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There is increasing evidence that farmers in many areas are achieving below maximum yields due to insufficient pollination. Practical and effective approaches are needed to maintain wild pollinator populations within agroecosystems so they can deliver critical pollination services that underpin crop production. We established nesting and wildflower habitat interventions in 24 UK apple orchards and measured effects on flower‐visiting insects and the pollination they provide, exploring how this was affected by landscape context. We quantified the extent of pollination deficits and assessed whether the management of wild pollinators can reduce deficits and deliver improved outcomes for growers over 3 years. Wildflower interventions increased solitary bee numbers visiting apple flowers by over 20%, but there was no effect of nesting interventions. Other pollinator groups were influenced by both local and landscape‐scale factors, with bumblebees and hoverflies responding to the relative proportion of semi‐natural habitat at larger spatial scales (1000 m), while honeybees and other flies responded at 500 m or less. By improving fruit number and quality, pollinators contributed more than £16 k per hectare. However, deficits (where maximum potential was not being reached due to a lack of pollination) were recorded and the extent of these varied across orchards, and from year to year, with a 22% deficit in output in the worst (equivalent to ~£14 k/ha) compared to less than 3% (equivalent to ~£2 k/ha) in the best year. Although no direct effect of our habitat interventions on deficits in gross output was observed, initial fruit set and seed set deficits were reduced by abundant bumblebees, and orchards with a greater abundance of solitary bees saw lower deficits in fruit size. The abundance of pollinators in apple orchards is influenced by different local and landscape factors that interact and vary between years. Consequently, pollination, and the extent of economic output deficits, also vary between orchards and years. We highlight how approaches, including establishing wildflower areas and optimizing the ratio of cropped and non‐cropped habitats can increase the abundance of key apple pollinators and improve outcomes for growers. [ABSTRACT FROM AUTHOR]

Keywords: dependency ratio; ecosystem services; exclusion experiment; field beans; insect pollinators; oilseed rape; TESSA; visitation frequency; colza; experimento de exclusión; frecuencia de visita; haba común; índice de dependencia; insectos polinizadores; servicios ambientales; ; ; ; ; ; ; (TESSA); EN dependency ratio ecosystem services exclusion experiment field beans insect pollinators oilseed rape TESSA visitation frequency colza experimento de exclusión frecuencia de visita haba común índice de dependencia insectos polinizadores servicios ambientales (TESSA) 1 13 13 08/01/22 20220801 NES 220801 INTRODUCTION The information resulting from ecosystem service assessments is useful to a wide range of stakeholders, decision makers, and nongovernmental organizations to highlight the importance of ecosystem services for humans and biodiversity (Neugarten et al., 2018). This includes the deduction of the estimated pollination value at 3 km, which is done to exclude the baseline pollination services provided by those pollinators that persist in the agricultural matrix independent of the pollination services provided by a natural or seminatural area (e.g., nature reserves) (method a2). [Extracted from the article]

Bumblebee pollination is crucial to the production of tomato in protected cultivation. Both tomato yield and flavor play important roles in attracting attentions from growers and consumers. Compared with yield, much less work has been conducted to investigate whether and how pollination methods affect tomato flavor. In this study, the effects of bumblebee pollination, vibrator treatment, and plant growth regulator (PGR) treatment on tomato yield and flavor were tested in Gobi Desert greenhouses. Compared with vibrator or PGR treatments, bumblebee pollinated tomato had higher and more stable fruit set, heavier fruit weight, and more seed. We also found that the seed quantity positively correlated with fruit weight in both bumblebee pollinated, and vibrator treated tomato, but not in PGR treated tomato. Besides enhancing yield, bumblebee pollination improved tomato flavor. Bumblebee pollinated tomato fruits contained more fructose and glucose, but less sucrose, citric acid, and malic acid. Furthermore, the volatile organic compounds of bumblebee pollinated tomato were distinctive with vibrator or PGR treated tomato, and more consumer liking related compounds were identified in bumblebee pollinated tomato. Our findings provide new insights into the contributions of bee pollinator towards improving crop yield and quality, emphasizing the importance of bumblebee for tomato pollination. [ABSTRACT FROM AUTHOR]

Keywords: agriculture; economic valuation; global value chain; globalisation; pollination services; trade EN agriculture economic valuation global value chain globalisation pollination services trade 773 785 13 06/10/22 20220601 NES 220601 INTRODUCTION Animal pollination is a key process in the reproduction of many nutritious food crops (Aizen et al., 2008; Bailes et al., 2015). *: Negative numbers indicate economic gains as a result of price rises gl Of the 41-46 countries that experience economic gains following pollinator losses in affected countries, many experience relatively large gains (totalling $2.2-12.4 billion) that substantially offset the net global losses. *: Negative numbers indicate economic losses as a result of price rises gl Although economic gains are relatively much smaller than the losses, a number of countries that produce large areas of high-value insect-pollinated crops experience economic gains in every scenario. The model was more sensitive to price elasticity than pollinator dependence ratio in two of the three case studies, as the price rise resulting from falling production under the high elasticity scenarios (LDHE, HDHE) compensates for a greater proportion of the losses, even under the high pollinator dependence scenario (HDHE). [Extracted from the article]

Wild bees provide a critical ecosystem service by pollinating globally important crops. Documented bee declines, notably in agricultural landscapes, therefore threaten future food security. Yet, evaluations of methods to inventory bees are rarely carried out in different crops or focus specifically upon crop pollinating species.We utilise standardised field datasets to elucidate differences in the capacity of transect walks, observation plots and pan traps to sample wild bee pollinator communities in four contrasting crops. Our results indicate that individual survey methods detect different components of crop pollinator communities, with guild and body size potentially important causal factors behind these differences.Transects detected half or less of the total potential pollinator community in three of our four study crops. Whilst transects were the most efficient method for sampling bumblebees, they often missed smaller solitary species, which were most efficiently sampled by yellow pan traps.Crop type is likely an important determinant of the most suitable survey methods to sample bee pollinator communities. Whilst transects alone are sufficient in crops pollinated predominantly by bumblebees, pan traps, and potentially observation plots, may be an important addition in some crops where smaller solitary bee species are potentially important pollinators.Our results indicate that the most efficient methods to sample bee species in agricultural landscapes are dependent upon crop type and pollinator community composition. We use our findings to make a set of recommendations on the inventorying and monitoring of bee pollinator crop communities that can inform regional and national monitoring programmes. [ABSTRACT FROM AUTHOR]

Pollinators face multiple pressures and there is evidence of populations in decline. As demand for insect‐pollinated crops increases, crop production is threatened by shortfalls in pollination services. Understanding the extent of current yield deficits due to pollination and identifying opportunities to protect or improve crop yield and quality through pollination management is therefore of international importance. To explore the extent of "pollination deficits," where maximum yield is not being achieved due to insufficient pollination, we used an extensive dataset on a globally important crop, apples. We quantified how these deficits vary between orchards and countries and we compared "pollinator dependence" across different apple varieties. We found evidence of pollination deficits and, in some cases, risks of overpollination were even apparent for which fruit quality could be reduced by too much pollination. In almost all regions studied we found some orchards performing significantly better than others in terms of avoiding a pollination deficit and crop yield shortfalls due to suboptimal pollination. This represents an opportunity to improve production through better pollinator and crop management. Our findings also demonstrated that pollinator dependence varies considerably between apple varieties in terms of fruit number and fruit quality. We propose that assessments of pollination service and deficits in crops can be used to quantify supply and demand for pollinators and help to target local management to address deficits although crop variety has a strong influence on the role of pollinators. [ABSTRACT FROM AUTHOR]

Pollinators experience large spatiotemporal fluctuations in resource availability when mass‐flowering crops are rotated with resource‐poor cereal crops. Yet, few studies have considered the effect this has on pollinator population stability, nor how this might be mitigated to maintain consistent crop pollination services.We assess the potential of boundary features (standard narrow 1 m grassy margins, hedgerows and wide 4 m agri‐environment margins) to support and stabilise pollinator populations and pollination service in agricultural landscapes under crop rotation. Assuming a 6‐year rotation, we use a process‐based pollinator model to predict yearly pollinator population size and in‐crop visitation rates to oilseed rape and field bean across 117 study landscapes in England with varying amounts of boundary features. We model both ground‐nesting bumblebees and solitary bees and compare the predictions including and excluding boundary features from the landscapes.Ground‐nesting bumblebee populations, whose longer‐lifetime colonies benefit from continuity of resources, were larger and more stable (relative to the no‐features scenario) in landscapes with more boundary features. Ground‐nesting solitary bee populations were also larger but not significantly more stable, except with the introduction of wide permanent agri‐environment margins, due to their shorter lifetimes and shorter foraging/dispersal ranges.Crop visitation by ground‐nesting bumblebees was greater and more stable in landscapes with more boundary features, partly due to increased colony growth prior to crop flowering. Time averaged crop visitation by ground‐nesting solitary bees was slightly lower, due to females dividing their foraging time between boundary features and the crop. However, despite this, the minimum pollination service delivered was higher, due to the more stable delivery.Synthesis and applications. Field boundary features have an important role in stabilising pollinator populations and pollination service in rotational systems, although maintenance of larger semi‐natural habitat patches may be more effective for stabilising less mobile solitary bee populations. We recommend using combinations of boundary features, accounting for pollinator range when spacing features/rotating crops, and synchronising boundary feature management with crop rotation to maximise their stabilising benefits. [ABSTRACT FROM AUTHOR]

Evidence of declines in wild and managed pollinators and pollination services is increasingly being documented around the world. This has driven the development of a wide range of practical management and policy responses which were reviewed in the Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services (IPBES) global assessment of 'Pollinators, Pollination and Food Production'. We take 38 responses from this report as a basis to explore the importance of scale for the effective delivery of an intervention's benefit to pollinators. We considered five scale categories: Spatial, the spatial scale at which the response is most effective; Temporal, the time scale over which the response is most effective; Actors, the number of actors needed for most effectively implementing a response; Social, the sphere of influence or motivation that determines an effective response; and, Sector, the sector(s) of society which should be involved to increase effectiveness. Each scale category was split into multiple levels and we scored each in terms of how important they were for determining the effectiveness of a given response option. Using our combined scores, we aim to explore general trends and raise awareness around the main issues relating to the importance of scale, with illustrated examples from the literature. We show how scales have impacted on the effectiveness of interventions and provide recommendations on how to improve scale matching when planning a response action. While the relative importance of scales and levels for effectiveness was heterogeneous across response options, there were some general patterns. Interventions were only effective when targeted over the right spatial scales over a sufficient period of time and involved all relevant social and sectoral groups and actors. [ABSTRACT FROM AUTHOR]

Resilient pollination services depend on sufficient abundance of pollinating insects over time. Currently, however, most knowledge about the status and trends of pollinators is based on changes in pollinator species richness and distribution only.Systematic, long‐term monitoring of pollinators is urgently needed to provide baseline information on their status, to identify the drivers of declines and to inform suitable response measures.Power analysis was used to determine the number of sites required to detect a 30% change in pollinator populations over 10 years. We then evaluated the full economic costs of implementing four national monitoring schemes in the UK: (a) professional pollinator monitoring, (b) professional pollination service monitoring, (c) volunteer collected pan traps and (d) volunteer focal floral observations. These costs were compared to (a) the costs of implementing separate, expert‐designed research and monitoring networks and (b) the economic benefits of pollination services threatened by pollinator loss.Estimated scheme costs ranged from £6,159/year for a 75‐site volunteer focal flower observation scheme to £2.7 M/year for an 800‐site professional pollination service monitoring network. The estimated research costs saved using the site network as research infrastructure range from £1.46–4.17 M/year. The economic value of UK crop yield lost following a 30% decline in pollinators was estimated at ~£188 M/year.Synthesis and applications. We evaluated the full costs of running pollinator monitoring schemes against the economic benefits to research and society they provide. The annual costs of monitoring are <0.02% of the economic value of pollination services that would be lost after a 30% decline in pollination services. Furthermore, by providing high‐quality scientific data, monitoring schemes would save at least £1.5 on data collection per £1 spent. Our findings demonstrate that long‐term systematic monitoring can be a cost‐effective tool for both answering key research questions and setting action points for policymakers. Careful consideration must be given to scheme design, the logistics of national‐scale implementation and resulting data quality when selecting the most appropriate combination of surveyors, methods and site networks to deliver a successful scheme. [ABSTRACT FROM AUTHOR]

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Rising demand for food production poses a major threat to biodiversity by placing competing pressures on land. Diversified farming systems are one widely promoted nature-based solution to this challenge, which aim to integrate biodiversity-based ecosystem services into agricultural production. The underlying theory behind this approach is that diverse communities enhance ecosystem service provision, although the evidence to support this theory is often inconsistent for reasons that are not always clear. Here we investigate the contribution of pollinators to ecosystem function in a model example of a diversified farming system, silvoarable agroforestry comprising apple trees intercropped within arable fields. We assess pollinator species richness, species diversity, and functional trait diversity, between agroforestry fields and paired monoculture arable controls, and within agroforestry fields at set distances from tree rows, to quantify their potential contributions to pollination service. Species richness and diversity, and functional richness and dispersion, of wild bees were found to be significantly higher in agroforestry systems, despite weak effects on mean trait values. No significant effects were found for hoverflies. Supplemental bee species found in agroforestry systems were shown to increase functional diversity primarily by enhancing niche complementarity, effectively filling in gaps in niche space for traits, which could be partly attributed to a higher abundance and diversity of floral resources in the associated understorey. Nationally rarer bee species also contributed substantially to functional richness but not consistently to functional dispersion, suggesting that while they provide a unique functional role, their contributions to ecosystem services remain limited by low local abundances. These mechanistic insights reveal how the relationship between biodiversity and ecosystem functioning can be influenced by farm management practices through their effect on the spatial and temporal availability of habitat resources. • Bees had higher functional diversity in agroforestry than adjacent arable fields. • Additional bee species show niche complementarity for multiple traits. • Niche complementary was often found when there was no effect on mean trait response. • Higher functional dispersion in bee traits was linked to diversity in floral traits. • Low local abundance of rarer species limited contribution to ecosystem function. [ABSTRACT FROM AUTHOR]

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]

Agri-environment schemes are programmes where landholders enter into voluntary agreements (typically with governments) to manage agricultural land for environmental protection and nature conservation objectives. Previous work at local scale has shown that these features can provide additional floral and nesting resources to support wild pollinators, which may indirectly increase floral visitation to nearby crops. However, the effect of entire schemes on this important ecosystem service has never previously been studied at national scale. Focusing on four wild pollinator guilds (ground-nesting bumblebees, tree-nesting bumblebees, ground-nesting solitary bees, and cavity-nesting solitary bees), we used a state-of-the-art, process-based spatial model to examine the relationship between participation in agri-environment schemes across England during 2016 and the predicted abundances of these guilds and their visitation rates to four pollinator dependent crops (oilseed rape, field beans, orchard fruit and strawberries). Our modelling predicts that significant increases in national populations of ground-nesting bumblebees and ground-nesting solitary bees have occurred in response to the schemes. Lack of significant population increases for other guilds likely reflects specialist nesting resource requirements not well-catered for in schemes. We do not predict statistically significant increases in visitation to pollinator-dependent crops at national level as a result of scheme interventions but do predict some localised areas of significant increase in bumblebee visitation to crops flowering in late spring. Lack of any significant change in visitation to crops which flower outside this season is likely due to a combination of low provision of nesting resource relative to floral resource by scheme interventions and low overall participation in more intensively farmed landscapes. We recommend future schemes place greater importance on nesting resource provision alongside floral resource provision, better cater for the needs of specialised species and promote more contiguous patches of semi-natural habitat to better support solitary bee visitation. • We have modelled the impact of England's agri-environment schemes on wild bees. • We predict only ground-nesting bee populations have increased nationally. • Current schemes produce no significant increase in national crop pollination service. • We find only localised pollination service increases to late-spring flowering crops. • Insufficient provision of nesting resources may be a key limitation in scheme design. [ABSTRACT FROM AUTHOR]