11769
2014
eng
e82996
1
9
article
1
2015-08-12
--
--
Agricultural Policies Exacerbate Honeybee Pollination Service Supply-Demand Mismatches Across Europe
Declines in insect pollinators across Europe have raised concerns about the supply of pollination services to agriculture. Simultaneously, EU agricultural and biofuel policies have encouraged substantial growth in the cultivated area of insect pollinated crops across the continent. Using data from 41 European countries, this study demonstrates that the recommended number of honeybees required to provide crop pollination across Europe has risen 4.9 times as fast as honeybee stocks between 2005 and 2010. Consequently, honeybee stocks were insufficient to supply >90% of demands in 22 countries studied. These findings raise concerns about the capacity of many countries to cope with major losses of wild pollinators and highlight numerous critical gaps in current understanding of pollination service supplies and demands, pointing to a pressing need for further research into this issue.
PLOS ONE
10.1371/journal.pone.0082996
1932-6203
24421873
urn:nbn:de:bvb:20-opus-117692
PLoS ONE 9(1): e82996. doi:10.1371/journal.pone.0082996
244090
Tom D. Breeze
Bernhard E. Vaissiere
Riccardo Bommarco
Theodora Petanidou
Nicos Seraphides
Lajos Kozak
Jeroen Scheper
Jacobus C. Biesmeijer
David Kleijn
Steen Gyldenkærne
Marco Moretti
Andrea Holzschuh
Ingolf Steffan-Dewenter
Jane C. Stout
Meelis Pärtel
Martin Zobel
Simon G. Potts
eng
uncontrolled
economy services
eng
uncontrolled
fruit set
eng
uncontrolled
sequential introduction
eng
uncontrolled
enhance
eng
uncontrolled
biodiversity
eng
uncontrolled
abundance
eng
uncontrolled
declines
eng
uncontrolled
crops
eng
uncontrolled
colonies
eng
uncontrolled
density
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
OpenAIRE
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/11769/137_Breeze_PLOS_ONE.pdf
11692
2014
eng
e328
2
article
1
2015-07-28
--
--
Contribution of insect pollinators to crop yield and quality varies with agricultural intensification
Background. Up to 75% of crop species benefit at least to some degree from animal pollination for fruit or seed set and yield. However, basic information on the level of pollinator dependence and pollinator contribution to yield is lacking for many crops. Even less is known about how insect pollination affects crop quality. Given that habitat loss and agricultural intensification are known to decrease pollinator richness and abundance, there is a need to assess the consequences for different components of crop production. Methods. We used pollination exclusion on flowers or inflorescences on a whole plant basis to assess the contribution of insect pollination to crop yield and quality in four flowering crops (spring oilseed rape, field bean, strawberry, and buckwheat) located in four regions of Europe. For each crop, we recorded abundance and species richness of flower visiting insects in ten fields located along a gradient from simple to heterogeneous landscapes. Results. Insect pollination enhanced average crop yield between 18 and 71% depending on the crop. Yield quality was also enhanced in most crops. For instance, oilseed rape had higher oil and lower chlorophyll contents when adequately pollinated, the proportion of empty seeds decreased in buckwheat, and strawberries' commercial grade improved; however, we did not find higher nitrogen content in open pollinated field beans. Complex landscapes had a higher overall species richness of wild pollinators across crops, but visitation rates were only higher in complex landscapes for some crops. On the contrary, the overall yield was consistently enhanced by higher visitation rates, but not by higher pollinator richness. Discussion. For the four crops in this study, there is clear benefit delivered by pollinators on yield quantity and/or quality, but it is not maximized under current agricultural intensification. Honeybees, the most abundant pollinator, might partially compensate the loss of wild pollinators in some areas, but our results suggest the need of landscape-scale actions to enhance wild pollinator populations.
PEERJ
10.7717/peerj.328
2167-9843
24749007
urn:nbn:de:bvb:20-opus-116928
PeerJ 2:e328; DOI 10.7717/peerj.328
506675
244090
Ignasi Bartomeus
Simon G. Potts
Ingolf Steffan-Dewenter
Bernard E. Vaissiere
Michal Woyciechowski
Kristin M. Krewenka
Thomas Tscheulin
Stuart P. M. Roberts
Hajnalka Szentgyoergyi
Catrin Westphal
Riccardo Bommarco
eng
uncontrolled
biodiversity
eng
uncontrolled
pollination
eng
uncontrolled
honeybee
eng
uncontrolled
wild bees
eng
uncontrolled
agroecosystems
eng
uncontrolled
native pollinators
eng
uncontrolled
species richness
eng
uncontrolled
bee pollinators
eng
uncontrolled
wild
eng
uncontrolled
ecosystemservices
eng
uncontrolled
fruit-quality
eng
uncontrolled
oilseed rape
eng
uncontrolled
land-use
eng
uncontrolled
honey
eng
uncontrolled
patterns
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
OpenAIRE
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/11692/100_Bartomeus_PeerJ.pdf
11287
2014
eng
article
1
2015-05-08
--
--
Trait-Specific Responses of Wild Bee Communities to Landscape Composition, Configuration and Local Factors
Land-use intensification and loss of semi-natural habitats have induced a severe decline of bee diversity in agricultural landscapes. Semi-natural habitats like calcareous grasslands are among the most important bee habitats in central Europe, but they are threatened by decreasing habitat area and quality, and by homogenization of the surrounding landscape affecting both landscape composition and configuration. In this study we tested the importance of habitat area, quality and connectivity as well as landscape composition and configuration on wild bees in calcareous grasslands. We made detailed trait-specific analyses as bees with different traits might differ in their response to the tested factors. Species richness and abundance of wild bees were surveyed on 23 calcareous grassland patches in Southern Germany with independent gradients in local and landscape factors. Total wild bee richness was positively affected by complex landscape configuration, large habitat area and high habitat quality (i.e. steep slopes). Cuckoo bee richness was positively affected by complex landscape configuration and large habitat area whereas habitat specialists were only affected by the local factors habitat area and habitat quality. Small social generalists were positively influenced by habitat area whereas large social generalists (bumblebees) were positively affected by landscape composition (high percentage of semi-natural habitats). Our results emphasize a strong dependence of habitat specialists on local habitat characteristics, whereas cuckoo bees and bumblebees are more likely affected by the surrounding landscape. We conclude that a combination of large high-quality patches and heterogeneous landscapes maintains high bee species richness and communities with diverse trait composition. Such diverse communities might stabilize pollination services provided to crops and wild plants on local and landscape scales.
10.1371/journal.pone.0104439
urn:nbn:de:bvb:20-opus-112872
PLoS ONE 9(8): e104439. doi:10.1371/journal.pone.0104439
244090
Sebastian Hopfenmueller
Ingolf Steffan-Dewenter
Andrea Holzschuh
eng
uncontrolled
habitats
eng
uncontrolled
bees
eng
uncontrolled
grasslands
eng
uncontrolled
species diversity
eng
uncontrolled
biodiversity
eng
uncontrolled
pollination
eng
uncontrolled
flowers
eng
uncontrolled
foraging
Tiere (Zoologie)
open_access
Theodor-Boveri-Institut für Biowissenschaften
OpenAIRE
Förderzeitraum 2014
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/11287/088_Hopfenmueller_PLoS.pdf
11281
2014
eng
article
1
2015-05-07
--
--
Combined Effects of Extreme Climatic Events and Elevation on Nutritional Quality and Herbivory of Alpine Plants
Climatic extreme events can cause the shift or disruption of plant-insect interactions due to altered plant quality, e.g. leaf carbon to nitrogen ratios, and phenology. However, the response of plant-herbivore interactions to extreme events and climatic gradients has been rarely studied, although climatic extremes will increase in frequency and intensity in the future and insect herbivores represent a highly diverse and functionally important group. We set up a replicated climate change experiment along elevational gradients in the German Alps to study the responses of three plant guilds and their herbivory by insects to extreme events (extreme drought, advanced and delayed snowmelt) versus control plots under different climatic conditions on 15 grassland sites. Our results indicate that elevational shifts in CN (carbon to nitrogen) ratios and herbivory depend on plant guild and season. CN ratios increased with altitude for grasses, but decreased for legumes and other forbs. In contrast to our hypotheses, extreme climatic events did not significantly affect CN ratios and herbivory. Thus, our study indicates that nutritional quality of plants and antagonistic interactions with insect herbivores are robust against seasonal climatic extremes. Across the three functional plant guilds, herbivory increased with nitrogen concentrations. Further, increased CN ratios indicate a reduction in nutritional plant quality with advancing season. Although our results revealed no direct effects of extreme climatic events, the opposing responses of plant guilds along elevation imply that competitive interactions within plant communities might change under future climates, with unknown consequences for plant-herbivore interactions and plant community composition.
10.1371/journal.pone.0093881
urn:nbn:de:bvb:20-opus-112812
PLoS ONE 9(4): e93881. doi:10.1371/journal.pone.0093881
Annette Leingärtner
Bernhard Hoiss
Jochen Krauss
Ingolf Steffan-Dewenter
eng
uncontrolled
Plant-herbivore interactions
eng
uncontrolled
Herbivory
eng
uncontrolled
Leaves
eng
uncontrolled
Grasses
eng
uncontrolled
Legumes
eng
uncontrolled
Insects
eng
uncontrolled
Drought
eng
uncontrolled
Climate Change
Biowissenschaften; Biologie
open_access
Theodor-Boveri-Institut für Biowissenschaften
Förderzeitraum 2014
Universität Würzburg
https://opus.bibliothek.uni-wuerzburg.de/files/11281/081_Leingaertner_PLoS.pdf