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A presentation of the measurement of the activity of water was carried out among a group of experts and scientists of the Tree Seed Working Group of the Canadian Tree Improvement Association at the time of the visit of the installations of the Seed Centre of Berthier within the framework of the pre-turn of joint congress IUFRO-ACAA/CTIA 2008 in Quebec. During a demonstration we presented the theoretical and operational aspects of the measurement of the activity of water in the laboratory of the only centre of forest seeds of Quebec which recently adopted this method for seeds and pollens management. The simplicity and the speed of acquisition of measurement as well as the non-destructive character of the procedure were underlined in particular., Une présentation de la mesure de l'activité de l'eau a été réalisée auprès d'un groupe de praticiens et de scientifiques du Tree Seed Working Group de l'Association Canadienne d'Améliorateurs forestiers lors de la visite des installations du centre de semences de Berthier dans le cadre du pré-tour du congrès IUFRO-ACAA 2008 à Québec. Ont été présentés les aspects théoriques et opérationnels de la mesure de l'activité de l'eau lors d'une démonstration dans le laboratoire du seul centre de semences forestières du Québec qui a récemment adopté cette méthode de contrôle des semnces et pollens. La simplicité et la rapidité d'acquisition de la mesure ainsi que le caractère non destructif de la procédure ont été soulignés en particulier.

The unknown males of Bocchus italicus Olmi, B. umber Olmi and B. vernieri Olmi are described, as is the macropterous female of B. vernieri, previously known only from brachyptreous female. revised keys to the European species of the genus Bocchus Ashmead are provided., Description des males inconnus de Bocchus italicus Olmi, B. umber Olmi et B. vernieri Olmi, ainsi que de la femelle macroptère de B. vernieri, auparavant connue seulement de la forme brachyptère. Une clé révisée des espèces européennes du genre Bocchus Ashmead est donnée.

L'ingénierie écologique est une notion qui date de plusieurs décennies, à la fois dans la sphère scientifique et, en France, dans la gestion. Elle semble néanmoins monter en puissance depuis quelques années, sous forme de discipline académique, et dans les discours des scientifiques. Après avoir résumé les propos de Barbault et Pavé (2003) expliquant cet état de fait, l'auteur propose une définition de l'ingénierie écologique qui soit compatible avec les deux déterminants principaux qui justifient sa ré-émergence : la notion de développement durable, et les disciplines appliquées de l'écologie. L'auteur précise ensuite certains des problèmes et caractéristiques associés à cette définition de l'ingénierie écologique / Ecological engineering was defined several decades ago, both in the academic field and in management. However, ecological engineering seems to be re-emerging as an academic field and as a cornerstone concept in French ecologists' writings. I first summarize Barbault and Pave's [Barbault, R., Pave?, A., 2003. Territoire de l'e?cologie et ecologie des territoires. In: Caseau, P. (Ed.), Etudes sur l'environnement: de l'e?chelle du territoire a celle du continent, Tec et Doc Lavoisier, Paris, pp. 1-49] point of view on why ecological engineering now seems rehabilitated in France. I next propose a definition of ecological engineering, in accordance with the two reasons for its French re-emergence, i.e. the prevalence of the concept of sustainable development and the development of applied ecological sub-disciplines. This leads us to suggest that ecological engineering should be ecological in the broad sense, and not only targeted to the ecosystem level. I end the paper by discussing some problems and characteristics of ecological engineering that stem from this definition.

International audience; This paper is the outcome of a group discussion held at the Savonlinna meeting Management of forest ecosystems and its impact on the GHG budget'. The aim of this break-out group discussion was to Characterize forest management impacts on the GHG budget of forest ecosystems in different European regions'. In this paper we briefly characterize different options that a forest owner has in order to maintain or maximize forest carbon pools and carbon sequestration. These hectare scale descriptions of measures are then regarded in connection to the current state of European forests and how they can be combined with ongoing management trends and local issues. We point out the various possibilities that exist in European forests, where they are located, and where they could possibly be combined with adaptation. We identify these hotspots for largest growing stocks, largest peat areas, and, e.g. largest risks for loss of carbon due to fire or urban sprawl. We conclude that one common strategy cannot be designed. Within each region, local solutions have to be found that optimize goals and aim at integrated and sustainable land use.

Many studies on carabid ecology rely on the comparison of carabid assemblages among various habitat types, assuming that pitfall trap catches are not biased by the environmental conditions. However, some authors have already suspected that the structure of the vegetation surrounding pitfall traps may have an impact on the trapping efficiency by modifying carabid movements, either through a barrier effect of ground-vegetation or though micro-climatic conditions influencing beetle activity. Therefore, we wonder whether there might be a strong bias in capturability of carabid species between habitat types: does capture probability of carabid species strongly vary with canopy-closure degree in forest stands ? Without real capture-marked-recapture experiments of individuals, a probability of capture for a set of species can yet be estimated by using spatially-repeated measures of carabid assemblages, thanks to probabilistic methods coming from capture-mark-recapture theoretical models applied to community ecology. Thus, to evaluate the difference in capture probability between various habitat types, we analysed a carabid data set of 28 plots of different forest stages within a French temperate oak forest (Montargis state forest, 4000 ha). In each plot, 4 traps, half-filled with a solution of 50% ethylene-glycol, were arranged in the four corners of a 14 m x 14 m square and were activated during 3 one-week periods in late spring and late summer. The canopy-closure degree of the silvicultural stage modified the form of the species rarefaction curves from a 1-plot-by-stage strategy to a n-plot-by-stage strategy (n varying from 4 to 8 plots) : the seeding cuts seemed to be less exhaustively sampled than the other stages. However, as capture probabilities, estimated and compared using COMDYN program, did not significantly differ between silvicultural stages (Chi-square tests), the comparison of carabid species richness at the stage scale does not seem to be biased by the canopy-closure degree of the stage.

International audience; Beech woodland can be restored by direct planting of beech (Fagus sylvatica L.) seedlings in abandoned areas, but this method is generally avoided in forestry because of the growth difficulties of beech in full light conditions. This study tested a method that consists in planting beech seedlings in full-light conditions with Silver birch or Scots pine as nurse trees. A total of 65 two-year-old beech seedlings surrounded by either 3, 4, 5 or 6 pine or birch seedlings or without competitors were planted in bare-soil open-field conditions in central France. Tree growth and light availability were monitored at the end of each of the 3 years, and soil moisture was also measured the last year. At the end of the experiment, aerial biomass measurements were made on the beeches. Results showed that relative beech growth in terms of diameter was reduced by the local neighbourhood and that this reduction was particularly noticeable in the pine treatments where there was extensive pine seedling development. In contrast, relative beech height did not exhibit any significant variations among the treatments. Light availability was decreased by the neighbourhood, especially in the pine treatments. Light reduction was more pronounced in the last two years and in the middle or lower parts of the canopy of the subject beech. Soil water content was lower under the pine canopies than under the birch canopies, and was positively correlated to beech relative diameter growth. SLA, height-to-diameter ratio and crown length-to-crown width ratio increased with increasing competition from the neighbours. There were treatment effects on beech biomass partitioning: the branch biomass-to-total biomass ratio was lower in the pine treatment than in the birch treatment, whereas stem-to-total biomass ratio was lower in the birch treatment. This study showed that nurse trees tend to reduce beech growth but improve form. However, further studies are needed to quantify the effects of the neighbourhood on the growth of competitive herbaceous vegetation and on changes in the microclimatic conditions.

Growth and survival of regeneration saplings and understorey vegetation development is closely related to light available below the forest trees. Manipulating the forest structure by thinning adult trees is a major tool to control light transmission to the understorey. The transmission is related to the attenuation of light which is usually estimated with the Beer-Lambert law assuming homogeneous foliage within the canopy. However forest canopies are far from homogeneous, which requires models that can take into account the effect of clumping between and within trees. In this work we present a model that can be readily used with both coarse or detailed parameterization to generate any type of stand and compute the distribution of light transmitted below the canopy. To evaluate the accuracy of the model, we compared model results with field measurements from several stands of Pinus sylvestris L. in the French Massif Central.

Many studies on carabid ecology rely on the comparison of carabid assemblages among various habitat types, assuming that pitfall trap catches are not biased by the environmental conditions. However, some authors have already suspected that the structure of the vegetation surrounding pitfall traps may have an impact on the trapping efficiency by modifying carabid movements, either through a barrier effect of ground-vegetation or though micro-climatic conditions influencing beetle activity. Therefore, we wonder whether there might be a strong bias in capturability of carabid species between habitat types: does capture probability of carabid species strongly vary with canopy-closure degree in forest stands ? Without real capture-marked-recapture experiments of individuals, a probability of capture for a set of species can yet be estimated by using spatially-repeated measures of carabid assemblages, thanks to probabilistic methods coming from capture-mark-recapture theoretical models applied to community ecology. Thus, to evaluate the difference in capture probability between various habitat types, we analysed a carabid data set of 28 plots of different forest stages within a French temperate oak forest (Montargis state forest, 4000 ha). In each plot, 4 traps, half-filled with a solution of 50% ethylene-glycol, were arranged in the four corners of a 14 m x 14 m square and were activated during 3 one-week periods in late spring and late summer. The canopy-closure degree of the silvicultural stage modified the form of the species rarefaction curves from a 1-plot-by-stage strategy to a n-plot-by-stage strategy (n varying from 4 to 8 plots) : the seeding cuts seemed to be less exhaustively sampled than the other stages. However, as capture probabilities, estimated and compared using COMDYN program, did not significantly differ between silvicultural stages (Chi-square tests), the comparison of carabid species richness at the stage scale does not seem to be biased by the canopy-closure degree of the stage.

Poster presenting BiodivSamp start-up project that aimed at optimising sampling strategies for biodiversity monitoring., Poster présentant l'initiative BiodivSamp, projet interne d'ALTER-Net qui visait à optimiser les stratégies d'échantillonnage pour le suivi de la biodiversité.

Population Viability Analysis often relies on population dynamics models. In particular extinction models aim at quantifying the risk of extinction of populations subject of conservation concerns. Many such models are developed as simulation models, although the behaviour of stochastic models incorporating various types of variability (such as demographic and environmental stochasticity) can be complex and difficult to analyse. We present here, based on a simple example, a large class of stochastic models, branching processes. We summarize their key explicit mathematical properties as extinctions models, in particular, in conditions realistic for conservation biology, the so-called quasi-stationarity (certainty of extinction, existence of stationary distribution of population size conditional on non extinction, geometric distribution of time to extinction). Quasi-stationarity links on a continuum of annual extinction probability decreasing populations and populations stabilized by density-dependence. We develop then approximations of the annual probability of extinction and illustrate them about the Amsterdam Albatross Diomedea amsterdamensis, a critically endangered species. Extinction models being clearly more useful for hierarchizing risks of extinction rather than for estimating in an absolute fashion a probability of extinction, we hope our approach will open the way to sensitivity analyses of the risk of extinction., L'analyse de Viabilité des Populations s'appuie fréquemment sur des modèles de dynamique des populations. En particulier les modèles d'extinction visent à quantifier le risque d'extinction de populations posant des problèmes de conservation. Beaucoup de tels modèles sont développés comme modèles de simulation, alors que le comportement de modèles stochastiques complexes, incorporant par exemple stochasticité démographique et environnementale, peut être complexe et d'analyse difficile. Nous présentons ici à l'aide d'un exemple simple, une large classe de stochastiques modèles, les processus de ramification. Nous résumons leurs propriétés mathématiques clés, en particulier, dans des conditions réalistes pour l'écologie de la conservation, la quasi-stationnarité (certitude de l'extinction, existence d'une distribution stationnaire conditionnelle à la non-extinction, distribution géométrique de la date d'extinction). La quasi-stationnarité relie sur un continuum de probabilité d'extinction annuelle populations décroissantes et stabilisées par densité-dependance. Nous développons ensuite des approximations de la probabilité annuelle d'extinction, illustrées à propos de l'Albatros d'Amsterdam Diomedea amsterdamensis, une espèce en danger critique. Les modèles d'extinction étant clairemnt plus utiles pour hiérarchiser des risques que pour évaluer de façon absolue des probabilités d'extinction, nous espérons que notre approche ouvrira la voie à des analyses de sensibilité des risques d'extinction.

[Departement_IRSTEA]GT [TR1_IRSTEA]SET / BIOFOR; A new parametric structural leaf model and its automatic instantiation from 3D digitized data is exposed. The proposed model allows representing the morphological features of a wide range of leaves into a controlled number of morphological parameters defining the accuracy of the 3D leaf representation. Using a set of suitable leaf-related geometrical hypothesis, these values are automatically inferred from dense digitized data provided by a non-contact digitizer Konica Minolta vi-910. A quantitative assessment, based on an inversion algorithm allowing building a tessellated leaf model from a prescribed set of parameters, demonstrates the reliability of both the model parameters and the instantiation process. An application to light interception computation via the software VegeSTAR (Adam & al. 2002) is also presented.

Water activity (Aw) measurement is a concept developed, and mainly used, by food-processing and pharmaceutical industries for Intermediate moisture products humidity control. Contrary to the water measurements such as moisture content (MC) that quantify the total amount of water in a product (quantitative analysis), Water activity illustrates the energy status of water and consequently its degree of availability and mobility in a product, it is a qualitative analysis. The Forest Ecosystems research team of Cemagref demonstrated that moisture management of pollen and seeds can be advantageously monitored via Aw measures. Water activity measurement is nondependent on the phenotypic variability of forest reproductive materials; this makes water activity a good predictor of pollen and seeds stability during storage. Since spring 2007, Cemagref cooperates with the Direction de la Recherche Forestière (DRF) and the Centre de Semences Forestières de Berthier (CSFB), both from Québec Ministry of Natural Resources, in order to establish Aw as a new criterion for seed and pollen management in the province. The three partners are convinced that many other tree seed centre concerned with orthodox seeds can implant successfully the Water activity technique. New collaborations on this topic could induce mutual benefits by improving general knowledge of forest reproductive material water dynamics prior and during storage., La mesure de l'activité de l'eau (AE) est un concept développé et principalement utilisé par les industries agro-alimentaires et pharmaceutiques pour le suivi de l'état hydrique des « produits à humidité intermédiaire ». Contrairement aux mesures comme la teneur en eau massique (TE) qui qualifient la teneur en eau totale d'un produit (mesures quantitatives), l'Activité de l'eau illustre le statut énergétique de l'eau et en conséquence son degré de disponibilité et de mobilité dans une matière, c'est une analyse qualitative. L'équipe de recherche Ecosystèmes forestiers du Cemagref a démontré que la gestion de l'état hydrique des graines et pollens pouvait être avantageusement traitée grâce à la mesure de l'activité de l'eau. La mesure de l'activité de l'eau est indépendante de la variabilité phénotypique des matériels forestiers de reproduction ; ceci donne à la mesure de l'AE un bon potentiel de prédiction de stabilité des graines et des pollens mis en conservation. Depuis le printemps 2007, le Cemagref coopère avec la Direction de la recherche Forestière et le Centre de Semences Forestières e Berthier appartenant au Ministère des Ressources Naturelles du Québec afin d'introduire l'AE comme un nouveau critère de gestion des semences et pollens dans la province. Les trois partenaires sont convaincus que d'autres centres de semences forestières concernés par les semences orthodoxes peuvent implanter avec succès la mesure de l'AE. De nouvelles collaborations sur ce thème pourraient induire des bénéfices mutuels par l'amélioration des connaissances relatives à la dynamique de l'eau dans les matériels forestiers de reproduction avant et pendant la mise en conservation.

L'objectif de cette communication est d'attirer l'attention des chercheurs souhaitant réaliser des synthèses bibliographiques d'avoir recours à la méta-analyse. Après avoir expliqué pourquoi les autres approches peuvent donner des résultats plus ou moins biaisés (revue narrative ou revue basée sur un décompte des études par catégorie selon la nature des résultats), le concept de méta-analyse est défini, puis la démarche à suivre pour la réaliser est explicitée. Elle est illustrée rapidement par un exemple en écologie forestière. L'état d'avancement d'une méta-analyse est présenté, qui porte sur les différences de biodiversité en des forêts gérées et non gérées et qui est réalisée dans le cadre du travail du groupe de travail RA3 d'Alter-net. La difficulté de mener à bien ce type d'approche sur des questions de biodiversité est soulignée. Il est indiqué enfin que cette approche quantitative est un des outils permettant de réaliser une revue systématique de manière rigoureuse.

Poster presenting BiodivSamp start-up project that aimed at optimising sampling strategies for biodiversity monitoring., Poster présentant l'initiative BiodivSamp, projet interne d'ALTER-Net qui visait à optimiser les stratégies d'échantillonnage pour le suivi de la biodiversité.

International audience; Anaplasma phagocytophilum is the agent of pasture fever or tick-borne fever, a disease of ruminants and humans in the United States and in Europe. Although several hundred cases have been suspected to occur in cattle in France, none has yet been microbiologically confirmed. We report the first identification of A. phagocytophilum 16S RNA gene sequence in a case of TBF in France. This indicates that the diagnosis of tick-borne fever should be also evoked in cattle exposed to Ixodes ticks in France.

As soon as 1988, the Council of Europe exhorted European governments to use prioritarily the saproxylic organisms in the evaluation of forest conservation status (Recommendations R(88)10 and 11). About twenty years later, only a few tools are available to satisfy this objective. Beetles stand for the second dominating group in saproxylic assemblages (20% of the total number of species). Databases focusing on this taxon were consequently developed, but only in several European countries (Scandinavia: Dahlberg et Stokland, 2004; Great-Britain: Alexander, 2002 ; Germany: Köhler, 2000, Schmidl et Bussler, 2004, Müller et al., 2005). In France, the rich saproxylic beetle fauna (ca 2300 species) is only partly covered by these databases. The first national project was a list of 300 species written by Brustel (2001) as a pragmatic conservation tool. This pioneer initiative now suffers from a poor representativeness (i) in a taxonomical point of view (only a 6th of the species and 40% of the families are represented), and (ii) in an ecological perspective (only mid-size, large and remarkable species were included). Our current project aims at building a national and homogeneous information system. Three steps are planned and still in progress : 1.to draw a complete taxonomical table of saproxylic beetle French fauna, based on a corrected update of the FaunaEuropaea ; 2.to compile the available autecological data in predefined variables for each species (larval trophic regime, larval micro-habitat, relation to flowers, tree species preference) ; functional analyses of the relationship between ecological groups and local dead wood profiles may thus be carried out ; 3.to attribute a patrimonial value to each species (in agreement with the approach of Alexander, 1988 and Brustel, 2001), in order to assess the conservation status of stands, forests, reserves, etc.

International audience; We investigated the relevance of understory vegetation in indicating site productivity as expressed by sessile oak (Quercus petraea Matt. Liebl.) site index over a large territory. The relationships between site index and (1) understory vegetation or (2) soil, topography and climate were studied using data from 99 even-aged high-forest stands located in northern France. Multiple regressions using floristic indices as predictors explained the same part of variance in site index as regressions using climate, topography, and soil factors (R2 = 0.49 to 0.60). However, better models were obtained by combining floristic and abiotic variables (R2 = 0.57 to 0.69). We concluded that (1) site productivity can be assessed with the same precision using understory vegetation or abiotic variables separately, even over a large region, but (2) it would be more appropriate to combine soil physical and chemical properties, climate and topography with floristic indices to estimate sessile oak site index.; L'objectif était d'étudier sur un vaste territoire la pertinence de la végétation du sous-bois pour prédire le niveau de productivité d'un peuplement, mesurée par l'indice de fertilité du chêne sessile (Quercus petraea Liebl.). Les relations entre cet indice et (1) la végétation du sous-bois ou (2) le climat, la topographie et le sol ont été étudiées sur 99 peuplements adultes de futaie régulière situés dans la moitié nord de la France. Les régressions multiples basées sur ces indices floristiques expliquent la même part de variance de l'indice de fertilité que les régressions basées sur le climat, la topographie et le sol (R²= 0,49 à 0,60). Cependant, de meilleurs modèles sont obtenus en combinant les variables floristiques et abiotiques (R²= 0,57 à 0,69). Nous concluons que la productivité d'une essence peut être évaluée avec le même niveau de précision en utilisant séparément la végétation du sous-bois et les descripteurs abiotiques, y compris sur un vaste territoire. Mais nous recommandons pour une meilleure estimation de combiner à la fois les propriétés physiques et chimiques du sol, le climat, la topographie et les indices floristiques.

Parents and progenies genetic diversity, and male and female contributions to the seed crop were assessed in three experimental Prunus avium seed orchards. Collected data were used to compare different effective population sizes, based on phenological, seed crop and paternity analysis. Our results did not show any difference of genetic diversity between parents and progenies. A limited pollen pollution was detected. We showed that distance and coflowering among clones had a significant effect on effective pollination, and a significant effect of the production of flowers was revealed in one of the seed orchards. Our study also revealed a quite low number of effective size of fathers per mother, but high effective sizes of mothers, fathers and parents at the level of the seed orchard. Finally, the calculation of effective size of mothers, fathers and parents was not highly modified when having the complete information based on the paternity analysis., La diversité génétique des parents et de leurs descendants, ainsi que les contributions mâle et femelle à la récolte de graines ont été estimées dans trois vergers à graines expérimentaux de Prunus avium. Les données collectées ont été utilisées pour comparer différentes tailles de population efficace, en se basant sur l'analyse de la phénologie, de la récolte de graines et de la paternité. Nos résultats n'ont pas montré de différence de diversité génétique entre les parents et les descendants. Une pollution pollinique limitée a été mise en évidence. Nous avons montré un effet significatif de la distance et de la cofloraison entre clones sur la pollinisation efficace, ainsi qu'un effet significatif de la production de fleurs dans l'un des vergers à graines. Notre étude a aussi révélé un faible nombre efficace de pères à l'échelle de chaque mère, et un nombre efficace de mères, de pères et de parents important à l'échelle du verger à graines. Enfin, le calcul des tailles efficaces de pères et de parents à l'échelle du verger à graines n'a pas été fortement influencé par le fait d'avoir l'information totale de contribution donnée par l'analyse de paternité.

Vascular plants and bryophytes of the 102 French ICP level II plots were recorded in 1995, 2000 and 2005. 15 teams of experienced botanists (one to three observers by team) participated in the surveys. The few studies that assessed the magnitude of observer effect in vegetation censuses found relatively high discrepancies between botanists; this questions the capacity of monitoring programs involving different botanists, to properly track changes in plant communities, especially in mature forest stands where plant communities could be expected to change slowly. Therefore, a quality control-quality assurance (QA-QC) procedure was repeated every five years (1) to assess the magnitude of the observer effect, (2) to reduce it as much as possible, and (3) to be able to take the observer effect into account in the analyses of the temporal change of plant communities. The procedure was based upon random control visits (each team visited one plot sampled by another team shortly after) and a two-day inter-calibration training (Camaret et al. 2004). During this training, all the teams first carried out censuses independently on the same set of plots and then returned all together on these plots to reach a consensus on the list of species and their cover (so as to evaluate the mean census exhaustiveness and the level of overlooking and identification errors). Different objectives were assigned to control visits and to inter-calibration training. Control visits helped estimating the pseudo-turnover (PT), i.e. the actual noise in the vegetation data, whereas inter-calibration training primarily aimed at calibrating teams and thus reducing data noise as much as possible. We analysed between-observer differences in the estimation of plant cover and in the number of species detected and compared the apparent turnover (using diachronic surveys) to the pseudo-turnover (using control visits). Cover estimation. The lowest and highest Braun-Blanquet classes reported by the different teams differed by two or more classes in more than 30% the observed species. The discrepancies between observers varied in a parabolic way with the plant cover and were highest for species with Braun-Blanquet class 3 or 4, which are most often found in the tree layer. Some teams tended to note the consensual cover more often than others; some other teams had a propensity to bias low or high plant cover. The proportion of cases where cover estimates differed by at least two Braun-Blanquet classes between teams decreased with the repetition of the inter-calibration exercises along the years. Species richness. Systematic differences in mean species richness were found between teams in all years. About 20% of the plant species were missed on average. The relative exhaustiveness of the censuses increased with the number of plants in the plot, the number of people in the team, the number of other vegetation censuses carried out during the last three months before inter-calibration, and with the time spent recording species in the plot. The level of exhaustiveness tended to be lower in the understory (especially the bryophyte layer) than in the tree layer, certainly because most low cover plants are found in the understory. Turnover and pseudo-turnover. We calculated the mean (apparent) turnover from 1995/2000/2005 censuses and the pseudo-turnover from control visits in order to compare their respective magnitudes. The mean turnover was 26.1 ± 0.3% (standard error), but was 25.0 ± 0.3% if the same team had made the two consecutive surveys and 28.9 ± 0.7% if two different teams successively carried out the censuses. The mean pseudo-turnover was equivalent to the apparent turnover (mean value = 26.2 ± 0.7%; no year effect, no influence of the number of days between the two visits on the same plot, except in 2005). This PT value is close to other published values (Nilsson and Nilsson 1985, Scott and Hallam 2002). Recommendations. The main recommendation is that plant surveys should be conducted by experienced botanists being familiar with the local flora. Data quality could be further improved using teams of observers, as recommended by Klime et al. (2001), even if not all are experts. Training by carrying censuses before the start of the survey will be beneficial. Inter-calibration reduces between-observer differences in cover estimation and can probably convince botanists of the necessity to carefully check all specimens of species prone to misidentification, especially in rich areas or in dense ground vegetation. Because species are much more often missed than misidentified, enhancing fieldworker's motivation and, thus, attention (e.g. by regular contacts, inter-calibration exercises) must be, obviously, a key component of any plant survey, probably more important than training. During the survey and especially if it is part of a repeated monitoring program, botanists should always note their doubts about species identifications as this may help linking observations over time. Furthermore, suspicious records could be deleted in subsequent analyses if necessary. Although our results may give a pessimistic view of the quality of vegetation data, it must be noted that the high observer effects we obtained only concern species composition and cover. On the opposite, many global indices of plant communities, such as Ellenberg indicator values, are very repeatable (Lep and Hadincová 1992, Gray and Azuma 2005, Archaux et al. 2006)., Les plantes vasculaires et les bryophytes des 102 placettes françaises du réseau PIC (niveau 2) ont été échantillonnées en 1995, 2000 et 2005. 15 équipes de botanistes expérimentés (1 à 3 observateurs par équipe) ont participé à ces campagnes d'échantillonnage. Les quelques études qui ont estimé la magnitude de l'effet observateur dans les relevés floristiques ont mis en évidence des différences relativement importantes entre botanistes ; cette observation met en doute la capacité des programmes de suivi faisant appel à différentes équipes de botanistes à estimer correctement l'évolution de la flore, en particulier dans des peuplements matures où les communautés végétales évoluent lentement. C'est pourquoi une procédure de contrôle qualité-assurance qualité a été répétée tous les 5 ans (1) pour estimer la magnitude de l'effet observateur, (2) de réduire cet effet au maximum, et (3) de pouvoir prendre en compte cette effet dans les analyses des changements temporels des communautés végétales. La procédure est basée sur des visites aléatoires de contrôle (chaque équipe échantillonne une visite préalablement échantillonnée par une autre équipe quelques semaines auparavant) et un exercice d'intercalibration de deux jours (Camaret et al. 2004). Durant cet exercice, toutes les équipes réalisent les relevés floristiques indépendamment les unes des autres et retournent ensuite ensemble pour établir la liste des espèces présentes de façon consensuelle (et leur recouvrement) (de façon à évaluer l'exhaustivité moyenne des relevés, le taux d'espèces non détectées et mal identifiées). Plusieurs objectifs ont été assignés aux visites de contrôles et aux exercices d'intercalibration. Les visites de contrôles permettent d'estimer le pseudo-turnover (PT), c'est-à-dire le bruit dans les données de végétation du réseau, tandis que les exercices d'intercalibration ont pour but principal de calibrer les équipes et donc de réduire les différences entre équipes au maximum avant les campagnes de relevés. Nous avons analysé les différences entre équipes sur le recouvrement des espèces et la richesse spécifique et comparé le turnover apparent (à partir des données diachroniques du réseau) au pseudo-turnover (à partir des visites de contrôle). Estimation du recouvrement. Pour plus de 30% des espèces observées, les valeurs de recouvrement ( selon l'échelle semi-quantitative de Braun-Blanquet) données par les différentes équipes différaient de 2 classes ou plus. Les désaccords entre équipes augmentent avec le recouvrement (consensuel) de façon parabolique et sont maximaux pour les classes de Braun-Blanquet 3 ou 4, qui sont le plus souvent rencontrés dans la strate arborée. Certaines équipes ont une meilleur capacité à indiquer le recouvrement consensuel que d'autres, tandis que certaines équipes biaisaient positivement ou négativement le recouvrement des plantes. La proportion de cas où les estimations de recouvrement différaient d'au moins 2 classes de Braun-Blanquet classes entre équipes a diminué avec la répétition des exercices d'inter-calibration. Richesse spécifique. Des différences systématiques de richesse spécifique moyenne ont été décelées entre équipes pour toutes les années. En moyenne, 20% des espèces ont été ratées. L'exhaustivité relative des relevés a crû avec le nombre d'espèces dans la placette, le nombre de botanistes de l'équipe, le nombre de relevés effectués Durant les trois mois précédents l'exercice d'inter-calibration et avec le temps passé à rechercher les espèces dans la placette. Le niveau d'exhaustivité tendait à être plus bas pour les strates basses (en particulier la strate muscinale), certainement parce que la plupart des espèces peu abondantes (recouvrantes) s'y trouvent. Turnover et pseudo-turnover. Nous avons calculé le turnover (T) moyen (apparent) à partir des relevés 1995/2000/2005 et le pseudo-turnover (PT) à partir des relevés de contrôle de façon à comparer leur magnitude. Le T moyen était 26.1 ± 0.3% (erreur standard), mais 25.0 ± 0.3% si la même équipe a réalisé les relevés des deux campagnes successives et 28.9 ± 0.7% si deux équipes différentes ont réalisé successivement les relevés. Le PT moyen est équivalent au T apparent (valeur moyenne = 26.2 ± 0.7%; pas d'effet de l'année, pas d'influence du nombre de jours entre les deux visites sur les mêmes placettes, hormis en 2005). Cette valeur de PT value est proche de celles déjà publiées (Nilsson et Nilsson 1985, Scott et Hallam 2002). Recommandations. La recommandation principale est que les relevés floristiques devraient être conduits par des équipes expérimentées, familiers avec la flore locale. La réalisation des relevés en équipes permettrait d'améliorer également la qualité des données, comme le recommande Klime et al. (2001), même dans les cas où tous ne sont pas experts. L'entraînement avant les campagnes d'échantillonnage serait également bénéfique. L'inter-calibration diminue les désaccords entre équipes sur le recouvrement des espèces et permet probablement de convaincre les équipes de la nécessité de vérifier attentivement tous les spécimens des espèces délicates à identifier, en particulier dans les zones riches ou avec une végétation dense. Parce que les espèces sont bien plus fréquemment ratées que mal identifiées, un élément crucial de toute campagne floristique est de s'assurer de la motivation constante des observateurs et donc de leur attention (par exemple en les contactant régulièrement et en réalisant des exercices d'inter-calibration), probablement plus que l'entraînement. Durant la campagne et surtout si cette campagne s'inscrit dans un programme de suivi, les observateurs devraient noter leurs doutes sur l'identification des espèces de façon à pouvoir relier des observations discordantes entre deux campagnes. En outre, ces données suspectes peuvent être éliminées des analyses si nécessaire. Bien que ces résultats peuvent donner une vision pessimiste de la qualité des relevés de végétation, il faut mentionner que ces résultats ne concernent que la composition et le recouvrement des espèces. A l'opposé, de nombreux indices globaux des communautés végétales, comme les valeurs indicatrices d'Ellenberg, sont très répétables (Lep et Hadincová 1992, Gray et Azuma 2005, Archaux et al. 2006).

International audience; Evenness is the component of species diversity that was built to be mathematically independent from species richness. Yet, earlier work questioned the generality of this independence. However, this earlier work involved only a few relative abundance distributions (RADs), very limited gradients of species richness, or evenness indices, such as Pielou's index, that were not defined in relation to a precise, coherent set of axioms. We show that for very different theoretical RADs, a relationship between evenness indices and species richness does exist and is strongat least for some RADs and/or when species richness is under 20. Furthermore, this relationship is mostly negative, which contradicts some previous studies. We also show that, for the very uneven RADs we tested, evenness indices depend even more on species richness than diversity indices do. Finally, we discuss the philosophy behind the analysis of evenness-richness relationships within and between RADs, as well as the interest of correcting evenness indices for species richness when species richness varies, especially with many values under 20.; L'équitabilité est la composante de la diversité spécifique construite de façon à être mathématiquement indépendante de la richesse spécifique. Pourtant, des travaux antérieurs ont remis en cause la généralité de cette indépendance. Ces travaux étaient néanmoins limités par le faible nombre de distributions d'abondance relatives (DAR) étudiées, des gradients de richesse spécifique réduits ou des indices d'équitabilité, tels que l'indice de Piélou, qui n'ont pas été défini dans un cadre axiomatique clair. Nous montrons ici que pour des DAR théoriques très différentes, une relation entre équitabilité et richesse spécifique existe et est forte - au moins pour certaines DARs ou quand la richesse spécifique est en-dessous de 20. De plus, cette relation est généralement négative, à l'inverse de résultats antérieurs. Pour certaines DARs très inéquitables, les indices d'équitabilité dépendent même plus de la richesse spécifique que ne le font les indices de diversité. Nous discutons enfin ces résultats ainsi que l'intérêt d'éventuellement corriger les indices d'équitabilité par rapport à la richesse spécifique, notamment quand la richesse spécifique est souvent sous le seuil de 20.

Ce rapport présente les avancées réalisées sur les méta-analyses du groupe de travail RA3 du réseau Alter-net. L'intérêt des méta-analyses est présenté avec les procédures et les tests statistiques associées, puis le cas choisi de la méta-analyse dans le cadre du WP RA3 est détaillé : sont présentés le protocole suivi, les premiers résultats de la recherche effectué et de la sélection des papiers par les 16 participants du groupe, le plan de travail pour la suite et enfin le plan de l'article prévu pour valoriser le travail.

As soon as 1988, the Council of Europe exhorted European governments to use prioritarily the saproxylic organisms in the evaluation of forest conservation status (Recommendations R(88)10 and 11). About twenty years later, only a few tools are available to satisfy this objective. Beetles stand for the second dominating group in saproxylic assemblages (20% of the total number of species). Databases focusing on this taxon were consequently developed, but only in several European countries (Scandinavia: Dahlberg et Stokland, 2004; Great-Britain: Alexander, 2002 ; Germany: Köhler, 2000, Schmidl et Bussler, 2004, Müller et al., 2005). In France, the rich saproxylic beetle fauna (ca 2300 species) is only partly covered by these databases. The first national project was a list of 300 species written by Brustel (2001) as a pragmatic conservation tool. This pioneer initiative now suffers from a poor representativeness (i) in a taxonomical point of view (only a 6th of the species and 40% of the families are represented), and (ii) in an ecological perspective (only mid-size, large and remarkable species were included). Our current project aims at building a national and homogeneous information system. Three steps are planned and still in progress : 1.to draw a complete taxonomical table of saproxylic beetle French fauna, based on a corrected update of the FaunaEuropaea ; 2.to compile the available autecological data in predefined variables for each species (larval trophic regime, larval micro-habitat, relation to flowers, tree species preference) ; functional analyses of the relationship between ecological groups and local dead wood profiles may thus be carried out ; 3.to attribute a patrimonial value to each species (in agreement with the approach of Alexander, 1988 and Brustel, 2001), in order to assess the conservation status of stands, forests, reserves, etc.

Different methods, such as extraction cylinders, coloured traps, are used to sample saproxylic beetles. Window-flight trapping is the most frequently used technique for catching flying active saproxylic beetles. Window-flight trap devices may differ by the following parameters: plate area, plate shape (plane or crossed), plate colour (transparent or black), bait. Several compiled ecological data sets were analysed with a methodological point of view to compare sampling methods. In the goal of harmonizing sampling methods among studies, this approach aimed at identifying if some sampling methods perform better than others in terms of accuracy, precision and bias to evaluate the cumulative species richness, the species abundance or the assemblage composition. Different analytical methods (power analysis, detectability and exhaustiveness, resampling) were used to compare : -alcoholic-baited or unbaited traps -black- or transparent-window traps -crossed or plane-window traps. Moreover, although biased data are sufficient to address the question of relative differences, it must be assumed that biases are the same between the locations that are being compared. Detectability must not change with habitat structure. That's why we studied the variations in catch efficiency of alcohol-baited or unbaited traps in sun-exposed or shaded conditions. In other words, does trap attractiveness depend on the openness ? The question of the seasonal pattern of sampling across the year was also tackled. First, we assessed the contribution of each sampling season to richness and composition. Secondly we studied the effects of the simplification of a year-catch strategy into a discontinuous trapping design on the representativeness of samples. The available datasets mainly concerned issues at the plot scale and came from forest balanced sampling designs with paired traps on each plot. This saproxylic workshop will give us the opportunity to launch a call for further optimisation analyses based on larger datasets.

To model the growth of heterogeneous (uneven-aged or mixed) stands, the use of individual based models seems more appropriate, because of the individual variability within heterogeneous stands. However, forest managers cannot easily use this kind of models, especially because they require knowing the localisation of each tree in order to run simulations. However, it is possible to use our knowledge on stand level characteristics for a forest stand as rules to build a virtual stand, which will be close to the real stand, and which could be used as initial state for an individual based model. This approach corresponds to the development of a model of spatial structure. Our aim is to explain the principle of the development of such a model, and to illustrate it on the case of oak- Scots pine mixed stands. First step consists on characterizing the spatial structure of the studied stand. In our example, we built a typology of spatial structure of these stands; we will present the main spatial types identified. Second step specifies how to use adapted statistical tools - point processes - to build a model of spatial structure from the identified types. Finally, we will show how such a model of structure would help simulating realistic initial states, which would facilitate the use of individual based growth model.

1. The literature on bark-stripping by red deer in Europe is reviewed to reveal quantitative variation in this behaviour and relate it to deer density and local characteristics such as dominant tree species, occurrence of artificial feeding, altitude, region and size of the study site. We also review the importance of bark in red deer diets over the seasons and discuss the causes of bark-stripping particularly the hypothesis of bark as food. 2. Over the 36 sites examined, the rate of bark-stripping was highly variable (from 0 to 84% of susceptible trees debarked), with less damage in Scotland than in other European sites for which bark-stripping rate was higher at high red deer density. The altitude, the size of the study site, the number of dominant tree species and the occurrence of artificial feeding do not significantly relate with the rate of bark-stripping. 3. Bark sometimes made up a large proportion of red deer diet (>10%), especially in areas with severe winters (high levels of snow), whereas in study sites with mild winters bark was practically not eaten at all. 4. These results suggest that severe bark-stripping could be related to a decrease of food resources availability. This food resource hypothesis need to be better documented and particularly the possible interaction between food availability and red deer density., 1 La littérature disponible sur l'écorçage causé par le Cerf élaphe en Europe est passé en revue pour évaluer la variation de ce comportement et la mettre en rapport avec la densité des populations, la présence d'affouragement, l'altitude, et la taille des sites d'études. Nous avons passé en revue les informations sur l'importance des écorces dans le régime alimentaire des cerfs en fonction des saisons et discuté des causes de l'écorçage en se concentrant sur le rôle des écorces comme source de nourriture. 2 Sur les 36 sites examinés, le taux d'écorçage varie de 0 à 84% du nombre de tiges sensibles, avec des dégâts moindres en Ecosse par rapport à d'autres pays européens. L'altitude, la taille du site, le nombre d'essences forestières dominantes et la pratique de l'affouragement ne sont pas corrélés à l'importance des dégâts. 3 L'écorce peut représenter une grande proportion du régime alimentaire du cerf (> 10%) spécialement dans des secteurs géographiques où les hivers sont rigoureux (à fort enneigement), tandis que dans les sites à hivers doux, l'écorce n'est pratiquement pas consommée. 4 Ces résultats suggèrent que des dégâts d'écorçage importants pourraient être dus à des disponibilités alimentaires insuffisantes. Cette hypothèse mérite d'être validée en tenant compte des interactions possibles entre disponibilité en ressources et densité de cerf.

The monitoring of biodiversity in space and time is the only way to show the impact of some pressures (e.g. in long-term ecosystem research sites LTER) and to assess the efficiency of conservation and restoration measures (e.g. in reserves, Natura 2000). Sampling methods must therefore be adapted to the studied taxa, be efficient towards the objective of the monitoring and be standardised to enable comparisons in space and time within the study and, hopefully, among studies. Moreover, sampling methods have to result from a compromise between level of exhaustiveness, comparability and feasibility. This goal of standardising, simplifying and harmonizing sampling methods is particularly relevant in the context of large scale monitoring in LTER sites, at the European level. Several national or European initiatives were devoted to these questions but they were restricted to a few biogeographical regions or taxonomic groups. Sampling methodologies need therefore to be assessed and optimised using some common methodology. Their efficiency and repeatability should be checked in a wider context -from the local and site scale to the global scale as ecological processes are likely to be expressed on different spatial and temporal scales. The purpose of this work would be to improve or even develop new sampling designs and to propose some integrated biodiversity monitoring for LTER sites. More precisely, the project will raise questions about (a) factors affecting elementary samples (bias, accuracy), (b) aggregation of samples in space and time and its links with the underlying mechanisms, (c) alternative allocation of effort between various spatial and temporal scales, always bearing the cost-effectiveness of the proposed methods in mind.

International audience; The short-term effect of windthrow gap size and isolation for saproxylic beetle abundance, species richness and assemblage composition was studied in managed oak-hornbeam forest in France. The main gap effects did not increase with gap area. Nonmetric multi-dimensional scaling (NMDS) and ANOSIM tests showed that all gaps, even small, differed from closed-canopy controls in terms of saproxylic species composition. However, only mid-size gaps were distinct from large and especially small gaps. The highest Bray-Curtis dissimilarity occurred between mid-size gaps and closed-canopy controls, and not between large gaps and controls. Partly in agreement with the resource concentration hypothesis, floricolous beetles were more abundant in mid-size and large gaps than in small ones. However, pioneer xylophagous species did not increase and late-successional xylophagous species did not decrease in abundance with increasing gap area. A peak in cumulative and mean local species richness was measured in midsize gaps, but assemblage composition in mid-size gaps was not intermediate between small and large gaps, which does not fully comply with the intermediate disturbance hypothesis. From IndVal results, no strictly characteristic species were detected in small gaps, but several ones in mid-sized and large gaps. On the whole, scolytids and pioneer xylophagous beetles were favoured in gaps by an increase in felling density in the 78 and 314 ha surrounding landscapes, respectively. Individual species responses in occurrence or abundance were varied. As the faunistic peculiarity in the gaps was mainly confined to mid- and large-sized gaps, retaining uncleared gaps above 0.5 ha in size is recommended to improve saproxylic gamma diversity in forests.

The monitoring of biodiversity in space and time is the only way to show the impact of some pressures (e.g. in long-term ecosystem research sites LTER) and to assess the efficiency of conservation and restoration measures (e.g. in reserves, Natura 2000). Sampling methods must therefore be adapted to the studied taxa, be efficient towards the objective of the monitoring and be standardised to enable comparisons in space and time within the study and, hopefully, among studies. Moreover, sampling methods have to result from a compromise between level of exhaustiveness, comparability and feasibility. This goal of standardising, simplifying and harmonizing sampling methods is particularly relevant in the context of large scale monitoring in LTER sites, at the European level. Several national or European initiatives were devoted to these questions but they were restricted to a few biogeographical regions or taxonomic groups. Sampling methodologies need therefore to be assessed and optimised using some common methodology. Their efficiency and repeatability should be checked in a wider context -from the local and site scale to the global scale as ecological processes are likely to be expressed on different spatial and temporal scales. The purpose of this work would be to improve or even develop new sampling designs and to propose some integrated biodiversity monitoring for LTER sites. More precisely, the project will raise questions about (a) factors affecting elementary samples (bias, accuracy), (b) aggregation of samples in space and time and its links with the underlying mechanisms, (c) alternative allocation of effort between various spatial and temporal scales, always bearing the cost-effectiveness of the proposed methods in mind.

The aim of this poster communication presented at the fifth workshop IUFRO 5.01.04 WP is to show how spatial structure analysis can be used to improve our knowledge of heterogeneous forest and to provide some perspectives for their modelling. In order to answer this question, we applied an analysis of spatial structure to a mixed stand of Oak and Scots pine from French Centre area. We used the classical Ripley function L(r), and intertype function L12(r) to characterise the specific spatial structure of each population, and the structure of the interaction between populations. We then used the results of this analysis to build a typology of these stands. We identified four main types, and used the general observed spatial structures to make assumptions about ecological processes and historical factors influencing the dynamics of these stands. In a second step, we used the typology in order to build a model of the spatial structure, that can simulate realistic virtuals stands from data at the stand scale classically used by forests managers. We finally discuss the advantages of using such realistic virtual stands as initial states for distance dependant individual based models, when simulating the growth and the dynamic of mixed stands., Ce poster présenté au 5ème colloque IUFRO 5.01.04 WP a pour but de montrer comment la structure spatiale permet d'améliorer notre connaissances des peuplements hétérogènes et de fournir des pistes à leur modélisation. Pour cela, nous avons étudié les peuplements mélangés chêne-pin sylvestre de la région Centre. Nous avons analyser leur structure spatiale en utilisant les fonctions L(r) de Ripley et la structure du mélange par la fonction L12 de Lotwick et Silvermann. Les résultats de cette analyse nous ont permis de construire une typologie de ces peuplements. Les diverses structures spatiales observées nous ont permis de faire des hypothèses sur les processus écologiques et historiques influençant la dynamique des ces peuplements. Nous utilisons dans un deuxième temps cette typologie pour construire un modèle de structure et simuler des peuplements virtuels réalistes, pouvant servir d'état initial pour des modèles individus-centrés dépendant des distances.

On its first Call for proposals, ALTER-Net Network of excellence funded the development phase of a project ("BiodivSamp") about the optimisation of sampling strategies for biodiversity monitoring, that was coordinated by the Cemagref. Such a phase is devoted to create a working group and identify common research questions on the selected research topic. Using the material gathered through an electronic conference that was organised by the Cemagref on the ALTER-Net Internet WebBoard (October 2005), this document assesses the fields, skills and common research interest within the BiodivSamp group, with a view to building up a methodological research project within ALTER-Net. It contains the list of the studied taxa, the used sampling methods and the investigated biogeographical regions within the working group. Two main research topics were identified : (1) simplifying sampling designs in existing monitoring networks, (2) assessing biases caused by sampling method attributes (observer, time-period, environmental conditions, etc). Examples of research questions are formulated for the whole or particular taxa. Needs in data sets and statistical methods are identified., A l'occasion du premier appel à propositions de recherche, le réseau ALTER-Net a décidé de financer, au titre du développement du projet, un projet présenté par le Cemagref sur l'optimisation des stratégies d'échantillonnage pour les suivis de biodiversité ("BiodivSamp"). Cette phase de développement consiste en l'activation d'un groupe de travail et la formalisation de questions de recherche communes. A partir d'une conférence électronique organisée par le Cemagref sur la plate-forme internet d'ALTER-Net, ce document fait le bilan des compétences et des champs d'action des partenaires du projet, en vue de construire un projet de recherche méthodologique au sein d'ALTER-Net. Les taxons étudiés, les méthodes d'échantillonnages utilisées et les régions biogéographiques investiguées au sein du groupe de travail sont listés. Les deux principaux enjeux de recherche émergeant lors de la conférence électronique concernent (i) la simplification de plan d'échantillonnage pour des suivis existants, (ii) l'évaluation des biais liés aux attributs des méthodes d'échantillonnage (observateur, période, conditions environnementales, etc). Des exemples de questions de recherche sont proposés pour tous ou certains groupes taxonomiques. Pour chacune des ces questions de recherche, les besoins en termes de jeux de données et méthodes statistiques sont identifiés.

The case of the Northern spotted owl (Strix occidentalis caurina) has now become now a classical case-study in conservation biology. It has been characterized by a harsh struggle between environmental and pro-indutrial lobbies, including during law suits, that was finally partly solved by the Northwest Forest Plan in 1993. However, this case study was also interesting because of the ecological research performed, and the links between research and management it involved. This is the point we would like to discuss here: how did research results feed management debates and choices? How was the link between both organized? Did the different time frames and cultures manage to work together? In so doing, we will mainly have a monodisciplinary, ecological perspective., La chouette tachetée nordique représente désormais un cas classique en biologie de la conservation, marqué par des conflits et des procès opposant écologistes et industriels ainsi que des fonds conséquents investis dans la recherche et un plan de gestion des forêts fédérales du Nord-Ouest des Etats-Unis. Mais l'un des principaux intérêts de ce cas est de nous amener à réfléchir sur les liens entre recherche et gestion en biologie de la conservation. Comment les résultats de la recherche ont-ils alimenté le domaine de la gestion, ses débats et ses choix ? Comment ces liens ont-ils été organisés ? Les pas de temps et cultures différents ont-ils réussi à travailler ensemble ? Comment organiser ce lien dans les contexte d'une gestion ou d'une politique réfractaire à la prise de risques ?

Resistance breeding of the native elms against Dutch elm disease, caused by the fungus Ophiostoma novo-ulmi Brasier, is a major objective in Europe for the conservation of this tree species. More than 2,500 cuttings of 324 elm clones (Ulmus minor Miller, U. glabra Huds., U. laevis Pall., U. pumila L., U. minor x U. glabra, and U. minor x U. pumila) from eight European countries, planted in several randomized two-block designed plots were inoculated with various O. novo-ulmi strains. Crown wilting and dieback were recorded during the first year after inoculation. The wilting of the control trees varied among the plots, making the results difficult to compare, but analysis of variance (ANOVA) within each plot showed significant differences in disease severity among the clones tested, allowing study of the variation of the response among elm taxa. Results showed that 19 European inoculated clones recovered from O. novo-ulmi attack, giving hope for the reestablishment of native elms in countryside hedges and forests.

On its first Call for proposals, ALTER-Net Network of excellence funded the development phase of a project ("BiodivSamp") about the optimisation of sampling strategies for biodiversity monitoring, that was coordinated by the Cemagref. Such a phase is devoted to create a working group and identify common research questions on the selected research topic. Using the material gathered through an electronic conference that was organised by the Cemagref on the ALTER-Net Internet WebBoard (October 2005), this document assesses the fields, skills and common research interest within the BiodivSamp group, with a view to building up a methodological research project within ALTER-Net. It contains the list of the studied taxa, the used sampling methods and the investigated biogeographical regions within the working group. Two main research topics were identified : (1) simplifying sampling designs in existing monitoring networks, (2) assessing biases caused by sampling method attributes (observer, time-period, environmental conditions, etc). Examples of research questions are formulated for the whole or particular taxa. Needs in data sets and statistical methods are identified., A l'occasion du premier appel à propositions de recherche, le réseau ALTER-Net a décidé de financer, au titre du développement du projet, un projet présenté par le Cemagref sur l'optimisation des stratégies d'échantillonnage pour les suivis de biodiversité ("BiodivSamp"). Cette phase de développement consiste en l'activation d'un groupe de travail et la formalisation de questions de recherche communes. A partir d'une conférence électronique organisée par le Cemagref sur la plate-forme internet d'ALTER-Net, ce document fait le bilan des compétences et des champs d'action des partenaires du projet, en vue de construire un projet de recherche méthodologique au sein d'ALTER-Net. Les taxons étudiés, les méthodes d'échantillonnages utilisées et les régions biogéographiques investiguées au sein du groupe de travail sont listés. Les deux principaux enjeux de recherche émergeant lors de la conférence électronique concernent (i) la simplification de plan d'échantillonnage pour des suivis existants, (ii) l'évaluation des biais liés aux attributs des méthodes d'échantillonnage (observateur, période, conditions environnementales, etc). Des exemples de questions de recherche sont proposés pour tous ou certains groupes taxonomiques. Pour chacune des ces questions de recherche, les besoins en termes de jeux de données et méthodes statistiques sont identifiés.

International audience; In most temperate deciduous forests, windstorm is the main source of dead wood. However, the effects of this natural disturbance on ambrosia and bark beetle communities are poorly known. In managed oak-hornbeam forests storm-damaged in France in 1999, we sampled ambrosia (and secondly bark beetles) by ethanol-baited window-flight traps in 2001. By comparing uncleared gaps, undisturbed closed-canopy controls and seedling-sapling stands, we investigated the short-term effects of gap formation, gap size and surrounding landscape to provide a snapshot of scolytid response. Contrary to expectations, neither the abundance nor the richness of ambrosia beetle species was significantly higher in gaps than in undisturbed stands. Few responses in abundance at the species level and only a slight difference in assemblage composition were detected between gaps and closed-canopy controls. Gaps were more dissimilar from seedling-sapling stands, than from closed-canopy controls. More scolytid individuals and species were caught in gaps than in seedling-sapling stands. Mean local and cumulative richness peaked in mid-size gaps. Only mid-size gaps differed from closed-canopy controls in terms of species composition. We identified generalist gap species (Xyleborus saxesenii, X. cryptographus), but also species significantly more abundant in mid-size gaps (Platypus cylindrus, Xyloterus signatus). The faunistic peculiarity of mid-size gaps seemed to be partly related to a bias in oak density among gap size classes. Few landscape effects were observed. Only the scolytids on the whole and X. dispar were slightly favoured by an increasing density in fellings at the 78ha scale. We did not find any correlation between scolytid abundance and the surrounding closed-forest percentage area. We confirmed that temperate, deciduous, managed stands did not come under threat by ambrosia and bark beetle pests after the 1999 windstorm. Nonetheless, our data stressed the current expansion in western Europe of two invasive species, Xyleborus peregrinus and especially X. germanus, now the predominant scolytid in the three oak forests studied.

International audience; Windstorm is the main natural disturbance in temperate forests. Canopy perforation induces important ecological changes in terms of microclimate and ground microhabitats and creates patchy open areas in the forest mosaic. In managed oak-hornbeam forests storm-damaged in France in 1999, we sampled carabid beetles by pitfall and window-flight interception traps in 2001. I compared ground beetle assemblages in unlogged natural openings vs closed forests. I studied short-term gap and gap size effects on carabid abundance, richness and assemblage composition (species and ecological groups based on habitat preference). Shortly after the disturbance, I observed a diversification of ground beetle assemblages in gaps at both air and ground levels in spite of a lower abundance in pitfall traps. The cumulative species richness for an equal sampling effort was greater in gaps (even in small ones) than in the closed forest. This richness increased with increasing gap area. Some forest species significantly declined in gaps, but none disappeared. Other forest species remained unaffected and several corticolous and arboricolous species were even favoured. Gap area did not significantly affect the forest group. Several open-land species appeared or increased in abundance in gaps. Their colonization was favoured by gap area. The assemblage composition, studied by NMDS and ANOSIM test, clearly differed between gaps (even small) and forest controls. Gaps larger than 0.3 ha were grouped according to the composition and colonization of open-land species. In uncleared gaps, the short-term community dynamics was dominated by colonization rather than local extinction processes.

Biodiversity is a complex matter related to a developing scientific field. In these conditions, we think both simple and more complex, research related indicators should be tested. We propose that both sets of indicators be dynamically related, and especially insist here on the way complicated indicators, found to be more accurate than currently preferred simple indicators, could be incorporated to a list of simple indicators. We apply the method to a case study. We find that models of species abundance of the herbaceous layer vegetation based on ecological gradients of tree species richness and tree species evenness behave poorer than models based on gradients of tree abundance. We propose two ways to implement these more complicated models into new lists of simple indicators., Dans le cadre de la stratégie pour diminuer l'érosion de biodiversité d'ici 2010, des approches sectorielles sont mises en oeuvre. L'un des outils de ces approches sont des indicateurs de biodiversité, assez souvent basés sur des concepts scientifiques ou des idées généraux. Nous proposons de soumettre ces indicateurs de biodiversité sectoriels à des tests de qualité sur des données réelles. Nous présentons un tel test sur des indicateurs de richesse et de mélange d'essences en milieu forestier pour la biodiversité floristique. Nous trouvons que ces indicateurs expliquent moins bien la biodiversité floristique que des indicateurs d'abondance des essences. Nous discutons comment de telles approches peuvent être intégrées dans les dispositifs d'indicateurs sectoriels.

The geographic and demographic expansion of large herbivores in Europe leads to situations where many species live in sympatry: this is the case for red and roe deer in France. To monitor a given species, indirect methods based on signs like faeces, tracks or beds have been used for a long time. They are generally cheap and accurate. However, signs look similar between red and roe deer even though the former is larger than the latter. Our goal was to test if different bed characteristics (size, scraping) and adjacent signs (tracks, faeces, rubbing...) are sufficient to reliably distinguish between red and roe deer presence in the field. This practical question is part of a larger project on bed site selection by sympatric red and roe deer.

International audience; Windstorm created small gaps with large amounts of sun-exposed dead wood in managed oak-hornbeam forest in France in 1999. The short-term effect of these gaps for saproxylic beetle abundance, species richness and assemblage composition were compared with closed-forest stands and seedling-sapling stands. We observed a strong differentiation of saproxylic assemblage in gaps compared with undisturbed stands but richness was only slightly higher in gaps. Contrary to expectations, the abundance of primary wood consumers on the whole, highly dominated by bark beetles, was as high in undisturbed plots as in gaps. However, longhorn and buprestid beetles responded positively in gaps. The later-successional xylophagous beetles on the whole were not significantly less abundant in gaps, in spite of the lower abundance of some shade-preferring species (Anobiidae, Eucnemidae, Melandryidae). Gap changes had a positive impact on the floricolous and xylomycetophagous insects, even if the species response was contrasted. Saproxylic communities were also distinct in gaps and in seedling-sapling stands. Both species richness and number of characteristic species were higher in gaps than in seedling-sapling stands. The abundance of later-successional xylophagous and xylomycetophagous insects was equal in gaps and in seedling-sapling stands. The abundance of saproxylic predators seemed to follow the population levels of all xylophagous insects. Because of their richness and faunistic dissimilarity with other open stands and closed-canopy controls, uncleared gaps may enhance the gamma diversity at the forest scale. In response to management issues underlying this research project, saproxylic diversity would benefit from the maintenance of some uncleared gaps. Moreover, in managed temperate, deciduous forests, my results suggest to retain more sun-exposed harvesting residue in fellings in order to enhance biodiversity.

Are ecological traits good surrogates for carabid species response to anthropogenic pressures? We assessed and compared parametric multi-species models of carabid response to regeneration felling at two levels: species level and ecological group level based on species habitat preference, flight ability and the combination of both. Within the 20 years following regeneration felling of old oak coppice with standards (Montargis forest, France), species responses were contrasted: their abundance either increased, decreased or remained steady. The carabid responses were best explained by habitat preference, then by the combination of habitat preference and flight ability and they were worst explained by flight ability alone. However, some ecological groups did not respond as expected from the literature. In any case, the studied ecological traits did not summarise all the species information, in terms of AICc, probably because of opposite responses within a same ecological group or because more traits are required to define species ecology.

International audience; Surveys conducted SINCE 1998, showed that symptoms typical of Elm yellows (EY) were quite frequent in the elm conservatories of Nogent-sur-Vernisson and Guéméné-Penfao, France and on forest trees in several locations in western Europe. Phytoplasmas were detected in symptomatic trees and plants using Polymerase Chain Reaction amplification followed by Restriction Fragment Length Polymorphism analyses of conserved regions of 16S rDNA of phytoplasmas, or of the Elm yellows group-specific non ribosomal DNA fragment FD9. Potential vectors were searched among leafhoppers and planthoppers trapped in conservatories and tested for the presence of phytoplasma in their body. Sanitation of multiplication material was experimented using soaking of dormant cuttings and branches in hot water, according to the method devised for destruction of phytoplasma in grapevine multiplication material. Phytoplasmas detected in a number of the elm clones held in the conservatories and in several forest or hedgerow elm trees, showed some diversity, according to restriction analyses of the FD9 fragment. Both American and European types were characterized. Four leaf- and planthopper species were found to carry an EY phytoplasma. Plants grown from cuttings taken from EY-infected clones and soaked in hot water (50 °C, 45 mn) never developed symptoms and tested phytoplasma negative. Most of untreated control plants were all symptomatic and positive. In the future, Elm yellows phytoplasma should be carefully checked, especially in sensitive cultivars. More studies of EY phytoplasma variability and potential vectors and the assessment of routine use of hot water therapy in multiplication of material, should be conducted.

In a temperate, deciduous even-aged forest context we tested two main hypotheses related to the short-term and mid-term response of carabid communities to regeneration felling: 1. The 'perturbation hypothesis': species abundances change in opposite directions between species shortly after felling (maximum 20 years). 2. The 'succession hypothesis': species abundances peak, or bottom out, at different silvicultural stages depending on the species (up to 100 years). Our results confirmed the two hypotheses. Moreover, the species that were significantly affected negatively in the short term by the regeneration felling (especially Carabus nemoralis and C. violaceus) increased in abundance along the first 100 years of the silvicultural cycle, suggesting that the regeneration felling did not have a detrimental effect on carabid communities on a 100-year time scale.

The recent development of individual based and spatially explicit models raises the question of how to simulate relevant initial states for these models, and more particularly how to simulate realistic spatial structures. This is especially true for forest stand modelling.In this paper, we first review briefly the main simple steps in the simulation of forest stands with realistic spatial structure : (i) spatial structure analysis and ecological interpretation, (ii) expert simulation through classical point processes and ad hoc values of the parameters, and (iii) precise fitting of a spatial structure model using L(r) and L12(r) functions as criterion. We illustrate the advantages and limits of these steps on a real forest stand in mixed Oak - Scots pine forest near Orléans (France).We then propose a specific method - a mimetic point process - in order to simulate spatial structures similar to real patterns. This point process is based on a generalised Gibbs process, whose global cost function directly depends on the difference between the real measured values of L(r) and L12(r) functions, and the corresponding values computed on the simulated pattern at each iteration of the algorithm. We applied this method on a mixed Oak - Scots pine forest stand, and thus obtained an improved simulated pattern, that can be used as initial state for individual based forest growth models.We finally discuss the limits of this method, and its possible, Le développement récent des modèles individus-centrés spatialement explicites pose de nouvelles questions sur les méthodes de simulation des états initiaux de ces modèles, et plus particulièrement : comment simuler des structure spatiales réalistes. C'est tout particulièrement vrai pour les modèles forestiers. Dans cet article, nous proposons tout d'abord une revue bibliographique des principales méthodes de simulation de peuplements forestiers : (i) l'analyse et l'interprétation écologique de la structure spatiale, (ii) la simulation par expertise, et (iii) l'ajustement de modèles de structure spatiale en utilisant les fonctions L(r) et L12(r) comme critère d'ajustement. Nous illustrons les avantages et les limites de ces méthodes sur un dispositif expérimental en forêt mélangée Chêne - Pin sylvestre dans la forêt d'Orléans.Nous proposons ensuite une méthode spécifique - un processus mimétique - pour simuler des structures spatiales similaires à des structures réelles. Ce processus est basé sur un processus de Gibbs généralisé dont la fonction de coût total dépend directement de la distance entre les valeurs réelles des fonctions L(r) et L12(r) et les valeurs simulées à chaque itération de l'algorithme. Nous avons appliqué cette méthode sur un peuplement mélangé Chêne - Pin sylvestre, et avons obtenu un peuplement simulé plus réaliste, qui peut être utilisé comme état initial pour un modèle forestier individus-centré.Nous discutons enfin des limites de cette méthode, et de son intérêt pour faciliter le transfert des modèles vers les gestionnaires forestiers.

Seed moisture is a key factor influencing seed quality and an continual challenge for forest seed industry. Moisture content (MC) is the most common procedure used to assess moisture of forest seeds; for a given species, the range of optimal water content for storage has been defined both by know-how and conducting tests. However, this approach is not always reliable because it does not take into account the chemical properties of water remaining in dried materials. On the contrary, the concept of activity of water (Aw) quantifies the vapour pressure generated by the moisture present in hygroscopic products like organic substances. It is known as the chemical potential of water. Aw has been widely used for decades by food industry. In this discipline it is very well-known that the reactivity and depreciating ability of hydrolytic reactions, enzymes activity, lipid oxidation or biotic agents growth are dependent on Aw rather than on MC. Consequently, Aw is more consistent to define stability moisture for organic materials preservation. The relationship between Aw and MC is pictured by the sorption/desorption isotherm. This connection is rather stable for standardized organic materials like sugars or flours where it is possible to use equally MC or Aw for moisture assessment. Forest seeds are picked from natural stands or seed orchards where a high genetic diversity is sought after. The combination of genetic and environmental factors results in unpredictable seed characteristics. The R&D project we carry out in cooperation with French forest seed companies Vilmorin and ONF aims to: a)the experimental construction of sorption isotherms of different seed lots to demonstrate the consequent variability among different seed lots for a given species, b)calculate the water activity of greater stability on the basis of desorption isotherms and in accordance with bibliographic references, c)demonstrate the effectiveness of water activity assessment versus moisture content evaluation d)finally, to transfer the Aw technique to ONF and Vilmorin for seed moisture control. Aw applied to forest seeds moisture management is now regularly being used by Vilmorin and on the way to be by ONF.

By creating patchy open areas rich in dead wood in the forest mosaic, windstorm is a major natural disturbance in temperate forests.This paper deals with the impact of the storm Lothar (in December 1999) on saproxylic beetle diversity in managed oak-hornbeam forests in the Brie region (France). Were there short-term gap effects and gap size effects on saproxylic beetle abundance, richness and assemblage composition in uncleared gaps in 2001? Do saproxylic assemblages differ in natural openings and in man-made fellings?Window flight traps were used to sample beetles moving through the air. Beetle assemblages were compared in 24 unlogged windthrow gaps (ranging from 0.1 to 3.3 ha in area), in 14 closed-forest paired controls and in 12 open stands (seed cuts and sapling stands). We sampled 33,799 saproxylic beetles (including 24,116 scolytids), that belong to 32 families or subfamilies and 185 species.Shortly after the disturbance, the abundance of saproxylic beetles did not vary in gaps compared to controls, but the species composition was significantly affected. The cumulative richness of saproxylic species (except scolytids) increased in the gaps. About 15 species (mainly sapro-xylophagous taxa) were characteristic of closed forest and strongly decreased in the gaps, whereas more than 30 species were typical of gaps (mainly pioneer xylophages dependant on fresh, sun-exposed dead wood; but also floricolous species or subcorticolous predators). Saproxylic species were more numerous in gaps than in open stands. Moreover, natural gaps exhibited more characteristic taxa than man-made fellings.Over the whole forest, gaps increase the gamma diversity. The maintenance of unlogged gaps and the partial salvaging of others are discussed as forest management opportunities.

International audience; This paper reviews the effects that windstorm-induced drastic changes (micro-climate, soil, vegetation, and ground structural heterogeneity) have on forest insect communities. In the current context of shady and CWD-deprived managed forests, windthrow gaps act as regional biodiversity hotspots by maintaining habitat continuity in a mosaic landscape, and by facilitating the breeding and population growth of clearing specialists and saproxylic species. Windthrow gaps are dead-wood islands where forest protection and habitat conservation goals may stand against each other. Besides the quantitative effect of dead wood on bark beetle outbreaks and saproxylic diversity, the latter is favoured by key dead-wood micro-habitats such as large logs, snags and sun-exposed coarse woody debris. The role of natural enemies and sanitation operations in regulating pest outbreaks is discussed. Heterogeneous openings provide many micro-habitats favouring flower-visiting insects, phytophages on saplings, on fallen tree crowns, and on diverse understory flora, as well as ground insects on specific micro-sites.

The 2003 drought impacted seriously forest ecosystems but the consequences on biodiversity were largely missed due to the lack of long-term monitoring data. This presentation reviews what we know about the consequences of droughts on (mainly temperate) forest biodiversity from observational and experimental data (mechanisms, life-history traits conferring either drought resistance or drought avoidance, potential consequences on forest ecosystem functioning) and what the research needs are.

This text describes a concrete example of a partnership between forest scientists and managers to build a national directive in forest policy. We are presenting an example of current cooperation between scientists from the Cemagref(French Institute for Agricultural and Environmental Engineering Research) and forest managers from the Office National des Forêts (French national forest service), initiated to update the ONF national directive concerning biodiversity in managed forests (1993).

International audience; Cryopreservation of a core collection of 444 elm (Ulmus spp.) clones in liquid nitrogen was carried out by two laboratories participating in a European project of conservation of elm genetic resources. Plant material, collected in nine European countries, represented a large sample of the genetic diversity within three European elm species and their hybrids. The cryopreservation technique used in both laboratories involved the stepwise freezing of cryotubes containing dormant buds. Comparisons with fresh buds showed that the cryopreservation treatment had no negative effect on the viability and regrowth potential of frozen buds. Tests on a random sample of 26 clones showed that direct regrowth of cryopreserved buds (i.e., through propagation by microcuttings) of Ulmus minor and Ulmus laevis was possible; conversely, Ulmus glabra could only be regrown through micrografting. Most thawed explants from all 26 clones survived through the whole cultivation phase and were successfully transferred to the field. A calculation of costs indicates that cryopreservation of elm buds is economically competitive to field clonal archives.; Deux laboratoires ont réalisé conjointement la cryoconservation d'un noyau (core collection) de 444 clones issu de la collection d'orme (Ulmus sp.) réunis dans le cadre d'un projet européen de conservation des ressources génétiques. Le matériel végétal collecté dans 9 pays européens est représentatif de la diversité génétique naturelle de 3 espèces européennes d'orme et de leurs hybrides. La technique de cryoconservation utilisée est basée sur la descente progressive en température de cryotubes contenant des bourgeons dormants. La comparaison avec des bourgeons en végétation a établi que la technique utilisée n'a pas d'effet délétère sur la viabilité et le potentiel de reprise de croissance des bourgeons congelés. Des tests réalisés sur un échantillon aléatoire de 26 clones montrent que la réactivation de bourgeons cryoconservés d' U. minor et U. laevis est possible par microbouturage direct; contrairement à U. glabra qui ne peut être réactivé que par microgreffage. La plupart des explants dégelés ont produit des plantes transférées avec succès en parcelles expérimentales pour l'ensemble des 26 clones. Un calcul de coût montre que la cryoconservation de bourgeons d'orme est économiquement compétitive en comparaison avec la conservation au champ.

Monitoring of biodiversity as a whole is impossible. Monitoring parts of biodiversity is welcome. Indicators are a good complement to monitoring, provided their quality has been tested.

The main point of this contribution is that interaction between scientists and decision makers will be improved if it centers around (i) shared objectives and language; (ii) a contact with the reality being managed: data; (iii) with the objective of possible future reactions and a common learning; and (iv) in an opened process.