@article{GebertSteffan‐DewenterKronbachetal.2022,
  author    = {Gebert, Friederike and Steffan-Dewenter, Ingolf and Kronbach, Patrick and Peters, Marcell K.},
  title     = {The role of diversity, body size and climate in dung removal: A correlative and experimental approach},
  series = {Journal of Animal Ecology},
  volume    = {91},
  journal   = {Journal of Animal Ecology},
  number    = {11},
  doi       = {10.1111/1365-2656.13798},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-293907},
  pages     = {2181 -- 2191},
  year      = {2022},
  abstract  = {The mechanisms by which climatic changes influence ecosystem functions, that is, by a direct climatic control of ecosystem processes or by modifying richness and trait compositions of species communities, remain unresolved. This study is a contribution to this discourse by elucidating the linkages between climate, land use, biodiversity, body size and ecosystem functions. We disentangled direct climatic from biodiversity-mediated effects by using dung removal by dung beetles as a model system and by combining correlative field data and exclosure experiments along an extensive elevational gradient on Mt. Kilimanjaro, Tanzania. Dung removal declined with increasing elevation, being associated with a strong reduction in the richness and body size traits of dung beetle communities. Climate influenced dung removal rates by modifying biodiversity rather than by direct effects. The biodiversity-ecosystem effect was driven by a change in the mean body size of dung beetles. Dung removal rates were strongly reduced when large dung beetles were experimentally excluded. This study underscores that climate influences ecosystem functions mainly by modifying biodiversity and underpins the important role of body size for dung removal.},
  language  = {en}
}
@article{KaluzaWallaceHeardetal.2018,
  author    = {Kaluza, Benjamin F. and Wallace, Helen M. and Heard, Tim A. and Minden, Vanessa and Klein, Alexandra and Leonhardt, Sara D.},
  title     = {Social bees are fitter in more biodiverse environments},
  series = {Scientific Reports},
  volume    = {8},
  journal   = {Scientific Reports},
  number    = {12353},
  doi       = {10.1038/s41598-018-30126-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-177231},
  year      = {2018},
  abstract  = {Bee population declines are often linked to human impacts, especially habitat and biodiversity loss, but empirical evidence is lacking. To clarify the link between biodiversity loss and bee decline, we examined how floral diversity affects (reproductive) fitness and population growth of a social stingless bee. For the first time, we related available resource diversity and abundance to resource (quality and quantity) intake and colony reproduction, over more than two years. Our results reveal plant diversity as key driver of bee fitness. Social bee colonies were fitter and their populations grew faster in more florally diverse environments due to a continuous supply of food resources. Colonies responded to high plant diversity with increased resource intake and colony food stores. Our findings thus point to biodiversity loss as main reason for the observed bee decline.},
  language  = {en}
}
@article{BoetzlSchueleKraussetal.2020,
  author    = {Boetzl, Fabian A. and Schuele, Maren and Krauss, Jochen and Steffan-Dewenter, Ingolf},
  title     = {Pest control potential of adjacent agri-environment schemes varies with crop type and is shaped by landscape context and within-field position},
  series = {Journal of Applied Ecology},
  volume    = {57},
  journal   = {Journal of Applied Ecology},
  number    = {8},
  doi       = {10.1111/1365-2664.13653},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-218265},
  pages     = {1482 -- 1493},
  year      = {2020},
  abstract  = {Increasing natural pest control in agricultural fields is an important aim of ecological intensification. Combined effects of landscape context and local placement of agri-environmental schemes (AES) on natural pest control and within-field distance functions of natural pest control agents have rarely been addressed but might affect the distribution of biocontrol providers. Importantly, it is currently unknown whether ecosystem services provided by adjacent AES are consistent for different crop types during crop rotation. In this study, we assessed whether crop rotation from oilseed rape to cereals altered within-field distance functions of ground-dwelling predators from adjacent agri-environmental fields along a gradient in landscape context. Additionally, we recorded crop pests, predation rates, parasitoids as well as crop yields on a total of 30 study sites. Distance functions varied between trophic levels: Carabid richness decreased while densities of carabid beetles, staphylinid beetles as well as crop yields increased towards the field centres. Distance functions of parasitoids and pests were modulated by the amount of semi-natural habitat in the surrounding landscape, while the effects of adjacent AES were limited. Distance decay functions found for ground-dwelling predators in oilseed rape in the previous year were not always present in cereals. Increasing distance to the field edge also increased effects of crop rotation on carabid beetle assemblages, indicating a source habitat function of field edges. Synthesis and applications. Distance functions of natural pest control are not universal and the effects of agri-environmental schemes (AES) in different adjacent crops during crop rotation vary and depend on ecological contrasts. A network of semi-natural habitats and spatially optimized AES habitats can benefit pest control in agricultural landscapes, but constraints as a result of crop type need to be addressed by annually targeted, spatially shifting agri-environment schemes for different crops.},
  language  = {en}
}
@article{HolzschuhDaineseGonzalezVaroetal.2016,
  author    = {Holzschuh, Andrea and Dainese, Matteo and Gonzalez-Varo, Juan P. and Mudri-Stojnic, Sonja and Riedinger, Verena and Rundl{\"o}f, Maj and Scheper, Jeroen and Wickens, Jennifer B. and Wickens, Victoria J. and Bommarco, Riccardo and Kleijn, David and Potts, Simon G. and Roberts, Stuart P. M. and Smith, Henrik G. and Vil{\`a}, Montserrat and Vujic, Ante and Steffan-Dewenter, Ingolf},
  title     = {Mass-flowering crops dilute pollinator abundance in agricultural landscapes across Europe},
  series = {Ecology Letters},
  volume    = {19},
  journal   = {Ecology Letters},
  number    = {10},
  doi       = {10.1111/ele.12657},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-187356},
  pages     = {1228-1236},
  year      = {2016},
  abstract  = {Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were negatively related to the cover of MFCs in the landscape. In SNHs, densities of bumblebees declined with increasing cover of MFCs but densities of honeybees increased. The densities of all pollinators were generally unrelated to the cover of SNHs in the landscape. Although MFC fields apparently attracted pollinators from SNHs, in landscapes with large areas of MFCs they became diluted. The resulting lower densities might negatively affect yields of pollinator- dependent crops and the reproductive success of wild plants. An expansion of MFCs needs to be accompanied by pollinator-supporting practices in agricultural landscapes.},
  language  = {en}
}
@article{KrimmerMartinHolzschuhetal.2022,
  author    = {Krimmer, Elena and Martin, Emily A. and Holzschuh, Andrea and Krauss, Jochen and Steffan-Dewenter, Ingolf},
  title     = {Flower fields and pesticide use interactively shape pollen beetle infestation and parasitism in oilseed rape fields},
  series = {Journal of Applied Ecology},
  volume    = {59},
  journal   = {Journal of Applied Ecology},
  number    = {1},
  doi       = {10.1111/1365-2664.14051},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258037},
  pages     = {263-273},
  year      = {2022},
  abstract  = {Pollen beetles (Brassicogethes spp.) are the main pests of oilseed rape (OSR, Brassica napus) in Europe and responsible for massive yield losses. Upcoming pesticide resistances highlight the need for other means of crop protection, such as natural pest control. Sown flower fields aim to counteract the decrease of insect biodiversity in agricultural landscapes by providing resources to ecosystem service providers. However, the optimal age and size of flower fields to increase natural pest control is still unclear. We conducted experiments on 31 OSR fields located along a gradient of landscape-scale semi-natural habitat (SNH). OSR fields were located adjacent to flower fields which differed in age, continuity and size, or adjacent to crop fields or calcareous grasslands. Pesticide-free areas were established to examine interactive effects of pesticide use and flower field characteristics. The abundance of pollen beetle adults and larvae, parasitism and superparasitism rates in OSR were recorded at increasing distances to the adjacent sites. Flower fields and calcareous grasslands increased pollen beetle parasitism when compared to OSR fields neighbouring crop fields. The threshold for effective natural pest control of 35\% could be reached in the pesticide-free areas of OSR fields adjacent to calcareous grasslands and flower fields maintained continuously for at least 6 years. In pesticide-sprayed areas, pollen beetle parasitism and superparasitism declined with increasing distance to the adjacent field. Furthermore, flower fields larger than 1.5 ha were able to improve pollen beetle parasitism more than smaller fields. Synthesis and applications. To promote natural pest control in oilseed rape (OSR), large flower fields should be maintained for several years, to create stable habitats for natural enemies. The continuous maintenance of flower fields should be preferred, as ploughing and resowing after 5-6 years decreased the positive effects of the flower fields on natural pest control in adjacent OSR fields. However, pesticide use can abrogate positive effects of flower fields on pollen beetle parasitism. This study highlights that sown flower fields have the potential to increase natural pest control in OSR, but this potential is depending on its age, continuity and size and can be hindered by pesticide use.},
  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{DaineseSchneiderKraussetal.2017,
  author    = {Dainese, Matteo and Schneider, Gudrun and Krauss, Jochen and Steffan-Dewenter, Ingolf},
  title     = {Complementarity among natural enemies enhances pest suppression},
  series = {Scientific Reports},
  volume    = {7},
  journal   = {Scientific Reports},
  doi       = {10.1038/s41598-017-08316-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158621},
  pages     = {8172},
  year      = {2017},
  abstract  = {Natural enemies have been shown to be effective agents for controlling insect pests in crops. However, it remains unclear how different natural enemy guilds contribute to the regulation of pests and how this might be modulated by landscape context. In a field exclusion experiment in oilseed rape (OSR), we found that parasitoids and ground-dwelling predators acted in a complementary way to suppress pollen beetles, suggesting that pest control by multiple enemies attacking a pest during different periods of its occurrence in the field improves biological control efficacy. The density of pollen beetle significantly decreased with an increased proportion of non-crop habitats in the landscape. Parasitism had a strong effect on pollen beetle numbers in landscapes with a low or intermediate proportion of non-crop habitats, but not in complex landscapes. Our results underline the importance of different natural enemy guilds to pest regulation in crops, and demonstrate how biological control can be strengthened by complementarity among natural enemies. The optimization of natural pest control by adoption of specific management practices at local and landscape scales, such as establishing non-crop areas, low-impact tillage, and temporal crop rotation, could significantly reduce dependence on pesticides and foster yield stability through ecological intensification in agriculture.},
  language  = {en}
}
@article{KlattHolzschuhWestphaletal.2014,
  author    = {Klatt, Bj{\"o}rn K. and Holzschuh, Andrea and Westphal, Catrin and Clough, Yann and Smit, Inga and Pawelzik, Elke and Tscharntke, Teja},
  title     = {Bee pollination improves crop quality, shelf life and commercial value},
  series = {Proceedings of the Royal Society B: Biological Sciences},
  volume    = {281},
  journal   = {Proceedings of the Royal Society B: Biological Sciences},
  number    = {1775},
  doi       = {10.1098/rspb.2013.2440},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120797},
  year      = {2014},
  abstract  = {Pollination improves the yield of most crop species and contributes to one-third of global crop production, but comprehensive benefits including crop quality are still unknown. Hence, pollination is underestimated by international policies, which is particularly alarming in times of agricultural intensification and diminishing pollination services. In this study, exclusion experiments with strawberries showed bee pollination to improve fruit quality, quantity and market value compared with wind and self-pollination. Bee-pollinated fruits were heavier, had less malformations and reached higher commercial grades. They had increased redness and reduced sugar-acid-ratios and were firmer, thus improving the commercially important shelf life. Longer shelf life reduced fruit loss by at least 11\%. This is accounting for 0.32 billion US\$ of the 1.44 billion US\$ provided by bee pollination to the total value of 2.90 billion US\$ made with strawberry selling in the European Union 2009. The fruit quality and yield effects are driven by the pollination-mediated production of hormonal growth regulators, which occur in several pollination-dependent crops. Thus, our comprehensive findings should be transferable to a wide range of crops and demonstrate bee pollination to be a hitherto underestimated but vital and economically important determinant of fruit quality.},
  language  = {en}
}