational activities, and between geographical regions with their contrasting cultural landscapes.

Projet co-financé par la commission européenne au sein du sixième programme-cadre (2002-2006). Project n° 518128: EFORWOOD: Tools for Sustainability Impact Assessment Thematic Priority: 6.3 Global Change and Ecosystems; This report demonstrates the application of recreational scores, obtained through a pan-European Delphi survey as part of EFORWOOD, to model the impacts of changes in forest management on the recreational value of European forests. Changes in the level of implementation of the Natura 2000 policy is used as an example. Currently, about 8% of the EU forest area is allocated to biodiversity conservation (MCPFE class 1; MCPFE 2007). According to the Natura 2000 Agenda, 15% of the territory of the EU should be designated as conservation area by 2025. It is to be expected, therefore, that the forest conservation area will increase considerably in the near future. The impact of different nature conservation implementation levels on the recreational value of forests in Europe was explored using recreational scores derived from the Delphi survey, and combined with outputs from the forest scenario model EFISCEN. Changes in recreational value were considered against two background futures (A1 and B2 from the SRES scenarios) and three different nature conservation implementation levels. The results suggest that overall an increase in forest area managed for conservation would cause a slight net increase the recreational value per hectare of forests in Europe, although there is considerable variation between countries.

International audience; & Context A strategy widely proposed for increasing the resil-ience of forests against the impacts of projected climate change is to increase the number of species planted to spread and reduce the risks from a range of biotic and abiotic hazards. & Aims We tested this strategy in two case study areas in planted conifer forests in New Zealand and Scotland. & Methods The performance of the major tree species and an alternative was compared: radiata pine and Eucalyptus fastigata in New Zealand and Sitka spruce and Scots pine in Scotland. The process-based model 3-PG2S was used to simulate the effects of projected climate change at the end of this century, with and without CO 2 fertilisation, upon pro-ductivity and financial returns. The effects of an abiotic hazard and two biotic hazards were considered. & Results Under the current climate, the major species outperform alternatives in nearly all circumstances. However, with climate change, their relative performance alters. In New Zealand, planting of E. fastigata becomes more attractive particularly when various hazards and elevated CO 2 concen-trations are considered. In Scotland, Scots pine becomes more attractive than Sitka spruce at lower interest rates. & Conclusions The major plantation species in both coun-tries are well suited to the current climate, but deployment of alternative species and/or breeds can help to adapt these planted forests to the impacts of climate change.

International audience; Because wood density is an important indicator of the end-use mechanical properties of sawn timber, detailed knowledge of its variation is important for optimizing value in processing. The aim of this study was to develop a model for predicting wood density variation in plantation-grown Scots pine (Pinus sylvestris L.) using position in the stem and radial growth increment as independent variables. Seventy trees, ranging in age at 1.3 m from 9 to 99 years, were sampled from 12 even-aged Scots pine stands in Scotland, UK. Pith-to-bark density profiles were obtained on 193 radial samples using scanning X-ray densitometry. We developed a mixed-effects model of average ring density (expressed as basic specific gravity) based on an exponential function of cambial age, height along the stem and annual ring width. Basic specific gravity ranged from 0.274 to 0.697, with a mean of 0.423, and increased rapidly from the pith until approximately rings 20–30, before stabilizing. In addition, there was a weak negative relationship between basic specific gravity and annual ring width, and for a given cambial age, basic specific gravity decreased with sampling height. The fixed effects of the final model were able to explain ∼57 per cent of the within-stem variation in wood density (78 per cent if random effects were included). The final model is intended for integration into a growth, yield and wood quality simulation system.

International audience; Gene flow is a key factor in the evolution of species, influencing effective population size, hybridisation and local adaptation. We analysed local gene flow in eight stands of white oak (mostly Quercus petraea and Q. robur, but also Q. pubescens and Q. faginea) distributed across Europe. Adult trees within a given area in each stand were exhaustively sampled (range [239, 754], mean 423), mapped, and acorns were collected ([17,147], 51) from several mother trees ([3], [47], 23). Seedlings ([65,387], 178) were harvested and geo-referenced in six of the eight stands. Genetic information was obtained from screening distinct molecular markers spread across the genome, genotyping each tree, acorn or seedling. All samples were thus genotyped at 5–8 nuclear microsatellite loci. Fathers/parents were assigned to acorns and seedlings using likelihood methods. Mating success of male and female parents, pollen and seed dispersal curves, and also hybridisation rates were estimated in each stand and compared on a continental scale. On average, the percentage of the wind-borne pollen from outside the stand was 60%, with large variation among stands (21–88%). Mean seed immigration into the stand was 40%, a high value for oaks that are generally considered to have limited seed dispersal. However, this estimate varied greatly among stands (20–66%). Gene flow was mostly intraspecific, with large variation, as some trees and stands showed particularly high rates of hybridisation. Our results show that mating success was unevenly distributed among trees. The high levels of gene flow suggest that geographically remote oak stands are unlikely to be genetically isolated, questioning the static definition of gene reserves and seed stands.

International audience; Dynamic conservation of forest genetic resources (FGR) means maintaining the genetic diversity of trees within an evolutionary process and allowing generation turnover in the forest. We assessed the network of forests areas managed for the dynamic conservation of FGR (conservation units) across Europe (33 countries). On the basis of information available in the European Information System on FGR (EUFGIS Portal), species distribution maps, and environmental stratification of the continent, we developed ecogeographic indicators, a marginality index, and demographic indicators to assess and monitor forest conservation efforts. The pan-European network has 1967 conservation units, 2737 populations of target trees, and 86 species of target trees. We detected a poor coincidence between FGR conservation and other biodiversity conservation objectives within this network. We identified 2 complementary strategies: a species-oriented strategy in which national conservation networks are specifically designed for key target species and a site-oriented strategy in which multiple-target units include so-called secondary species conserved within a few sites. The network is highly unbalanced in terms of species representation, and 7 key target species are conserved in 60% of the conservation units. We performed specific gap analyses for 11 tree species, including assessment of ecogeographic, demographic, and genetic criteria. For each species, we identified gaps, particularly in the marginal parts of their distribution range, and found multiple redundant conservation units in other areas. The Mediterranean forests and to a lesser extent the boreal forests are underrepresented. Monitoring the conservation efficiency of each unit remains challenging; however

International audience; Adaptation of forest management practices in the context of rapid climatic and socioeconomic changes is a global concern. Stakeholders in the forest-based sector as well as policy makers need improved methods and tools to assess potential impacts of changes in management on sustainability indicators. In this special feature, we introduce a methodological framework for classification of forest management approaches in European forestry and explore how changes in forest management might affect the delivery of various ecosystem goods and services and appropriate sustainability indicators over time and space from local to continental scales. The complementary papers in this special feature explore different aspects of sustainability and risks in representative European forest systems as affected by forest management. We show how a common framework plus supporting growth models and indicators can be used to examine the effects of management on ecosystem services and so provide a first step toward the development of a more integrated approach for strategic forest planning and sustainable use of forest ecosystems.

International audience; Due to climate change, forests are likely to face new hazards, which may require adaptation of our existing silvicultural practices. However, it is difficult to imagine a forest management approach that can simultaneously minimize all risks of damage. Multicriteria decision analysis (MCDA) has been developed to help decision makers choose between actions that require reaching a compromise among criteria of different weights. We adapted this method and produced a multicriteria risk analysis (MCRA) to compare the risk of damage associated with various forest management systems with a range of management intensity. The objective was to evaluate the effect of four forest management alternatives (FMAs) (i.e., close to nature, extensive management with combined objectives, intensive even-aged plantations, and short-rotation forestry for biomass production) on biotic and abiotic risks of damage in eight regional case studies combining three forest biomes (Boreal, Continental, Atlantic) and five tree species ( Eucalyptus globulus, Pinus pinaster, Pinus sylvestris, Picea sitchensis, and Picea abies) relevant to wood production in Europe. Specific forest susceptibility to a series of abiotic (wind, fire, and snow) and biotic (insect pests, pathogenic fungi, and mammal herbivores) hazards were defined by expert panels and subsequently weighted by corresponding likelihood. The PROMETHEE ranking method was applied to rank the FMAs from the most to the least at risk. Overall, risk was lower in short-rotation forests designed to produce wood biomass, because of the reduced stand susceptibility to the most damaging hazards. At the opposite end of the management intensity gradient, close-to-nature systems also had low overall risk, due to lower stand value exposed to damage. Intensive even-aged forestry appeared to be subject to the greatest risk, irrespective of tree species and bioclimatic zone. These results seem to be robust as no significant differences in relative ranking of the four FMAs were detected between the combinations of forest biomes and tree species.

International audience; Until recently Phytophthora lateralis was known only as the cause of dieback and mortality of Chamaecyparis lawsoniana in its native range in the Pacific Northwest (PNW). Since the 1990s however disease outbreaks have occurred increasingly on ornamental C. lawsoniana in Europe; and in 2007 the pathogen was discovered in soil around old growth Chamaecyparis obtusa in Taiwan, where it may be endemic. When the phenotypes of over 150 isolates of P. lateralis from Taiwan, across the PNW (British Columbia to California) and from France, the Netherlands and the UK were compared three growth rate groups were resolved: one slow growing from Taiwan, one fast growing from the PNW and Europe, and one of intermediate growth from a small area of the UK. Within these growth groups distinct subtypes were identified based on colony patterns and spore metrics and further discriminated in a multivariate analysis. The assumption that the three main growth groups represented phylogenetic units was tested by comparative sequencing of two mitochondrial and three nuclear genes. This assumption was confirmed. In addition two phenotype clusters within the Taiwan growth group were also shown to be phylogenetically distinct. These four phenotypically and genotypically unique populations are informally designated as the PNW lineage, the UK lineage, the Taiwan J lineage, and the Taiwan K lineage. Their characteristics and distribution are described and their evolution, taxonomic, and plant health significance is discussed.

This article documents the addition of 299 microsatellite marker loci and nine pairs of single-nucleotide polymorphism (SNP) EPIC primers to the Molecular Ecology Resources (MER) Database. Loci were developed for the following species: Alosa pseudoharengus, Alosa aestivalis, Aphis spiraecola, Argopecten purpuratus, Coreoleuciscus splendidus, Garra gotyla, Hippodamia convergens, Linnaea borealis,Menippe mercenaria,Menippe adina, Parus major, Pinus densiflora, Portunus trituberculatus, Procontarinia mangiferae, Rhynchophorus ferrugineus, Schizothorax richardsonii, Scophthalmus rhombus, Tetraponera aethiops, Thaumetopoea pityocampa, Tuta absoluta and Ugni molinae. These loci were cross-tested on the following species: Barilius bendelisis, Chiromantes haematocheir, Eriocheir sinensis, Eucalyptus camaldulensis, Eucalyptus cladocalix, Eucalyptus globulus, Garra litaninsis vishwanath, Garra para lissorhynchus, Guindilla trinervis, Hemigrapsus sanguineus, Luma chequen. Guayaba, Myrceugenia colchagu¨ensis, Myrceugenia correifolia, Myrceugenia exsucca, Parasesarma plicatum, Parus major, Portunus pelagicus, Psidium guayaba, Schizothorax richardsonii, Scophthalmus maximus, Tetraponera latifrons, Thaumetopoea bonjeani, Thaumetopoea ispartensis, Thaumetopoea libanotica, Thaumetopoea pinivora, Thaumetopoea pityocampa ena clade, Thaumetopoea solitaria, Thaumetopoea wilkinsoni and Tor putitora. This article also documents the addition of nine EPIC primer pairs for Euphaea decorata, Euphaea formosa, Euphaea ornata and Euphaea yayeyamana.

International audience

Projet PCRD, EFORWOOD, Sustainability impact assessment of the forestry-wood chain; Instrument: IPThematic Priority: 6.3 Global Change and Ecosystems; This deliverable presents the research protocol for the Delphi survey that is being used to derive scoresto assess the recreational value of 240 forest stand types in four European regions: upland areas ofGreat Britain, Boreal areas of the Nordic Region, Central Europe, and Mediterranean areas of Iberia.The scores will contribute to a European synthesis of public perceptions of the recreational value offorests (EFORWOOD D2.3.3 and D2.3.6). They will also be combined with outputs from theEuropean forest resource projection model, „EFISCEN‟, to estimate current and future recreationalvalues under different scenarios (EFORWOOD D2.3.7). A concluding section outlines the timing ofthe survey and final steps for the WP2.3 research agenda. The questionnaire used for the Great Britainsurvey is included as an appendix.

Storm Damage and Classification • More than 130 separate wind storms have been identified as causing noticeable damage to European forests in the last 60 years (~2/year). • Storms are responsible for more than 50% of all primary abiotic and biotic damage by volume to European forests from catastrophic events. • Storm damage is categorized in this report into 3 components: o Primary damage: Initial mechanical damage to the trees caused by the storm o Secondary damage: Subsequent damage following the initial wind storm. This is mostly from bark beetles, but can be from other biotic factors, fire, sun, snow/ice and even additional wind damage. o Tertiary damage: Loss of production in shortened forest rotations and other long-term constraints on forest operations • A proposed storm classification has been developed based on the percentage of growing stock (%GS) initially damaged (primary damage) by the storm. • 11 Storms (January 1953, September 1967, September 1969, November 1972, October 1987, January-March 1990, December 1999, November 2004, January 2005, January 2007, January 2009) were selected for study in greater detail. • An extensive database of storms; and a more detailed database for the 11 specific storms have been created. These are available online at: http://www.efiatlantic.efi.int/portal/databases/European_storms_catalogue Contributing Factors • The amount and location of storm damage and the vulnerability of forest stands is a complex interaction between the meteorological conditions and stand location, soil type, stand composition, and past forest management. • The evidence for the impacts of certain forest operations, species choices or site conditions is often weak, missing or contradictory. Therefore, we have only made statements when there is clear scientific evidence to support these statements. • Gust peak wind speed is strongly correlated to the maximum potential levels of damage: o No appreciable damage for gust peak wind speeds below 30 ms-1 o Moderate levels of damage (maximum damage up to 2% of national growing stock) for gust peak wind speeds between 30 ms-1 and 40 ms-1 o High levels of damage (maximum potential damage between 2 - 4% of national growing stock) for gust peak wind speeds between 40 ms-1 and 45 ms-1 o Severe levels of damage (maximum potential damage > 4% of national growing stock) for gust wind speeds above 45 ms-1. • Tree height has an important impact on vulnerability. • Statistical analysis of storm damage suggests that spruces and poplar are among the most vulnerable and silver fir and oak among the least vulnerable respectively of the conifers and broadleaves. However, such differences, and 5 the generally higher susceptibility of conifers to damage, are confounded by differences in species management and the choice of sites on which they are planted. • Soil condition is very important. Root anchorage strength is increased by soil freezing, and reduced by water-logging and heavy rain and by poor drainage that allows soil saturation during storms. • Recent thinning, particularly in older stands, is often associated with increased damage. • The vertical structure of stands (e.g. irregular versus regular) appears to have little influence on stability. • Taking any site or stand factor in isolation as a way of assessing vulnerability and/or risk of a forest can be completely misleading. Current and Future Trends • The increase of growing stock and average forest age across Europe in the last 60 years has contributed to the increase of observed damage. • If the total growing stock and average age of European forests continues to increase there will be a proportional increase in the volume of storm damaged trees. • There is some evidence that storm intensity is increasing and that storm tracks are penetrating further into mainland Europe and along a wider swathe, increasing the risk to forests in Eastern Europe. • With climate change, higher temperatures will lead to longer periods of unfrozen soils during European winters, potentially leading to an increase in damage particularly in Fennoscandia. • Storms will tend to be accompanied by heavier rainfall leading to more saturated soils and increased risk of wind damage. • If the current build-up of growing stock continues together with predicted changes to the climate, damage levels are expected to at least double, and possibly quadruple, by the end of the century. • Best current estimates suggest that storm damage to European forests results in an annual reduction of 2% in the carbon sequestration by forests. This figure could exceed 5% by the end of the century if the current build-up of growing stock continues. Existing Responses to Storms • There is no consistent recording and reporting system for wind damage across Europe or for reporting damage from different hazards (abiotic and biotic). This leads to uncertainties in relative levels of wind damage within different parts of Europe and in assessing the importance of specific hazards. • There is a large amount of information and knowledge within Europe on the causes of forest storm damage and the best methods for dealing with their aftermath. However, this information is widely dispersed, is often out-of-date and may only be available in certain languages. • Most countries in Europe affected by storm damage to forests respond in a similar manner. This includes providing subsidies for harvesting, transport and 6 forest restoration, the short-term derogation of controls, and the production of guidelines on the best methods to re-establish or regenerate the storm affected forests. The similarity in approaches makes the production of a European wide set of generic advice, best practice guidelines and policy instruments a possibility.

Projet co-financé par la commission européenne au sein du sixième programme-cadre (2002-2006). Project n° 518128: EFORWOOD: Tools for Sustainability Impact Assessment Thematic Priority: 6.3 Global Change and Ecosystems ; This report explores the relationship and contribution of 12 key silvicultural attributes to the recreational value of forests in Europe. While the majority of research in this field has focused on individual case studies, this study is one of the few to provide a pan-European synthesis through a combination of a literature review and primary research. A Delphi survey was carried out with panels of experts in each of four contrasting European regions: Great Britain, the Nordic Region, Central Europe, and Iberia. For each attribute, participants were asked to state what they believed to be the nature of the relationship, and relative contribution, of each attribute to the overall recreational value of forests. The findings indicate that 'size of trees' is universally considered one of the most important attributes, along with attributes that reflect level of intervention such as 'size of clear-cuts', 'residue from thinning and harvesting', and 'visual penetration'. The results also suggest that, on average, the public prefer a degree of intervention to 'tidy up' the forest, creating a situation of 'managed naturalness'. Other key findings include the relative unimportance of 'number of tree species'. There are also some striking variations in the ranking of certain attributes across regions. 'Residue' is considered of very little importance in Central Europe whereas it scores highly elsewhere. Similarly, in Great Britain, the highest importance is attached to 'variation in tree size', although this attribute scores low elsewhere. The low importance given to 'variation between stands' in Great Britain contrasts with the Nordic Region and Central Europe, where, arguably, similar kinds of forest may extend across large areas and may be seen to be monotonous.

International audience; This book is designed to assist the civil and geotechnical engineer, geomorphologist, forester, landscape architect or ecologist in choosing ecotechnological solutions for slopes that are prone to a variety of mass movements e.g. shallow failure or erosion. Within this book, the ‘engineer’ is used in the global sense to encompass all planners, designers, etc who are involved in the stabilisation of slopes. We review the types of problematic slopes that may occur and describe briefly the nature of mass movements and the causes of these movements. In this book, we focus on the use of vegetation to stabilize soil on slopes prone to mass movements. Before a plant can be chosen for a particular function, its physical and hydrological properties must be determined, thus the root architecture of grasses, shrubs and trees are described and the soil hydrological and mechanical factors which influence vegetation are discussed. Depending on the use of the slope, the engineer may wish to ascertain either the stability of the slope or the mechanical stability of the vegetation or both, therefore slope stability analysis methods are reviewed and the contribution the vegetation has to the stability of the slope are explained. Models to assess the mechanical stability of vegetation are reviewed. This book also introduces new ecotechnological methods for stabilising active rockfalls on steep slopes and slopes that are prone to soil erosion following wild fires, as well as providing user friendly information on traditional ground bio-engineering techniques and tables of plants suitable for different functions. Case studies where ground bio- and eco-engineering measures have been put into practice are also discussed

International audience; A model was developed that simulated photosynthesis, growth and allocation in tree seedlings. The model was parameterized with data from experiments on seedlings of sycamore (Acer pseudoplatanus L.), Sitka spruce (Picea sitchensis (Bong) Carr.) and young birch trees (Betula pendula Roth.). In these experiments, CO2 concentration ([CO2]) and nutrient addition rate were varied. Parameters quantifying nutrient uptake, translocation and starch synthesis were fitted, bared on data from control treatments. Elevated [CO2] and low-nutrient treatments were then used to test the predicted response of growth and allocation against observations. The model accurately predicted total seedling growth in the elevated [CO2] treatments. A response of growth to elevated [CO2] was seen in the birch and sycamore experiments, but not in the Sitka spruce, because of photosynthetic down-regulation. Predictions of allocation were reasonably accurate in the birch and Sitka spruce experiments, but were notably poorer in the sycamore experiments, possibly because of differences in sink strength between root and shoot. In the birch and sycamore experiments, little change in allocation with elevated [CO2] was observed or predicted. This was ascribed to the relative values of K-Tc and K-Tn, the translocation coefficients that determine the sensitivity of allocation to carbon and nitrogen uptake rates, respectively. Growth and allocation in the low-nutrient treatments were poorly predicted by the model. In Sitka spruce, it was suspected that the photosynthetic parameters measured in August 1994 had been higher earlier in the season, before nutrients became depleted. In sycamore, the discrepancies were thought to relate to differences in sink strength between root and shoot that could not be described by the model.

Predicting the probability of wind damage in both natural and managed forests is important for understanding forest ecosystem functioning, the environmental impact of storms and for forest risk management. We undertook a thorough validation of three versions of the hybrid-mechanistic wind risk model, ForestGALES, and a statistical logistic regression model, against observed damage in a Scottish upland conifer forest following a major storm. Statistical analysis demonstrated that increasing tree height and local wind speed during the storm were the main factors associated with increased damage levels. All models provided acceptable discrimination between damaged and undamaged forest stands but there were trade-offs between the accuracy of the mechanistic models and model bias. The two versions of the mechanistic model with the lowest bias gave very comparable overall results at the forest scale and could form part of a decision support system for managing forest wind damage risk. Comprehensive description and validation of three versions of a mechanistic wind risk model for even-aged forests.Analysis of the performance of mechanistic and logistic regression models against measured damage in a conifer forest.All models provided acceptable discrimination between damaged and undamaged forest stands.The two version of the mechanistic model with the lowest bias gave very comparable overall results at the forest scale.Statistical analysis showed that increasing tree height and local wind speed were the main factors associated with damage.