@article{GamezViruesPerovićGossneretal.2015, author = {G{\´a}mez-Viru{\´e}s, Sagrario and Perović, David J. and Gossner, Martin M. and B{\"o}rschig, Carmen and Bl{\"u}thgen, Nico and de Jong, Heike and Simons, Nadja K. and Klein, Alexandra-Maria and Krauss, Jochen and Maier, Gwen and Scherber, Christoph and Steckel, Juliane and Rothenw{\"o}hrer, Christoph and Steffan-Dewenter, Ingolf and Weiner, Christiane N. and Weisser, Wolfgang and Werner, Michael and Tscharntke, Teja and Westphal, Catrin}, title = {Landscape simplification filters species traits and drives biotic homogenization}, series = {Nature Communications}, volume = {6}, journal = {Nature Communications}, number = {8568}, doi = {10.1038/ncomms9568}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-141925}, year = {2015}, abstract = {Biodiversity loss can affect the viability of ecosystems by decreasing the ability of communities to respond to environmental change and disturbances. Agricultural intensification is a major driver of biodiversity loss and has multiple components operating at different spatial scales: from in-field management intensity to landscape-scale simplification. Here we show that landscape-level effects dominate functional community composition and can even buffer the effects of in-field management intensification on functional homogenization, and that animal communities in real-world managed landscapes show a unified response (across orders and guilds) to both landscape-scale simplification and in-field intensification. Adults and larvae with specialized feeding habits, species with shorter activity periods and relatively small body sizes are selected against in simplified landscapes with intense in-field management. Our results demonstrate that the diversity of land cover types at the landscape scale is critical for maintaining communities, which are functionally diverse, even in landscapes where in-field management intensity is high.}, language = {en} } @article{KleijnWinfreeBartomeusetal.2015, author = {Kleijn, David and Winfree, Rachael and Bartomeus, Ignasi and Carvalheiro, Lu{\´i}sa G. and Henry, Mickael and Isaacs, Rufus and Klein, Alexandra-Maria and Kremen, Claire and M'Gonigle, Leithen K. and Rader, Romina and Ricketts, Taylor H. and Williams, Neal M. and Adamson, Nancy Lee and Ascher, John S. and B{\´a}ldi, Andr{\´a}s and Bat{\´a}ry, P{\´e}ter and Benjamin, Faye and Biesmeijer, Jacobus C. and Blitzer, Eleanor J. and Bommarco, Riccardo and Brand, Mariette R. and Bretagnolle, Vincent and Button, Lindsey and Cariveau, Daniel P. and Chifflet, R{\´e}my and Colville, Jonathan F. and Danforth, Bryan N. and Elle, Elizabeth and Garratt, Michael P. D. and Herzog, Felix and Holzschuh, Andrea and Howlett, Brad G. and Jauker, Frank and Jha, Shalene and Knop, Eva and Krewenka, Kristin M. and Le F{\´e}on, Violette and Mandelik, Yael and May, Emily A. and Park, Mia G. and Pisanty, Gideon and Reemer, Menno and Riedinger, Verena and Rollin, Orianne and Rundl{\"o}f, Maj and Sardi{\~n}as, Hillary S. and Scheper, Jeroen and Sciligo, Amber R. and Smith, Henrik G. and Steffan-Dewenter, Ingolf and Thorp, Robbin and Tscharntke, Teja and Verhulst, Jort and Viana, Blandina F. and Vaissi{\`e}re, Bernard E. and Veldtman, Ruan and Ward, Kimiora L. and Westphal, Catrin and Potts, Simon G.}, title = {Delivery of crop pollination services is an insufficient argument for wild pollinator conservation}, series = {Nature Communications}, volume = {6}, journal = {Nature Communications}, number = {7414}, doi = {10.1038/ncomms8414}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-151879}, year = {2015}, abstract = {There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation. However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost- effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery is restricted to a limited subset of all known bee species. Across crops, years and biogeographical regions, crop-visiting wild bee communities are dominated by a small number of common species, and threatened species are rarely observed on crops. Dominant crop pollinators persist under agricultural expansion and many are easily enhanced by simple conservation measures, suggesting that cost- effective management strategies to promote crop pollination should target a different set of species than management strategies to promote threatened bees. Conserving the biological diversity of bees therefore requires more than just ecosystem-service-based arguments.}, language = {en} } @article{VenjakobLeonhardtKlein2020, author = {Venjakob, Christine and Leonhardt, Sara and Klein, Alexandra-Maria}, title = {Inter-individual nectar chemistry changes of field scabious, Knautia arvensis}, series = {Insects}, volume = {11}, journal = {Insects}, number = {2}, issn = {2075-4450}, doi = {10.3390/insects11020075}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200866}, year = {2020}, abstract = {Nectar is crucial to maintain plant-pollinator mutualism. Nectar quality (nutritional composition) can vary strongly between individuals of the same plant species. The factors driving such inter-individual variation have however not been investigated closer. We investigated nectar quality of field scabious, Knautia arvensis in different grassland plant communities varying in species composition and richness to assess whether nectar quality can be affected by the surrounding plant community. We analyzed (with high performance liquid chromatography) the content of carbohydrates, overall amino acids, and essential amino acids. Amino acid and carbohydrate concentrations and proportions varied among plant individuals and with the surrounding plant community but were not related to the surrounding plant species richness. Total and individual carbohydrate concentrations were lowest, while proportions of the essential amino acids, valine, isoleucine, leucine (all phagostimulatory), and lysine were highest in plant species communities of the highest diversity. Our results show that K. arvensis nectar chemistry varies with the composition of the surrounding plant community, which may alter the taste and nutritional value and thus affect the plant's visitor spectrum and visitation rate. However, the strong inter-individual variation in nectar quality requires additional studies (e.g., in semi-field studies) to disentangle different biotic and abiotic factors contributing to inter-individual nectar chemistry in a plant-community context.}, language = {en} } @article{DrescherKleinSchmittetal.2019, author = {Drescher, Nora and Klein, Alexandra-Maria and Schmitt, Thomas and Leonhardt, Sara Diana}, title = {A clue on bee glue: New insight into the sources and factors driving resin intake in honeybees (Apis mellifera)}, series = {PLoS ONE}, volume = {14}, journal = {PLoS ONE}, number = {2}, doi = {10.1371/journal.pone.0210594}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200935}, pages = {e0210594}, year = {2019}, abstract = {Honeybees (Apis mellifera) are threatened by numerous pathogens and parasites. To prevent infections they apply cooperative behavioral defenses, such as allo-grooming and hygiene, or they use antimicrobial plant resin. Resin is a chemically complex and highly variable mixture of many bioactive compounds. Bees collect the sticky material from different plant species and use it for nest construction and protection. Despite its importance for colony health, comparatively little is known about the precise origins and variability in resin spectra collected by honeybees. To identify the botanical resin sources of A. mellifera in Western Europe we chemically compared resin loads of individual foragers and tree resins. We further examined the resin intake of 25 colonies from five different apiaries to assess the effect of location on variation in the spectra of collected resin. Across all colonies and apiaries, seven distinct resin types were categorized according to their color and chemical composition. Matches between bee-collected resin and tree resin indicated that bees used poplar (Populus balsamifera, P. x canadensis), birch (Betula alba), horse chestnut (Aesculus hippocastanum) and coniferous trees (either Picea abies or Pinus sylvestris) as resin sources. Our data reveal that honeybees collect a comparatively broad and variable spectrum of resin sources, thus assuring protection against a variety of antagonists sensitive to different resins and/or compounds. We further unravel distinct preferences for specific resins and resin chemotypes, indicating that honeybees selectively search for bioactive resin compounds.}, language = {en} } @article{DrescherKleinNeumannetal.2017, author = {Drescher, Nora and Klein, Alexandra-Maria and Neumann, Peter and Ya{\~n}ez, Orlando and Leonhardt, Sara D.}, title = {Inside Honeybee Hives: Impact of Natural Propolis on the Ectoparasitic Mite Varroa destructor and Viruses}, series = {Insects}, volume = {8}, journal = {Insects}, number = {1}, doi = {10.3390/insects8010015}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171164}, pages = {15}, year = {2017}, abstract = {Social immunity is a key factor for honeybee health, including behavioral defense strategies such as the collective use of antimicrobial plant resins (propolis). While laboratory data repeatedly show significant propolis effects, field data are scarce, especially at the colony level. Here, we investigated whether propolis, as naturally deposited in the nests, can protect honeybees against ectoparasitic mites Varroa destructor and associated viruses, which are currently considered the most serious biological threat to European honeybee subspecies, Apis mellifera, globally. Propolis intake of 10 field colonies was manipulated by either reducing or adding freshly collected propolis. Mite infestations, titers of deformed wing virus (DWV) and sacbrood virus (SBV), resin intake, as well as colony strength were recorded monthly from July to September 2013. We additionally examined the effect of raw propolis volatiles on mite survival in laboratory assays. Our results showed no significant effects of adding or removing propolis on mite survival and infestation levels. However, in relation to V. destructor, DWV titers increased significantly less in colonies with added propolis than in propolis-removed colonies, whereas SBV titers were similar. Colonies with added propolis were also significantly stronger than propolis-removed colonies. These findings indicate that propolis may interfere with the dynamics of V. destructor-transmitted viruses, thereby further emphasizing the importance of propolis for honeybee health.}, language = {en} }