769 research outputs found

    Effective attraction radius of pheromone traps for Monochamus galloprovincialis

    Get PDF

    Ce que la reconstruction comparative peut apporter Ă  la morphologie constructionnelle. Une cavalcade Ă©tymologique

    Get PDF
    This paper reconsiders the etymology of the lexical units Cat. cavalcar, encavalcar, descavalcar and their cognates, e.g. Span. cabalgar, Port. encavalgar, or It. discavalcare. An etymological cavalcade in the framework of the Dictionnaire Étymologique Roman (DÉRom) yields three Proto-Romance etyma: */ka'βall‑ɪk‑a‑/, */ɪn‑ka'βall‑ɪk‑a‑/, and */dɪs‑ka'βall‑ɪk‑a‑/. These etyma, out of which only the first one presents a correlate in written Latin, owe their existence to the application of comparative reconstruction to the Romance lexicon, the last ones respresenting derivatives from */ka'βall‑ɪk‑a‑/ with the prefixes */ɪn‑/ and */dɪs‑/

    Species variables or environmental variables as indicators of forest biodiversity: a case study using saproxylic beetles in Maritime pine plantations

    Get PDF
    To assess the sustainability of plantation forest management we compare two types of biodiversity indicators. We used the species richness of saproxylic beetles as a case study to test the “species” and “environmental” indicator approaches. We compared single species abundance or occurrence and deadwood volume or diversity as predictor variables. ‱ Beetles were sampled with flight interception traps in 40 Maritime pine plantation stands. The volume and diversity of deadwood was estimated with line intersect and plot sampling in the same stands. Predictive models of species richness were built with simple linear or Partial Least Square regressions. ‱ Deadwood variables appeared to be good predictors of saproxylic beetle richness at the stand-scale with at least 75% of variance explained. Deadwood diversity variables consistently provided better predictive models than volume variables. The best environmental indicator was the diversity of deadwood elements larger than 15 cm in diameter. ‱ By contrast, the use of “species variables” appeared to be less relevant. To reach the quality of prediction obtained with “environmental variables”, the abundance or occurrence of 6 to 7 species – some of which are difficult to identify – had to be used to build the indicator

    Modelling Monochamus galloprovincialis dispersal trajectories across a heterogeneous landscape to optimize monitoring by trapping networks

    Get PDF
    Context 14 The pine wood nematode (PWN), is an invasive species which was introduced into Europe in 15 1999. It represents a major economic and ecological threat to European forests. In Europe, the 16 maritime pine is the main host and Monochamus galloprovinciallis is its only vector. 17 18 Objectives 19 Our goal was to analyze the effect of landscape heterogeneity on the vector’s dispersal. We 20 further aimed at developing a new method to locate the origin of insects captured in a systematic 21 network of pheromone traps. 22 23 Methods 24 A mark-release-recapture experiment was carried out in a heterogeneous landscape combining 25 maritime pine plantations, clear-cuts and isolated patches of broadleaved and mixed forests in 26 the southwest of France. 27 Least-cost path analysis was used to model dispersal trajectories and assign friction values to 28 each land-use type in the landscape. We used the trap’s geographical coordinates, capture levels 29 and mean friction values of neighbouring patches to calculate a weighed barycentre and the 30 position of the release of marked beetlesinfo:eu-repo/semantics/submittedVersio

    Drought and stand susceptibility to attacks by the European spruce bark beetle: A remote sensing approach

    Get PDF
    Several time-series analyses have demonstrated that after extreme summer droughtbark beetle damage increased. However, studies predicting stand susceptibility overlarge spatial extents are limited by technical constraints in obtaining detailed,spatially-explicit data on infestation spot occurrence.2. Using a unique dataset of georeferenced bark beetle infestation data, we testedwhether the spatial variation of local growing conditions of forest stands, topogra-phy, and landscape variables modified the local occurrence ofIps typographusinfes-tations after a severe hot drought in Central Europe.3. Bark beetle infestation occurrence depended on soil-related aridity intensity, eleva-tion, slope, and soil conditions. We showed that elevation interacted with growingconditions and topography. At low elevations, spruce forests growing on flat areasand wetter soils were more sensitive to the infestations. On the contrary, forestson steep slopes and soils with low water availability were rarely attacked. At thelandscape scale, bark beetle damage increased with host tree cover but decreasedwith compositional diversity.4. Our findings are generally consistent with the growth-differentiation balancehypothesis that predicts that trees growing under chronic dry conditions tend to bemore resistant against biotic disturbances.5. Spruce stands at low elevations located in homogeneous landscapes dominated byspruce were those more exposed to bark beetles in the initial phase of a drought-induced outbrea

    La cochenille du pin maritime, Matsuccocus feytaudi, nouvelles données épidémiologiques et perspectives de lutte.

    Get PDF
    La cochenille Matsucoccus feytaudi fait son apparition en Corse en 1994. Depuis, un rĂ©seau de surveillance a Ă©tĂ© mis en place, qui a permis de suivre efficacement l'Ă©volution de la maladie. MĂȘme si les rĂ©sultats en terme de mortalitĂ© ne sont guĂšre encourageants, des solutions de lutte prĂ©ventive semblent se profiler : lutte biologique, Ă©claircie prĂ©ventive, sĂ©lection d'arbres rĂ©sistants..

    Fungal disease incidence along tree diversity gradients depends on latitude in European forests

    Get PDF
    European forests host a diversity of tree species that are increasingly threatened by fungal pathogens, which may have cascading consequences for forest ecosystems and their functioning. Previous experimental studies suggest that foliar and root pathogen abundance and disease severity decrease with increasing tree species diversity, but evidences from natural forests are rare. Here, we tested whether foliar fungal disease incidence was negatively affected by tree species diversity in different forest types across Europe. We measured the foliar fungal disease incidence on 16 different tree species in 209 plots in six European countries, representing a forest-type gradient from the Mediterranean to boreal forests. Forest plots of single species (monoculture plots) and those with different combinations of two to five tree species (mixed species plots) were compared. Specifically, we analyzed the influence of tree species richness, functional type (conifer vs. broadleaved) and phylogenetic diversity on overall fungal disease incidence. The effect of tree species richness on disease incidence varied with latitude and functional type. Disease incidence tended to increase with tree diversity, in particular in northern latitudes. Disease incidence decreased with tree species richness in conifers, but not in broadleaved trees. However, for specific damage symptoms, no tree species richness effects were observed. Although the patterns were weak, susceptibility of forests to disease appears to depend on the forest site and tree type

    Awareness, detection and management of new and emerging tree pests and pathogens in Europe: stakeholders' perspectives

    Get PDF
    Emerging and invasive tree pests and pathogens in Europe are increasing in number and range, having impacts on biodiversity, forest services, ecosystems and human well-being. Stakeholders involved in tree and forest management contribute to the detection and management of new and emerging tree pests and pathogens (PnPs). We surveyed different groups of stakeholders in European countries. The stakeholders were mainly researchers, tree health surveyors and forest managers, as well as forest owners, nurseries, policy-makers, advisors, forestry authorities, NGOs and civil society. We investigated which tools they used to detect and manage PnPs, surveyed their current PnP awareness and knowledge and collated the new and emerging PnP species of concern to them. The 237 respondents were based in 15 European coun-tries, with the majority from the United Kingdom, France and the Czech Republic. There was a strong participation of respondents with a work focus on research and surveying, whereas timber traders and plant importers were less represented. Respondents were surveyed on 18 new, emerging PnPs in Europe and listed an additional 37 pest species and 21 pathogen species as potential future threats. We found that species on EPPO's list of 'priority pests' were better known than those not listed.Stakeholders working in urban environments were more aware of PnPs compared to those working in rural areas. Stakeholders' awareness of PnPs was not related to the number of new, emerging PnP species present in a country. Stakeholders want access to more detection and management tools, including long-term citizen -sci-ence monitoring, maps showing spread and range of new PnPs, pest identification smartphone apps, hand-held detection devices, drone monitoring and eDNA metabarcoding. To help facilitate better forest health across Europe, they called for mixed forest development, reduced nursery stock movement, biosecurity and data sharing amongst organisations. These results indicate that stakeholder knowledge of a few key PnP may be good, but given that the large diversity of threats is so large and future risks unknown, we conclude that multiple and varied methods for generic detection, mitigation and management methods, many in devel-opment, are needed in the hands of stakeholders surveying and managing trees and woodlands in Europe
    • 

    corecore