| 1. |
- 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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| 2. |
- Banks, John E., et al.
(författare)
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Aphid parasitoids respond to vegetation heterogeneity but not to fragmentation scale: An experimental field study
- 2016
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791 .- 1618-0089. ; 17, s. 438-446
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Tidskriftsartikel (refereegranskat)abstract
- How animal populations respond to habitat manipulations is a central theme in ecology. In recent years, the role that vegetation heterogeneity plays in regulating arthropod populations has received particular attention in both conservation science and agricultural ecology. Numerous observational studies have demonstrated that herbivores and their natural enemies are sensitive to vegetation heterogeneity, but the individual effects of percentage land cover, degree of fragmentation and patch size remain little understood. We present here the results of a manipulative field experiment that explicitly' incorporates both habitat heterogeneity and the degree to which that heterogeneity is fragmented in order to determine the effects of each factor on parasitism in an agroecosystem, We deployed combinations of broccoli (crop) and weedy vegetation (non-crop) in linear arrays that varied in their percentage devoted to crop and in the degree at which crop patches were fragmented with weeds, and recorded parasitism rates on two aphid species multiple times during two years. Parasitoids responded to the percentage of crop in plots, but not to the spatial scale at which they were fragmented. Our results suggest that vegetation heterogeneity may be more important than fragmentation scale in biological control by, parasitoids.
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| 3. |
- Bartomeus, Ignasi, et al.
(författare)
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Pollinators, pests and soil properties interactively shape oilseed rape yield
- 2015
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791 .- 1618-0089. ; 16, s. 737-745
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Tidskriftsartikel (refereegranskat)abstract
- Pollination, pest control, and soil properties are well known to affect agricultural production. These factors might interactively shape crop yield, but most studies focus on only one of these factors at a time. We used 15 winter oilseed rape (Brass/co napus L.) fields in Sweden to study how variation among fields in pollinator visitation rates, pollen beetle attack rates and soil properties (soil texture, pH and organic carbon) interactively determined crop yield. The fields were embedded in a landscape gradient with contrasting proportions of arable and semi-natural land. In general, pollinator visitation and pest levels were negatively correlated and varied independently of soil properties. This may reflect that above- and below-ground processes react at landscape and local spatial scales, respectively. The above-ground biotic interactions and below-ground abiotic factors interactively affected crop yield. Pollinator visitation was the strongest predictor positively associated with yield. High soil pH also benefited yield, but only at tower pest loads. Surprisingly, high pest loads increased the pollinator benefits for yield. Implementing management plans at different spatial scales can create synergies among above- and below-ground ecosystem processes, hut both scales are needed given that different processes react al different sptitial scales.
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| 4. |
- Birkhofer, Klaus, et al.
(författare)
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Methods to identify the prey of invertebrate predators in terrestrial field studies
- 2017
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 7:6, s. 1942-1953
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Tidskriftsartikel (refereegranskat)abstract
- Predation is an interaction during which an organism kills and feeds on another organism. Past and current interest in studying predation in terrestrial habitats has yielded a number of methods to assess invertebrate predation events in terrestrial ecosystems. We provide a decision tree to select appropriate methods for individual studies. For each method, we then present a short introduction, key examples for applications, advantages and disadvantages, and an outlook to future refinements. Video and, to a lesser extent, live observations are recommended in studies that address behavioral aspects of predator-prey interactions or focus on per capita predation rates. Cage studies are only appropriate for small predator species, but often suffer from a bias via cage effects. The use of prey baits or analyses of prey remains are cheaper than other methods and have the potential to provide per capita predation estimates. These advantages often come at the cost of low taxonomic specificity. Molecular methods provide reliable estimates at a fine level of taxonomic resolution and are free of observer bias for predator species of any size. However, the current PCR-based methods lack the ability to estimate predation rates for individual predators and are more expensive than other methods. Molecular and stable isotope analyses are best suited to address systems that include a range of predator and prey species. Our review of methods strongly suggests that while in many cases individual methods are sufficient to study specific questions, combinations of methods hold a high potential to provide more holistic insights into predation events. This review presents an overview of methods to researchers that are new to the field or to particular aspects of predation ecology and provides recommendations toward the subset of suitable methods to identify the prey of invertebrate predators in terrestrial field research.
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| 5. |
- 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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| 6. |
- Dainese, Matteo, et al.
(författare)
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A global synthesis reveals biodiversity-mediated benefits for crop production
- 2019
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Ingår i: Science Advances. - : American Association for the Advancement of Science (AAAS). - 2375-2548. ; 5:10
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Tidskriftsartikel (refereegranskat)abstract
- Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield-related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society. Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).
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| 7. |
- Gagic, Vesna, et al.
(författare)
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Combined effects of agrochemicals and ecosystem services on crop yield across Europe
- 2017
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 20:11, s. 1427-1436
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Tidskriftsartikel (refereegranskat)abstract
- Simultaneously enhancing ecosystem services provided by biodiversity below and above ground is recommended to reduce dependence on chemical pesticides and mineral fertilisers in agriculture. However, consequences for crop yield have been poorly evaluated. Above ground, increased landscape complexity is assumed to enhance biological pest control, whereas below ground, soil organic carbon is a proxy for several yield-supporting services. In a field experiment replicated in 114 fields across Europe, we found that fertilisation had the strongest positive effect on yield, but hindered simultaneous harnessing of below- and above-ground ecosystem services. We furthermore show that enhancing natural enemies and pest control through increasing landscape complexity can prove disappointing in fields with low soil services or in intensively cropped regions. Thus, understanding ecological interdependences between land use, ecosystem services and yield is necessary to promote more environmentally friendly farming by identifying situations where ecosystem services are maximised and agrochemical inputs can be reduced.
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| 8. |
- Gagic, Vesna
(författare)
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Community variability in aphid parasitoids versus predators in response to agricultural intensification
- 2014
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Ingår i: Insect Conservation and Diversity. - : Wiley. - 1752-458X .- 1752-4598. ; 7, s. 103-112
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Tidskriftsartikel (refereegranskat)abstract
- Agricultural intensification (AI) is a great threat to biodiversity and its negative effects on species richness of different communities have been repeatedly shown. The effects of AI on community composition and variability, however, are important for assessing the predictability of community responses, but have rarely been studied simultaneously and across different taxonomic groups. In this study, we focused on parasitoids (primary and secondary) and predators (hoverflies and carabid beetles) of aphids in winter wheat fields with contrasting AI regimes (low AI, i.e. organic fields in structurally complex landscapes vs. high AI, i.e. conventional fields in structurally simple landscapes). We found divergence in species composition of more specialised, low-dispersing primary and secondary parasitoids within high AI fields, probably due to the disruption of the exchanges of species between local populations in structurally simple landscapes. In contrast, species composition of less specialised, highly dispersing carabid beetles and hoverflies converged in fields with high AI, where they were characterised by the dominance of a single, vagile species adapted to high land-use conditions. Furthermore, temporal community shifts were only pronounced in primary parasitoids and hoverflies, with higher temporal changes in fields with high AI in primary parasitoids. Collectively, our results illustrate that environmental homogenisation due to AI does not necessarily induce spatio-temporal homogenisation of communities, but rather can have contrasting effects on more specialised, low-dispersive parasitoids versus more generalised, high-dispersive predators, thereby demonstrating great differences in the predictability of responses to AI among aphid natural enemies
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| 9. |
- Gagic, Vesna, et al.
(författare)
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Interactive effects of pests increase seed yield
- 2016
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 6, s. 2149-2157
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Tidskriftsartikel (refereegranskat)abstract
- Loss in seed yield and therefore decrease in plant fitness due to simultaneous attacks by multiple herbivores is not necessarily additive, as demonstrated in evolutionary studies on wild plants. However, it is not clear how this transfers to crop plants that grow in very different conditions compared to wild plants. Nevertheless, loss in crop seed yield caused by any single pest is most often studied in isolation although crop plants are attacked by many pests that can cause substantial yield losses. This is especially important for crops able to compensate and even overcompensate for the damage. We investigated the interactive impacts on crop yield of four insect pests attacking different plant parts at different times during the cropping season. In 15 oilseed rape fields in Sweden, we estimated the damage caused by seed and stem weevils, pollen beetles, and pod midges. Pest pressure varied drastically among fields with very low correlation among pests, allowing us to explore interactive impacts on yield from attacks by multiple species. The plant damage caused by each pest species individually had, as expected, either no, or a negative impact on seed yield and the strongest negative effect was caused by pollen beetles. However, seed yield increased when plant damage caused by both seed and stem weevils was high, presumably due to the joint plant compensatory reaction to insect attack leading to overcompensation. Hence, attacks by several pests can change the impact on yield of individual pest species. Economic thresholds based on single species, on which pest management decisions currently rely, may therefore result in economically suboptimal choices being made and unnecessary excessive use of insecticides.
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| 10. |
- Gagic, Vesna, et al.
(författare)
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Landscape complexity is not a major trigger of species richness and food web structure of European cereal aphid parasitoids
- 2015
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Ingår i: BioControl. - : Springer Science and Business Media LLC. - 1386-6141 .- 1573-8248. ; 60, s. 451-461
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Tidskriftsartikel (refereegranskat)abstract
- In fragmented farmland landscapes structural complexity and low agricultural intensification should decrease the abundance of crop aphids due to increased abundances and species diversity of aphid enemies, including hymenopteran parasitoids. Here we study the effects of landscape structure and agricultural intensification on parasitism rates, abundances, and species richness of aphids and their parasitoids in five different regions in Europe. While total aphid numbers did not differ significantly among regions, we observed marked differences between Scandinavian and central European sites with respect to the species composition of aphids and their parasitoids and parasitism rates. In the cross country comparison landscape complexity and agricultural intensification did not significantly affect total aphid densities, although we observed species-specific reactions to land use. We also observed a tendency towards increased parasitoid species richness at low agricultural intensification but not at high landscape structure.
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| 11. |
- Gagic, Vesna
(författare)
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Landscape composition and configuration influence cereal aphid-parasitoid-hyperparasitoid interactions and biological control differentially across years
- 2014
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 183, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- The loss of landscape heterogeneity through agricultural intensification is known to affect aphid-parasitoid-hyperparasitoid interactions, with consequences for biological control. Various aspects of landscape heterogeneity (e.g. landscape composition and configuration) are expected to affect these interactions differentially, but there were few attempts to empirically compare the influence of separate landscape features on pest-parasitoid dynamics. To address these questions, we conducted three simultaneous studies in wheat fields in northern Serbia, to compare the effects of contrasting landscape contexts: (1) simple vs. more complex landscapes; (2) large- vs. small-field landscapes; (3) large-field areas with contrasting character of their marginal vegetation. We (1) found that aphid densities, parasitism rates and species richness of parasitoids and hyperparasitoids were higher in landscapes with more extensive and diversified non-crop habitats, positively affecting the biological control. We (2) did not find significant differences in aphid abundance and parasitism between large- and small-field landscapes, but we detected some contradictory patterns in aphid growth and parasitism increase; we relate both findings to certain region-specific landscape features of wider relevance. The character of marginal vegetation (3) had mixed effects on aphid-parasitoid interactions and dynamics, with respect to source of colonization. Parasitism rates above 22-24% were associated with population decline in the aphids, consistently across analyzed landscape contrasts. Other relationships were subject to significant inter-annual variability (over 2-4 years period), suggesting that effectiveness of landscape management for conservation biological control would also fluctuate year by year. Our findings show that a well-founded landscape-scale management for biological pest control in agriculture must be adjusted for differential aspects of landscape heterogeneity effects on pest-parasitoid interactions. (C) 2013 Elsevier B.V. All rights reserved.
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| 12. |
- 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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| 13. |
- Kendall, Liam K., et al.
(författare)
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Initial floral visitor identity and foraging time strongly influence blueberry reproductive success
- 2022
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Ingår i: Basic and Applied Ecology. - : Elsevier BV. - 1439-1791. ; 60, s. 114-122
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Tidskriftsartikel (refereegranskat)abstract
- Priority effects occur when the order of species arrival affects subsequent ecological processes. The order that pollinator species visit flowers may affect pollination through a priority effect, whereby the first visitor reduces or modifies the contribution of subsequent visits. We observed floral visitation to blueberry flowers from honeybees, stingless bees or a mixture of both species and investigated how (i) initial visits differed in duration to later visits; and (ii) how visit sequences from different pollinator taxa influenced fruit weight. Stingless bees visited blueberry flowers for significantly longer than honeybees and maintained their floral visit duration, irrespective of the number of preceding visits. In contrast, honeybee visit duration declined significantly with an increasing number of preceding visits. Fruit weight was positively associated with longer floral visit duration by honeybees but not from stingless bee or mixed species visitation. Fruit from mixed species visits were heavier overall than single species visits, because of a strong priority effect. An initial visit by a stingless bee fully pollinated the flower, limiting the pollination contribution of future visitors. However, after an initial honeybee visit, flowers were not fully pollinated and additional visitation had an additive effect upon fruit weight. Blueberries from flowers visited first by stingless bees were 60% heavier than those visited first by honeybees when total floral visitation was short (∼1 min). However, when total visitation time was long (∼ 8 min), blueberry fruit were 24% heavier when initial visits were from honeybees. Our findings highlight that the initial floral visit can have a disproportionate effect on pollination outcomes. Considering priority effects alongside traditional measures of pollinator effectiveness will provide a greater mechanistic understanding of how pollinator communities influence plant reproductive success.
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| 14. |
- Martin, Emily A., et al.
(författare)
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The interplay of landscape composition and configuration: new pathways to manage functional biodiversity and agroecosystem services across Europe
- 2019
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 22:7, s. 1083-1094
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Tidskriftsartikel (refereegranskat)abstract
- Managing agricultural landscapes to support biodiversity and ecosystem services is a key aim of a sustainable agriculture. However, how the spatial arrangement of crop fields and other habitats in landscapes impacts arthropods and their functions is poorly known. Synthesising data from 49 studies (1515 landscapes) across Europe, we examined effects of landscape composition (% habitats) and configuration (edge density) on arthropods in fields and their margins, pest control, pollination and yields. Configuration effects interacted with the proportions of crop and non-crop habitats, and species’ dietary, dispersal and overwintering traits led to contrasting responses to landscape variables. Overall, however, in landscapes with high edge density, 70% of pollinator and 44% of natural enemy species reached highest abundances and pollination and pest control improved 1.7- and 1.4-fold respectively. Arable-dominated landscapes with high edge densities achieved high yields. This suggests that enhancing edge density in European agroecosystems can promote functional biodiversity and yield-enhancing ecosystem services. © 2019 John Wiley & Sons Ltd/CNRS
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| 15. |
- Riggi, Laura, et al.
(författare)
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Insecticide resistance in pollen beetles over 7 years - a landscape approach
- 2016
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Ingår i: Pest Management Science. - : Wiley. - 1526-498X .- 1526-4998. ; 72, s. 780-786
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUNDIn spite of considerable interest in the impact of pesticides on pest populations, few attempts have been made to link resistance patterns of insect pests to land-use features across spatial and temporal scales. We hypothesise that pollen beetle pesticide resistance increases in areas with a high proportion of oilseed rape and with an even mixture of winter and spring oilseed rape owing to high pesticide selection pressure in such areas.RESULTSHere, we investigated 7 years of lambda-cyhalothrin (Karate((R))) resistance in field-collected pollen beetle adults from a total of 180 sampling points across ten regions in Sweden. We found a positive effect on pollen beetle pesticide resistance of proportion of oilseed rape and even spring-winter oilseed rape mixture. However, this was true only for the regional spatial scale. Significant land-use effects in the long-term models, with oilseed rape data averaged over a longer (4 years) period of time, suggested an effect of regional landscape history on current pest resistance.CONCLUSIONFor successful control of pollen beetle pesticide resistance, we suggest a long-term regional strategy for oilseed rape management. This land-use approach provides a framework for further investigations that integrate resistance management into landscape research. (c) 2015 Society of Chemical Industry
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| 16. |
- Riggi, Laura, et al.
(författare)
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Pollen beetle mortality is increased by ground-dwelling generalist predators but not landscape complexity
- 2017
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Ingår i: Agriculture, Ecosystems and Environment. - : Elsevier BV. - 0167-8809 .- 1873-2305. ; 250, s. 133-142
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Tidskriftsartikel (refereegranskat)abstract
- Biological control of crop pests by naturally occurring arthropods depends on the entire community of natural enemies, but generalist predators and parasitoids are rarely considered in the same study. Also, the level of biological control in the field is affected by both within-field and landscape scale management. A multi-taxa approach that integrates multiple scales of management is needed to understand drivers for pest mortality. We examined local (weed cover and soil characteristics) and landscape (proportions of semi-natural and oilseed rape habitat) effects on natural enemy communities and biological control of pollen beetles in 15 oilseed rape (OSR) fields in Sweden. We found that agricultural intensification at the local (low weed cover) and landscape scale (low proportion of semi-natural area) increased evenness of generalist predators, but had no effect on the densities of pests and their natural enemies. This suggests that the generalist predators in OSR are well adapted to crop lands, at least within the examined gradient. Increasing OSR in the landscape decreased parasitoid densities and increased pest density, indicating a potential loss of pest control services by specialist natural enemies in landscapes with a high proportion of OSR. Finally, pollen beetle mortality increased with ground dwelling generalist predator abundance and soil clay content. Parasitism rates did not affect pest mortality, which is interesting as parasitoids have been considered major control agents in OSR. The hypothesis that increasing semi-natural habitat in the landscape enhances natural enemy abundances and species richness in agricultural landscapes was not supported. Local measures targeting generalist predators appear as a reasonable strategy to maximize pollen beetle control.
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| 17. |
- Shellhorn, Nancy, et al.
(författare)
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Time will tell: resource continuity bolsters ecosystem services
- 2015
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Ingår i: Trends in ecology & evolution. - : Elsevier BV. - 0169-5347 .- 1872-8383. ; 30, s. 524-530
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Tidskriftsartikel (refereegranskat)abstract
- A common suggestion to support ecosystem services to agriculture provided by mobile organisms is to increase the amount of natural and seminatural habitat in the landscape. This might, however, be inefficient, and demands for agricultural products limit the feasibility of converting arable land into natural habitat. To develop more targeted means to promote ecosystem services, we need a solid understanding of the limitations to population growth for service-providing organisms. We propose a research agenda that identifies resource bottlenecks and interruptions over time to key beneficial organisms, emphasising their resulting population dynamics. Targeted measures that secure the continuity of resources throughout the life cycle of service-providing organisms are likely to effectively increase the stock, flow, and stability of ecosystem services.
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