Search

Global demand for vegetable oil is projected to expand to 28 Mt by 2028. Oilseed rape (OSR) is the predominant oilseed crop in Europe. Its nutritional value is determined by seed oil content and fatty acids (FAs) composition. Insect pollination increases seed oil content, however, its benefit on FAs composition remains unknown. In this study, we address this gap by investigating the variation of OSR seed oil content and FAs composition along a gradient of bee abundance in farmed OSR fields. We used a pollinator exclusion experiment to disentangle the contribution of pollination processes, i.e. wind, self and insect pollination. We show that bees improved OSR nutritional value by increasing amount of poly-unsaturated FAs and decreasing the amount saturated and trans-saturated FAs. In addition, oil content was higher in seeds with than without access to pollinators. Our study provides for the first time, to the best of our knowledge, evidence that insect pollination enhances the quality value of OSR oil by affecting FAs composition. Such effect implies potential negative consequences with any further decline of pollinator abundance. More investigations are also needed to better understand the mechanisms by which insect pollination affects FAs composition, and the way to enhance such mechanisms. [ABSTRACT FROM AUTHOR]

• Watermelon flowers attract diverse insect taxa but either honey bees or native bees are dominant in every region. • Honey bees and other bees are equally effective at pollen deposition on stigma. • Limited information located across major growing regions; majority of data is from North America. • Increasing bee density, encouraging wild taxa, and deploying land use practices will likely improve pollination. For most food crops the identity and efficiency of pollinators across key growing regions remains a significant knowledge gap that needs to be addressed before we can develop crop-specific approaches for pollination service delivery. Here, we conducted a systematic literature review and meta-analysis on watermelon (Citrullus lanatus (Thunb. Matsum. & Nakai)), a globally important fruit crop, to identify the floral visitors and their efficiency across different growing regions. We found that 265 insect species visit watermelon flowers (including 5 orders, 18 families and 75 genera) across 17 countries and 6 continents. Bees and flies were the most abundant flower visitors overall, but show distinct regional differences. Honey bees were the majority visitor in 53% of growing regions (range: 0 – 94%), whilst wild bee species were more abundant in 42% of regions (range: 3.4 – 100%). Honey bees and other bees were equally effective at depositing pollen on stigmas, but varied in effectiveness for fruit set and seed set. Pollination data from global studies appear to be limited for the largest-scale watermelon producers, namely: China, Turkey, and India, with the majority (56%) of data available from North America. This synthesis identified four key themes for improving pollination in watermelon: increasing honey bee densities on crops where local polices and environmental conditions are suitable; introducing other managed pollinators; identifying key wild pollinator taxa to encourage within crops; and improving local and landscape management practices to support pollinators. [ABSTRACT FROM AUTHOR]

An increasing number of farmland initiatives aim to aid biodiversity conservation through alternative farming practices such as nature-inclusive farming. However, these approaches frequently lead to trade-offs between biodiversity conservation and crop yield. For example, buckwheat (Fagopyrum esculentum) is a melliferous crop that flowers for a long period in the summer when nectar in agricultural areas is generally scarce, and buckwheat cultivation could therefore contribute to wild pollinator conservation. However, honeybees (Apis mellifera) are placed to ensure sufficient crop pollination, which potentially increases resource competition with wild pollinators in and around the crop. Here, we have studied this trade-off by surveying pollinators in and around 16 small-scale (∼1 ha) flowering buckwheat fields and we determined the contribution of pollinator density to crop yield in a nature-inclusive farming project. We found that the buckwheat pollinator community was diverse, albeit dominated by honeybees. We found no clear indications of resource competition between honeybees and wild pollinators within the buckwheat fields. Honeybee density in the surroundings was generally low, and increased minimally during honeybee-hive placement. While densities of honeybees decreased non-linearly over the day in buckwheat fields, they did not (temporarily) move into the surroundings of the field, suggesting limited competition for resources with wild pollinators. Crop yield was largely dependent on crop pollinator density, notably of honeybees, and to a lesser extent crop biomass (as a proxy for agricultural management). Our results show that buckwheat cultivation fits well within nature-inclusive farming if some simple precautionary measures are being taken, such as limiting the honeybee-hive densities and placing hives only during the main flowering period. The introduction of buckwheat cultivation into crop rotation could then contribute to fill an important nectar gap in the summer, which potentially boosts wild pollinator populations in the long term. [ABSTRACT FROM AUTHOR]

Pollination management for highbush blueberry crops (Vaccinium spp.) generally depends on beehives stocked at variable densities, with little consideration given to optimal pollination levels dictated by the mating system of the crop. This approach limits our capability to accurately forecast the consequences of animal pollination on crop productivity and can result in pollination shortfalls. Using experimental and observational data, we estimated optimal pollination thresholds for blueberry crops that maximize fruit diameter. We manipulated stigmatic pollen loads and used Bayesian models to evaluate the effects on fruit diameter. In this way, we were able to define thresholds for deficient, optimal and supraoptimal pollen deposition in blueberries. These thresholds were then evaluated under field conditions in blueberry farms, and used simulations to estimate the minimum number of honeybee visits required for optimal blueberry pollen deposition. A quadratic relationship described fruit diameter in response to stigmatic pollen load, with optimal pollen deposition peaking at 192 pollen tetrads and ranging between 112 and 274. Our simulations showed that a flower visitation rate guaranteeing, on average, six to seven honeybee visits per flower (i.e. flower visitation rate of 0.6 visits per 100 flowers h−1) would result in 60% of the plant flowers receiving optimum stigmatic pollen deposition. Higher numbers of honeybee visits increased the probability that blueberry stigmatic pollen loads were below the optimum and the probability that smaller berries were produced. We show that adverse pollination scenarios in blueberries can occur through different pathways, either because of a deficit or an excess of pollination that directly impacts the quality of the fruits produced. By identifying thresholds, we provide a pragmatic basis for adaptive management of honeybees based on average visitation rates that are most suitable for growers to manipulate. Our study provides new insights into the mechanisms behind pollination, fruit production, and the contribution of honeybee to blueberry crops. We highlight that systematic pollination management through flower visitation monitoring and clear optimal pollination targets can help prevent detrimental pollination scenarios. [Display omitted] • Pollination shortfall risk blueberry production through different pathways. • Optimal pollen deposition ranges between 112 and 274 pollen grains. • Reaching optimal pollination for highbush blueberry requires 0.6 honeybee floral visits per 100 flower h.−1 • Excess of honeybee visits result in reduced stigmatic pollen loads and production. • Pollination management based on target values can optimize highbush blueberry productivity. [ABSTRACT FROM AUTHOR]

The study by Barahona-Segovia et al. (2023) examines the influence of edge effect, landscape composition, and local characteristics on non-bee flower visitors in apple orchards. While their article improves our understanding of ecosystem dynamics in agricultural landscapes, it has important limitations regarding the importance of non-flower visitors as pollinators and their ability to compensate for declines in wild bee populations. The study does not address the distinction between flower visitors and true pollinators, relying on indirect measures such as contact with flower reproductive parts and visitation rate as proxies for pollinator effectiveness. Therefore, the authors fail to measure the basic definition of pollination: the act of transferring pollen grains from the anther to the stigma of a flower. Thus, the methodology used and the results of the study do not support the effectiveness of non-bees as pollinators compared to wild bees. The authors should have been cautions in extrapolating the conclusions of their study for orchard management strategies. Further studies with solid evidence are needed to quantify the contribution of non-bee pollinators to crop pollination and to allow a fair comparison between bees and non-bee visitors. • Barahona-Segovia et al. (2023) study the influence of edge effect and landscape composition on non-bee flower visitors in apple orchards. • The study lacks evidence that non-bee visitors can effectively keep the pollination delivered by wild bee populations. • Caution is necessary when interpreting the study's findings and applying them to crop ecosystem management. • Direct measures of pollinator performance, such as pollen deposition, should be included in future studies. [ABSTRACT FROM AUTHOR]

To mitigate the effects of habitat loss on bee conservation and crop pollination, farmers are encouraged to plant flowers along the edges of crop fields. However, it is unclear where and to what degree these flower plantings are effective. Recent studies suggest that flower plantings may be less effective if they are established in landscapes with either very low or very high amounts of non-crop habitat. Moreover, while field edge flower plantings often increase the abundance and richness of bees in field edges, it is unclear whether this improves crop pollination or bee nesting success, which could increase bee populations over time. In this study we examined how field edge flower plantings and the landscape context in which they are established affect wild bee conservation and crop pollination. Across two years we established flower plantings of 0.1–0.5 ha along the edges of 17 of 34 commercial cucumber fields arranged across a gradient of landscape complexity. We then measured wild bee abundance, richness, and crop pollination in and around cucumber fields with and without plantings and assessed the nesting success of stem-nesting bees. We found that both field edge flowers and landscape-scale non-crop habitat had independent, positive effects on bee abundance, richness, nesting, or crop pollination in one of the two years of the study, and that the effects of field edge flowers on bees and crop pollination were not influenced by the surrounding landscape. We also found that managing field edges in a way that maintains naturally-occurring flowers may matter as much or more than flower plantings for short-term increases in bee abundance and richness. However, certain species of planted flowers might be associated with improved bee nesting success, an outcome important for both bee conservation and sustained crop pollination. • Examined how flower plantings and landscape affect wild bees and crop pollination. • Local flowers and surrounding landscape had positive effects in 1 of 2 study years. • Effects of field edge flowers were not influenced by the surrounding landscape. • Managing field edges to maintain naturally occurring flowers is important. • Local flowers may improve success of stem-nesting bees. [ABSTRACT FROM AUTHOR]

The preservation of pollinator habitat on croplands in the form of hedgerows, wildflower strips, and natural and semi-natural areas can help maintain and enhance wild bee populations in agricultural landscapes. However, there have been few comparisons of the effectiveness of different types of field-margin pollinator habitat in maintaining bee diversity and pollination of the focal crops. We compared wild bee abundance, species richness and community composition between strawberry crops bordered by hedgerows, and those bordered by larger expanses of natural land (forests). Strawberry is an ideal crop in which to investigate pollinator export from field margins as the rows are covered with straw, which reduces habitat for ground-nesting bees within the crop; thus, most wild pollinators need to enter the crop from the margins. We sampled bees in six strawberry fields with hedgerow margins and six strawberry fields with forested margins of at least 200 m in length, using a paired design. We examined strawberry pollen deposition at regular intervals into the fields, and the magnitude of pollinator export from the field margins towards the centre of the crops. We found that bees as a group were no more species-rich or abundant in crops bordered by forests than in crops bordered by hedgerows, although large-bodied bees were more abundant in the former than the latter. Regardless of field-margin type, we found that small wild bee abundance declined significantly from the edge to the centre of the crop, but honey bee (Apis mellifera L.) and large-bodied bee abundance did not. Strawberry pollen deposition also did not decline with distance into the crop. Although previous work indicates that small wild bees are more effective (yield-increasing) pollinators of strawberry on a per-visit basis, their limited foraging ranges suggest they may only pollinate areas near the crop margins, given typical field sizes in our area. [ABSTRACT FROM AUTHOR]

• The pollination behaviour of bumble bees is different than that of honey bees. • Bumble bee richness and abundance improve the pollination behaviour of honey bees. • Bumble' bees pollination behaviour was not influenced by bee richness or abundance. Pollination service in agricultural crops increases significantly with pollinator diversity and wild pollinator abundance. Differences in the foraging behaviour of pollinating insects are one of the reasons why pollinator diversity and abundance enhances crop pollination. Here, we focused on the foraging behaviour of honey bees and bumble bees in sweet cherry orchards. In addition, we studied the influence of bee diversity and abundance on the foraging behaviour of honey bees and bumble bees. Honey bees were found to visit fewer flowers than bumble bees. Bumble bees also showed a higher probability of changing trees between rows than honey bees. Both visitation rate and probability of row changes of honey bees increased with bumble bee diversity and with bumble bee abundance. We also found that the probability of row changes of honey bees increased with increasing bumble bee abundance. These effects of bumble bee richness and abundance on the pollination behaviour of honey bees can improve the pollination performance of honey bees in crops that depend on cross pollination. Our results highlight the higher pollination performance of bumble bees and the facilitative effect of wild pollinators to crop pollination. [ABSTRACT FROM AUTHOR]

Abstract Insect pollination improves the yield and quality of many crops, yet there is increasing evidence of insufficient insect pollinators limiting crop production. Effective Integrated Crop Pollination (ICP) involves adaptable, targeted and cost-effective management of crop pollination and encourages the use of both wild and managed pollinators where appropriate. In this study we investigate how the addition of honeybee hives affects the community of insects visiting oilseed rape, and if hive number and location affect pollinator foraging and oilseed rape pollination in order to provide evidence for effective ICP. We found that introducing hives increased overall flower visitor numbers and altered the pollinator community, which became dominated by honeybees. Furthermore a greater number of hives did not increase bee numbers significantly but did result in honeybees foraging further into fields. The timing of surveys and proximity to the field edge influenced different pollinators in different ways and represents an example of spatial and temporal complementarity. For example dipteran flower visitor numbers declined away from the field edge whereas honeybees peaked at intermediate distances into the field. Furthermore, no significant effects of survey round on wild bees overall was observed but honeybee numbers were relatively lower during peak flowering and dipteran abundance was greater in later survey rounds. Thus combining diverse wild pollinators and managed species for crop pollination buffers spatial and temporal variation in flower visitation. However we found no effect of insect pollination on seed set or yield of oilseed rape in our trial, highlighting the critical need to understand crop demand for insect pollination before investments are made in managing pollination services. [ABSTRACT FROM AUTHOR]

Protective covers are commonly employed in agricultural systems to reduce the impacts of extreme weather events, pest species and to control the environmental conditions in which crop plants are grown. As protected cropping systems are expanding rapidly, there is an urgent need to better understand how variations in netting practices might impact pollination service delivery by wild and managed insects to pollinator dependent crops. We used southern highbush blueberry (Vaccinium corymbosum L. interspecific hybrid) crops to investigate (i) how variations in protected cropping structures (fully netted, partially netted and unnetted blocks) influence the amount and composition of pollen deposited on crop stigmas; (ii) to what extent blueberry floral abundance and plant richness in remnant vegetation influence pollen composition on crop stigmas; and (iii) the difference between stigmatic pollen load composition in the middle and at the edge of crop blocks. We collected data from 15 field blocks of 6 different cultivars distributed on 10 farms. We collected blueberry stigmas to analyse the pollen load and measured blueberry floral abundance and richness of flowering plant taxa in remnant vegetation every two weeks. Our results indicate that blueberry pollen abundance on stigmas was reduced by up to 81% under full netting and 36% by partial netting. On blueberry stigmas, we identified a total of 31 morphospecies of non-blueberry pollen from 20 plant families. There was no relationship between blueberry stigmatic pollen loads and blueberry floral abundance. Moreover, the composition of non-blueberry pollen on stigmas differed between blueberry blocks under different netting categories. However, there was no relationship between plant taxa present in the surrounding remnant vegetation of each block and the pollen load on the stigmas of each block. Combining all netting treatments, stigmas located at the edge of the blocks received a greater amount of both conspecific (5% more) and heterospecific (40% more) pollen grains than those within the middle of blocks. Pollen flow in fields is reduced under netting structures as well as in the middle of blocks. Reduced blueberry pollen flow under nets may be detrimental to fruit yield and quality for some varieties of pollinator dependent crops, particularly those that are self-incompatible. • Protective nets reduce deposition of conspecific and heterospecific pollen on blueberry stigmas. • Composition of heterospecific pollen on blueberry stigmas is not associated with surrounding vegetation. • Pollen loads on blueberry stigmas are not related to blueberry flower abundance. • Stigmas at the edge of the blocks receive more pollen grains compared to stigmas in the middle. [ABSTRACT FROM AUTHOR]

• The common bean flowers were visited by several insect orders, mainly Lepidoptera (butterflies). • Plants are self-compatible, exhibited a high reproductive efficiency and pollen limitation during one season. • Fruits resulted from spontaneous self-pollinations have higher morphometrics parameters and seed germination is also higher when compared to cross and natural pollination. The influence of animal pollination on the common bean (Phaseolus vulgaris L., Fabaceae) production is quite variable, but there is a tendency towards the predominance of strong self-fertility. Few studies tested for the influence of pollination on quality aspects of production and seed germination. In view of the global economic importance of the common bean, and the pollinator crisis that the planet is experiencing, the objective of this study was to investigate the influence of animal pollination in the amount and quality of fruits, seeds, and seed germination of the common bean, using four plantations of the 'mulatinho' variety in a region under semiarid climate of NE Brazil as a model. Our hypotheses are: 1) Flowers are visited mainly by bees; 2) The production of fruits, seeds and seed germination are favored by pollinators. Data were collected during the 2017 and 2018 plantings, when data on floral visitors were collected. Controlled crosses (spontaneous self-, cross- and natural pollinations) were performed and the number and morphometry of fruits, number, morphometry, and germination of seeds were compared between the experiments. Reproductive efficiency (RE) and pollen limitation index (PLI) were calculated. Number of formed fruits, measurements, weight, and germination resulting from spontaneous self-pollination showed higher values than those formed by natural and cross-pollination. In 2017, the RE was high (1.44) and the ILP was 0.14, indicating no pollen limitation. In 2018, RE was also high (1.8), but the ILP was 0.3, indicating pollen limitation. Overall, the frequency of visits on focal individuals was low. Conversely to what was expected, butterflies and moths were the most frequent floral visitors, although the flowers were also visited by bees, ants, flies beetles and spiders. None were considered pollinators because they did not touch the reproductive structures of the flower. The bee Xylocopa sp. was the only species capable of pollinating the flowers, as its size allows it to expose the reproductive parts present inside the keel when it lands on the flower to collect the floral resource. However, its frequency was very low, and it did not visit the focal plants. Apparently, low temperatures and high rainfall negatively interfered with pollination and, consequently, with the production. The common bean can be considered a relevant crop in the face of the current global pollinator crisis, as it does not depend on pollinators to produce food, the flowers are used by several pollinator groups and, additionally, it contributes to soil nitrogenating, reducing input costs for farmers. [ABSTRACT FROM AUTHOR]

Wild pollinators are a valuable natural resource for crops, as they often increase their production and quality. For this reason, there is currently a great interest in the development of management and conservation tools that help to maintain a wide variety of wild pollinators in agro-systems. To achieve this, it becomes a priority to study the diversity of wild pollinators in relevant crops as well as the local and landscape characteristics that benefit them. The almond tree ( Prunus dulcis ) is a crop of high economic interest, with a large dependence on pollinators due to the self-incompatibility of most of its varieties and, thus, it is very vulnerable to pollinator losses. By using field data and habitat characterization of 18 almond fields in Mallorca Island (Spain), we assessed how the abundance and diversity of pollinators varied with local and landscape characteristics (at 1 and 2 km buffer zones) of the fields, and how those affected almond production (fruit set). Almond trees were mostly pollinated by honeybees, but they were also visited by a large number of wild pollinators. The percentage of natural area in the 2 km buffer zones increased both pollinator-species richness and honeybee visits. At the field level, the flower community in the ground positively influenced almond production, both directly and indirectly by increasing the diversity of wild pollinators. Pollinator-species diversity directly increased fruit production but was negatively affected by honeybee abundance, which suggests that a high density of honeybees might result in negative effects on almond production through competition with wild pollinators. Management strategies to improve almond production might include favoring wild pollinators through the maintenance of natural habitats surrounding crop fields, and preserving the flowering herb community that occurs spontaneously in the groundcover of almond fields in Mediterranean areas. [ABSTRACT FROM AUTHOR]

As the Anthropocene advances, understanding the complex web of interactions between species has become a central theme in the maintenance of biodiversity, ecosystem functions, and agricultural systems. Plant-flower visitor networks yield insights into how natural vegetation supports crop pollination. Although crops themselves also support pollinators, the importance of spillover of flower-visiting pollinators from natural vegetation into croplands is increasingly appreciated. Natural vegetation not only provides forage and nesting sites, but can also support crop flower visitors when the crop is not flowering. We evaluated indirect effects between mango (the dominant tropical fruit crop globally) and wild plant species in neighbouring vegetation, and the factors determining these indirect effects, by constructing flower visitor networks. We constructed these networks for transects that included mango fields and neighbouring natural vegetation in north-eastern South Africa. Surveys were conducted before, during and after mango flowering, to allow evaluation of the importance of pollinator support when the crop was not in flower. Network analysis showed that potential indirect effects of other plant species on mango increased with flower abundance of those species, although this increase was less marked for species growing in natural vegetation. The cumulative (total, i.e. indirect effects summed) effect of natural vegetation on mango flower visitation was greater both during mango flowering and when it was not flowering. This is likely because of the greater plant diversity in natural systems, and because the combination of these species provided flowers over a protracted period. These positive indirect effects among plants flowering over extended periods of time have to date rarely been considered in crop pollination studies. Given the rapid expansion of high-intensity, high-yield monoculture plantings, such effects warrant further investigation. [ABSTRACT FROM AUTHOR]

Ecological intensification of agriculture implies managing ecological processes to improve performance of agricultural systems. However, impacts on relevant ecological functions such as insect pollination from other crop management factors are poorly explored. Pest insects and crop resources such as water availability can directly affect crop yields, but it is unknown if there are indirect effects through effects on insect pollination. With a factorial experiment, we examined how irrigation and control of pollen beetles affected crop attractiveness and pollinator visitation in an open-pollinated spring oilseed rape cultivar. We studied how irrigation and pest control modified the production of flowers and nectar in oilseed rape, and if this in turn affected the flower-visitation of honey bees and bumble bees. Pest control increased the number of oilseed rape flowers by 69%, and the amount of nectar per flower with 36%, but for the latter only in non-irrigated plots. Furthermore, we found higher pollinator densities in plots with reduced pollen beetle densities. Pest control also reduced the number of non-legitimate flower visits, suggesting higher pollination efficiency in plots with reduced pollen beetle densities. We show that crop management affects the value of mass-flowering crops as a resource for pollinating insects. Development of pest control tools that are harmless to pollinators could increase the value of flowering crops as food resources for pollinating insects. [ABSTRACT FROM AUTHOR]

Introduced plant species integrate into native trophic networks, often disrupting flower-visitation patterns. Although non-native invasive plants frequently occur in disturbed natural vegetation bordering crop fields, their impact on crop pollination has not been studied. We investigated whether an invasive plant ( Lantana camara ) influences flower visitation to mango ( Mangifera indica ), a pollinator-dependent crop, and whether the invasive supports mango pollinators when mango is not flowering. We surveyed insect flower-visitation in mango orchards bordering natural vegetation and within adjacent natural vegetation, with and without L. camara present, before, during and after mango flowering. We used these data to calculate the indirect effect of L. camara on mango through shared flower visitors before, during and after mango flowering, and the effects of the invasive on crop productivity. Lantana camara had a positive effect on mango flower visitation at low to medium mango flower density, but not at high mango flower densities. Although L. camara and mango shared flower visitor species, the frequency with which these flower visitor species visited the crop and the invasive differed markedly before, during and after mango flowering. Furthermore, the potential indirect effect of L. camara on mango via shared visitors was greatest when mango was flowering, but significantly lower before and after mango flowering, suggesting that the invasive is unimportant in the diet of mango flower visitors when the crop is not flowering. Contrary to findings in previous studies using native species in mango fields, there was a trend (not significant) for lower mango fruit production in fields with L. camara . This suggests that Lantana does not contribute to an increase in successful pollination of mango. Although our focal alien invasive plant species facilitated flower visitation of crops, it had no effect on mango production, and provided little support to mango flower visitor species that live longer than the crop’s flowering period. Given that L. camara is detrimental to grazing and was not associated with increased mango production, the removal of this invasive is advisable. [ABSTRACT FROM AUTHOR]

There is a growing consensus that the world is facing a pollination crisis. To mitigate crop pollination deficits, some management strategies include the massive introduction of managed bee species, yet quite often they are applied blindly, as information on crop pollination effectiveness for each single pollinator species of assemblages is usually not available. Therefore, the introduction on managed species is not always the best option to improve crop yields. Here, by using the highly pollinator-dependent alfalfa crop (Medicago sativa L.) as a case study, we propose the use of the effectiveness landscape framework to identify key crop pollinator species. According to this framework, in a mutualistic interaction, each species´ effectiveness is represented by the product of a quantitative component and a qualitative one, these being measures of the outcomes of this interaction. We applied this framework for two managed and four wild bee species that visit alfalfa in fields southwest of Buenos Aires province, Argentina. We dissected the quantity components of the pollinator effectiveness landscape by estimating two quantitative subcomponents: visitation rate and flower tripping rate. Also, we estimate pod set as a qualitative component without dissecting it in subcomponents. Our results showed that the contribution of both components and the resulting pollinator effectiveness varied among pollinator species, indicating a contrasting effectiveness of different bee species on alfalfa pollination. For example, pollinator effectiveness was higher for managed than for wild bees, as consequence of their very high visitation rate, however, wild bee flower tripping rate and pod set were as high as managed ones. In fact, wild bees were more effective in promoting flower tripping than one of the managed bees (A. mellifera). This approach allowed us to assess which effectiveness components and subcomponents make pollinator species more or less effective, thus providing valuable information to identify key species to be enhanced to help in closing yield gaps. We suggest that the application of the effectiveness landscape framework would be useful to develop strategies to improve crop pollination service in pollinator-dependent crop systems. • Identification of key crop pollinator species is essential. • Effectiveness landscape decomposes effectiveness into components and subcomponents. • Effectiveness landscape allows us to assess the effectiveness of each crop pollinator species. • This approach is useful for crop pollination management strategies. [ABSTRACT FROM AUTHOR]

Plant-pollinator interactions are ubiquitous in nature where both wild and domesticated pollinators interact with wild plant communities and entomophilous crops. Honeybees are important pollinators in many crop systems, but recent declines in honeybee stocks in Europe and the US have caused concern about the sustainability of crop systems solely depending on honeybees. In addition, several studies have shown that honeybees might negatively affect native pollinator populations, bumblebees in particular. Here we have studied flower visitation to two raspberry farms and surrounding wildflower communities in SE Norway. Bumblebees were excluded from the raspberry field by means of exploitative competition from honeybees ( > 97% of flower visits in the raspberry fields were conducted by honeybees). More than 55% of the visits recorded in wild plant communities surrounding the farms were conducted by bumblebees, showing that bumblebees were present in the system. Pollinator taxa were affected differently by temperature; honeybee visits showed a unimodal relationship with maximum flower visitation activity at a temperature of 24.1 °C, while flower visits by bumblebees showed a positive, linear relationship with temperature. The effect of temperature was much weaker for bumblebees than for honeybees (∼2.2% of the variation was explained by temperature, compared to ∼46% for honeybees). Farming practice affected flower visitation, as flowers within growing tunnels received fewer visits. However, the number of flower visits, also within the growing tunnels, was far above what other studies have shown to be sufficient for optimal pollination in raspberry. We conclude that the raspberry fields were sufficiently pollinated by honeybees but that the system should be considered vulnerable as it is solely dependent on this particular pollinator species. The honeybees were sensitive to ambient temperature suggesting that they might suffer more from future climate change than bumblebees. [ABSTRACT FROM AUTHOR]

Understanding the spatial-temporal variability in ecosystem services (ES) demand can help anticipate externalities of land use change. This study presents new operational approaches to quantify and map demand for three non-commodity ES on a global scale: animal pollination, wild medicinal plants and outdoor recreation. We show how the demand for these ES differs between beneficiaries and world regions. While the demand for animal pollination is accounted for via the consumption preferences for pollinator-dependent crop products, the demand for wild medicinal plants is quantified by the direct reliance on wild medicinal plants for basic healthcare needs. The demand for outdoor recreation is represented by the possibility and interest to participate in related activities. For animal pollination and outdoor recreation, demand is highest in industrial countries; demand for wild medicinal plants is highest in least developed countries, given their direct reliance on this ES for healthcare. Spatial demand-supply mismatches can cause trade-offs between ES in distant provisioning areas and can lead to unintended impacts on human well-being. The study reveals that quantifying and mapping spatial patterns of ES demand on a global scale requires clear conceptualization and operationalization of specific ES to select the most appropriate methods and arrive at meaningful results. [ABSTRACT FROM AUTHOR]

Managing the impacts of land use change on ecosystem services is essential to secure human wellbeing; but is a task often complicated by landscape-scale spatial dynamics. In this study, we focus on one type of spatial dynamic: multi-site interactions (MSI), which we define to occur when a change in the supply or use of an ecosystem service at one site affects that service at a second site. In search of empirical evidence of MSI, we reviewed 150 papers on one ecosystem service—nature-based recreation. We found many studies assessed impacts of land use change on this ecosystem service, but only 2% of studies quantified changes in its supply or use across multiple sites. Given this limited evidence in the literature, we propose a novel framework to describe the pathways through which MSI emerge and their likely consequences for ecosystem services across multiple sites. We illustrate the utility of this framework for understanding impacts on three other services: crop pollination, fuel wood production and flood mitigation. Obtaining empirical evidence of MSI is an important next step in ecosystem service science, which will help identify when interactions among sites emerge and how they can be best managed. [ABSTRACT FROM AUTHOR]

The contribution of wild pollination service to global agriculture is increasingly recognized. Still, biotic pollination demand is mainly covered by managed species, whereas implementing ecological intensification practices to promote wild pollination service remain less common. In this study, we evaluated (i) the effect of wild and managed pollinators and the richness of pollinator functional groups (RPFG) on production quality (i.e., fruit size) and quantity (i.e., crop yield), of two southern highbush blueberry (Vaccinium corymbosum) cultivars, and (ii) how wild pollinator service and crop production correlate with farm's land cover. We found that pollination service supply and the spatial context interact with the blueberry cultivar to determine yield and fruit size. The abundance of big-sized wild bees and hummingbirds positively affected fruit size and crop yield, but the relationship's significance was cultivar-dependent. In contrast, the increase in honeybees visitation rate was detrimental to the average fruit size of blueberries, but the effect was not generalizable between cultivars. The amount of forested area affected positively wild pollinator abundance and RPFG only in one cultivar, whereas grassland and hedgerow had adverse effects for pollinators in the other. Consistently, the relation between blueberry fruit size and the farm's land cover was subordinate to the cultivar. That is, despite all significant relations had the same sign between cultivars, their coefficients were statistically different. Our results support the idea that wild pollinators contribute to producing higher yields and larger berries in blueberry crops. Moreover, we found that the retention of natural forest at a 200 m radius within the farm may increase pollination service supply. However, the significance of every effect was contingent on the blueberry cultivar. This cultivar-dependent response points out that a robust assessment of pollinator benefits not only should include multiple production metrics, but also must incorporate within-crop variation, particularly in systems where growers use a mosaic of cultivars with different pollination requirements. • Wild pollination increases yield and berry size depending on the cultivar. • Honeybees can be detrimental to berry size depending on the cultivar. • Forrest's effects on pollinators and blueberry production varied with the cultivar. • Robust assessment of pollinator benefits should incorporate cultivar variability. [ABSTRACT FROM AUTHOR]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Although several studies have shown that the presence of bees results in increased crop yields, the mechanisms that determine pollination service across different spatial scales are still largely unknown. Here, we evaluated the influence of landscape structure over bee community composition and coffee ( Coffea arabica ) pollination. Our study was undertaken in one of the most important coffee-producing regions of Brazil, and comprised nine landscapes of sun coffee plantations surrounded by different amounts of Atlantic Forest remnants. Using floral exclusion experiments we evaluated fruit set in 15 coffee shrubs per landscape. We also sampled the bees visiting coffee flowers. Our analyses were made at two landscape scales, with 1 and 2 km radii, and one shrub scale, with 300 m radius around each coffee shrub. We collected 241 bee individuals and identified a total of 22 species. The honeybee Apis mellifera (Apini) was the most abundant flower visitor followed by Trigona spinipes (Meliponini). Native bee abundance, richness and diversity were positively affected by forest cover at the shrub scale. Honeybee abundance, on the other hand, was negatively affected by forest cover at the shrub scale. The presence of bees resulted in an increase in coffee fruit set of 28%. A. mellifera abundance positively affected fruit set across spatial scales, while the composition of the native bee community affected fruit set differently at the landscape scales than at the shrub scale. Our work shows that bee pollination services are affected by landscape structure at different spatial scales. These findings can be used in conservation and agricultural planning to maximize crop production while safeguarding biodiversity and the provision of pollination services. [ABSTRACT FROM AUTHOR]

The productivity of approximately 75% of crops worldwide depends to some extent on insect pollination. However, while global agriculture is becoming more dependent on pollinators, wild populations of pollinators are declining. For this reason, hives of Apis mellifera (honeybees), the most widely used pollinator, are commonly placed in the fields; in recent years, alternative managed pollinators (AMPs) such as Bombus spp. or Osmia spp. have also been used. Thus, for evidence-based pollination management, we need to know whether the pollination service provided by AMPs can replace, complement or synergistically interact with that provided by honeybees. We asked: Does crop productivity differ between fields with honeybees and those with AMPs? Does productivity increase by incorporating AMPs in addition to managed honeybees? Do the effects of managed honeybees and AMPs interact? We performed a meta-analysis based on 28 studies on 20 crops. We estimated effect sizes (ln(R)) for crop productivity (fruit/seed set, fruit/seed quality and yield) from 73 comparisons between honeybees and an AMP, and 21 comparisons between honeybees alone and honeybees plus an AMP. Overall, we found no evidence of difference in crop productivity between honeybees and AMPs when managed separately. However, the productivity of crops pollinated by honeybees together with AMPs was 22% ± 6 (SE) higher than that of crops pollinated only by honeybees. Moreover, we found a weak evidence of a positive effect of beehive density on crop productivity when an AMP was added, suggesting a synergistic interaction between honeybees and AMPs. We conclude that, on average, honeybee performance is similar to that of AMPs, and that increasing the number of managed pollinator species can improve crop productivity in the short-term, particularly in systems with impoverished pollinator faunas. More generally, this review confirms the positive effect of pollinator diversity on pollination service, suggesting this can be partly recreated using a suite of managed pollinators. • Effect of honeybees and alternative managed pollinators on crop productivity was assessed. • Honeybees did not differ from other AMPs in productivity, even in confined environments. • Including AMPs with honeybees improves crop productivity. • AMPs and honeybees together can have a synergistic effect on crop productivity. [ABSTRACT FROM AUTHOR]

Northern Thailand is orienting its agriculture towards intensive production systems at risk of being subjected to the current worldwide pollinator crisis. Bee-friendly pest management, improving native bee habitats within agro-forest ecosystems and fostering the husbandry of native bee species are three widely recognized strategies to conserve the local pollinating fauna. We attempted at eliciting farmers' valuation of these measures and that of their potential effect on local native bees, by conducting a choice experiment with 198 longan (Dimocarpus longan) farmers. The results of a mixed logit model indicate a significant heterogeneity in farmers' preferences, part of which was explained by the respondents' attitude towards native bees, among other idiosyncratic variables such as gender. We also determined a generally positive willingness to pay for the above mentioned conservation measures, which implemented together were valued at approx. €18.1 by the average household, all else equal. Additionally, avoiding a 50% native bee population decline was valued in average at €40.5 per household. These estimates stand in strong contrast with the comparatively high economic losses such a decline could potentially entail in terms of reduced longan production and the relatively low investment costs to implement a conservation strategy aimed at preventing such losses. [ABSTRACT FROM AUTHOR]

Solitary bees are receiving increasing attention as they are very effective crop pollinators. However, widespread implementation of pollination management with solitary bees is hampered by a lack of targeted and practical guidelines. Indeed, little evidence-based guidelines exist about the preferred type of nesting material, how to control nest-associated macroparasites and how to promote a healthy offspring with sufficient female bees. This study investigated whether different types of artificial nesting materials – paper straws and wooden grooved boards – are preferred by the European orchard bee (Osmia cornuta). In addition, we explored how the bee nesting success and infestation of macroparasites are influenced by type of nesting material, landscape complexity and timing throughout the active nesting period of O. cornuta. We found that O. cornuta preferred to nest in paper straws compared to wooden grooved boards. The number of produced brood cells and the offspring sex-ratio (i.e. the ratio of female:male bees) were higher in wooden grooved boards. Number of brood cells, successful cocoon development and the sex-ratio all decreased throughout the nest-construction period of the bees. The sex-ratio also increased with increasing landscape complexity. Paper straws had a reduced infestation rate of kleptoparasitic mites. In addition, the infestation rate of both kleptoparasitic mites and kleptoparasitic drosophilid flies increased with time throughout the bees' nest-construction period. These findings present relevant evidence to aid successful implementation of solitary bees for crop pollination. Utilization of paper straws, or similar materials, over wooden grooved boards and closing the nests near the end of the bees' active nest-construction period should be recommended practices. Implementation of these practices will reduce parasite infestation and enhance bee nesting success. Furthermore, conservation of semi-natural habitat or planting pollinator-friendly vegetation around fields is also advised to promote the proportion of female bees in the offspring. • O. cornuta prefers to nest in paper straws compared to wooden grooved boards. • Paper straws reduced the infestation rate of kleptoparasitic mites. • Bee nesting success decreased throughout the nest-construction period of the bees. • Infestation of mites and drosophilid flies increased through the nesting period. • The offspring's sex-ratio increased with increasing landscape complexity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Field beans are pollinated by a few important bumblebee species. [•] Oilseed rape is pollinated by a diverse insect community which varies spatially and temporally. [•] Managment to improve pollination service should be targeted at specific crops. [Copyright &y& Elsevier]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Highlights: [•] Trials using honeybees to pollinate Vicia faba were replicated in 17 fields. [•] Yield was greater (17%) and spatial variation was lower near hives. [•] Yield map data were consistent with observations of bee density and fruit per stem. [•] Economic analysis indicates that managed pollination is profitable for V. faba. [•] Other field crops could benefit from similar pollination management strategies. [ABSTRACT FROM AUTHOR]

Abstract: Pollination services are known to provide substantial benefits to human populations and agriculture in particular. Although many species are known to provide pollination services, honeybees (Apis mellifera) are often assumed to provide the majority of these services to agriculture. Using data from a range of secondary sources, this study assesses the importance of insect pollinated crops at regional and national scales and investigates the capacity of honeybees to provide optimal pollination services to UK agriculture. The findings indicate that insect pollinated crops have become increasingly important in UK crop agriculture and, as of 2007, accounted for 20% of UK cropland and 19% of total farmgate crop value. Analysis of honeybee hive numbers indicates that current UK populations are only capable of supplying 34% of pollination service demands even under favourable assumptions, falling from 70% in 1984. In spite of this decline, insect pollinated crop yields have risen by an average of 54% since 1984, casting doubt on long held beliefs that honeybees provide the majority of pollination services. Future land use and crop production patterns may further increase the role of pollination services to UK agriculture, highlighting the importance of measures aimed at maintaining both wild and managed species. [Copyright &y& Elsevier]

Abstract: Bumblebees have suffered declines as a result of reduction in habitat availability associated with agricultural intensification. Although several conservation strategies for bumblebees address forage availability, other aspects of bumblebee ecology are often ignored. Availability of sufficient nest sites is a key requirement of bumblebee populations and since nesting habitat is likely to have become reduced on intensively farmed land, lower nest site availability may contribute to bumblebee declines. The use of artificial domiciles for bumblebees has been proposed as a potentially useful tool for conservation and for improving pollination services for crops, providing a method of boosting nest site availability where it is otherwise limiting. Here, six different artificial domiciles for bumblebees are trialled in different habitats in southern England and central Scotland. Of these, only one domicile design at one particular site achieved reasonable uptake rates, whilst all other combinations of domicile and site achieved low success. Overall, only 23 of 736 domiciles deployed were occupied by bumblebees (3.1%). Based on current knowledge, attempts to use domiciles for conservation or research in the UK are likely to be ineffective. Commercially available domiciles for bumblebees performed poorly in these trials and the implications of these findings for manufacturers are discussed. [Copyright &y& Elsevier]

Non-bee insects have been identified as important crop pollinators globally. However, strategies to protect pollinators and enhance crop pollination usually focus on supporting bees. This study examined the effects of landscape structure, location within field, and floral resources on pollinators' visits on mass-flowering caraway (Carum carvi L.) in boreal farmland, and the effects of the visits on caraway yield. Pollinator visits on caraway flowers were monitored and caraway yield measured in 30 fields at landscapes ranging from field-dominated to forest-dominated landscapes. Hoverflies were the most abundant flower-visitors of caraway, followed by honeybees. Hoverflies and other flies made more flower visits on caraway than all bee species combined. Pollinator groups differed in their responses to landscape and local factors. Flies were most abundant near field edges and in landscapes with high forest cover. Non-syrphid flies and solitary bees responded positively to the cover of flowering herbs in the adjacent field margins. Flower visits by honeybees, instead, were positively related to the flowering crop cover in the study fields. Caraway seed yield increased with increasing number of flower visits by honeybees, hoverflies and all pollinators together. Pollinator exclusion reduced caraway fruit set (i.e. the number of fruits per flower) by 13% and seed yield by 40%. Our study is the first to report the high importance of flies to crop pollination in boreal farmland, where caraway is an important export crop. The results highlight the need of taking flies and their habitat requirements into account when developing strategies to enhance crop pollination. • Hoverflies were the most frequent flower-visitors on caraway, followed by honeybees. • Flies made more flower visits than all bee species combined. • Flies were abundant near field edges and in landscapes with high forest cover. • Honeybees responded positively to the flowering crop cover. • Flower visits by both honeybees and hoverflies increased caraway yield. [ABSTRACT FROM AUTHOR]

Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abundance and diversity are thought to be in decline, threatening sustainable food production. The Western honey bee (Apis mellifera) is amongst the best-monitored insects but the state of other managed pollinators is less well known. Here, we review the status and trends of all managed pollinators based on publicly accessible databases and the published literature. We found that, on a global scale, the number of managed A. mellifera colonies has increased by 85% since 1961, driven mainly by Asia. This contrasts with high reported colony overwinter mortality, especially in North America (average 26% since 2007) and Europe (average 16% since 2007). Increasing agricultural dependency on pollinators as well as threats associated with managing non-native pollinators have likely spurred interest in the management of alternative species for pollination, including bumble bees, stingless bees, solitary bees, and flies that have higher efficiency in pollinating specific crops. We identify 66 insect species that have been, or are considered to have the potential to be, managed for crop pollination, including seven bumble bee species and subspecies currently commercially produced mainly for the pollination of greenhouse-grown tomatoes and two species that are trap-nested in New Zealand. Other managed pollinators currently in use include eight solitary bee species (mainly for pollination services in orchards or alfalfa fields) and three fly species (mainly used in enclosures and for seed production). Additional species in each taxonomic category are under consideration for pollinator management. Examples include 15 stingless bee species that are able to buzz-pollinate, will fly in enclosures, and some of which have a history of management for honey production; their use for pollination is not yet established. To ensure sustainable, integrated pollination management in agricultural landscapes, the risks, as well as the benefits of novel managed pollinator species must be considered. We, therefore, urge the prioritization of biodiversity-friendly measures maintaining native pollinator species diversity to provide ecosystem resilience to future environmental changes. [Display omitted] • Diversity of managed pollinators has increased over time, totalling 66 species. • Native species and their traits might drive the trend in diversification. • Globally, the number of managed honey bee colonies has risen by 85% since 1961. • High colony mortality of Apis mellifera is reported, especially in North America. • Managed pollinators may negatively affect native, non-managed pollinators. [ABSTRACT FROM AUTHOR]

Abstract: Pollination provided by bees enhances the production of many crops. However, the contribution of wild bees remains unmeasured for many crops, and the effects of anthropogenic change on many bee species are unstudied. We experimentally investigated how pollination by wild bees affects tomato production in northern California. We found that wild bees substantially increase the production of field-grown tomato, a crop generally considered self-pollinating. Surveys of the bee community on 14 organic fields that varied in proximity to natural habitat showed that the primary bee visitors, Anthophora urbana Cresson and Bombus vosnesenskii Radoszkowski, were affected differently by land management practices. B. vosnesenskii was found primarily on farms proximate to natural habitats, but neither proximity to natural habitat nor tomato floral abundance, temperature, or year explained variation in the visitation rates of A. urbana. Natural habitat appears to increase B. vosnesenskii populations and should be preserved near farms. Additional research is needed to determine how to maintain A. urbana. Species-specific differences in dependency on natural habitats underscore the importance of considering the natural histories of individual bee species when projecting population trends of pollinators and designing management plans for pollination services. Thus, to maintain an entire bee community, multiple approaches, including maintaining natural habitat, should be implemented. [Copyright &y& Elsevier]

The importance of wild bees for crop pollination is well established, but less is known about which species contribute to service delivery to inform agricultural management, monitoring and conservation. Using sites in Great Britain as a case study, we use a novel qualitative approach combining ecological information and field survey data to establish a national list of crop pollinating bees for four economically important crops (apple, field bean, oilseed rape and strawberry). A traits data base was used to establish potential pollinators, and combined with field data to identify both dominant crop flower visiting bee species and other species that could be important crop pollinators, but which are not presently sampled in large numbers on crops flowers. Whilst we found evidence that a small number of common, generalist species make a disproportionate contribution to flower visits, many more species were identified as potential pollinators, including rare and specialist species. Furthermore, we found evidence of substantial variation in the bee communities of different crops. Establishing a national list of crop pollinators is important for practitioners and policy makers, allowing targeted management approaches for improved ecosystem services, conservation and species monitoring. Data can be used to make recommendations about how pollinator diversity could be promoted in agricultural landscapes. Our results suggest agri-environment schemes need to support a higher diversity of species than at present, notably of solitary bees. Management would also benefit from targeting specific species to enhance crop pollination services to particular crops. Whilst our study is focused upon Great Britain, our methodology can easily be applied to other countries, crops and groups of pollinating insects. • Bees provide critical ecosystem services, yet currently there are no lists of crop pollinators to advise management. • We outline a novel approach to identify bee species important for crop pollination at a national scale. • Whilst a small number of common species make the majority of flower visits, many more also contribute to pollination. • Our results show that management to support pollinators need to be targeted, and benefit a greater diversity of species. [ABSTRACT FROM AUTHOR]

• We assessed insect contribution to white and narrow-leaved lupin crop yield. • Protein crop yield increased with 3–11 % depending on crop species and variety. • Visitation rate of buff-tailed bumblebees increased protein yield up to 40 %. • Lupins do not produce nectar, so ample nectar should be provided in surroundings. • Increasing lupin cultivation may contribute to bringing back endangered bumblebees. Global biodiversity is declining under pressure of agricultural intensification and land-use change. Two-thirds of the agricultural lands is directly or indirectly devoted to the production of animal products. Replacing animal-based proteins by plant-based proteins can be an important step to a more sustainable agricultural system. Lupins (Lupinus sp.) are promising crop species due to a high protein content of up to 40 %, but crop yields are unstable in both quantity and quality. This might be due to a lack of effective pollinators, but the contribution of insect pollination to lupin crop yield is unknown. Here we studied for five varieties of two common lupin crop species (L. albus and L. angustifolius) which pollinators visit lupin flowers, whether this depends on nectar production, and what the contribution of insect pollination is to crop yield. We used a semi-experimental setup and placed bagged and open-pollinated plants in pots along an expected gradient of insect visitors and determined several yield parameters. We recorded 1355 pollinator visits of only eight bee species. None of the varieties tested produced nectar. Compared to bagged plants, protein yield increase of open-pollinated plants ranged from 3 to 11% depending on variety. Yield of open-pollinated plants was only consistently related to visitation of the large-bodied buff-tailed bumblebee (B. terrestris group; 59 % of all pollinators) with impact on seed set related yield parameters (number of seeds and pods) being generally larger than on seed filling related yield parameters (g/plant). Within the observed range, higher visitation rate of buff-tailed bumblebees increased protein yield of open-pollinated plants with 10–40 %. Visitation rates of the smaller common carder bee (B. pascuorum ; 33 % of all pollinators), or all pollinators combined, were not significantly related to protein crop yield. This could indicate that only relatively large species are effective lupin pollinators. Lupins are generally considered self-pollinating, and therefore growers do not actively manage for insect pollination. Our results show that insect pollination, and in particular buff-tailed bumblebees, can contribute substantially to the crop yield, which suggests that management aimed at enhancing effective pollinator species can help to make lupin crop cultivation more profitable. Amongst others, such management should make sure that ample nectar is available in the surroundings of lupin crops, as lupin does not produce nectar. [ABSTRACT FROM AUTHOR]

• We conducted a systematic review and meta-analysis of 54 studies. • Field-edge flower plantings consistently increased pollinator richness and abundance in field edges and became more effective as they matured. • The influence of field-edge plantings on crop pollination and yield was inconsistent. • Factors such as landscape context and crop type may influence when plantings are effective. • Defining how plantings impact pollinator population growth would help clarify how they impact on crop pollination and pollinator conservation. Planting flowers along crop field edges is an increasingly common management strategy for addressing pollinator declines and improving crop pollination. However, few reviews have been published summarizing the efficacy of this specific management practice and how it impacts ecosystem service delivery to crops. We conducted a systematic review (54 studies) and meta-analysis (4–29 studies, depending on the response) to determine whether such plantings 1) increase pollinator abundance or richness within field edges, 2) increase the abundance or richness of pollinators visiting crop flowers, or 3) improve crop yields. Our review and meta-analysis suggest that field-edge flower plantings are highly effective at increasing pollinator richness and abundance in field edges and that plantings become more effective as they mature. However, the influence of field-edge plantings on crop pollination and yield is inconsistent. Planting size and richness did not change these results. While this analysis shows that field-edge flower plantings consistently increase pollinator abundance and richness, there remain critical gaps in our knowledge of when and how plantings can improve ecosystem service provision and delivery. Determining if field-edge plantings affect pollinator population growth may clarify how plantings improve crop pollination, while further research on landscape context and crop type may define when this happens. [ABSTRACT FROM AUTHOR]

• Crop pollination service needs to assess the size of a honey bee colony. • The colony size can be approximated by the inter-frames covered with bees (IFB). • The relation between the IFB and the colony size is logarithmic. • The IFB provide a simple and robust indicator of colony size. • The IFB provide an indicator to support colony survival and crop pollination. Changes in agricultural practices have lead to pollination deficits in entomophilous crops, leading to a growing interest in supplementing farmlands with managed colonies of honey bee, Apis mellifera. However, the metrics of a colony as a pollination unit is controversial due to the wide range of adult population sizes encountered in a colony, especially in relation with the time of year and beekeeping management. Correctly measuring the number of adult honey bees per hive is critical for farmers to adjust the number of colonies they need to meet crop pollination demand. We tested a simple non-invasive method to estimate the adult worker population size of colonies based on common beekeeping handlings. This method consisted in counting the number of inter-frames covered with adult bees (called IFB thereafter) from above the hive body. Based on the monitoring of 181 colonies, we investigated the nature of the relation between IFB and the adult bee population size and its context-dependence to the meterological conditions and hive type. We then evaluated the possible improvement of the method with additional IFB counted in the supers and from below the hive body. Finally, we analysed the robustness of the method by comparing estimates obtained from colonies observed by experimented and naive observers. We revealed a clear-cut logarithmic relation between the IFB and the adult population size, covering the effects of meteorological conditions and hive type. The counting of IFB from above the hive body were particularly sensitive to meteorological conditions, unlike those counted from below the hive body. Moreover, the counting of additional IFB from the supers slightly improved the estimates of adult population size. Interestingly, no difference of estimate was detected between experimented and naive observers, suggesting applied simplicity of the method. The IFB counting method thus provides a simple, non-invasive and robust indicator of the adult population size of a managed honey bee colony. The counting of IFB from below the hive body should be recommend due to the sensitivity to meteorological conditions of the counting of IFB from above the hive body. Beyond crop pollination, we also highlighted application perspectives of this method as an indicator of survival probability. This method can therefore be viewed as a standard for routine field monitoring (i) to help farmers to estimate rigorously the number of colonies they need to meet the crop pollination demand and (ii) to help beekeepers assessing the mortality risk of their colonies. [ABSTRACT FROM AUTHOR]

• We use a model of biodiversity and crop yield in intensive agriculture landscapes. • Optimal landscape composition differs among ecosystem services and stakeholders. • Management should account for different crop types and stochasticity. • Social average scenarios may be a better option for food security and biodiversity. Efficient management of agricultural management should consider multiple services and stakeholders. Yet, it remains unclear how to guarantee ecosystem services for multiple stakeholders' demands, especially considering the observed biodiversity decline following reductions in semi-natural habitat (SNH), and global change. Here, we use an ecosystem service model of intensively-managed agricultural landscapes to derive the best landscape compositions for different stakeholders' demands, and how they vary with stochasticity and the degree of pollination dependence of crops. We analyse three groups of stakeholders assumed to value different ecosystem services most – individual farmers (crop yield per area), agricultural unions (landscape production) and conservationists (biodiversity). Additionally, we consider a social average scenario that aims at maximizing multifunctionality. Trade-offs among stakeholders' demands strongly depend on the degree of pollination dependence of crops, the strength of environmental and demographic stochasticity, and the relative amount of an ecosystem service demanded by each stakeholder. Intermediate amounts of SNH deliver relatively high levels of the three services (social average). Our analysis further suggests that the current levels of SNH protection lie below these intermediate amounts of SNH in intensively-managed agricultural landscapes. Given the worldwide trends in agriculture and global change, current policies should start to consider factors such as crop type and stochasticity, as they can strongly influence best landscape compositions for different stakeholders. Our results suggest ways of managing landscapes to reconcile several actors' demands and ensure for biodiversity conservation and food production. [ABSTRACT FROM AUTHOR]