ALBERT

Description:   • Key message This document provides valuable environmental information about a triplets’ essay of Scots pine and Maritime pine in Spain. The dataset characterizes the soil profile (physicochemical parameters of organic and mineral horizons), climate, physiography, understory and overstory. Dataset access is at10.5281/zenodo.4384530and associated metadata is available athttps://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/21cca830-daf9-4913-9b5b-a185d77943d5

Description: •Key message We developed a dataset of the potential distribution of seven ecologically and economically important tree species of Europe in terms of their climatic suitability with an ensemble approach while accounting for uncertainty due to model algorithms. The dataset was documented following the ODMAP protocol to ensure reproducibility. Our maps are input data in a decision support tool “SusSelect” which predicts the vulnerability of forest trees in climate change and recommends adapted planting material. Dataset access is at https://doi.org/10.5281/zenodo.3686918. Associated metadata are available at https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/fe79a36d-6db8-4a87-8a9f-c72a572b87e8.

Description: Gut microorganisms are crucial for many biological functions playing a pivotal role in the host’s well-being. We studied gut bacterial community structure of marine iguana populations across the Galápagos archipelago. Marine iguanas depend heavily on their specialized gut microbiome for the digestion of dietary algae, a resource whose growth was strongly reduced by severe “El Niño”-related climatic fluctuations in 2015/2016. As a consequence, marine iguana populations showed signs of starvation as expressed by a poor body condition. Body condition indices (BCI) varied between island populations indicating that food resources (i.e., algae) are affected differently across the archipelago during ‘El Niño’ events. Though this event impacted food availability for marine iguanas, we found that reductions in body condition due to “El Niño”-related starvation did not result in differences in bacterial gut community structure. Species richness of gut microorganisms was instead correlated with levels of neutral genetic diversity in the distinct host populations. Our data suggest that marine iguana populations with a higher level of gene diversity and allelic richness may harbor a more diverse gut microbiome than those populations with lower genetic diversity. Since low values of these diversity parameters usually correlate with small census and effective population sizes, we use our results to propose a novel hypothesis according to which small and genetically less diverse host populations might be characterized by less diverse microbiomes. Whether such genetically depauperate populations may experience additional threats from reduced dietary flexibility due to a limited intestinal microbiome is currently unclear and calls for further investigation.

Description: • Key message Ash dieback decreases individual reproductive success of ash trees leaving healthy ash overrepresented as seed and pollen parents for next-generation seedlings. Substantial gene flow over hundreds of meters combined with superior fertility of healthy trees creates optimism for the species’ future in European forests. • Context Hymenoscyphus fraxineus is causing high mortality in European ash (Fraxinus excelsior L.). Due to inheritable resistance to the pathogen, natural selection is likely to act in favour of improved resistance in ash forests following natural regeneration. Still, the frequency of healthy trees is low, and the effect of natural selection will depend on survival, reproductive success and the dispersal capacity of healthy trees under natural conditions. • Aims We aim to test whether healthy trees contribute more to the next generation and to infer their potential for dispersing progenies across the forested landscape. • Methods Using parentage modelling, we estimate mating parameters and dispersal distances of seeds and pollen and compare realised reproductive success of healthy trees to that of unhealthy ones. • Results Healthy trees are overrepresented as the parents of randomly sampled seeds and seedlings in the forest, although that is more pronounced on the female side. We observe long dispersal events and estimate the mean seed and pollen dispersal distances as 67 m and 347 m, respectively. • Conclusion Variation in reproductive success results in selection in favour of lowered susceptibility to ash dieback. The large dispersal capacity decreases the risk of genetic bottlenecks and inbreeding and allows resistant trees to disperse their genes into the neighbourhoods of substantial sizes.

Description: • Key message Wavy grain, a rare figure type of wood, leads to highly priced timber in Acer pseudoplatanus L. The influence of this trait on growth performance and its causes are not known. Analyzed wavy and straight grain sycamore maple progenies show comparable growth performance in a field trial. Stability of wavy grain after vegetative propagation is confirmed and genetic inheritance indicated. • Context Wavy grain is a rare figure type of wood resulting from undulating fiber growth that leads to a decorative and highly priced timber in Acer pseudoplatanus L. with top positions on auction sales. Nevertheless, neither the influence of this trait on growth performance is known, nor have the causes been disentangled. • Aims Our objectives were to find out if wavy grain figure influences growth parameters essential for log quality and to gain insight into the causes of wavy grain by the analysis of a progeny trial and a seed orchard. • Methods In a progeny trial with 30-year-old F-1-offspring from selected wavy grained and straight grained trees, trunk diameter, tree height, and trunk shape were evaluated. Additionally, 21 trees of the trial and selected plus tree-grafts of a seed orchard were felled and analyzed for occurrence and intensity of wavy grain structure. • Results No effect of the wavy and straight grain parentage on growth was observed in the progeny trial. Of the felled trees, over 30% showed evidence of wavy grain compared to rare occurrence in natural stands. Wood structure analysis of plus tree scions confirmed the stability of wavy grain after vegetative propagation. • Conclusion Wavy grain seems to be genetically inherited, and there seems to be no statistically significant difference in commercially relevant traits in the progeny. This highlights the value of including wavy grain as a desired attribute in breeding systems of maple.

Description: • Key message The browsing level of oak (Quercus petraea and Quercus robur) and fir (Abies alba) provided only a rough estimate of the expected regeneration success. Thus, it cannot be recommended as a standard measurement to predict forest development, unless the number of saplings and the height of those saplings are considered. • Context Browsing by large herbivores may affect regeneration success and forest development, with an impact that lasts for decades. • Aims Whether the browsing level of a tree species can be used in forestry as a standard measure to assess whether the target values (for instance regeneration success) of highly selected tree species, such as oak (Quercus petraea (Mattuschka) Liebl., Quercus robur (L.)) and fir (Abies alba (Mill.)), will be reached is unclear and need specification. • Methods In this study, 985 sampling plots (10 m2) in Southern Germany (Baden-Württemberg) containing browsed and unbrowsed oak and fir-saplings were analysed. Both the browsing level and a measure of the expected regeneration success that considered not only the sapling density but also different height classes (≤ 20 cm; 21–50 cm; 51–130 cm) were calculated. • Results The use of the browsing level as a proxy for the expected regeneration success was statistically only partly justified. For fir the relationship between browsing level and expected regeneration success became even weaker for a new indicator variable which considers two height classes rather than one class for saplings exceeding 50 cm (51–80 cm and 81–130 cm). • Conclusion According to these results, the browsing level cannot be recommended as a standard measurement and/or predictor of damage, unless the number of saplings and the height of those saplings are considered. Thus, in efforts to mitigate conflicts between foresters and hunters, a measurement is needed that addresses the successful establishment of a sufficient number of trees despite browsing, rather than the browsing of trees alone.

Description: Context Black poplar (Populus nigra L.) is a keystone species of European riparian ecosystems that has been negatively impacted by riverside urbanization for centuries. Consequently, it has become an endangered tree species in many European countries. The establishment of a suitable rescue plan of the remaining black poplar forest stands requires a preliminary knowledge about the distribution of genetic variation among species populations. However, for some parts of the P. nigra distribution in Europe, the genetic resources and demographic history remain poorly recognized. Aims Here, we present the first study on identifying and characterizing the genetic resources of black poplar from the Oder valley in Poland. This study (1) assessed the genetic variability and effective population size of populations and (2) examined whether gene flow is limited by distance or there is a single migrant pool along the studied river system. Methods A total of 582 poplar trees derived from nine black poplar populations were investigated with nuclear microsatellite markers. Results (1) The allelic richness and heterozygosity level were high and comparable between populations. (2) The genetic structure of the studied poplar stands was not homogenous. (3) The signatures of past bottlenecks were detected. Conclusion Our study (1) provides evidence for genetic substructuring of natural black poplar populations from the studied river catchment, which is not a frequent phenomenon reported for this species in Europe, and (2) indicates which poplar stands may serve as new genetic conservation units (GCUs) of this species in Europe. Key message The genetic resources of black poplar in the Oder River valley are still substantial compared to those reported for rivers in Western Europe. On the other hand, clear signals of isolation by distance and genetic erosion reflected in small effective population sizes and high spatial genetic structure of the analyzed populations were detected. Based on these findings, we recommend the in situ and ex situ conservation strategies for conserving and restoring the genetic resources of black poplar populations in this strongly transformed by human river valley ecosystem.

Description: • Key message Errors in forest stand attributes can lead to sub-optimal management prescriptions concerning the set management objectives. When the objective is net present value, errors in mean diameter result in greater losses than similar errors in basal area, and underestimation greater losses than overestimation. • Context Errors in forest inventory data can cause inoptimality losses in the objectives set to forest management. Losses occur when the forest is treated with management prescriptions that are optimal for erroneous data but not for correct data. • Aims We evaluate the effect of varying levels of errors in basal area and mean diameter on the inoptimality losses. • Methods Errors from 20% of overestimation to 20% of underestimation were simulated in basal area and mean diameter. For each stand, the management prescription that maximized the net present value was selected with and without errors. The inoptimality losses were calculated for different error levels. • Results The tested error levels resulted in inoptimality losses of 0.11–3.01%. Errors in mean diameter increased inoptimality losses more than similar relative errors in basal area. Simultaneous underestimation of basal area and mean diameter led to greater inoptimality losses than simultaneous overestimation of these attributes. • Conclusion If the forest is considered as an investment, using inventory data where basal area and mean diameter are underestimated causes greater losses compared with data where these attributes are overestimated. Errors in mean diameter are more important than similar errors in the basal area. Large errors in basal area and mean diameter should be avoided especially in stands where the basal area is high.

Description: • Key message Invasive tree species alter taxonomic diversity and functioning of forest shrub layers: Prunus serotina increases shrub layer biomass two to three times but decreases its biodiversity, Robinia pseudoacacia slightly increases shrub layer biomass and has no effect on its biodiversity, while Quercus rubra both biomass and biodiversity of the shrub layer. • Context Although the impact of invasive trees on understory biodiversity is known, very little data exist about their influence on shrub layer biodiversity and productivity. • Aims To assess impacts of Prunus serotina Ehrh., Quercus rubra L., and Robinia pseudoacacia L. on shrub layer aboveground biomass, species composition, and alpha diversity. • Methods We measured stand structures in a set of 168 study plots established in Wielkopolski National Park (W Poland), and we compared biomass and diversity metrics using generalized mixed-effects linear models. • Results We found the lowest aboveground biomass of shrub layers in Q. rubra forests. P. sylvestris forests invaded by P. serotina had two to three times higher aboveground biomass than non-invaded forests. R. pseudoacacia forests had 27.8% higher shrub layer biomass than Quercus-Acer-Tilia forests. We found negative impacts of Q. rubra and negligible impacts of R. pseudoacacia on shrub layer alpha diversity metrics. However, the effect of Q. rubra was similar to native F. sylvatica. P. serotina negatively affected functional diversity, but its effects were lower in rich P. sylvestris forests than in poor P. sylvestris forests. • Conclusion The introduction of alien tree species alters ecosystem services and species diversity of shrub layers. The direction and magnitude of these alterations are alien species-specific and context-dependent. Therefore, their management should account for their impacts.

Description: Many laboratory experiments demonstrate how orb-web spiders change the architecture of their webs in response to prey, surroundings and wind loading. The overall shape of the web and a range of other web parameters are determined by frame and anchor threads. In the wild, unlike the lab, the anchor threads are attached to branches and leaves that are not stationary but move, which affects the thread tension field. Here we experimentally test the effect of a moving support structure on the construction behaviour and web-parameters of the garden cross spider Araneus diadematus. We found no significant differences in building behaviour between rigid and moving anchors in total time spent and total distance covered nor in the percentage of the total time spent and distance covered to build the three major web components: radials, auxiliary and capture spirals. Moreover, measured key parameters of web-geometry were equally unaffected. These results call for re-evaluation of common understanding of spider webs as thread tensions are often considered to be a major factor guiding the spider during construction and web-operation.

Description: Key message We present a structured and curated database covering 21 years of LFMC measurements in the Catalan region, along with an associated R package to manage updates and facilitate quality processing and visualisation. The data set provides valuable information to study plant responses to drought and improve fire danger prediction. Dataset access is at10.5281/zenodo.4675335, and associated metadata are available athttps://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/583fdbae-3200-4fa7-877c-54df0e6c5542.

Description: Key message The size of the structural components of the root–pit–mound complex was crucial for high moss species richness. Root plates, pits, and mounds were similar in terms of moss species composition, which was mostly determined by forest type. Context Uprooted trees may be colonized by different terricolous mosses including common species and specialists. Aims The main aim of the present study was to analyze the relative effects of tree uprooting on mosses. Methods We used the parametric ZIGLMM and GLMM models to explain the richness and abundance of the moss species and double constrained correspondence analysis (dc-CA) to analyze species composition. Results The size of components of RPM complexes had a positive effect on moss species richness. The species cover of mosses was positively correlated with elevation. Species richness was partly dependent on forest type and species cover on component type and age of the RPM complex. The most important factor diversifying species composition was the type of forest. Species traits were also related to forest communities. Conclusion Uprooted trees are worth keeping in forest community, especially large ones. Moreover, the conservation value of uprooted trees in woodlands is higher if they are dispersed in different forest types.

Description: Urbanisation is proceeding at an alarming rate which forces wildlife to either retreat from urban areas or cope with novel stressors linked to human presence and activities. For example, urban stressors like anthropogenic noise, artificial light at night and chemical pollution can have severe impacts on the physiology of wildlife (and humans), in particular the immune system and antioxidant defences. These physiological systems are important to combat and reduce the severity of parasitic infections, which are common among wild animals. One question that then arises is whether urban-dwelling animals, whose immune and antioxidant system are already challenged by the urban stressors, are more susceptible to parasitic infections. To assess this, we studied nestlings of Eurasian kestrels (Falco tinnunculus) in Vienna, Austria, during 2015 and 2017. We measured biomarkers of innate immune function, oxidative stress and body mass index and ectoparasite infection intensity in 143 nestlings (from 56 nests) along an urban gradient. Nestlings in more urbanised areas had overall fewer ectoparasites, lower haemolysis (complement activity) and lower body mass index compared to nestlings in less urbanised areas. None of the other immune or oxidative stress markers were associated with the urban gradient. Despite some non-significant results, our data still suggest that kestrel nestlings experience some level of reduced physiological health, perhaps as a consequence of exposure to more urban stressors or altered prey availability in inner-city districts even though they had an overall lower ectoparasite burden in these heavily urbanised areas.

Description: Key message Model simulation results suggest that forests in the Sierra Nevada mountains of California will tend to increase in density and basal area in the absence of fire over the next century, and that climate change will favor increases in drought-tolerant species. Context Climate change is projected to intensify the natural summer drought period for Mediterranean-climate forests. Such changes may increase tree mortality, change species interactions and composition, and impact ecosystem services. Aims To parameterize SORTIE-ND, an individual-based, spatially explicit forest model, for forests in the Sierra Nevada, and to model forest responses to climate change. Methods We use 3 downscaled GCM projections (RCP 8.5) to project forest dynamics for 7 sites at different elevations. Results Basal area and stem density tended to increase in the absence of fire. Climate change effects differed by species, with more drought-tolerant species such as Jeffrey pine (Pinus jeffreyi A.Murray bis) and black oak (Quercus kelloggii Newb.) exhibiting increases in basal area and/or density. Conclusion Increasing forest density may favor carbon sequestration but could increase the risk of high-severity fires. Future analyses should include improved parameterization of reproduction and interactions of disturbance with climate effects.

Description: Chemical communication plays a fundamental role in many aspects of an animal’s life from assessing habitat quality to finding mating partners. Behavioural observations show that chemical communication likewise plays an important role in spiders, but the contexts and the substances involved are little explored. Here, we investigate the chemical communication in the garden cross spider Araneus diadematus (Clerck, 1757) between and within the sexes. Using choice trials, we demonstrate that males are attracted to odours of adult females, but not to those of subadult females. Our data further suggest that adult females avoid odours of conspecific adult females, possibly in order to reduce reproductive competition with other females. Cuticle and silk extracts as well as headspace samples of subadult and adult virgin females were analysed via GC–MS. Available candidate compounds for the female sex pheromone were tested via electroantennography on palps (electropalpography) of adult virgin females and on females in behavioural trials. We propose sulcatone (6-methyl-5-hepten-2-one) as a candidate substance for the female volatile pheromone and several long-chained alkanes and alcohols as candidates for contact pheromones. Apart from demonstrating that attraction of males to females depends on the latter’s developmental stage, our study suggests that pheromones can also play an important role between females, an aspect that requires further attention.

Description: Key message New technologies can take us towards real precision forestry: the terrestrial single-photon avalanche diode (SPAD) light detection and ranging (LiDAR) has a great potential to outperform conventional linear mode LiDARs in measuring tree parameters at the stand level. Context Precision forestry together with new sensor technologies implies Digital Forest Inventories for estimation of volume and quality of trees in a stand. Aims This study compared commercial LiDAR, new prototype SPAD LiDAR, and manual methods for measuring tree quality attributes, i.e., diameter at breast height (DBH) and trunk curvature in the forest stand. Methods We measured 7 Scots pine trees (Pinus sylvestris) with commercial LiDAR (Zeb Horizon by GeoSLAM), prototype SPAD LiDAR, and manual devices. We compared manual measurements to the DBH and curvature values estimated based on LiDAR data. We also scanned a densely branched Picea abies to compare penetrability of the LiDARs and detectability of the obstructed trunk. Results The DBH values deviated 1–3 cm correlating to the specified accuracies of the employed devices, showing close to acceptable results. The curvature values deviated 1–6 cm implying distorted range measurements from the top part of the trunks and inaccurate manual measurement method, leaving space for improvement. The most important finding was that the SPAD LiDAR outperformed conventional LiDAR in detecting tree stem of the densely branched spruce. Conclusion These results represent preliminary but clear evidence that LiDAR technologies are already close to acceptable level in DBH measurements, but not yet satisfactory for curvature measurements. In addition, terrestrial SPAD LiDAR has a great potential to outperform conventional LiDARs in forest measurements of densely branched trees.

Description: The timing of volatile organic compound (VOC) emission by flowering plants often coincides with pollinator foraging activity. Volatile emission is often considered to be paced by environmental variables, such as light intensity, and/or by circadian rhythmicity. The question arises as to what extent pollinators themselves provide information about their presence, in keeping with their long co-evolution with flowering plants. Bumblebees are electrically charged and provide electrical stimulation when visiting plants, as measured via the depolarisation of electric potential in the stem of flowers. Here we test the hypothesis that the electric charge of foraging bumblebees increases the floral volatile emissions of bee pollinated plants. We investigate the change in VOC emissions of two bee-pollinated plants (Petunia integrifolia and Antirrhinum majus) exposed to the electric charge typical of foraging bumblebees. P. integrifolia slightly increases its emissions of a behaviorally and physiologically active compound in response to visits by foraging bumblebees, presenting on average 121 pC of electric charge. We show that for P. integrifolia, strong electrical stimulation (600–700 pC) promotes increased volatile emissions, but this is not found when using weaker electrical charges more representative of flying pollinators (100 pC). Floral volatile emissions of A. majus were not affected by either strong (600–700 pC) or weak electric charges (100 pC). This study opens a new area of research whereby the electrical charge of flying insects may provide information to plants on the presence and phenology of their pollinators. As a form of electroreception, this sensory process would bear adaptive value, enabling plants to better ensure that their attractive chemical messages are released when a potential recipient is present.

Description: Diminishing prospects for environmental preservation under climate change are intensifying efforts to boost capture, storage and sequestration (long-term burial) of carbon. However, as Earth’s biological carbon sinks also shrink, remediation has become a key part of the narrative for terrestrial ecosystems. In contrast, blue carbon on polar continental shelves have stronger pathways to sequestration and have increased with climate-forced marine ice losses—becoming the largest known natural negative feedback on climate change. Here we explore the size and complex dynamics of blue carbon gains with spatiotemporal changes in sea ice (60–100 MtCyear−1), ice shelves (4–40 MtCyear−1 = giant iceberg generation) and glacier retreat (

Description: Key Message We provide phenotypic and genotypic data for a progeny trial of 5813 European beech seedlings, originating from 60 open-pollinated families collected at three altitudes (1020 m; 1140 m, 1340 m) on Mont Ventoux (44° 11′ N; 17° 5′ E).

Description: Key message Climate-warming related replacement of beech by oak forests in the course of natural forest succession or silvicultural decisions may considerably reduce ecosystem carbon storage of central European woodlands. Context Climate warming may change the carbon (C) storage in forest biomass and soil through future shifts in tree species composition. With a projected warming by 2–3 K over the twenty-first century, silvicultural adaptation measures and natural succession might lead to the replacement of European beech forests by thermophilic oak forests in drought- and heat-affected regions of central and south-eastern Europe, but the consequences for ecosystem C storage of this species shift are not clear. Aims To quantify the change in C storage in biomass and soil with a shift from beech (Fagus sylvatica) to oak forest (Quercus petraea, Q. frainetto, Q. cerris), we measured the aboveground biomass (AGC) and soil C pools (SOC). Methods AGC pools and SOC stocks to − 100 cm depth were calculated from forest inventory and volume-related SOC content data for beech, mixed beech-oak and oak forests in three transects in the natural beech-oak ecotone of western Romania, where beech occurs at its heat- and drought-induced distribution limit. Results From the cooler, more humid beech forests to the warmer, more xeric oak forests, which are 1–2 K warmer, AGC and SOC pools decreased by about 22% (40 Mg C ha−1) and 20% (17 Mg C ha−1), respectively. The likely main drivers are indirect temperature effects acting through tree species and management in the case of AGC, but direct temperature effects for SOC. Conclusion If drought- and heat-affected beech forests in Central Europe are replaced by thermophilic oak forests in future, this will lead to carbon losses of ~ 50–60 Mg ha−1, thus reducing ecosystem carbon storage substantially.

Description: Key message Pollination is a key step for fruit production. To provide a tool for future in-depth analysis of pollination in chestnut, we describe in detail a chestnut orchard (location, genotype, phenotype and seed-set of all trees). Context Chestnuts, which are insect-pollinated trees, have been massively planted around the world for nut production. Orchards are planted with clonal varieties selected from crosses between the European chestnuts (Castanea sativa) and Japanese chestnuts (C. crenata) or Chinese chestnuts (C. mollissima) because these two last species are tolerant to blight and ink diseases. Aims To characterize chestnut genetic resources and accurately model male and female fitness as well as pollen exchanges in orchards, we characterized all chestnuts of the INRAE chestnut germplasm collection located near Bordeaux (France). Methods All chestnut trees were geolocated and genotyped using 79 SNP and 98 SSR loci. We scored their flowering phenology using chestnut BBCH scale and precisely described their phenotype (height, diameter a breast height (DBH), canopy diameter…), their capacity to produce pollen (flower type, catkins length…) and their fruit production (number of burrs, seed-set…). Results We geolocated 275 trees and genotyped 273 of them. We identified 115 unique genotypes and assigned each genotype to species. To assess phenology, we evaluated 244 trees twice a week, for 6 weeks from early June to mid-July. We also described tree phenotypes with 11 variables, pollen production with 5 variables and fruit production with 3 variables. All measures were recorded in 2018 except seed set that was measured two consecutive years, in 2018 and 2019. Conclusion The data collected is very detailed and allows modelling precisely pollen exchanges between trees. Parts of this data have been successfully published in scientific articles. Data are available at: https://data.inrae.fr/dataset.xhtml?persistentId=doi:10.15454/GSJSWW Associated metadata are available at:https://metadata-afs.nancy.inra.fr/geonetwork/srv/fre/catalog.search#/metadata/02c5ca07-1536-4f89-9a0c-9e8d44a91287

Description: The cosmopolitan water caltrop plant (Trapa natans L.) produces nuts, which in the maturing process develop very hard pericarps. This hardness, together with structure and shape (external spikes) of pericarp and seed, and the water contained in the fruit are responsible for their mechanical properties. This study determined the force needed to break Trapa natans nuts at various drying stages, with tests having been carried out at weekly intervals until the fruit dried completely. The amount of force necessary for cracking nuts at each of the 6 drying stages was determined, as well as the work of crushing calculated until the greatest compressive force (crushing force) was reached. The force needed to rupture the hydrated fruit in the horizontal plane was higher than that necessary for the rupture of dried fruit. The experiment showed that the maximum force needed to crush the fruit was 828.7 N and occurred when crushing the fruit after 2 weeks of drying, while the largest calculated crushing work was 2185.5 mJ for the same fruit. Other strength parameters were introduced to characterize mechanical properties of water caltrop in a more extensive scope. These are hardness defined as a ratio of compressive force increment to strain increment, specific crushing energy defined as a ratio of crushing work to water caltrop’s mass, and unit crashing force defined as a ratio of crushing force to caltrop’s thickness. All these parameters reached their highest mean values for pericarps after 2 weeks of desiccation. Mass measurements were also applied in modelling the desiccation process by the exponential function. The very dense pericarp material, after reaching maturity, slightly changes during drying. It can be used industrially as an extremely durable and biodegradable biological material. Results also suggest that the great evolutionary success of the species may result from the ability of the pericarp to protect its seeds, leading to the spread of this species in aquatic environments.

Description:    Orb-weaving spiders construct webs with adhesive silk but are not trapped by it. Previous studies have attributed this defense to an oily coating on their legs that protects against adhesion or, more recently, to behavioral avoidance of sticky lines. The old evidence is very weak, however, and the behavioral avoidance explanation is inadequate because orb-weavers push with their hind legs against sticky lines hundreds or thousands of times during construction of each orb and are not trapped. Video analyses of behavior and experimental observations of isolated legs pulling away from contact with sticky lines showed that the spider uses three anti-adhesion traits: dense arrays of branched setae on the legs that reduce the area of contact with adhesive material; careful engagement and withdrawal movements of its legs that minimize contact with the adhesive and that avoid pulling against the line itself; and a chemical coating or surface layer that reduces adhesion. Content Type Journal Article Category Short Communication Pages 1-5 DOI 10.1007/s00114-012-0901-9 Authors R. D. Briceño, Escuela de Biología, Universidad de Costa Rica, Ciudad Universitaria, San Pedro, Costa Rica W. G. Eberhard, Escuela de Biología, Universidad de Costa Rica, Ciudad Universitaria, San Pedro, Costa Rica Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description:    Among social insects, maintaining a distinct colony profile allows individuals to distinguish easily between nest mates and non-nest mates. In ants, colony-specific profiles can be encoded within their cuticular hydrocarbons, and these are influenced by both environmental and genetic factors. Using nine monogynous Formica exsecta ant colonies, we studied the stability of their colony-specific profiles at eight time points over a 4-year period. We found no significant directional change in any colony profile, suggesting that genetic factors are maintaining this stability. However, there were significant short-term effects of season that affected all colony profiles in the same direction. Despite these temporal changes, no significant change in the profile variation within colonies was detected: each colony’s profile responded in similar manner between seasons, with nest mates maintaining closely similar profiles, distinct from other colonies. These findings imply that genetic factors may help maintain the long-term stability of colony profile, but environmental factors can influence the profiles over shorter time periods. However, environmental factors do not contribute significantly to the maintenance of diversity among colonies, since all colonies were affected in a similar way. Content Type Journal Article Category Short Communication Pages 1-5 DOI 10.1007/s00114-012-0898-0 Authors S. J. Martin, Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN UK S. Shemilt, Chemical Ecology Group, School of Physical and Geographical Sciences, Keele University, Keele, ST5 5BG UK F. P. Drijfhout, Chemical Ecology Group, School of Physical and Geographical Sciences, Keele University, Keele, ST5 5BG UK Journal Naturwissenschaften Online ISSN 1432-1904 Print ISSN 0028-1042

Description: Context    Soluble organic nitrogen is considered to reflect the effect of forest types on soil nitrogen status. As a major process affecting the soil-soluble organic nitrogen pool, degradation of insoluble organic nitrogen in the production of soluble organic nitrogen is mediated by a suite of soil enzymes. Aims    This study aims to examine soil-soluble organic nitrogen pools and their relationships with the activities of soil enzymes in natural secondary forest stands and adjacent larch plantation stands. Methods    Four pairs of larch plantation stands and secondary forest stands were randomly selected from a mountainous area, and the top 15 cm of the mineral soils were sampled from each field. Results    The soil-soluble organic nitrogen concentrations were up to 2-fold greater in the secondary forest stands than in the larch plantation stands, whereas the ratio of soluble organic nitrogen/total nitrogen was comparable between the two forest types. The concentrations of soluble organic nitrogen were positively correlated with approximately 2-fold differences in urease and protease activities, a 1.2-fold difference in N -acetyl-β-glucosaminidase and a 1.7-fold difference in l -asparaginase between the two forest types. Conclusions    Our results suggest that relationships between soil-soluble organic nitrogen and enzyme activities are independent on sampling time, and that the soil enzyme activities can be used as potential indicators of soil soluble organic nitrogen pools in the temperate forest ecosystem. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-012-0198-z Authors Kai Yang, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Jiaojun Zhu, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Qiaoling Yan, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Jinxin Zhang, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context   The scaling-up approach (which requires the use of individual tree biomass equations and data) is one of the most commonly used methods for estimating stand biomass at a local scale. However, biomass prediction over large management areas requires more efficient methods. Aims   Two methods of estimating aboveground stand biomass were developed and compared: stand biomass equations (SBE) including observed stand variables, and SBE including biomass expansion factors (BEF) and stand volume. Methods   Two types of systems of additive equations were fitted simultaneously for components and total aboveground stand biomass, to ensure additivity. Inherent correlations among biomass components were also taken into account in the fitting process. Results   The systems explained a high percentage of the observed variability. The SBE systems that included observed stand variables provided more accurate estimates than those that included BEF and stand volume. However, the latter were found to be more precise for stem wood and total aboveground biomass prediction. Conclusions   Both approaches provide a direct link between forest inventory data, outputs from whole-stand growth models, and biomass estimates at stand level. Taking into account that the inventory effort is similar for both alternatives, the choice of which to use will depend on the data available and on the relative importance of the biomass components for the end-users. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s13595-012-0191-6 Authors Fernando Castedo-Dorado, Departamento de Ingeniería y Ciencias Agrarias, Universidad de León. Escuela Superior y Técnica de Ingeniería Agraria, Avda. de Astorga s/n, 24400 Ponferrada, León, Spain Esteban Gómez-García, Departamento de Ingeniería Agroforestal, Universidad de Santiago de Compostela. Escuela Politécnica Superior, R/ Benigno Ledo, Campus Universitario, 27002 Lugo, Spain Ulises Diéguez-Aranda, Departamento de Ingeniería Agroforestal, Universidad de Santiago de Compostela. Escuela Politécnica Superior, R/ Benigno Ledo, Campus Universitario, 27002 Lugo, Spain Marcos Barrio-Anta, Departamento de Biología de Organismos y Sistemas, Universidad de Oviedo. Escuela Politécnica de Mieres, C/Gonzalo Gutiérrez Quirós, 33600 Mieres, Asturias, Spain Felipe Crecente-Campo, Departamento de Ingeniería Agroforestal, Universidad de Santiago de Compostela. Escuela Politécnica Superior, R/ Benigno Ledo, Campus Universitario, 27002 Lugo, Spain Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: • Context    There is little information about inter- and intra-specific variation in fuelwood properties of trees/shrubs in West Africa. • Aims    We studied variation in fuelwood properties of Balanites aegyptiaca , Combretum glutinosum , Guiera senegalensis , Piliostigma reticulatum , and Zizyphus mauritiana in the Sahelian and Sudanian ecozones of Mali. • Methods    Trees were sampled on different soil (sandy, sandy/loam, or rocky), land use (parkland agroforest or woodland), and terrain (flat, temporarily flooded, or hill slope) types in five regions extending from the drier eastern to the more humid western parts of Mali. Basic density, volatile matter, fixed carbon, ash content, moisture content, gross calorific value, and fuel value index were measured for each tree and adjusted for tree age. • Results    All fuelwood properties differed significantly among species, but there were significant species by region interactions. Most fuelwood properties of four species differed significantly among regions. Soil and/or land use type had significant effects on a few fuelwood properties of four species. • Conclusion    In general, fuelwood production is recommended in all regions for G. senegalensis , in drier regions for B. aegyptiaca and C. glutinosum , in more humid regions for Z. mauritiana , and on rocky soils for all species. Fuelwood production of P. reticulatum is not recommended. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-012-0195-2 Authors Carmen Sotelo Montes, World Agroforestry Centre (ICRAF), Sahel Office, B. P. E 5118 Bamako, Mali John C. Weber, World Agroforestry Centre (ICRAF), Sahel Office, B. P. E 5118 Bamako, Mali Dimas A. Silva, Universidade Federal do Paraná, Av. Lothário Meissner, 900, CEP: 80270-170 Curitiba, Brazil Clarice Andrade, Universidade Federal do Paraná, Av. Lothário Meissner, 900, CEP: 80270-170 Curitiba, Brazil Graciela I. B. Muñiz, Universidade Federal do Paraná, Av. Lothário Meissner, 900, CEP: 80270-170 Curitiba, Brazil Rosilei A. Garcia, Instituto de Florestas, Departamento de Produtos Florestais, Universidade Federal Rural do Rio de Janeiro, BR 465, km 07, 23890-000, Seropédica, Rio de Janeiro, Brazil Antoine Kalinganire, World Agroforestry Centre (ICRAF), Sahel Office, B. P. E 5118 Bamako, Mali Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context    Fir species are mainly distributed across the high latitudes, preferring cold climates. The phylogeographic origins of those subtropical fir species that occur in low latitudes in southern China remain elusive, as does the nature of any inter-lineage hybridization. Aims    In fir species, mitochondrial DNA (mtDNA) is maternally inherited and chloroplast DNA (cpDNA) is paternally inherited, and the genetic variations in the two make them particularly useful for examining species’ hybridizations and evolutionary histories. Materials and methods    We sequenced four DNA fragments: two of mtDNA and two of cpDNA for 161 individuals from four subtropical endangered fir species ( Abies beshanzuensis , Abies ziyuanensis , Abies yuanbaoshanensis , and Abies fanjingshanensis ) and two more northerly distributed ones ( Abies recurvata and Abies fargesii ) from central and southwest China. Results    Three mitotypes and four chlorotypes were recovered from the four southern species. In most populations, individuals share a single fixed mitotype and chlorotype. Three mitotypes clustered into two distinct clades, each associated with one of the northern species examined. For four chlorotypes, one occurred in A. ziyuanensis , A. beshanzuensis , A. fargesii , and A. recurvata , another in A. ziyuanensis and A. recurvata , the remaining two differed from others by two mutations exclusively in A. fanjingshanenis and A. yuanbaoshanensis. Conclusion    Phylogeographic origins of the subtropical fir species are complex, and genetic admixtures occurred during the evolutionary history of A. ziyuanensis . The genotyped populations further provide basic frames for genetic delimitation and effective conservation of these endangered species in the future. Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s13595-011-0170-3 Authors Yanling Peng, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Shuming Yin, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Jing Wang, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Bin Tian, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Guangpeng Ren, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Qiuhong Guo, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Jianquan Liu, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context and aim    This study aimed to examine the effect of the tension wood G‐layer on the viscoelastic properties of wood. Methods    Tension wood and opposite wood samples were obtained from six French Guianese tropical rainforest species ( Sextonia rubra , Ocotea guyanensis , Inga alba , Tachigali melinoni , Iyranthera sagotiana and Virola michelii ); the tension wood of the former three of these species had a G‐layer, whilst the tension wood from the latter three had no G‐layer. Tensile dynamic mechanical analysis (DMA) was performed on green never dried wood samples in the longitudinal direction with samples submerged in a water bath at a temperature (30°C) and frequency (1 Hz) representative of the conditions experienced by wood within a living tree. Then, DMA was repeated with samples conditioned to an air-dried state. Finally, samples were oven-dried to measure longitudinal shrinkage. Results    Tension wood did not always have a higher longitudinal storage (elastic) modulus than opposite wood from the same tree regardless of the presence or absence of a G‐layer. For the species containing a G‐layer, tension wood had a higher damping coefficient and experienced a greater longitudinal shrinkage upon drying than opposite wood from the same species. No difference was found in damping coefficients between tension wood and opposite wood for the species that had no G‐layer. Conclusion    It is proposed that the different molecular composition of the G-layer matrix has an influence on the viscoelasticity of wood, even if a biomechanical gain is not yet clear. This study shows that rheological properties and longitudinal shrinkage can be used to detect the presence of a G‐layer in tension wood. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-011-0164-1 Authors J. Paul McLean, Laboratoire de Mécanique et Génie Civil (LMGC), Université Montpellier 2, CNRS, Montpellier, France Olivier Arnould, Laboratoire de Mécanique et Génie Civil (LMGC), Université Montpellier 2, CNRS, Montpellier, France Jacques Beauchêne, UMR Ecologie des Forêts de Guyane (ECOFOG), CIRAD, Kourou, French Guiana Bruno Clair, Laboratoire de Mécanique et Génie Civil (LMGC), Université Montpellier 2, CNRS, Montpellier, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context   The past management of Pinus brutia forests in Lebanon has led to diverse stand structures that cannot be easily classified as even-aged (EA) or uneven-aged (UA). Most stands are between these stand types, and they may be called as “semi-even-aged”. This is a very common characteristic throughout the Mediterranean conifer forests and makes the choice between the EA and UA approaches problematic, in both management and modelling. However, previous research has devoted little attention to the performance of growth and yield models when applied to transitional stand structures. Aims   The aim of this study was to find the best modelling approach and to recommend equations for simulating the dynamics of the semi-even-aged P. brutia stands of Lebanon on an individual-tree basis. Methods   Fifty sample plots were measured in Lebanon. Individual-tree growth models were fitted to the whole dataset using either UA or EA modelling approach. Models were also fitted using two sub-samples containing the most EA and the most UA plots. The performance and accuracy of the two modelling approaches were evaluated in all three datasets. Results   The article provides the first complete growth model for uneven-aged P. brutia stands. The EA sub-models presented better statistical fitting. However, the UA sub-models enabled more accurate predictions of wood production and were almost as good as the EA sub-models when predicting stand dynamics of the EA plots. The EA approach provided poor predictions, and the errors were high when it was applied to UA stands. Conclusions   In structurally complex stands, the UA modelling approach is to be preferred since it predicts the whole stand dynamics more accurately and enables simulations of a broader range of silvicultural treatments. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-011-0171-2 Authors Sergio de-Miguel, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Timo Pukkala, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Nabil Assaf, Paris Sorbonne University (Paris IV), 1Rue Victor Cousin, 75005 Paris, France José Antonio Bonet, Centre Tecnològic Forestal de Catalunya (CTFC), Ctra. Sant Llorenç de Morunys, km 2, 25280 Solsona, Spain Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Introduction   The logging of several spruce plantations is planned for the next years in the Eifel National Park (Western Germany). To understand the ecological mechanisms of spontaneous forest regeneration that follows these impacts, it is crucial to investigate the species composition and functional diversity of the buried germinable seeds in those stands. Methods   We analysed the soil seed bank by germination method and characterised germination dynamics and distribution of seedlings throughout the samples according to a sigmoid model and cumulative curves, respectively. To compare the proportions of functional and syntaxonomical groups between seed bank and aboveground vegetation, we applied the Fisher’s exact test. Additionally, we described the spatial distribution of the species in the seed bank according to semivariograms. Results   The studied seed bank reached a density of about 5,300 seed m −2 . Most of the species detected in the seed bank are related to open vegetation, forest fringes and early successional stages of forest regeneration. In spite of a low floristic similarity between seed bank and aboveground vegetation, the functional and syntaxonomical composition is very similar. Further studies considering the distribution of seeds in the soil and the changes of the seed bank composition during the regeneration process are required. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-011-0174-z Authors Miguel Alvarez, INRES-Vegetation Ecology, Rheinische Friedrich-Wilhelms-Universität, Nußallee 9, 53115 Bonn, Germany Katja Seis, Institute of Silviculture, Albert-Ludwigs-Universität, Tennenbacherstr. 4, 79085 Freiburg, Germany Bodo Maria Möseler, INRES-Vegetation Ecology, Rheinische Friedrich-Wilhelms-Universität, Nußallee 9, 53115 Bonn, Germany Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context    Rotation length is known to affect timber quality in many plantation species, but its effect on the properties of Sitka spruce ( Picea sitchensis ) structural timber has not been quantified. Aim    Te purpose of this study was to compare selected wood properties and grade recovery of Sitka spruce structural timber cut from different radial positions within a log reflecting different cambial ages. Methods    Structural timber was sawn from 60 logs harvested from an 83-year-old stand in Great Britain. Five specimens were tested from each log: four from consecutive radial positions out from the pith and the fifth a random selection from outside the innermost 15 rings. Results    Mean modulus of elasticity and bending strength of timber from the outermost radial position were 51% and 41% greater, respectively, than for timber from adjacent to the pith. Wood density differed by 9% between these positions. The amount of distortion (spring, twist and bow), knot frequency and total knot area was significantly higher in timber cut from adjacent to the pith. Conclusion    Whilst longer rotations result in timber with improved mechanical properties and less distortion, economic and windthrow considerations may limit their implementation in Great Britain. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-011-0168-x Authors John R. Moore, Forest Products Research Institute, Edinburgh Napier University, Edinburgh, EH10 5DT UK Andrew J. Lyon, Forest Products Research Institute, Edinburgh Napier University, Edinburgh, EH10 5DT UK Stefan Lehneke, Forest Products Research Institute, Edinburgh Napier University, Edinburgh, EH10 5DT UK Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context    Pinus radiata D. Don is the most widely planted conifer in the Inter-Andean Valleys of Bolivia. However, Bolivia lacks knowledge on stand dynamics and yield prediction of radiata pine, and the particular Bolivian conditions prevent a straightforward application of equations developed elsewhere. Aims    This study developed site index models, individual tree diameter increment models, individual tree height models, and self-thinning models for Bolivian P. radiata plantations. Methods    Dominant height was modeled using the algebraic difference approach. Diameter increment was modeled as a function of tree size, site index, and competition. Individual tree height was modeled as a function of tree diameter, dominant height, and dominant diameter. Self-thinning was modeled as a function of quadratic mean tree diameter. Results    By using the models, it can be calculated that the mean annual increment in volume with the optimal rotation length is less than 10 m 3 ha −1 on poor sites and 25 m 3 ha −1 on the best sites. Rotation lengths that maximize wood production are 25–30 years for very good sites and 35–40 years for poor sites. Conclusion    The models were assembled into a growth and yield simulator, allowing the simulation of stand development and making it possible to predict future yields and to compare alternative management schedules. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-011-0162-3 Authors Gustavo Guzmán, Escuela de Ciencias Forestales, Universidad Mayor de San Simón, Final Av. Atahuallpa s/n, Temporal de Cala Cala, Barrio Prefectural, Cochabamba, Bolivia Timo Pukkala, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Marc Palahí, Mediterranean Regional Office, European Forest Institute, Sant Pau Historic Site, Santa Victoria Pavilion, St. Antoni M. Claret, 167, 08025 Barcelona, Spain Sergio de-Miguel, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context    Turkish red pine ( Pinus brutia Ten.) is widespread in the eastern Mediterranean Basin. In the late 1970s, four common gardens were established along steep altitudinal transects extending from the coast to about 1,200 m in the Taurus Mountains (Antalya, Turkey). Aims    The aim was to study the role of altitude in shaping Turkish red pine genetic diversity and population structure as well as to evaluate the existence of local adaptation along altitudinal gradients in this species. Methods    Genetic diversity and population structure were evaluated in replicated altitudinal gradients using chloroplast microsatellite (cpSSR) markers. Genetic differentiation for neutral markers was compared with quantitative differentiation for growth traits for the same populations evaluated at different altitudes. Results    Genetic differentiation among altitudinal groups was higher than among transects. A high portion of the genetic variance corresponded to families within populations (up to 10.75%). Overall quantitative genetic differentiation ( Q ST ) was higher than molecular differentiation in most test sites for all the traits and ages considered. Conclusion    Turkish red pine shows signatures of local adaptation to environmental gradients related to altitude. For forestry practices, such as selection of seed sources, both altitude and the family level of variation need to be considered. Content Type Journal Article Category Original Paper Pages 1-7 DOI 10.1007/s13595-011-0169-9 Authors Yusuf Kurt, Biology Department, Faculty of Sciences, Akdeniz University, 07058 Antalya, Turkey Santiago C. González-Martínez, Department of Forest Ecology and Genetics, CIFOR-INIA, P.O. Box 8111, 28080 Madrid, Spain Ricardo Alía, Department of Forest Ecology and Genetics, CIFOR-INIA, P.O. Box 8111, 28080 Madrid, Spain Kani Isik, Biology Department, Faculty of Sciences, Akdeniz University, 07058 Antalya, Turkey Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context   Forest scientists build models to simulate stand growth and forests dynamics. Dedicated computer tools are often developed to implement these models in order to run silvicultural scenarios and explore simulation results. Aims   Our objective was to encourage software reuse and simplify model implementation. Methods   The scheme was to develop a framework and methodology allowing to simplify the implementation, integration, simulation and comparison of forest models by providing a set of common and standard tools. Results   Capsis provides an open and modular software architecture based on various components, allowing to run forest growth simulations and display the results. The benefits of this framework are shown with the Samsara2 model, an individual-based and spatialised tree model. Capsis has been used successfully in many similar projects. In addition, the Capsis methodology defines how developers, modellers and end-users may interact. Conclusion   The Capsis framework facilitates collaborative and shared software development. Moreover, it is a powerful way to support scientific animation in the frame of forest science. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s13595-011-0140-9 Authors Samuel Dufour-Kowalski, INRA, UMR931 AMAP, Botany and Computational Plant Architecture, TA A-51/PS2, Boulevard de la Lironde, 34398 Montpellier Cedex 5, France Benoît Courbaud, CEMAGREF, Mountain Ecosystems Research Unit, 2 rue de la Papeterie, 38402 Saint Martin d’Hères, France Philippe Dreyfus, INRA, UR629 URFM, Écologie des Forêts Méditerranéennes, Site Agroparc, Domaine Saint Paul, 84914 Avignon Cedex 9, France Céline Meredieu, INRA, UMR1202 BIOGECO, 69 route d’Arcachon, 33612 Cestas Cedex, France François de Coligny, INRA, UMR931 AMAP, Botany and Computational Plant Architecture, TA A-51/PS2, Boulevard de la Lironde, 34398 Montpellier Cedex 5, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Objectives    We examined canopy gap structure and regeneration patterns at the landscape scale using a combination of remote sensing and field-based surveys. Methods    The study was carried out in the forest reserve of Lom, an old-growth Fagus-Abies-Picea forest located within the Dinaric Alps in the north-western part of Bosnia and Herzegovina. A high-resolution (1-m panchromatic and 4-m multispectral) Kompsat-2 satellite image was orthorectified and classified through an unsupervised pixel-based classification using an artificial neural network method. Results    This approach allowed the identification of 650 canopy gaps, ranging in size from 32 to 1,776 m 2 . Only 20 intermediate to large gaps (〉250 m 2 ) were identified, and they were mainly present near the perimeter of the reserve. The origin of these large openings was associated with past human-caused disturbances or topographic conditions. The species composition of regeneration within large, human-caused gaps differed markedly from small gaps and non-gap sites in the core area of the reserve. Shade-intolerant species dominated the seedling and sapling layers in large openings. The landscape approach employed in this study confirmed the hypothesis that small gaps predominate at Lom, especially within the core area of the reserve. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-011-0177-9 Authors Matteo Garbarino, Department of AGROSELVITER, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Enrico Borgogno Mondino, Department of DEIAFA, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Emanuele Lingua, Department of TESAF, University of Padova, Agripolis, Viale dell’Università 16, 35020 Legnaro, PD, Italy Thomas A. Nagel, Department of Forestry and Renewable Forest Resources, University of Ljubljana, Vecna Pot 83, 1000 Ljubljana, Slovenia Vojislav Dukić, Faculty of Forestry, University of Banja Luka, Vojvode Stepe Stepanovića 75a, 78000 Banja Luka, Republic of Bosnia and Herzegovina Zoran Govedar, Faculty of Forestry, University of Banja Luka, Vojvode Stepe Stepanovića 75a, 78000 Banja Luka, Republic of Bosnia and Herzegovina Renzo Motta, Department of AGROSELVITER, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context   Microfibril angle (MFA) is one of the key determinants of solid timber performance due to its strong influence on the stiffness, strength, shrinkage properties and dimensional stability of wood. Aims   The aim of this study was to develop a model for predicting MFA variation in plantation-grown Scots pine ( Pinus sylvestris L). A specific objective was to quantify the additional influence of growth rate on the radial variation in MFA. Methods   Twenty-three trees were sampled from four mature Scots pine stands in Scotland, UK. Pith-to-bark MFA profiles were obtained on 69 radial samples using scanning X-ray diffractometry. A nonlinear mixed-effects model based on a modified Michaelis–Menten equation was developed using cambial age and annual ring width as explanatory variables. Results   The largest source of variation in MFA (〉90 %) was within trees, while between-tree variation represented just 7 % of the total. Microfibril angle decreased rapidly near the pith before reaching stable values in later annual rings. The effect of ring width on MFA was greater at higher cambial ages. Conclusion   A large proportion of the variation in MFA was explained by the fixed effects of cambial age and annual ring width. The final model is intended for integration into growth, yield and wood quality simulation systems. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-012-0248-6 Authors David Auty, Forest Research, Roslin, Midlothian, EH25 9SY Scotland, UK Barry A. Gardiner, Forest Research, Roslin, Midlothian, EH25 9SY Scotland, UK Alexis Achim, Département des sciences du bois et de la forêt, Université Laval, Québec, G1V 0A6 Canada John R. Moore, Scion (New Zealand Forest Research Institute Limited), Private Bag 3020, Rotorua, 3046 New Zealand Andrew D. Cameron, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UU Scotland, UK Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Description: Context   We investigated the relationships between decay classes, morphological characteristics and chemical compounds in Abies alba Mill. and Fagus sylvatica L. stumps in two forest stands in the central Apennines (Italy). The analysis of deadwood decomposition is important in estimating carbon sequestration potential and carbon residence time in forest ecosystems. In addition, deadwood decomposition affects nutrient cycling and microhabitat distribution. Aims   The overall aim of this study was to investigate the decomposition processes in a mountainous Mediterranean ecosystem, and specifically to assess changes in chemical variables (lignin, cellulose, carbon and nitrogen content) in deadwood during the decomposition process, in relation to decay classes and to the species. Methods   Cross-sections were collected from stumps. Samples were assigned to visually discernible decay classes, and cellulose, lignin and carbon (C) and nitrogen (N) content in relation to total dry mass were analysed during the decay process. Results   Results showed how C/N ratio decreased over decades due to an increase in nitrogen content. On the contrary, carbon concentration in stumps remained substantially stable. Lignin degraded slowly in comparison with cellulose and differences between species were observed. Conclusion   The hypothesis that the conifer species would decompose faster than deciduous species did not prove correct. The slower decay of lignin compared to cellulose suggested that lignin could be an important long-term source of soil organic carbon, and that this process could be greatly affected by forest species mixtures. Finally, decomposition processes in the investigated montane–Mediterranean forests were definitely faster than in the colder climates of northern Europe. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-012-0230-3 Authors F. Lombardi, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy P. Cherubini, Landscape Dynamics Unit—Dendroecology, WSL Swiss Federal Research Institute of Forest, Snow and Landscape, 8903 Birmensdorf, Switzerland R. Tognetti, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy C. Cocozza, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy B. Lasserre, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy M. Marchetti, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560