| 1. |
- Woodcock, B. A., et al.
(författare)
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Meta-analysis reveals that pollinator functional diversity and abundance enhance crop pollination and yield
- 2019
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- How insects promote crop pollination remains poorly understood in terms of the contribution of functional trait differences between species. We used meta-analyses to test for correlations between community abundance, species richness and functional trait metrics with oilseed rape yield, a globally important crop. While overall abundance is consistently important in predicting yield, functional divergence between species traits also showed a positive correlation. This result supports the complementarity hypothesis that pollination function is maintained by non-overlapping trait distributions. In artificially constructed communities (mesocosms), species richness is positively correlated with yield, although this effect is not seen under field conditions. As traits of the dominant species do not predict yield above that attributed to the effect of abundance alone, we find no evidence in support of the mass ratio hypothesis. Management practices increasing not just pollinator abundance, but also functional divergence, could benefit oilseed rape agriculture.
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| 2. |
- Garibaldi, Lucas A., et al.
(författare)
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Wild Pollinators Enhance Fruit Set of Crops Regardless of Honey Bee Abundance
- 2013
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 339:6127, s. 1608-1611
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Tidskriftsartikel (refereegranskat)abstract
- The diversity and abundance of wild insect pollinators have declined in many agricultural landscapes. Whether such declines reduce crop yields, or are mitigated by managed pollinators such as honey bees, is unclear. We found universally positive associations of fruit set with flower visitation by wild insects in 41 crop systems worldwide. In contrast, fruit set increased significantly with flower visitation by honey bees in only 14% of the systems surveyed. Overall, wild insects pollinated crops more effectively; an increase in wild insect visitation enhanced fruit set by twice as much as an equivalent increase in honey bee visitation. Visitation by wild insects and honey bees promoted fruit set independently, so pollination by managed honey bees supplemented, rather than substituted for, pollination by wild insects. Our results suggest that new practices for integrated management of both honey bees and diverse wild insect assemblages will enhance global crop yields.
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| 3. |
- Garibaldi, Lucas A., et al.
(författare)
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Trait matching of flower visitors and crops predicts fruit set better than trait diversity
- 2015
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Ingår i: Journal of Applied Ecology. - : Wiley. - 1365-2664 .- 0021-8901. ; 52:6, s. 1436-1444
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Forskningsöversikt (refereegranskat)abstract
- Understanding the relationships between trait diversity, species diversity and ecosystem functioning is essential for sustainable management. For functions comprising two trophic levels, trait matching between interacting partners should also drive functioning. However, the predictive ability of trait diversity and matching is unclear for most functions, particularly for crop pollination, where interacting partners did not necessarily co-evolve. World-wide, we collected data on traits of flower visitors and crops, visitation rates to crop flowers per insect species and fruit set in 469 fields of 33 crop systems. Through hierarchical mixed-effects models, we tested whether flower visitor trait diversity and/or trait matching between flower visitors and crops improve the prediction of crop fruit set (functioning) beyond flower visitor species diversity and abundance. Flower visitor trait diversity was positively related to fruit set, but surprisingly did not explain more variation than flower visitor species diversity. The best prediction of fruit set was obtained by matching traits of flower visitors (body size and mouthpart length) and crops (nectar accessibility of flowers) in addition to flower visitor abundance, species richness and species evenness. Fruit set increased with species richness, and more so in assemblages with high evenness, indicating that additional species of flower visitors contribute more to crop pollination when species abundances are similar.Synthesis and applications. Despite contrasting floral traits for crops world-wide, only the abundance of a few pollinator species is commonly managed for greater yield. Our results suggest that the identification and enhancement of pollinator species with traits matching those of the focal crop, as well as the enhancement of pollinator richness and evenness, will increase crop yield beyond current practices. Furthermore, we show that field practitioners can predict and manage agroecosystems for pollination services based on knowledge of just a few traits that are known for a wide range of flower visitor species. Despite contrasting floral traits for crops world-wide, only the abundance of a few pollinator species is commonly managed for greater yield. Our results suggest that the identification and enhancement of pollinator species with traits matching those of the focal crop, as well as the enhancement of pollinator richness and evenness, will increase crop yield beyond current practices. Furthermore, we show that field practitioners can predict and manage agroecosystems for pollination services based on knowledge of just a few traits that are known for a wide range of flower visitor species. Editor's Choice
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| 4. |
- Kennedy, Christina M., et al.
(författare)
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A global quantitative synthesis of local and landscape effects on wild bee pollinators in agroecosystems
- 2013
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 16:5, s. 584-599
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Bees provide essential pollination services that are potentially affected both by local farm management and the surrounding landscape. To better understand these different factors, we modelled the relative effects of landscape composition (nesting and floral resources within foraging distances), landscape configuration (patch shape, interpatch connectivity and habitat aggregation) and farm management (organic vs. conventional and local-scale field diversity), and their interactions, on wild bee abundance and richness for 39 crop systems globally. Bee abundance and richness were higher in diversified and organic fields and in landscapes comprising more high-quality habitats; bee richness on conventional fields with low diversity benefited most from high-quality surrounding land cover. Landscape configuration effects were weak. Bee responses varied slightly by biome. Our synthesis reveals that pollinator persistence will depend on both the maintenance of high-quality habitats around farms and on local management practices that may offset impacts of intensive monoculture agriculture.
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| 5. |
- Lichtenberg, Elinor M., et al.
(författare)
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A global synthesis of the effects of diversified farming systems on arthropod diversity within fields and across agricultural landscapes
- 2017
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 23:11, s. 4946-4957
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Tidskriftsartikel (refereegranskat)abstract
- Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than species richness, and whether impacts differ across spatial scales and landscape contexts. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity (communities within fields), and regional diversity (communities across fields) of arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in-field plant diversity enhanced arthropod abundance, particularly for rare taxa. This resulted in increased richness but decreased evenness. While these responses were stronger at local relative to regional scales, richness and abundance increased at both scales, and richness on farms embedded in complex relative to simple landscapes. Overall, both organic farming and in-field plant diversification exerted the strongest effects on pollinators and predators, suggesting these management schemes can facilitate ecosystem service providers without augmenting herbivore (pest) populations. Our results suggest that organic farming and plant diversification promote diverse arthropod metacommunities that may provide temporal and spatial stability of ecosystem service provisioning. Conserving diverse plant and arthropod communities in farming systems therefore requires sustainable practices that operate both within fields and across landscapes.
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| 6. |
- 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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| 7. |
- Albrecht, Matthias, et al.
(författare)
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The effectiveness of flower strips and hedgerows on pest control, pollination services and crop yield : a quantitative synthesis
- 2020
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 23:10, s. 1488-1498
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Tidskriftsartikel (refereegranskat)abstract
- Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future.
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| 8. |
- Allen-Perkins, Alfonso, et al.
(författare)
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CropPol : a dynamic, open and global database on crop pollination
- 2022
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Ingår i: Ecology. - : Wiley. - 0012-9658 .- 1939-9170. ; 103:3
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Tidskriftsartikel (refereegranskat)abstract
- Seventy five percent of the world's food crops benefit from insect pollination. Hence, there has been increased interest in how global change drivers impact this critical ecosystem service. Because standardized data on crop pollination are rarely available, we are limited in our capacity to understand the variation in pollination benefits to crop yield, as well as to anticipate changes in this service, develop predictions, and inform management actions. Here, we present CropPol, a dynamic, open and global database on crop pollination. It contains measurements recorded from 202 crop studies, covering 3,394 field observations, 2,552 yield measurements (i.e. berry weight, number of fruits and kg per hectare, among others), and 47,752 insect records from 48 commercial crops distributed around the globe. CropPol comprises 32 of the 87 leading global crops and commodities that are pollinator dependent. Malus domestica is the most represented crop (32 studies), followed by Brassica napus (22 studies), Vaccinium corymbosum (13 studies), and Citrullus lanatus (12 studies). The most abundant pollinator guilds recorded are honey bees (34.22% counts), bumblebees (19.19%), flies other than Syrphidae and Bombyliidae (13.18%), other wild bees (13.13%), beetles (10.97%), Syrphidae (4.87%), and Bombyliidae (0.05%). Locations comprise 34 countries distributed among Europe (76 studies), Northern America (60), Latin America and the Caribbean (29), Asia (20), Oceania (10), and Africa (7). Sampling spans three decades and is concentrated on 2001-05 (21 studies), 2006-10 (40), 2011-15 (88), and 2016-20 (50). This is the most comprehensive open global data set on measurements of crop flower visitors, crop pollinators and pollination to date, and we encourage researchers to add more datasets to this database in the future. This data set is released for non-commercial use only. Credits should be given to this paper (i.e., proper citation), and the products generated with this database should be shared under the same license terms (CC BY-NC-SA). This article is protected by copyright. All rights reserved.
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| 9. |
- 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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| 10. |
- Riggi, Laura, et al.
(författare)
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Early-season mass-flowering crop cover dilutes wild bee abundance and species richness in temperate regions : A quantitative synthesis
- 2024
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Ingår i: Journal of Applied Ecology. - 0021-8901 .- 1365-2664.
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Tidskriftsartikel (refereegranskat)abstract
- Pollinators benefit from increasing floral resources in agricultural landscapes, which could be an underexplored co-benefit of mass-flowering crop cultivation. However, the impacts of mass-flowering crops on pollinator communities are complex and appear to be context-dependent, mediated by factors such as crop flowering time and the availability of other flower resources in the landscape. A synthesis of research is needed to develop management recommendations for effective pollinator conservation in agroecosystems. By combining 22 datasets from 13 publications conducted in nine temperate countries (20 European, 2 North American), we investigated if mass-flowering crop flowering time (early or late season), bloom state (during or after crop flowering) and extent of non-crop habitat cover in the landscape moderated the effect of mass-flowering crop cover on wild pollinator abundance and species richness in mass-flowering crop and non-crop habitats. During bloom, wild bee abundance and richness are negatively related to mass-flowering crop cover. Dilution effects were predominant in crop habitats and early in the season, except for bumblebees, which declined with mass-flowering crop cover irrespective of habitat or season. Late in the season and in non-crop habitats, several of these negative relationships were either absent or reversed. Late-season mass-flowering crop cover is positively related to honeybee abundance in crop habitats and to other bee abundance in non-crop habitats. These results indicate that crop-adapted species, like honeybees, move to forage and concentrate on late-season mass-flowering crops at a time when flower availability in the landscape is limited, potentially alleviating competition for flower resources in non-crop habitats. We found no evidence of pollinators moving from mass-flowering crop to non-crop habitats after crop bloom. Synthesis and applications: Our results confirm that increasing early-season mass-flowering crop cover dilutes wild pollinators in crop habitats during bloom. We find that dilution effects were absent late in the season. While mass-flowering crop cultivation alone is unlikely to be sufficient for maintaining pollinators, as part of carefully designed diverse crop rotations or mixtures combined with the preservation of permanent non-crop habitats, it might provide valuable supplementary food resources for pollinators in temperate agroecosystems, particularly later in the season when alternative flower resources are scarce.
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| 11. |
- Senapathi, Deepa, et al.
(författare)
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Wild insect diversity increases inter-annual stability in global crop pollinator communities
- 2021
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Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954 .- 0962-8452. ; 288:1947
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Tidskriftsartikel (refereegranskat)abstract
- While an increasing number of studies indicate that the range, diversity and abundance of many wild pollinators has declined, the global area of pollinator-dependent crops has significantly increased over the last few decades. Crop pollination studies to date have mainly focused on either identifying different guilds pollinating various crops, or on factors driving spatial changes and turnover observed in these communities. The mechanisms driving temporal stability for ecosystem functioning and services, however, remain poorly understood. Our study quantifies temporal variability observed in crop pollinators in 21 different crops across multiple years at a global scale. Using data from 43 studies from six continents, we show that (i) higher pollinator diversity confers greater inter-annual stability in pollinator communities, (ii) temporal variation observed in pollinator abundance is primarily driven by the three-most dominant species, and (iii) crops in tropical regions demonstrate higher inter-annual variability in pollinator species richness than crops in temperate regions. We highlight the importance of recognizing wild pollinator diversity in agricultural landscapes to stabilize pollinator persistence across years to protect both biodiversity and crop pollination services. Short-term agricultural management practices aimed at dominant species for stabilizing pollination services need to be considered alongside longer term conservation goals focussed on maintaining and facilitating biodiversity to confer ecological stability.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Kleijn, David, et al.
(författare)
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Delivery of crop pollination services is an insufficient argument for wild pollinator conservation.
- 2015
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 6
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Tidskriftsartikel (refereegranskat)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.
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| 20. |
- Rundlöf, M., et al.
(författare)
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Application of the JKR method to the measurement of adhesion to Langmuir-Blodgett cellulose surfaces
- 2000
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 0021-9797 .- 1095-7103. ; 230:2, s. 441-447
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Tidskriftsartikel (refereegranskat)abstract
- The JKR method has been applied for studying adhesion between poly(dimethylsiloxane) (PDMS) caps and Langmuir-Blodgett cellulose surfaces including the substrate, hydrophobized mica, and two flat mineral surfaces, bare mica and glass, The self-adhesion of PDMS caps and oxidized PDMS caps are included as a reference to compare with literature data. The results of the measurements have been compared with previous studies using the surface force apparatus and similar systems. A satisfactory agreement is obtained for simple systems showing no, or very limited, hysteresis between loading and unloading curves, In several cases, however, a large hysteresis is found between loading and unloading curves, with a larger adhesion measured from the pull-off force than from the JKR-curve determined on loading. This is, for instance, the case for PDMS against cellulose. The situation is analogous to that found in wetting studies showing a large hysteresis between advancing and receding contact angles.
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| 21. |
- Rundlöf, Maj, et al.
(författare)
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Flower plantings support wild bee reproduction and may also mitigate pesticide exposure effects
- 2022
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Ingår i: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 59:8, s. 2117-2127
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Tidskriftsartikel (refereegranskat)abstract
- Sustainable agriculture relies on pollinators, and wild bees benefit yield of multiple crops. However, the combined exposure to pesticides and loss of flower resources, driven by agricultural intensification, contribute to declining diversity and abundance of many bee taxa. Flower plantings along the margins of agricultural fields offer diverse food resources not directly treated with pesticides. To investigate the potential of flower plantings to mitigate bee pesticide exposure effects and support bee reproduction, we selected replicated sites in intensively farmed landscapes where half contained flower plantings. We assessed solitary bee Osmia lignaria and bumble bee Bombus vosnesenskii nesting and reproduction throughout the season in these landscapes. We also quantified local and landscape flower resources and used bee-collected pollen to determine forage resource use and pesticide exposure and risk. Flower plantings, and their local flower resources, increased O. lignaria nesting probability. Bombus vosnesenskii reproduction was more strongly related to landscape than local flower resources. Bees at sites with and without flower plantings experienced similar pesticide risk, and the local flowers, alongside flowers in the landscape, were sources of pesticide exposure particularly for O. lignaria. However, local flower resources mitigated negative pesticide effects on B. vosnesenskii reproduction. Synthesis and applications. Bees in agricultural landscapes are threatened by pesticide exposure and loss of flower resources through agricultural intensification. Therefore, finding solutions to mitigate negative effects of pesticide use and flower deficiency is urgent. Our findings point towards flower plantings as a potential solution to support bee populations by mitigating pesticide exposure effects and providing key forage. Further investigation of the balance between forage benefits and added pesticide risk is needed to reveal contexts where net benefits occur.
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| 22. |
- Sponsler, Douglas B., et al.
(författare)
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Pesticides and pollinators : A socioecological synthesis
- 2019
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697. ; 662, s. 1012-1027
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Forskningsöversikt (refereegranskat)abstract
- The relationship between pesticides and pollinators, while attracting no shortage of attention from scientists, regulators, and the public, has proven resistant to scientific synthesis and fractious in matters of policy and public opinion. This is in part because the issue has been approached in a compartmentalized and intradisciplinary way, such that evaluations of organismal pesticide effects remain largely disjoint from their upstream drivers and downstream consequences. Here, we present a socioecological framework designed to synthesize the pesticide-pollinator system and inform future scholarship and action. Our framework consists of three interlocking domains-pesticide use, pesticide exposure, and pesticide effects–each consisting of causally linked patterns, processes, and states. We elaborate each of these domains and their linkages, reviewing relevant literature and providing empirical case studies. We then propose guidelines for future pesticide-pollinator scholarship and action agenda aimed at strengthening knowledge in neglected domains and integrating knowledge across domains to provide decision support for stakeholders and policymakers. Specifically, we emphasize (1) stakeholder engagement, (2) mechanistic study of pesticide exposure, (3) understanding the propagation of pesticide effects across levels of organization, and (4) full-cost accounting of the externalities of pesticide use and regulation. Addressing these items will require transdisciplinary collaborations within and beyond the scientific community, including the expertise of farmers, agrochemical developers, and policymakers in an extended peer community.
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| 23. |
- Askri, Dalel, et al.
(författare)
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A blood test to monitor bee health across a European network of agricultural sites of different land-use by MALDI BeeTyping mass spectrometry
- 2024
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Ingår i: Science of the Total Environment. - 0048-9697. ; 929
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Tidskriftsartikel (refereegranskat)abstract
- There are substantial concerns about impaired honey bee health and colony losses due to several poorly understood factors. We used MALDI profiling (MALDI BeeTyping®) analysis to investigate how some environmental and management factors under field conditions across Europe affected the honey bee haemolymph peptidome (all peptides in the circulatory fluid), as a profile of molecular markers representing the immune status of Apis mellifera. Honey bees were exposed to a range of environmental stressors in 128 agricultural sites across eight European countries in four biogeographic zones, with each country contributing eight sites each for two different cropping systems: oilseed rape (OSR) and apple (APP). The full haemolymph peptide profiles, including the presence and levels of three key immunity markers, namely the antimicrobial peptides (AMPs) Apidaecin, Abaecin and Defensin-1, allowed the honey bee responses to environmental variables to be discriminated by country, crop type and site. When considering just the AMPs, it was not possible to distinguish between countries by the prevalence of each AMP in the samples. However, it was possible to discriminate between countries on the amounts of the AMPs, with the Swedish samples in particular expressing high amounts of all AMPs. A machine learning model was developed to discriminate the haemolymphs of bees from APP and OSR sites. The model was 90.6 % accurate in identifying the crop type from the samples used to build the model. Overall, MALDI BeeTyping® of bee haemolymph represents a promising and cost-effective “blood test” for simultaneously monitoring dozens of peptide markers affected by environmental stressors at the landscape scale, thus providing policymakers with new diagnostic and regulatory tools for monitoring bee health.
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| 24. |
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| 25. |
- Bashir, J., et al.
(författare)
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The influence of Cr doping on the structural and magnetic properties of Sr2Fe1-xCrxMoO6 double perovskite
- 2006
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Ingår i: Physica. B, Condensed matter. - : Elsevier BV. - 0921-4526 .- 1873-2135. ; 385, s. 126-129
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Tidskriftsartikel (refereegranskat)abstract
- We have studied the effect of Cr substitution for Fe in Sr2Fe1-xCr,MoO6 (x <= 0.3) double perovskites. X-ray diffraction, neutron powder diffraction (NPD), magnetisation measurements as well as Mossbauer spectroscopy have been used to determine the structural and magnetic properties of these compounds. All these materials were found to crystallise with tetragonal symmetry. The main observed effect is a decrease with respect to the undoped composition, of the cationic order with Cr doping levels. Mossbauer spectroscopy measurement revealed that iron exists in high spin + 3 oxidation state.
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| 26. |
- Bernes, Claes, et al.
(författare)
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How are biodiversity and dispersal of species affected by the management of roadsides? A systematic map
- 2017
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Ingår i: Environmental Evidence. - : Springer Science and Business Media LLC. - 2047-2382. ; 6:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: In many parts of the world, roadsides are regularly managed for traffic-safety reasons. Hence, there are similarities between roadsides and certain other managed habitats, such as wooded pastures and mown or grazed grasslands. These habitats have declined rapidly in Europe during the last century. For many species historically associated with them, roadsides may function as new primary habitats or as dispersal corridors in fragmented landscapes. Current recommendations for roadside management to promote conservation values are largely based on studies of plants in semi-natural grasslands, although such areas often differ from roadsides in terms of environmental conditions and disturbance regimes. Moreover, roadsides provide habitat not only for plants but also for many insects. For these reasons, stakeholders in Sweden have emphasised the need for more targeted management recommendations, based on actual studies of roadside biodiversity. Methods: This systematic map provides an overview of the available evidence on how biodiversity is affected by various forms of roadside management, and how such management influences the dispersal of species along roads or roadsides. We searched for literature using 13 online publication databases, 4 search engines, 36 specialist websites and 5 literature reviews. Search terms were developed in English, Danish, Dutch, French, German, Norwegian, Spanish and Swedish. Identified articles were screened for relevance using criteria set out in a protocol. No geographical restrictions were applied, and all species and groups of organisms were considered. Descriptions of included studies are available in an Excel file, and also in an interactive GIS application that can be accessed at an external website. Results: Our searches identified more than 7000 articles. The 207 articles included after screening described 301 individual studies considered to be relevant. More than two-thirds of these studies were conducted in North America, with most of the rest performed in Europe. More than half of the studies were published in grey literature such as reports from agencies or consultants. The interventions most commonly studied were herbicide use, sowing and mowing, followed by soil amendments such as mulching and fertiliser additions. The outcomes most frequently reported were effects of interventions on the abundance or species richness of herbs/forbs, graminoids and woody plants. Effects on insects and birds were reported in 6 and 3% of the studies, respectively. Conclusions: This systematic map is based on a comprehensive and systematic screening of all available literature on the effects of roadside management on biodiversity and dispersal of species. As such it should be of value to a range of actors, including managers and policymakers. The map provides a key to finding concrete guidance for conservation- and restoration-oriented roadside management from published research. However, the map also highlights important knowledge gaps: little data was found for some geographical regions, research is heavily biased taxonomically towards plants, and no study was found on how species dispersal was affected by roadside management. The map could therefore be a source of inspiration for new research.
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| 27. |
- Bernes, Claes, et al.
(författare)
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How are biodiversity and dispersal of species affected by the management of roadsides? A systematic map protocol
- 2016
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Ingår i: Environmental Evidence. - : Springer Science and Business Media LLC. - 2047-2382. ; 5:4
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Tidskriftsartikel (refereegranskat)abstract
- Background: In many parts of the world, roadsides are regularly managed for traffic-safety reasons. Hence, there are similarities between roadsides and certain other managed habitats, such as wooded pastures and mown or grazed grasslands. In contrast to roadsides, the latter habitats have declined rapidly in Europe during the last century, and today only a fraction of their former extent remains. For many species historically associated with these habitats, roadsides may therefore function as new primary habitats or as dispersal corridors in fragmented landscapes. Current recommendations for roadside management to promote conservation values are largely based on studies of plants in semi-natural grasslands, although such areas often differ from roadsides in terms of environmental factors and impacts. Moreover, roadsides provide habitats not only for plants but also for many insects, especially if they are sandy and exposed to the sun. For these reasons, stakeholders in Sweden have emphasised the need for more targeted management recommendations, based on actual studies of roadside biodiversity. Methods: The proposed systematic map is intended to provide an overview of the available evidence on how biodiversity is affected by various forms of roadside management, and how such management influences the dispersal of species along roads or roadsides. Relevant interventions include e.g. mowing, shrub removal, control of invasive/nuisance species, sowing or planting, burning, grazing by livestock, scraping and ditching. Non-intervention or alternative forms of roadside management will be used as comparators. Relevant outcomes include measures of species or genetic diversity, the abundance of individual species or groups of organisms, species distribution patterns, and movement rates of individuals or propagules. Searches will be made for peer-reviewed and grey literature in English and several other languages. No geographical restrictions will be applied, and all species and species groups will be considered.
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| 28. |
- Blasi, Maria, et al.
(författare)
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Evaluating predictive performance of statistical models explaining wild bee abundance in a mass-flowering crop
- 2021
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Ingår i: Ecography. - : Wiley. - 0906-7590 .- 1600-0587. ; 44:4, s. 525-536
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Tidskriftsartikel (refereegranskat)abstract
- Wild bee populations are threatened by current agricultural practices in many parts of the world, which may put pollination services and crop yields at risk. Loss of pollination services can potentially be predicted by models that link bee abundances with landscape-scale land-use, but there is little knowledge on the degree to which these statistical models are transferable across time and space. This study assesses the transferability of models for wild bee abundance in a mass-flowering crop across space (from one region to another) and across time (from one year to another). The models used existing data on bumblebee and solitary bee abundance in winter oilseed rape fields, together with high-resolution land-use crop-cover and semi-natural habitats data, from studies conducted in five different regions located in four countries (Sweden, Germany, Netherlands and the UK), in three different years (2011, 2012, 2013). We developed a hierarchical model combining all studies and evaluated the transferability using cross-validation. We found that both the landscape-scale cover of mass-flowering crops and permanent semi-natural habitats, including grasslands and forests, are important drivers of wild bee abundance in all regions. However, while the negative effect of increasing mass-flowering crops on the density of the pollinators is consistent between studies, the direction of the effect of semi-natural habitat is variable between studies. The transferability of these statistical models is limited, especially across regions, but also across time. Our study demonstrates the limits of using statistical models in conjunction with widely available land-use crop-cover classes for extrapolating pollinator density across years and regions, likely in part because input variables such as cover of semi-natural habitats poorly capture variability in pollinator resources between regions and years.
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| 29. |
- Bottero, Irene, et al.
(författare)
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Impact of landscape configuration and composition on pollinator communities across different European biogeographic regions
- 2023
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Ingår i: Frontiers in Ecology and Evolution. - 2296-701X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Heterogeneity in composition and spatial configuration of landscape elements support diversity and abundance of flower-visiting insects, but this is likely dependent on taxonomic group, spatial scale, weather and climatic conditions, and is particularly impacted by agricultural intensification. Here, we analyzed the impacts of both aspects of landscape heterogeneity and the role of climatic and weather conditions on pollinating insect communities in two economically important mass-flowering crops across Europe. Methods: Using a standardized approach, we collected data on the abundance of five insect groups (honey bees, bumble bees, other bees, hover flies and butterflies) in eight oilseed rape and eight apple orchard sites (in crops and adjacent crop margins), across eight European countries (128 sites in total) encompassing four biogeographic regions, and quantified habitat heterogeneity by calculating relevant landscape metrics for composition (proportion and diversity of land-use types) and configuration (the aggregation and isolation of land-use patches). Results: We found that flower-visiting insects responded to landscape and climate parameters in taxon- and crop-specific ways. For example, landscape diversity was positively correlated with honey bee and solitary bee abundance in oilseed rape fields, and hover fly abundance in apple orchards. In apple sites, the total abundance of all pollinators, and particularly bumble bees and solitary bees, decreased with an increasing proportion of orchards in the surrounding landscape. In oilseed rape sites, less-intensively managed habitats (i.e., woodland, grassland, meadows, and hedgerows) positively influenced all pollinators, particularly bumble bees and butterflies. Additionally, our data showed that daily and annual temperature, as well as annual precipitation and precipitation seasonality, affects the abundance of flower-visiting insects, although, again, these impacts appeared to be taxon- or crop-specific. Discussion: Thus, in the context of global change, our findings emphasize the importance of understanding the role of taxon-specific responses to both changes in land use and climate, to ensure continued delivery of pollination services to pollinator-dependent crops.
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| 30. |
- Caballero-Lopez, B., et al.
(författare)
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Aphids and their natural enemies are differently affected by habitat features at local and landscape scales
- 2012
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Ingår i: Biological Control. - : Elsevier BV. - 1090-2112 .- 1049-9644. ; 63:2, s. 222-229
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Tidskriftsartikel (refereegranskat)abstract
- Biological control, an essential ecosystem service to agriculture, can be affected by ecological processes operating at landscape scales. Here we assessed the effect of landscape complexity, measured as proportion of arable land (PAL), on the abundance of aphids, parasitoids, and specialist and generalist predators. In addition we set up cage experiments to test the ability of these groups of enemies to suppress aphid densities. Landscape context did not significantly explain differences in aphid or parasitoid densities between fields. However, aphid densities were significantly higher in field interior compared to the margin. Coccinellid (specialist predator) abundance showed a similar pattern, with higher density in the field interior, indicating an aggregative response to aphid prey. In addition, Coccinellid abundance increased with PAL but only in field interiors and not at the field margins. The abundance of carabids (generalist predators) increased with PAL, suggesting that they benefit from landscape simplification. The cage experiment revealed that specialist as well as generalist predators were able to reduce the number of aphids on barley tillers and that a combination of both guilds did not provide a greater reduction of aphids. Our results suggest higher densities of generalist predators with increasing PAL Nonetheless, the greater abundance of coccinellids and carabid beetles in cereal fields embedded in simple landscapes does not necessarily imply better pest control since natural enemies may compete, thereby limiting their ability to control pests. (C) 2012 Elsevier Inc. All rights reserved.
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| 31. |
- Cole, Lorna J., et al.
(författare)
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A critical analysis of the potential for EU Common Agricultural Policy measures to support wild pollinators on farmland
- 2020
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Ingår i: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 57:4, s. 681-694
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Tidskriftsartikel (refereegranskat)abstract
- Agricultural intensification and associated loss of high-quality habitats are key drivers of insect pollinator declines. With the aim of decreasing the environmental impact of agriculture, the 2014 EU Common Agricultural Policy (CAP) defined a set of habitat and landscape features (Ecological Focus Areas: EFAs) farmers could select from as a requirement to receive basic farm payments. To inform the post-2020 CAP, we performed a European-scale evaluation to determine how different EFA options vary in their potential to support insect pollinators under standard and pollinator-friendly management, as well as the extent of farmer uptake. A structured Delphi elicitation process engaged 22 experts from 18 European countries to evaluate EFAs options. By considering life cycle requirements of key pollinating taxa (i.e. bumble bees, solitary bees and hoverflies), each option was evaluated for its potential to provide forage, bee nesting sites and hoverfly larval resources. EFA options varied substantially in the resources they were perceived to provide and their effectiveness varied geographically and temporally. For example, field margins provide relatively good forage throughout the season in Southern and Eastern Europe but lacked early-season forage in Northern and Western Europe. Under standard management, no single EFA option achieved high scores across resource categories and a scarcity of late season forage was perceived. Experts identified substantial opportunities to improve habitat quality by adopting pollinator-friendly management. Improving management alone was, however, unlikely to ensure that all pollinator resource requirements were met. Our analyses suggest that a combination of poor management, differences in the inherent pollinator habitat quality and uptake bias towards catch crops and nitrogen-fixing crops severely limit the potential of EFAs to support pollinators in European agricultural landscapes. Policy Implications. To conserve pollinators and help protect pollination services, our expert elicitation highlights the need to create a variety of interconnected, well-managed habitats that complement each other in the resources they offer. To achieve this the Common Agricultural Policy post-2020 should take a holistic view to implementation that integrates the different delivery vehicles aimed at protecting biodiversity (e.g. enhanced conditionality, eco-schemes and agri-environment and climate measures). To improve habitat quality we recommend an effective monitoring framework with target-orientated indicators and to facilitate the spatial targeting of options collaboration between land managers should be incentivised.
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| 32. |
- Enberg, Sofia, et al.
(författare)
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The influence of process conditions during pulp storage on the optical properties of Norway spruce high-yield pulps
- 2009
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Ingår i: Proceedings - 2009 International Mechanical Pulping Conference, IMPC 2009. ; , s. 117-121
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Konferensbidrag (refereegranskat)abstract
- The present study is part of a larger work aiming at establishing the knowledge basis needed to develop cost-effective processes for producing high-bright mechanical and chemimechanical pulps. The influence of process conditions (time, pH, temperature, consistency) on the optical properties during pulp storage of a well-washed hydrogen peroxide bleached Norway spruce pulp has been examined. The general effect of storage was darkening of the pulp due to an increase in light absorption, especially at shorter wavelengths. Time and temperature were found to be the process variables that had the largest impact, the trends were similar independent of pH and pulp consistency. The light scattering ability increased initially, giving a positive contribution to brightness. This indicates that the storage also resulted in a change in sheet structure.
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| 33. |
- Eriksson, Annika, 1975, et al.
(författare)
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High temperature phase transition of the magnetoelectric double perovskite Sr2NiMoO6 by neutron diffraction
- 2006
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Ingår i: Materials Research Bulletin. - 0025-5408. ; 41, s. 144-157
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Tidskriftsartikel (refereegranskat)abstract
- The magnetic ferroelectric double perovskite Sr2NiMoO6 has been characterised using neutron powder diffraction (NPD) data and magnetic susceptibility measurements. High temperature NPD data indicate that the material undergoes a continuous structural phase transition from tetragonal (I4/m) to cubic (Fm(3) over barm) at approximately 550 K. The transition is linked to the level of rotation of the NiO6 and MoO6 octahedra, which form perfectly segregated sub-lattices in the material. The reduction in symmetry at 550 K is linked to the onset of a spontaneous dipole in the material allowing the structural perturbation to be described as an improper ferroelectric phase transition. The appearance of low angle reflections in the 20 K dataset indicates the presence of an antiferromagnetic ordered around state. The magnetic moment was refined to 1.88(8) mu(B) confirming that the magnetism originates from the Ni2+ (S = 1) ions. (C) 2005 Elsevier Ltd. All rights reserved.
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| 34. |
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| 35. |
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| 36. |
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| 37. |
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| 38. |
- Frantti, J., Ivanov,S. A., Eriksson, .S- G. Rundlöf, H. Lantto, V. Lappalainen, J. and Kakihana, M.
(författare)
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High resolution neutron powder diffraction study of the microstrain contributions in Pb(ZrxTi1
- 2002
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Ingår i: Proceeding at the Electroceramics VIII Conference, August 25-28 2002, Rome, Italy.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 39. |
- Frantti, J., Ivanov, S. A., Eriksson, S.- G., Rundlöf, H., Lantto,V.Lappalainen, J. and Kakihana, M.
(författare)
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On the phase transitions of Pb(ZrxTi1
- 2002
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Ingår i: Phys. Rev.. ; B66, s. 64108-
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Tidskriftsartikel (refereegranskat)
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| 40. |
- Frantti, J., Ivanov, S., Eriksson, S., Rundlöf, H., Lantto, V., Lappalainen, J. and Kakihana, M.
(författare)
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Phase transitions of Pb(ZrxTi1
- 2002
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Ingår i: Phys. Rev.. ; B66, s. 64108-
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Tidskriftsartikel (refereegranskat)
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| 41. |
- Frantti, J., Ivanov S., Lappalainen, J., Eriksson, S., Lantto, V., Nishio, S., Kakihana, M. and Rundlöf, H.
(författare)
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Local and average structure of lead titanate based ceramics
- 2002
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Ingår i: Ferroelectrics. ; 266, s. 73-
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Tidskriftsartikel (refereegranskat)
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| 42. |
- Frantti, J, et al.
(författare)
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Local and average structure of lead titanate based ceramics
- 2002
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Ingår i: Ferroelectrics. - : Informa UK Limited. - 0015-0193 .- 1563-5112. ; 266:1, s. 73-90
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Tidskriftsartikel (refereegranskat)abstract
- The revised lattice dynamics of Pb(Zr x Ti 1 -x )O 3 (PZT) with 0.10 ≤ x ≤0.54 ceramics is reported. The phase transition from tetragonal phase to the monoclinic phase is proposed to occur via locally distorted regions. Neutron diffraction data suggests that these local regions transform to the monoclinic phase with decreasing temperature, when x ≈0.50.
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| 43. |
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| 44. |
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| 45. |
- 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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| 46. |
- 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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| 47. |
- Hodge, Simon, et al.
(författare)
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Design and Planning of a Transdisciplinary Investigation into Farmland Pollinators : Rationale, Co-Design, and Lessons Learned
- 2022
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Ingår i: Sustainability (Switzerland). - : MDPI AG. - 2071-1050. ; 14:17
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Tidskriftsartikel (refereegranskat)abstract
- To provide a complete portrayal of the multiple factors negatively impacting insects in agricultural landscapes it is necessary to assess the concurrent incidence, magnitude, and interactions among multiple stressors over substantial biogeographical scales. Trans-national ecological field investigations with wide-ranging stakeholders typically encounter numerous challenges during the design planning stages, not least that the scientific soundness of a spatially replicated study design must account for the substantial geographic and climatic variation among distant sites. ‘PoshBee’ (Pan-European assessment, monitoring, and mitigation of Stressors on the Health of Bees) is a multi-partner transdisciplinary agroecological project established to investigate the suite of stressors typically encountered by pollinating insects in European agricultural landscapes. To do this, PoshBee established a network of 128 study sites across eight European countries and collected over 50 measurements and samples relating to the nutritional, toxicological, pathogenic, and landscape components of the bees’ environment. This paper describes the development process, rationale, and end-result of each aspect of the of the PoshBee field investigation. We describe the main issues and challenges encountered during the design stages and highlight a number of actions or processes that may benefit other multi-partner research consortia planning similar large-scale studies. It was soon identified that in a multi-component study design process, the development of interaction and communication networks involving all collaborators and stakeholders requires considerable time and resources. It was also necessary at each planning stage to be mindful of the needs and objectives of all stakeholders and partners, and further challenges inevitably arose when practical limitations, such as time restrictions and labour constraints, were superimposed upon prototype study designs. To promote clarity for all stakeholders, for each sub-component of the study, there should be a clear record of the rationale and reasoning that outlines how the final design transpired, what compromises were made, and how the requirements of different stakeholders were accomplished. Ultimately, multi-national agroecological field studies such as PoshBee benefit greatly from the involvement of diverse stakeholders and partners, ranging from field ecologists, project managers, policy legislators, mathematical modelers, and farmer organisations. While the execution of the study highlighted the advantages and benefits of large-scale transdisciplinary projects, the long planning period emphasized the need to formally describe a design framework that could facilitate the design process of future multi-partner collaborations.
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| 48. |
- Holzschuh, Andrea, et al.
(författare)
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Mass-flowering crops dilute pollinator abundance in agricultural landscapes across Europe
- 2016
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; , s. 1228-1236
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Tidskriftsartikel (refereegranskat)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.
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| 49. |
- Ivanov, SA, et al.
(författare)
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Structural and magnetic study of magnetoelectric perovskite Sr2CoMoO6
- 2006
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Ingår i: ZEITSCHRIFT FUR KRISTALLOGRAPHIE 537-542 Part 2 Suppl. 23, 2006. ; :2, s. 537-542
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Tidskriftsartikel (refereegranskat)abstract
- A study of the crystal and magnetic structure of the double perovskite Sr2CoMoO6 has been carried out on a polycrystalline sample using neutron diffraction (NPD) data between 10-700K. An analysis of NPD patterns at 295K has shown that this compound crystallizes in the tetragonal space group 14/m with a = 5.5616(l) and c = 7.9470(2) angstrom and has a 1:1 ordered arrangement of the B-sites. This compound undergoes a 14/m -> Fm3m improper ferroelectric phase transition near 563 K. A low-temperature antiferomagnetic ordering (below T-N = 37 K) has been followed from a sequence of low-temperature NPD data sets. The magnetic structure is defined by the propagation vector (k) over right arrow = (1/2,0,1/2). Alongside the obtained experimental results on magnetic and electric properties some aspects of magnetoelectricity in this perovskite is also discussed.
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| 50. |
- LAURENT, Marion, et al.
(författare)
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Novel indices reveal that pollinator exposure to pesticides varies across biological compartments and crop surroundings
- 2024
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Ingår i: Science of the Total Environment. - 0048-9697. ; 927
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Tidskriftsartikel (refereegranskat)abstract
- Declines in insect pollinators have been linked to a range of causative factors such as disease, loss of habitats, the quality and availability of food, and exposure to pesticides. Here, we analysed an extensive dataset generated from pesticide screening of foraging insects, pollen-nectar stores/beebread, pollen and ingested nectar across three species of bees collected at 128 European sites set in two types of crop. In this paper, we aimed to (i) derive a new index to summarise key aspects of complex pesticide exposure data and (ii) understand the links between pesticide exposures depicted by the different matrices, bee species and apple orchards versus oilseed rape crops. We found that summary indices were highly correlated with the number of pesticides detected in the related matrix but not with which pesticides were present. Matrices collected from apple orchards generally contained a higher number of pesticides (7.6 pesticides per site) than matrices from sites collected from oilseed rape crops (3.5 pesticides), with fungicides being highly represented in apple crops. A greater number of pesticides were found in pollen-nectar stores/beebread and pollen matrices compared with nectar and bee body matrices. Our results show that for a complete assessment of pollinator pesticide exposure, it is necessary to consider several different exposure routes and multiple species of bees across different agricultural systems.
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