35 research outputs found
Impact of inundation regime on wild bee assemblages and associated beeâflower networks
International audienceAbstractWild bee assemblages on flood-prone meadows were compared with those on rarely inundated sites along the river Danube in easternmost Lower Austria. We sampled flower-visiting bees on 32 meadows from April to August 2016. Although we recorded more bee individuals on rarely inundated meadows, total bee species richness was higher on regularly flooded meadows and we observed a stronger differentiation diversity of bees among annually flooded meadows. Three network metrics derived from a bipartite plantâbee interaction matrix were unaffected by flooding regime. We conclude that extreme floods, which sporadically affect the investigated habitats, may have a devastating effect on wild bee populations, but communities quickly recover. This resilience surely depends on recolonization from the surrounding landscape, which emphasizes the need to consider community dynamics in highly variable floodplain areas not only locally, but on a landscape scale
Langzeit-Monitoring der Auswirkungen einer Umstellung auf den biologischen Landbau (MBUIL V), Abschlussbericht
Auf einem Ackerbaubetrieb im Marchfeld in Niederösterreich wird seit dem Jahr 2003 eine umfassende Langzeituntersuchung zur Dokumentation und Entwicklung des biologischen Landbaus und agrarökologischer BegleitmaĂnahmen durchgefĂŒhrt (www.mubil.boku.ac.at). In der Projektphase MUBIL V wurden im Jahr 2014 spezifische Themen aus dem Gesamtmonitoring ausgewĂ€hlt und fortgefĂŒhrt. Die Untersuchungen fanden auf Betriebs-, Schlag- und Parzellenebene statt. Die Ziele des Projektes waren: (a) Wissenschaftlich abgesicherte Erkenntnisse ĂŒber das AusmaĂ und die Geschwindigkeit von VerĂ€nderungen der pflanzenbaulichen Entwicklung mit der lĂ€ngerfristigen biologischen Bewirtschaftung zu erhalten. (b) Erkenntnisse ĂŒber die Auswirkungen unterschiedliche DĂŒngungssysteme viehloser und viehhaltender biologischer Bewirtschaftung mithilfe pflanzenbaulicher Untersuchungen ĂŒber vergleichende Versuchsanstellungen zu erlangen. (c) Erkenntnisse ĂŒber die Wirkungen von BlĂŒhstreifen mit unterschiedlichen Ansaatmischungen und PflegemaĂnahmen auf die Wildbienen zu dokumentieren
Dispersal patterns of an introduced wild bee, Megachile sculpturalis Smith, 1853 (Hymenoptera: Megachilidae) in European alpine countries.
Biodiversity monitoring programs are the baseline of species abundancy studies, which in case of introduced species are especially critical. Megachile sculpturalis Smith, 1853 native to Eastern-Asia, constitutes the first ever recorded wild bee species accidently introduced in Europe. Since its first discovery in 2008, M. sculpturalis has been spreading across the continent. By initiating a citizen science monitoring program, we aimed to investigate the occurrence pattern of M. sculpturalis. Within only two years after starting the project, 111 new reports from Switzerland, Liechtenstein and Austria were recorded. Comparably to other European countries, the population progressed remarkably fast from year to year expanding its area geographically but also ecologically by increasing its altitudinal range. The distribution pattern indicates human assisted jump-dispersal travelling on the major traffic routes of central Europe
Evidence for multiple introductions of an invasive wild bee species currently under rapid range expansion in Europe
International audienceBackground: Invasive species are increasingly driving biodiversity decline, and knowledge of colonization dynamics, including both drivers and dispersal modes, are important to prevent future invasions. The bee species Megachile sculpturalis (Hymenoptera: Megachilidae), native to East-Asia, was first recognized in Southeast-France in 2008, and has since spread throughout much of Europe. The spread is very fast, and colonization may result from multiple fronts.Result: To track the history of this invasion, codominant markers were genotyped using Illumina sequencing and the invasion history and degree of connectivity between populations across the European invasion axis were investigated. Distinctive genetic clusters were detected with eastâwest differentiations in Middle-Europe.Conclusion: We hypothesize that the observed cluster formation resulted from multiple, independent introductions of the species to the European continent. This study draws a first picture of an early invasion stage of this wild bee and forms a foundation for further investigations, including studies of the species in their native Asian range and in the invaded range in North America
Effects of inter-raw management intensity on wild bees in Austrian, Spanish, French and Romanian vineyards
International audienc
Effects of inter-raw management intensity on wild bees in Austrian, Spanish, French and Romanian vineyards
International audienc
Management intensity or landscape diversity: What matters most for wild bee diversity in wine-growing areas?
International audienc
Enhancing flowering plant functional richness improves wild bee diversity in vineyard interârows in different floral kingdoms
Abstract Wild bees are threatened by multiple interacting stressors, such as habitat loss, land use change, parasites, and pathogens. However, vineyards with vegetated interârows can offer high floral resources within viticultural landscapes and provide foraging and nesting habitats for wild bees. Here, we assess how vineyard management regimes (organic vs. conventional; interârow vegetation management) and landscape composition determine the interârow plant and wild bee assemblages, as well as how these variables relate to functional traits in 24 Austrian and 10 South African vineyards. Vineyards had either permanent vegetation cover in untilled interârows or temporary vegetation cover in infrequently tilled interârows. Proportion of seminatural habitats (e.g., fallows, grassland, field margins) and woody structures (e.g., woodlots, single trees, tree rows) were used as proxies for landscape composition and mapped within 500âm radius around the study vineyards. Organic vineyard management increased functional richness (FRic) of wild bees and flowering plants, with woody structures marginally increasing species richness and FRic of wild bees. Wild bee and floral traits were differently associated across the countries. In Austria, several bee traits (e.g., lecty, pollen collection type, proboscis length) were associated with flower color and symmetry, while in South African vineyards, only beesâ proboscis length was positively correlated with floral traits characteristic of Asteraceae flowers (e.g., rayâdisk morphology, yellow colors). Solitary bee species in Austria benefitted from infrequent tillage, while ground nesting species preferred interârows with undisturbed soils. Higher proportions of woody structures in surrounding landscapes resulted in less solitary and corbiculate bees in Austria, but more aboveground nesting species in South Africa. In both countries, associations between FRic of wild bees and flowering plants were positive both in organic and in conventional vineyards. We recommend the use of diverse cover crop seed mixtures to enhance plant flowering diversity in interârows, to increase wild bee richness in viticultural landscapes
Management intensity or landscape diversity: What matters most for wild bee diversity in wine-growing areas?.
International audienc
Wild bee diversity and functional traits are affected by interrow management intensity in vineyards across Europe
International audienc