| 1. |
- Andersson, Georg, et al.
(författare)
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Glöm inte vildbina
- 2013
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Ingår i: Skånes Fria Tidning.
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 2. |
- Andersson, Georg, et al.
(författare)
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Massdöd av bin hotar jordbruket
- 2013
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Ingår i: Göteborgsposten. - 1103-9345.
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 3. |
- Ekroos, Johan, et al.
(författare)
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Effects of landscape composition and configuration on pollination in a native herb : a field experiment
- 2015
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Ingår i: Oecologia. - : Springer Science and Business Media LLC. - 0029-8549 .- 1432-1939. ; 179:2, s. 509-518
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Tidskriftsartikel (refereegranskat)abstract
- Bumble bee abundance in agricultural landscapes is known to decrease with increasing distance from seminatural grasslands, but whether the pollination of bumble-bee-pollinated wild plants shows a similar pattern is less well known. In addition, the relative effects of landscape composition (landscape heterogeneity) and landscape configuration (distance from seminatural grassland) on wild plant pollination, and the interaction between these landscape effects, have not been studied using landscape-level replication. We performed a field experiment to disentangle these landscape effects on the pollination of a native herb, the sticky catchfly (Lychnis viscaria), while accounting for the proportion of oilseed rape across landscapes and the local abundance of bee forage flowers. We measured pollen limitation (the degree to which seed set is pollen-limited), seed set, and seed set stability using potted plants placed in landscapes that differed in heterogeneity (composition) and distance from seminatural grassland (configuration). Pollen limitation and seed set in individual plants did not respond to landscape composition, landscape configuration, or proportion of oilseed rape. Instead, seed set increased with increasing local bee forage flower cover. However, we found within-plant variability in pollen limitation and seed set to increase with increasing distance from seminatural pasture. Our results suggest that average within-plant levels of pollen limitation and seed set respond less swiftly than the within-plant variability in pollen limitation and seed set to changes in landscape configuration. Although landscape effects on pollination were less important than predicted, we conclude that landscape configuration and local habitat characteristics play larger roles than landscape composition in the pollination of L. viscaria.
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| 4. |
- Ekroos, Johan, et al.
(författare)
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Sparing land for biodiversity at multiple spatial scales
- 2016
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Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media SA. - 2296-701X. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- A common approach to the conservation of farmland biodiversity and the promotion of multifunctional landscapes, particularly in landscapes containing only small remnants of non-crop habitats, has been to maintain landscape heterogeneity and reduce land-use intensity. In contrast, it has recently been shown that devoting specific areas of non-crop habitats to conservation, segregated from high-yielding farmland (“land sparing”), can more effectively conserve biodiversity than promoting low-yielding, less intensively managed farmland occupying larger areas (“land sharing”). In the present paper we suggest that the debate over the relative merits of land sparing or land sharing is partly blurred by the differing spatial scales at which it is suggested that land sparing should be applied. We argue that there is no single correct spatial scale for segregating biodiversity protection and commodity production in multifunctional landscapes. Instead we propose an alternative conceptual construct, which we call “multiple-scale land sparing,” targeting biodiversity and ecosystem services in transformed landscapes. We discuss how multiple-scale land sparing may overcome the apparent dichotomy between land sharing and land sparing and help to find acceptable compromises that conserve biodiversity and landscape multifunctionality.
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| 5. |
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| 6. |
- Herbertsson, Lina, et al.
(författare)
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Assessing the risk of stigma clogging in strawberry flowers due to pollinator sharing with oilseed rape
- 2017
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Ingår i: Journal of Pollination Ecology. - 1920-7603. ; 21:2, s. 71-77
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Tidskriftsartikel (refereegranskat)abstract
- Strawberry and oilseed rape are economically important and co-flowering insect-pollinated crops that may affect each other via shared pollinators. One potential negative effect of pollinator sharing is stigma clogging, i.e. that pollen from one plant species covers the stigma and prevents pollination in the other. We tested if application of oilseed rape pollen on strawberry receptacles reduces pollination with subsequent effects on strawberry weight, number of malformations and ripening time. We simulated real pollination situations by using dead bees mounted on toothpicks to mimic flower-visitation of foraging bees. Six strawberry flowers, usually on different plant individuals, were hand-pollinated sequentially per simulated foraging bout. In half of these foraging bouts, we started with an oilseed rape flower, and in those foraging bouts the proportion oilseed rape pollen was expected to decline with increasing number of visited strawberry flowers. Oilseed rape pollen had no effect on any of the tested variables. Increasing number of previously visited strawberry flowers in the simulated foraging bout enhanced the number of developed achenes, but this was marginally non-significant when accounting for the total number of achenes. Strawberry weight increased and ripening time decreased with increasing number of pollinated achenes, whereas none of the tested factors had any effect on the number of malformations. Our results have implications for strawberry farmers, because shortened ripening time could reduce the risk of yield loss from pests, diseases and unfavourable weather conditions. In addition, we show that oilseed rape pollen is unlikely to disturb pollination success of strawberry flowers.
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| 7. |
- Herbertsson, Lina, et al.
(författare)
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Bees increase seed set of wild plants while the proportion of arable land has a variable effect on pollination in European agricultural landscapes
- 2021
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Ingår i: Plant Ecology and Evolution. - : Societe Royale de Botanique de Belgique. - 2032-3913 .- 2032-3921. ; 154:3, s. 341-350
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Tidskriftsartikel (refereegranskat)abstract
- Background and aims: Agricultural intensification and loss of farmland heterogeneity have contributed to population declines of wild bees and other pollinators, which may have caused subsequent declines in insect-pollinated wild plants.Material and methods: Using data from 37 studies on 22 pollinator-dependent wild plant species across Europe, we investigated whether flower visitation and seed set of insect-pollinated plants decline with an increasing proportion of arable land within 1 km.Key results: Seed set increased with increasing flower visitation by bees, most of which were wild bees, but not with increasing flower visitation by other insects. Increasing proportion of arable land had a strongly variable effect on seed set and flower visitation by bees across studies.Conclusion:Factors such as landscape configuration, local habitat quality, and temporally changing resource availability (e.g. due to mass-flowering crops or honey bee hives) could have modified the effect of arable land on pollination. While our results highlight that the persistence of wild bees is crucial to maintain plant diversity, we also show that pollen limitation due to declining bee populations in homogenized agricultural landscapes is not a universal driver causing parallel losses of bees and insect-pollinated plants.
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| 8. |
- Herbertsson, Lina, et al.
(författare)
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Competition between managed honeybees and wild bumblebees depends on landscape context
- 2016
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791 .- 1618-0089. ; 17:7, s. 609-616
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Tidskriftsartikel (refereegranskat)abstract
- Honeybees might outcompete wild bees by depleting common resources, possibly more so in simplified landscapes where flower-rich habitats have been lost. We tested this by experimentally adding honeybee hives to nine sites while ensuring that ten additional sites were free from hives. The landscape surrounding each geographically separated site either held low (homogeneous landscape) or high (heterogeneous landscape) proportions of semi-natural grassland. Adding honeybees suppressed bumblebee densities in field borders and road verges in homogeneous landscapes whereas no such effect was detected in heterogeneous landscapes. The proportional abundance of bumblebee species with small foraging ranges was lower at honeybee sites than at control sites in heterogeneous landscapes, whereas bumblebee communities in homogeneous landscapes were dominated by a single species with long foraging range irrespective of if honeybees were added or not. We conclude that honeybees can impact bumblebee densities, but that landscape heterogeneity modified this effect.
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| 9. |
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| 10. |
- Herbertsson, Lina, et al.
(författare)
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Long-term data shows increasing dominance of Bombus terrestris with climate warming
- 2021
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791. ; 53, s. 116-123
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Tidskriftsartikel (refereegranskat)abstract
- While many bumblebee species decline due to climate and land-use changes, others cope well with contemporary conditions. One example is Bombus terrestris, which is common in intensively managed agricultural landscapes. During the 20th century its subgenus, which includes the B. lucorum complex (B. lucorum, B. cryptarum and B. magnus) came to dominate Scandinavian bumblebee communities, but the specific contribution of B. terrestris remains to be understood. Using historical data on males, we assessed how the relative abundances of B. terrestris and the B. lucorum complex changed over the past 150 years in southernmost Sweden. We tested if these changes differed between simplified and mixed landscapes and whether the relative abundance of B. terrestris was related to annual mean temperatures. Because floral availability has advanced as a response to climate change, we also tested if the activity period of males (estimated as catching date) has advanced and whether the advancement differs between taxa. The relative abundance of B. terrestris increased similarly in both landscapes, from 21% to 79% over the period, and this was largely explained by increasing temperature. Male activity period has advanced similarly in the two taxa, with 41 days between 1900 and 2015. Although the dominance of B. terrestris correlates clearly with annual mean temperature, it remains to disentangle why. It also remains to understand whether the success of B. terrestris occurs at the expense of other species or simply reflects that this species copes better with contemporary conditions.
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| 11. |
- Herbertsson, Lina
(författare)
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Pollinators and Insect Pollination in Changing Agricultural Landscapes
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Agricultural intensification and associated loss of semi-natural grasslands, has resulted in reduced landscape heterogeneity. A concomitant loss of forage and nest sites for pollinating insects has driven declines across several pollinator taxa. Because 75% of the cultivated crops and more than 85% of the flowering plant species are insectpollinated, concerns have been raised that the pollinator declines will have consequences for human food supply and plant conservation. Several instances (e.g. the UN and EU) have reacted and initiatives are taken at different levels to increase floral resources for pollinators and also to benefit beekeeping. In order to restore populations of wild pollinators and protect their valuable functions, it is important to understand the complexity of plant-pollinator interactions. In this thesis, I assessed how some factors related to agriculture affect pollinators and pollination, mainly focusing on wild plant andpollinator species. One study was performed by compiling data from several native plant species across Europe. For three additional studies, I collected field data. I found that a lack of landscape heterogeneity can reduce the number of flowervisiting pollinators in European semi-natural habitats (including semi-natural grasslands and semi-open bushlands) and result in competition for floral resources between managed honey bees and wild bumble bees. There was no general effect of landscape heterogeneity on the reproductive success of insect-pollinated plants in European agricultural landscapes. Instead, the field studies suggested that landscape heterogeneity modifies the impact of other factors. For example, the cultivation of oilseed rape benefitted the reproductive success of one later-flowering study species, but not another, and only in landscapes with low heterogeneity. Also, sown flower strips, which are used to supply pollinators with floral resources, benefitted the reproductive success of adjacent plants in landscapes with low heterogeneity, but had a negative impact on the reproductive success of adjacent plants in more heterogeneous landscapes. As many previous studies, this thesis highlights the importance of preserving landscape heterogeneity and semi-natural grasslands in order to protect viable pollinators populations. Although I found no general impact of landscape heterogeneity on plant reproductive success, the persistence of insect-pollinated plants will largely depend on pollinator availability, and thereby on maintained semi-natural grasslands. The maintenance of semi-natural grasslands and landscape heterogeneity in general are important for wild pollinators and can reduce the negative consequences on their populations from competition with managed honey bees. The restoration and maintenance of these habitats may be particularly important in heterogeneous landscapes, where they are particularly species rich and the opportunity cost for the farmers is lower than in homogeneous landscapes. In homogeneous landscapes, where semi-natural grasslands are scarce and more difficult to maintain because of a lack of animal husbandry and a high opportunity cost, sown flower strips can be used to benefit common ecosystem service providing organisms and to some extent the pollination of wild plants.
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| 12. |
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| 13. |
- Herbertsson, Lina, et al.
(författare)
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Seed-coating of rapeseed (Brassica napus) with the neonicotinoid clothianidin affects behaviour of red mason bees (Osmia bicornis) and pollination of strawberry flowers (Fragaria × ananassa)
- 2022
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 17:9 September
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Tidskriftsartikel (refereegranskat)abstract
- Neonicotinoid insecticides applied to flowering crops can have negative impacts on bees, with implications for crop pollination. To assess if exposure to the neonicotinoid clothianidin via a treated crop (rapeseed) affected bee behaviour, pollination performance (to strawberry), and bee reproduction, we provided each of 12 outdoor cages with rapeseed (autumn-sown plants complemented with a few spring-sown plants to extend the flowering period) grown from either clothianidin-treated or untreated (control) seeds, together with strawberry plants and a small population of red mason bees (Osmia bicornis). We expected clothianidin to reduce bee foraging activity, resulting in impaired strawberry pollination and bee reproduction. During the early stage of the experiment, we observed no difference between treatments in the length of entire foraging trips, or the combined number of rapeseed and strawberry flowers that the bees visited during these trips. During the later stage of the experiment, we instead determined the time a female took to visit 10 rapeseed flowers, as a proxy for foraging performance. We found that they were 10% slower in clothianidin cages. Strawberries weighed less in clothianidin cages, suggesting reduced pollination performance, but we were unable to relate this to reduced foraging activity, because the strawberry flowers received equally many visits in the two treatments. Clothianidin-exposed females sealed their nests less often, but offspring number, sex ratio and weight were similar between treatments. Observed effects on bee behaviour appeared by the end of the experiment, possibly because of accumulated effects of exposure, reduced bee longevity, or higher sensitivity of the protocols we used during the later phase of the experiment. Although the lack of a mechanistic explanation calls for interpreting the results with cautiousness, the lower strawberry weight in clothianidin cages highlights the importance of understanding complex effects of plant protection products, which could have wider consequences than those on directly exposed organisms.
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| 14. |
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| 15. |
- Herbertsson, Lina, et al.
(författare)
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The impact of sown flower strips on plant reproductive success in Southern Sweden varies with landscape context
- 2018
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809. ; 259, s. 127-134
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Tidskriftsartikel (refereegranskat)abstract
- In agricultural landscapes, sown flower strips can benefit pollinators and pollination of nearby plants, but their impact on pollination in the wider landscape is poorly studied. We evaluated effects on reproductive success of field bean (Vicia faba) and woodland strawberry (Fragaria vesca) using data from two study systems, both including study sites (1 km radius) with (flower strip sites) or without flower strips (control sites). To assess whether flower strips enhance pollination in the wider landscape, we compared the reproductive success between plants growing in field borders (> 160 m to nearest flower strip) at flower strips sites and control sites. We also tested if flower strips reallocate pollination functions in the landscape. We did this by comparing the reproductive success of plants at flower strip sites, growing adjacent to the flower strips with plants growing in a more distant field border at the same site (> 160 m). Finally, we tested if these potential effects depended on the heterogeneity of the landscape. In field borders without an adjacent flower strip, plant reproductive success was unaffected by the presence of a flower strip at the site, and increased with increasing landscape heterogeneity independently of site type (flower strip vs. control). In contrast, adjacent to the flower strips, reproductive success declined with increasing landscape heterogeneity, resulting in a positive net effect of adjacent flower strips in homogeneous landscapes and a negative effect in heterogeneous landscapes. Our results show that while decreasing landscape heterogeneity may impair pollination in homogeneous landscapes, this can be locally mitigated by sowing flower strips. However, in heterogeneous landscapes, flower strips may instead reduce pollination of adjacent plants.
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| 16. |
- Herbertsson, Lina, et al.
(författare)
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The relation between oilseed rape and pollination of later flowering plants varies across plant species and landscape contexts
- 2017
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791. ; 24, s. 77-85
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Tidskriftsartikel (refereegranskat)abstract
- Increasing cultivation of oilseed rape may have consequences for pollinators and wild plant pollination. By providing pollinating insects with pollen and nectar, oilseed rape benefits short-tongued, generalist insect species. Long-tongued bumble bee species, specialized to other flower types, may instead be negatively affected by increased competition from the generalists (e.g. due to nectar-robbing of long-tubed flowers) after oilseed rape flowering has ceased. We expected that the increased abundance of short-tongued pollinators and reduced abundance of long-tongued bumble bees in landscapes with a high proportion of oilseed rape would impact the pollination of later flowering wild plant species. In addition, we expected contrasting effects on plants pollinated by short-tongued pollinators and those pollinated by long-tongued bumble bees. We predicted that semi-natural grasslands, which provide insects with alternative floral resources, would reduce both negative and positive effects on pollination by mitigating competition between pollinators.In 16 semi-natural grasslands, surrounded by agricultural landscapes, with a variation in both the proportion of oilseed rape and the proportion of semi-natural grassland within 1. km, we studied reproductive output in two species of potted plants with different pollination strategies: the woodland strawberry (Fragaria vesca) and red clover (Trifolium pratense). The first species is mainly pollinated by short-tongued pollinators, e.g. hoverflies and solitary bees, and the latter by long-tongued bumble bees. Both species flowered after oilseed rape.Strawberry weight was higher in landscapes with a high proportion of oilseed rape, but only in landscapes with a low proportion of semi-natural grassland. The proportion of developed achenes was also positively related to the proportion of oilseed rape, but only during the latest flowering period. In contrast, red clover seed set was unrelated to the proportion of oilseed rape. Whereas the discrepancy between the two strawberry measurements calls for further research, this study suggests that oilseed rape can affect later flowering plants and that the impact differs among species.
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| 17. |
- Horstmann, Svenja, et al.
(författare)
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Traffic intensity and vegetation management affect flower‐visiting insects and their response to resources in road verges
- 2024
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Ingår i: Journal of Applied Ecology. - Chichester : Wiley-Blackwell. - 0021-8901 .- 1365-2664.
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Tidskriftsartikel (refereegranskat)abstract
- Road verges can support high densities of flowers and could therefore provide new opportunities for the conservation of flower-visiting insects. One way of optimizing road verges for vascular plant diversity is to adjust mowing regimes, but to date it is unclear how this affects flower-visiting insects. Furthermore, for mobile organisms like wild bees and butterflies, there is a risk that the benefit of increased habitat quality in road verges is limited by the proximity to traffic, but this is poorly studied. In a crossed study design, we separated mowing time and frequency (early summer and autumn, or only late summer) from road verge habitat classification (valuable for biodiversity according to transport authority, or regular). We did so along a gradient of traffic intensity, to investigate if a mowing regime designed to enhance plant diversity can also benefit wild bees and butterflies, and if traffic limits the conservation potential of road verges. Road verges that were mown only in late summer had higher flower densities, and there was a positive relationship between flower density and wild bee abundance and species richness. Butterfly abundance and species richness only benefitted from a late summer mowing in valuable but not in regular road verges. Traffic intensity had a substantial negative impact on abundance and species richness of wild bees and butterflies. Higher traffic intensities limited the positive relationship between plant and butterfly species richness that we observed at lower traffic intensities. Increasing width of the road verges buffered negative effects of the traffic on wild bee as well as butterfly abundances, and on wild bee species richness. Synthesis and applications. Road verges can play a valuable role for the conservation of wild bees and butterflies, but there is a need to consider both traffic intensity and resource availability when implementing management strategies. To support wild bee and butterfly diversity, we recommend actions to enhance plant species richness and flower resource availability, and to focus these conservation efforts on roads with low traffic intensity, or on wide road verges. © 2024 The Author(s). Journal of Applied Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.
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| 18. |
- Kardum Hjort, Cecilia, et al.
(författare)
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Genomic divergence and a lack of recent introgression between commercial and wild bumblebees (Bombus terrestris)
- 2022
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Ingår i: Evolutionary Applications. - : Wiley. - 1752-4571. ; 15:3, s. 365-382
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Tidskriftsartikel (refereegranskat)abstract
- The global movement of bees for agricultural pollination services can affect local pollinator populations via hybridization. When commercial bumblebees are of the same species but of different geographic origin, intraspecific hybridization may result in beneficial integration of new genetic variation, or alternatively may disrupt locally adapted gene complexes. However, neither the existence nor the extent of genomic introgression and evolutionary divergence between wild and commercial bumblebees is fully understood. We obtained whole-genome sequencing data from wild and commercial Bombus terrestris collected from sites in Southern Sweden with and without long-term use of commercially imported B. terrestris. We search for evidence of introgression, dispersal and genome-wide differentiation in a comparative genomic analysis of wild and commercial bumblebees. Commercial B. terrestris were found in natural environments near sites where commercial bumblebees were used, as well as drifting wild B. terrestris in commercial bumblebee colonies. However, we found no evidence for widespread, recent genomic introgression of commercial B. terrestris into local wild conspecific populations. We found that wild B. terrestris had significantly higher nucleotide diversity (Nei's pi, π), while the number of segregating sites (Watterson's theta, θw) was higher in commercial B. terrestris. A highly divergent region on chromosome 11 was identified in commercial B. terrestris and found to be enriched with structural variants. The genes present in this region are involved in flight muscle contraction and structure and pathogen immune response, providing evidence for differing evolutionary processes operating in wild and commercial B. terrestris. We did not find evidence for recent introgression, suggesting that co-occurring commercial B. terrestris have not disrupted evolutionary processes in wild B. terrestris populations.
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| 19. |
- Klatt, Björn K., 1980-, et al.
(författare)
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Seed treatment with clothianidin induces changes in plant metabolism and alters pollinator foraging preferences
- 2023
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Ingår i: Ecotoxicology. - New York, NY : Springer. - 0963-9292 .- 1573-3017. ; 32:10, s. 1247-1256
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Tidskriftsartikel (refereegranskat)abstract
- Neonicotinoids, systemic insecticides that are distributed into all plant tissues and protect against pests, have become a common part of crop production, but can unintentionally also affect non-target organisms, including pollinators. Such effects can be direct effects from insecticide exposure, but neonicotinoids can affect plant physiology, and effects could therefore also be indirectly mediated by changes in plant phenology, attractiveness and nutritional value. Under controlled greenhouse conditions, we tested if seed treatment with the neonicotinoid clothianidin affected oilseed rape’s production of flower resources for bees and the content of the secondary plant products glucosinolates that provide defense against herbivores. Additionally, we tested if seed treatment affected the attractiveness of oilseed rape to flower visiting bumblebees, using outdoor mesocosms. Flowers and leaves of clothianidin-treated plants had different profiles of glucosinolates compared with untreated plants. Bumblebees in mesocosms foraged slightly more on untreated plants. Neither flower timing, flower size nor the production of pollen and nectar differed between treatments, and therefore cannot explain any preference for untreated oilseed rape. We instead propose that this small but significant preference for untreated plants was related to the altered glucosinolate profile caused by clothianidin. Thereby, this study contributes to the understanding of the complex relationships between neonicotinoid-treated crops and pollinator foraging choices, by suggesting a potential mechanistic link by which insecticide treatment can affect insect behavior.
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| 20. |
- Lindström, Sandra A M, et al.
(författare)
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Experimental evidence that honeybees depress wild insect densities in a flowering crop
- 2016
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Ingår i: Proceedings of the Royal Society B: Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 283:1843
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Tidskriftsartikel (refereegranskat)abstract
- While addition of managed honeybees (Apis mellifera) improves pollination of many entomophilous crops, it is unknown if it simultaneously suppresses the densities of wild insects through competition. To investigate this, we added 624 honeybee hives to 23 fields of oilseed rape (Brassica napus L.) over 2 years and made sure that the areas around 21 other fields were free from honeybee hives. We demonstrate that honeybee addition depresses the densities of wild insects (bumblebees, solitary bees, hoverflies, marchflies, other flies, and other flying and flower-visiting insects) even in a massive flower resource such as oilseed rape. The effect was independent of the complexity of the surrounding landscape, but increased with the size of the crop field, which suggests that the effect was caused by spatial displacement of wild insects. Our results have potential implications both for the pollination of crops (if displacement of wild pollinators offsets benefits achieved by adding honeybees) and for conservation of wild insects (if displacement results in negative fitness consequences).
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| 21. |
- Lindström, Sandra A.M., et al.
(författare)
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Simple and farmer-friendly bumblebee conservation : Straw bales as nest sites in agricultural landscapes
- 2022
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791. ; 63, s. 196-205
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Tidskriftsartikel (refereegranskat)abstract
- Many bumblebee species are declining due to a loss of semi-natural habitats in agricultural landscapes resulting in diminished forage and nest sites. Anecdotal experience indicates that bumblebees nest in straw bales, but scientific evidence is lacking. We spent 250 h screening for bumblebee nests in 1255 straw bales and ten straw stacks belonging to 58 farms in two intensively farmed Swedish regions and recorded nests, nest traffic, and straw characteristics. We supplemented the straw screening with screening of control areas, without straw, that were selected in similar environments as the areas with straw. We observed 45 bumblebee nests (including potential nests where a single bumblebee flew in or out of the straw) of eight species/species groups, including one red-listed, in or directly adjacent to the straw at 26 of the farms. Nests were mainly found in partly decayed straw and bales placed together. We found no nests in control areas. Based on our results, we suggest that straw can be used as an easy, cheap and efficient intervention to increase the availability of bumblebee nest sites in agricultural landscapes. Considering the costs and benefits of the alternatives, we conclude that straw addition has advantages over commercial bumblebee colonies for crop pollination purposes and over artificial nest boxes for conservation purposes.
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| 22. |
- Lindström, Sandra, et al.
(författare)
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Large-scale pollination experiment demonstrates the importance of insect pollination in winter oilseed rape
- 2016
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Ingår i: Oecologia. - : Springer Science and Business Media LLC. - 0029-8549 .- 1432-1939. ; 180, s. 759-769
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Tidskriftsartikel (refereegranskat)abstract
- Insect pollination, despite its potential to contribute substantially to crop production, is not an integrated part of agronomic planning. A major reason for this are knowledge gaps in the contribution of pollinators to yield, which partly result from difficulties in determining area-based estimates of yield effects from insect pollination under field conditions. We have experimentally manipulated honey bee Apis mellifera densities at 43 oilseed rape Brassica napus fields over 2 years in Scandinavia. Honey bee hives were placed in 22 fields; an additional 21 fields without large apiaries in the surrounding landscape were selected as controls. Depending on the pollination system in the parental generation, the B. napus cultivars in the crop fields are classified as either open-pollinated or first-generation hybrids, with both types being open-pollinated in the generation of plants cultivated in the fields. Three cultivars of each type were grown. We measured the activity of flower-visiting insects during flowering and estimated yields by harvesting with small combine harvesters. The addition of honey bee hives to the fields dramatically increased abundance of flower-visiting honey bees in those fields. Honey bees affected yield, but the effect depended on cultivar type (p = 0.04). Post-hoc analysis revealed that open-pollinated cultivars, but not hybrid cultivars, had 11% higher yields in fields with added honey bees than those grown in the control fields (p = 0.07). To our knowledge, this is the first whole-field study in replicated landscapes to assess the benefit of insect pollination in oilseed rape. Our results demonstrate that honey bees have the potential to increase oilseed rape yields, thereby emphasizing the importance of pollinator management for optimal cultivation of oilseed rape.
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| 23. |
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| 24. |
- Persson, Anna S., et al.
(författare)
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Hjälp bina på rätt sätt : satsa på blommor istället för bikupor
- 2019
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Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- På senare tid har allt fler aktörer engagerat sig för att ”hjälpa bina” och motverka bidöd. Men när köpcentrum, snabbmatskedjor och fastighetsbolag satsar på bikupor för honungsbin i stället för att hjälpa vilda bin riskerar man att göra mer skada än nytta, skriver fyra Lundaforskare, som uppmanar företagen att hjälpa till på rätt sätt.
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| 25. |
- Rader, Romina, et al.
(författare)
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Non-bee insects are important contributors to global crop pollination.
- 2016
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Ingår i: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 113:1, s. 146-151
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Tidskriftsartikel (refereegranskat)abstract
- Wild and managed bees are well documented as effective pollinators of global crops of economic importance. However, the contributions by pollinators other than bees have been little explored despite their potential to contribute to crop production and stability in the face of environmental change. Non-bee pollinators include flies, beetles, moths, butterflies, wasps, ants, birds, and bats, among others. Here we focus on non-bee insects and synthesize 39 field studies from five continents that directly measured the crop pollination services provided by non-bees, honey bees, and other bees to compare the relative contributions of these taxa. Non-bees performed 25-50% of the total number of flower visits. Although non-bees were less effective pollinators than bees per flower visit, they made more visits; thus these two factors compensated for each other, resulting in pollination services rendered by non-bees that were similar to those provided by bees. In the subset of studies that measured fruit set, fruit set increased with non-bee insect visits independently of bee visitation rates, indicating that non-bee insects provide a unique benefit that is not provided by bees. We also show that non-bee insects are not as reliant as bees on the presence of remnant natural or seminatural habitat in the surrounding landscape. These results strongly suggest that non-bee insect pollinators play a significant role in global crop production and respond differently than bees to landscape structure, probably making their crop pollination services more robust to changes in land use. Non-bee insects provide a valuable service and provide potential insurance against bee population declines.
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| 26. |
- Rasmussen, Claus, et al.
(författare)
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Evaluating competition for forage plants between honey bees and wild bees in Denmark
- 2021
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 16:4
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Tidskriftsartikel (refereegranskat)abstract
- A recurrent concern in nature conservation is the potential competition for forage plants between wild bees and managed honey bees. Specifically, that the highly sophisticated system of recruitment and large perennial colonies of honey bees quickly exhaust forage resources leading to the local extirpation of wild bees. However, different species of bees show different preferences for forage plants. We here summarize known forage plants for honey bees and wild bee species at national scale in Denmark. Our focus is on floral resources shared by honey bees and wild bees, with an emphasis on both threatened wild bee species and foraging specialist species. Across all 292 known bee species from Denmark, a total of 410 plant genera were recorded as forage plants. These included 294 plant genera visited by honey bees and 292 plant genera visited by different species of wild bees. Honey bees and wild bees share 176 plant genera in Denmark. Comparing the pairwise niche overlap for individual bee species, no significant relationship was found between their overlap and forage specialization or conservation status. Network analysis of the bee-plant interactions placed honey bees aside from most other bee species, specifically the module containing the honey bee had fewer links to any other modules, while the remaining modules were more highly inter-connected. Despite the lack of predictive relationship from the pairwise niche overlap, data for individual species could be summarized. Consequently, we have identified a set of operational parameters that, based on a high foraging overlap (>70%) and unfavorable conservation status (Vulnerable+Endangered+Critically Endangered), can guide both conservation actions and land management decisions in proximity to known or suspected populations of these species.
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| 27. |
- Rundlöf, Maj, et al.
(författare)
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Seed coating with a neonicotinoid insecticide negatively affects wild bees.
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 521:7550, s. 77-162
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the effects of neonicotinoid insecticides on bees is vital because of reported declines in bee diversity and distribution and the crucial role bees have as pollinators in ecosystems and agriculture. Neonicotinoids are suspected to pose an unacceptable risk to bees, partly because of their systemic uptake in plants, and the European Union has therefore introduced a moratorium on three neonicotinoids as seed coatings in flowering crops that attract bees. The moratorium has been criticized for being based on weak evidence, particularly because effects have mostly been measured on bees that have been artificially fed neonicotinoids. Thus, the key question is how neonicotinoids influence bees, and wild bees in particular, in real-world agricultural landscapes. Here we show that a commonly used insecticide seed coating in a flowering crop can have serious consequences for wild bees. In a study with replicated and matched landscapes, we found that seed coating with Elado, an insecticide containing a combination of the neonicotinoid clothianidin and the non-systemic pyrethroid β-cyfluthrin, applied to oilseed rape seeds, reduced wild bee density, solitary bee nesting, and bumblebee colony growth and reproduction under field conditions. Hence, such insecticidal use can pose a substantial risk to wild bees in agricultural landscapes, and the contribution of pesticides to the global decline of wild bees may have been underestimated. The lack of a significant response in honeybee colonies suggests that reported pesticide effects on honeybees cannot always be extrapolated to wild bees.
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| 28. |
- Tyler, Torbjörn, et al.
(författare)
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Climate warming and land-use changes drive broad-scale floristic changes in Southern Sweden
- 2018
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013. ; 24:6, s. 2607-2621
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Tidskriftsartikel (refereegranskat)abstract
- Land-use changes, pollution and climate warming during the 20th century havecaused changes in biodiversity across the world. However, in many cases, the environmental drivers are poorly understood. To identify and rank the drivers currentlycausing broad-scale floristic changes in N Europe, we analysed data from two vascularplant surveys of 200 randomly selected 2.5 9 2.5 km grid-squares in Scania,southernmost Sweden, conducted 1989–2006 and 2008–2015, respectively, andrelated the change in frequency (performance) of the species to a wide range ofspecies-specific plant traits. We chose traits representing all plausible drivers ofrecent floristic changes: climatic change (northern distribution limit, flowering time),land-use change (light requirement, response to grazing/mowing, response to soildisturbance), drainage (water requirement), acidification (pH optimum), nitrogendeposition and eutrophication (N requirement, N fixation ability, carnivory, parasitism,mycorrhizal associations), pollinator decline (mode of reproduction) andchanges in CO2 levels (photosynthetic pathway). Our results suggest that climatewarming and changes in land-use were the main drivers of changes in the flora duringthe last decades. Climate warming appeared as the most influential driver, withnorthern distribution limit explaining 30%–60% of the variance in the GLMM models.However, the relative importance of the drivers differed among habitat types,with grassland species being affected the most by cessation of grazing/mowing andspecies of ruderal habitats by on-going concentration of both agriculture and humanpopulation to the most productive soils. For wetland species, only pH optimum wassignificantly related to species performance, possibly an effect of the increasinghumification of acidic water bodies. An observed relative decline of mycorrhizal species may possibly be explained by decreasing nitrogen deposition resulting in lesscompetition for phosphorus. We found no effect of shortage or decline of pollinatinglepidopterans and bees.
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| 29. |
- Tyler, Torbjörn, et al.
(författare)
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Ecological indicator and traits values for Swedish vascular plants
- 2021
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Ingår i: Ecological Indicators. - : Elsevier. - 1470-160X .- 1872-7034. ; 120
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Tidskriftsartikel (refereegranskat)abstract
- We introduce and provide a new data-set of species-specific ecological indicator values (alternative 'Ellenberg values' for climatic variables, light, moisture, soil reaction/pH, salinity, nitrogen and phosphorus plus response to management and disturbance), physiological and reproductive traits (including symbionts, phenology, pollinators, nectar production, seed properties), indices of relevance for conservation (including introduction history and biodiversity relevance), and presence in 38 main vegetation types for all vascular plant species of Sweden based on a broad survey of published and unpublished data. The potential uses and limitations of the values, traits and indices are briefly outlined and discussed.
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| 30. |
- Tyler, Torbjörn, et al.
(författare)
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Utsådda blommor räddar inte insekterna
- 2021
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Ingår i: Svenska Dagbladet. - 1101-2412.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Om vi vill rädda hotade insektsarter är det miljöer med traditionella ängsväxter som vi behöver mer av, inte fröblandningar av oklart ursprung från handeln. Det skriver flera debattörer.
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