Landscape composition modifies pollinator densities,foraging behavior and yield formation in faba beans

Wildlife-friendly management practices promote pollinators and pollination services in agricultural landscapes. Wild bee densities are driven by landscape composition, as they benefit from an increased availability of nesting and foraging resources at landscape scale. However, effects of landscape composition on bee foraging decisions and consequences for crop pollination have rarely been studied. We investigated, how landscape composition affects bee densities and foraging behavior in faba bean (Vicia faba L.) fields and how this impacts faba bean yield. We recorded densities and nectar robbing behavior of honeybees, long- tongued and short-tongued bumblebees in faba bean fields in eleven landscapes with varying landscape composition (e.g. land cover of oilseed rape, faba bean and semi-natural habitats). Moreover, we assessed yield components of faba beans via pollinator exclusion experiments. Increasing covers of faba bean and semi-natural habitats positively influenced bumblebee densities, while high oilseed rape covers negatively affected short-tongued bumblebee densities in bean fields. Increased faba bean covers enhanced the proportion of nectar-robbing short-tongued bumblebees. The number of beans per pod was increased by insect pollination, while the number of pods was decreased; these effects however depended on variety. Landscape composition interacted with bee densities in shaping yield components in V. faba. Our study emphasizes the importance of considering landscape management to maximize crop yields, as shown for the case of faba beans. The composition of agricultural landscape can modulate bee densities in crop fields, bees foraging behavior and pollination services.     

Plant evolution can mediate negative effects from honey bees on wild pollinators

1. Pollinators are introduced to agroecosystems to provide pollination services. Introductions of managed pollinators often promote ecosystem services, but it remains largely unknown whether they also affect evolutionary mutualisms between wild pollinators and plants.
2. Here, we developed a model to assess effects of managed honey bees on mutualisms between plants and wild pollinators. Our model tracked how interactions among wild pollinators and honey bees affected pollinator and plant populations.
3. We show that when managed honey bees have a competitive advantage over wild pollinators, or a greater carrying capacity, the honey bees displace the wild pollinator. This leads to reduced plant density because plants benefit less by visits from honey bees than wild pollinators that coevolved with the plants.
4. As wild pollinators are displaced, plants evolve by increasing investment in traits that are attractive for honey bees but not wild pollinators. This evolutionary switch promotes wild pollinator displacement. However, higher mutualism investment costs by the plant to the honey bee can promote pollinator coexistence.
5. Our results show plant evolution can promote displacement of wild pollinators by managed honey bees, while limited plant evolution may lead to pollinator coexistence. More broadly, effects of honey bees on wild pollinators in agroecosystems, and effects on ecosystem services, may depend on the capacity of plant populations to evolve.

     

Bird and insect pollinators differ in specialization and potential pollination services along disturbance and resource gradients

Combined studies of the communities and interaction networks of bird and insect pollinators are rare, especially along environmental gradients. Here, we determined how disturbance by fire and variation in sugar resources shape pollinator communities and interactions between plants and their pollinating insects and birds. We recorded insect and bird visits to 21 Protea species across 21 study sites and for 2 years in Fynbos ecosystems in the Western Cape, South Africa. We recorded morphological traits of all pollinator species (41 insect and nine bird species). For each site, we obtained estimates of the time since the last fire (range: 2–25 calendar years) and the Protea nectar sugar amount per hectare (range: 74–62 000 g/ha). We tested how post-fire age and sugar amount influence the total interaction frequency, species richness and functional diversity of pollinator communities, as well as pollinator specialization (the effective number of plant partners) and potential pollination services (pollination service index) of insects and birds. We found little variation in the total interaction frequency, species richness and functional diversity of insect and bird pollinator communities, but insect species richness increased with post-fire age. Pollinator specialization and potential pollination services of insects and birds varied differently along the environmental gradients. Bird pollinators visited fewer Protea species at sites with high sugar amount, while there was no such trend for insects. Potential pollination services of insect pollinators to Protea species decreased with increasing post-fire age and resource amounts, whereas potential pollination services of birds remained constant along the environmental gradients. Despite little changes in pollinator communities, our analyses reveal that insect and bird pollinators differ in their specialization on Protea species and show distinct responses to disturbance and resource gradients. Our comparative study of bird and insect pollinators demonstrates that birds may be able to provide more stable pollination services than insects.     

Spatio‐temporal patterns in pollination of deceptive Aristolochia rotunda L. (Aristolochiaceae)

• Pollination success of highly specialised flowers is susceptible to fluctuations of the pollinator fauna. Mediterranean Aristolochia rotunda has deceptive trap flowers exhibiting a highly specialised pollination system. The sole pollinators are kleptoparasitic flies in search of food. This study investigates these pollinators on a spatio‐temporal scale and the impact of weather conditions on their availability. Two potential strategies of the plants to cope with pollinator limitation, i.e. autonomous selfing and an increased floral life span, were tested.
• A total of 6156 flowers were investigated for entrapped pollinators in 10 Croatian populations. Availability of the main pollinator was correlated to meteorological data. Artificial pollination experiments were conducted and the floral life span was recorded in two populations according to pollinator availability.
• Trachysiphonella ruficeps (Chloropidae) was identified as dominant pollinator, along with less abundant species of Chloropidae, Ceratopogonidae and Milichiidae. Pollinator compositions varied among populations. Weather conditions 15–30 days before pollination had a significant effect on availability of the main pollinator. Flowers were not autonomously selfing, and the floral life span exhibited considerable plasticity depending on pollinator availability.
• A. rotunda flowers rely on insect pollen vectors. Plants are specialised on a guild of kleptoparasitic flies, rather than on a single species. Pollinator variability may result in differing selection pressures among populations. The availability/abundance of pollinators depends on weather conditions during their larval development. Flowers show a prolonged trapping flower stage that likely increases outcrossing success during periods of pollinator limitation.

     

Pollination efficiency of wild bees and hoverflies provided to oilseed rape

• 1 Declining numbers in honeybees and various wild bee species pose a threat to global pollination services. The identification and quantification of the pollination service provided by different taxa within the pollinator guild is a prerequisite for the successful establishment of nature conservation and crop management regimes.
• 2 Wild bees and hoverflies are considered to be valuable pollinators in agricultural and natural systems. Although some information on pollination efficiency of individual pollinator species is available, comparative studies of both taxa at different densities are rare. In the present study, the efficiency of the solitary mason bee Osmia rufa and two hoverfly species (Eristalis tenax and Episyrphus balteatus) as pollinators of oilseed rape Brassica napus was examined in a standardized caged plant breeding regime. Honeybee Apis mellifera colonies were used as a reference pollinator taxon.
• 3 Yield parameters responded differently to pollinator density and identity. Fruit set and number of seeds per pod increased with increasing pollinator density, although these were stronger in the mason bee than the hoverfly treatment. Weight per 1000 seeds did not respond to any pollinator treatment, indicating that seed quality was not affected. Oilseed rape yield in the highest tested densities of both pollinator taxa resulted in yield values close to the efficiency of small honeybee colonies.
• 4 Hoverflies required approximately five‐fold densities of the red mason bees to reach a similar fruit set and yield. Thus, mason bees are more efficient in plant breeding and managed pollination systems. Both natural pollinator taxa, however, are of potential value in open and closed crop production systems.

     

The impact of an insecticide on insect flower visitation and pollination in an agricultural landscape

• 1 Pesticides are considered a threat to pollinators but little is known about the potential impacts of their widespread use on pollinators. Less still is known about the impacts on pollination, comprising the ecosystem service that pollinators provide to wildflowers and crops.
• 2 The present study measured flower visitation and pollination in an agricultural landscape, by placing potted flowering plants (Petunia sp.) in vine fields sprayed with a highly toxic insecticide (fenitrothion). During two sampling rounds, insect visitors to the petunias were observed and measures of pollination were recorded by counting and weighing seeds.
• 3 In the earlier sampling round, a lower species richness of insect visitors was observed in fields that had received an early application of insecticide. No negative impacts were found from later applications. The results obtained suggest a greater potential harm to insect pollinators and flower visitation as a result of insecticide application early in the season.
• 4 No reduction in pollination was found in fields that received an early insecticide application. Pollination was greater with two insecticide applications between sampling rounds rather than one application.
• 5 In the present study system, insecticide application had a negative effect on pollinators but a possible positive effect on pollination services. In some cases, it may be that actions for conserving biodiversity will not benefit pollination services to all plants.

     

Pollinator specialization increases with a decrease in a mass‐flowering plant in networks inferred from DNA metabarcoding

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The least effective pollinator principle: specialized morphology despite generalized ecology

• The large body of work on the adaptation of plants to pollinators is still somewhat incomplete because most studies focus on one‐to‐one interactions. How will adaptation proceed in a multi‐pollinator environment? According to Stebbins' Most Effective Pollinator Principle, ‘the characteristics of the flower will be moulded by those pollinators that visit it most frequently and effectively.’
• To test this hypothesis, we studied the pollination biology of Pelargonium incrassatum (Geraniaceae) in the Namaqualand Region of Southern Africa. This species has a long floral tube and we expected its most important pollinator to have a long proboscis.
• Contrary to expectations, the most important pollinator was a short proboscid fly (a new species of Prosoeca), while Prosoeca peringueyi, which had a proboscis that matched the floral tube length, was a rare visitor. Consistent with the high degree of trait mismatching, we did not detect selection on tube length at most sites.
• The paradox of mismatching traits can be resolved by considering the strength of the trade‐off involved. Adaptation to the rare species can apparently occur without incurring the cost of reduced pollination by the abundant species. Generally, species may often evolve specialized morphology if they do not incur the cost of ecological specialization.

     

Evolutionary disruption in the pollination system of Vanilla (Orchidaceae)

• Pollination of the pantropical Vanilla has been linked to melittophily and food deception.
• Here we investigated the role of flower traits on the reproduction of Neotropical Vanilla. We also studied the evolution of pollination systems in order to understand the origin of production of flower resources and the diversification of pollinators in this orchid genus. Our study was founded on data of adaptations in flower morphology, production of resources, scent release, pollinators and breeding systems of Vanilla and presenting new data on reproductive biology of V. palmarum. Data on reproductive biology of Vanilla were mapped onto a phylogeny to address our queries on the evolution of pollination systems in this genus.
• Vanilla palmarum shows a mixed mating system, with its facultative autogamous flowers being pollinated by hummingbirds. Its yellow flowers are scentless and produces nectar. Mapping of the pollination system onto trees resulted in one origin for bird pollination and at least two origins for autogamy in Vanilla. Nectar secretion has a single origin in the Neotropical thick-leafed lineage.
• Bird pollination of Vanilla is shown for the first time. The origin of ornithophily within a bee-pollinated clade is supported by flower morphology. Floral transitions to ornithophily have been favoured by the occupation of a distinct niche from that of the other thick-leafed Vanilla species. Despite its specialized pollination, V. palmarum is autogamous. A mixed mating system can promote reproductive assurance in the case of a decline in pollinator populations, or in areas where pollinator services are irregular or absent.

     

Relative effectiveness of insects versus hummingbirds as pollinators of Rubiaceae plants across elevation in Dominica,Caribbean

• Most angiosperms rely on animal pollination for reproduction, but the dependence on specific pollinator groups varies greatly between species and localities. Notably, such dependence may be influenced by both floral traits and environmental conditions. Despite its importance, their joint contribution has rarely been studied at the assemblage level.
• At two elevations on the Caribbean island of Dominica, we measured the floral traits and the relative contributions of insects versus hummingbirds as pollinators of plants in the Rubiaceae family. Pollinator importance was measured as visitation rate (VR) and single visit pollen deposition (SVD), which were combined to assess overall pollinator effectiveness (PE).
• In the wet and cool Dominican highland, we found that hummingbirds were relatively more frequent and effective pollinators than insects, whereas insects and hummingbirds were equally frequent and effective pollinators at the warmer and less rainy midelevation. Furthermore, floral traits correlated independently of environment with the relative importance of pollinators, hummingbirds being more important in plant species having flowers with long and wide corollas producing higher volumes of dilute nectar.
• Our findings show that both environmental conditions and floral traits influence whether insects or hummingbirds are the most important pollinators of plants in the Rubiaceae family, highlighting the complexity of plant–pollinator systems.

     

Pollinator‐independent orchid attracts biotic pollinators due the production of lipoidal substances

• Flowering plants often depend on the attraction of biotic pollinators for sexual reproduction. Consequently, the emergence and maintenance of selected floral attributes related to pollinator attraction and rewarding are driven by pollinator pressure.
• In this paper we explore the effect of pollinators, rainfall, temperature and air humidity on the reproduction of a Brazilian terrestrial orchid, Cranichis candida based on data of phenology, flower resources, olfactory and visual attraction cues, pollinators and breeding system.
• The flowers of C. candida are strongly protandrous and pollinated by workers of the social native bee Tetragonisca angustula. The bees collect labellar lipoidal substances (wax scales), which are transported to the nest. The lipoidal substance is composed of sterols, hydrocarbons and terpenes. The last presumably protects the bees and their nests against pathogens and other arthropods. C. candida sets fruits through biotic self‐ and cross‐pollination, and spontaneously due the action of raindrops on flowers.
• Our results indicate that in C. candida, although rain‐mediated spontaneous self‐pollination happens, fructification mediated by biotic pollinations also occurs, which may result in fruit set by cross‐pollination. A mixed pollination system must result in higher genetic variability when compared to species whose fruits are produced entirely by self‐pollination. On the other hand, autogamy is a form of reproductive assurance, and has commonly evolved where pollination services are rare or absent.

     

Potential negative effects of exotic honey bees on the diversity of native pollinators and yield of highland coffee plantations

• 1 The honey bee Apis mellifera is native to Eurasia and Africa, although it is commonly introduced into crop fields of different parts of the world because of the assumption that it improves yield. This bee is, however, a poor pollinator of several crops compared with native insects. Indeed, honey bees can displace native pollinators and reduce their diversity. The present study evaluated the potential impacts of A. mellifera on the diversity of native pollinators of highland coffee (Coffea arabica) and its putative consequences for coffee production at the state of Veracruz, Mexico.
• 2 The abundance of A. mellifera and diversity of native pollinators were assessed during blooming at 12 shade coffee plantations and pollination experiments were conducted to determine the impacts of pollinators on coffee fruit production. Regression analyses were used to assess whether the abundance of honey bees was related to native pollinator diversity, and whether fruit production was influenced by both the diversity of pollinators and the abundance of A. mellifera.
• 3 Native pollinator diversity decreased as the number of honey bees increased. Furthermore, although coffee fruit production was positively related to the diversity of native pollinators, an increasing abundance of A. mellifera was correlated with a decrease in fruit production.
• 4 Highland shade coffee plantations are considered as reservoirs of the Mexican insect fauna. Thus, native pollinator diversity could be better preserved if beekeepers reduced the number of managed hives that they brought into plantations. This may also help to increase coffee yield by decreasing the putative negative effects of A. mellifera on native pollinators.

     

Relative contributions to seed production by floral visitors of slickspot peppergrass, Lepidium papilliferum (Brassicaceae)

Assessing the relative contributions to seed production made by different types of floral visitors is fundamental to understanding the evolution of floral morphology and the influence that particular pollinator taxa have on plant fitness and reproduction. This 3-year study examined the pollinator activity and the seed production in three populations of Lepidium papilliferum, a threatened mustard endemic to sagebrush-steppe habitat in southwest Idaho. Relative amounts of time visitor taxa spent foraging on flowers, visitation rates (number of flowers visited per unit time during a foraging bout), and pollination effectiveness (fruit set per single visit to a virgin flower) were recorded for each of 12 insect taxa that visited L. papilliferum flowers. Relative contributions to seed production were calculated as the product of relative interaction frequencies (the relative number of flowers visited by each taxon—the “quantity” component of pollination) and pollination effectiveness (fruit set per single visit to a virgin flower—the “quality” component of pollination). Despite the superiority of some insect taxa in terms of pollination effectiveness, estimates of relative pollinator contributions to seed production were influenced primarily by an insect taxon’s interaction frequency with flowers. Pollinator assemblages varied widely both spatially and temporally, which suggest that L. papilliferum is not under strong selective pressure to shift from its generalist pollination strategy toward greater specialization. For this threatened plant, reliance on a diverse assemblage of insect pollinators may serve as an important buffer against disruption in reproductive success caused by fluctuations in population sizes of individual pollinator taxa.     

Seasonal complementary in pollinators of soft-fruit crops

Understanding the relative contributions of wild and managed pollinators, and the functional contributions made by a diverse pollinator community, is essential to the maintenance of yields in the 75% of our crops that benefit from insect pollination. We describe a field study and pollinator exclusion experiments conducted on two soft-fruit crops in a system with both wild and managed pollinators. We test whether fruit quality and quantity is limited by pollination, and whether different pollinating insects respond differently to varying weather conditions. Both strawberries and raspberries produced fewer marketable fruits when insects were excluded, demonstrating dependence on insect pollinators. Raspberries had a short flowering season which coincided with peak abundance of bees, and attracted many bees per flower. In contrast, strawberries had a much longer flowering season and appeared to be much less attractive to pollinators, so that ensuring adequate pollination is likely to be more challenging. The proportion of high-quality strawberries was positively related to pollinator abundance, suggesting that yield was limited by inadequate pollination on some farms. The relative abundance of different pollinator taxa visiting strawberries changed markedly through the season, demonstrating seasonal complementarity. Insect visitors responded differently to changing weather conditions suggesting that diversity can reduce the risk of pollination service shortfalls. For example, flies visited the crop flowers in poor weather and at the end of the flowering season when other pollinators were scarce, and so may provide a unique functional contribution. Understanding how differences between pollinator groups can enhance pollination services to crops strengthens the case for multiple species management. We provide evidence for the link between increased diversity and function in real crop systems, highlighting the risks of replacing all pollinators with managed alternatives.     

Insect pest damage increases faba bean (Vicia faba) yield components but only in the absence of insect pollination

Identifying and quantifying crop stressors interactions in agroecosystems is necessary to guide sustainable crop management strategies. Over the last 50 years, faba bean cropping area has been declining, partly due to yield instabilities associated with uneven insect pollination and herbivory. Yet, the effect of interactions between pollinators and a key pest, the broad bean beetle Bruchus rufimanus (florivorous and seed predating herbivore) on faba bean yield has not been investigated. Using a factorial cage experiment in the field, we investigated how interactions between two hypothesized stressors, lack of insect pollination by bumblebees and herbivory by the broad bean beetle, affect faba bean yield. Lack of bumblebee pollination reduced bean weight per plant by 15%. Effects of the broad bean beetle differed between the individual plant and the plant‐stand level (i.e., when averaging individual plant level responses at the cage level), likely due to high variation in the level of herbivory among individual plants. At the individual plant level, herbivory increased several yield components but only in the absence of pollinators, possibly due to plant overcompensation and/or pollination by the broad bean beetle. At the plant‐stand level, we found no effect of the broad bean beetle on yield. However, there was a tendency for heavier individual bean weight with bumblebee pollination, but only in the absence of broad bean beetle herbivory, possibly due to a negative effect of the broad bean beetle on the proportion of legitimate flower visits by bumblebees. This is the first experimental evidence of interactive effects between bumblebees and the broad bean beetle on faba bean yield. Our preliminary findings of negative and indirect associations between the broad bean beetle and individual bean weight call for a better acknowledgment of these interactions in the field in order to understand drivers of crop yield variability in faba bean.     

Bees provide pollination service to Campsis radicans (Bignoniaceae), a primarily ornithophilous trumpet flowering vine

1. Pollination syndromes refer to stereotyped floral characteristics (flower colour, shape, etc.) that are associated with a functional group of pollinators (bee, bird, etc.).
2. The trumpet creeper Campsis radicans, endemic to the southeast and mid‐west United States, has been assigned to the hummingbird‐pollination syndrome, due mainly to its red, trumpet‐shaped flowers.
3. Previous studies demonstrated that the ruby‐throated hummingbird Archilochus colubris is C. radicans' primary pollinator, but anecdotal data suggest various bee species may provide pollination service when hummingbirds are absent.
4. This study characterised C. radicans nectar volume and concentration by time of day. Nectar volume was suitable for hummingbirds, but concentration was higher than typical hummingbird‐pollinated plants (～20% w/w); at ～30% w/w, it approached the concentration expected in bee‐pollinated plants (～50% w/w). We also found substantial amounts of nectar at night.
5. Two C. radicans populations received virtually no hummingbird visits, but the number of bees were markedly higher than in the populations previously described. Interestingly, there were no night‐time visitors despite the large quantity of nocturnal nectar.
6. Based on previously published pollen delivery per visit by various species, this study estimated that cumulative deposition by bees routinely reached pollen deposition thresholds for setting fruit in C. radicans. They are, unequivocally, the predominant pollinators in these populations, thus providing pollination service in the absence of hummingbirds.
7. These results highlight C. radicans as a food source for native bees and add to the understanding of how floral phenotypes can facilitate pollination by disparate functional groups.

     

Pollination syndromes in a specialised plant‐pollinator interaction: does floral morphology predict pollinators in Calceolaria?

Pollination syndromes are defined as suites of floral traits evolved in response to selection imposed by a particular group of pollinators (e.g., butterflies, hummingbirds, bats). Although numerous studies demonstrated their occurrence in plants pollinated by radically different pollinators, it is less known whether it is possible to identify them within species pollinated by one functional pollinator group. In such a framework, we expect floral traits to evolve also in response to pollinator subgroups (e.g., species, genera) within that unique functional group. On this, specialised pollination systems represent appropriate case studies to test such expectations. Calceolaria is a highly diversified plant genus pollinated by oil‐collecting bees in genera Centris and Chalepogenus. Variation in floral traits in Calceolaria has recently been suggested to reflect adaptations to pollinator types. However, to date no study has explicitly tested that observation. In this paper, we quantitatively test that hypothesis by evaluating the presence of pollination syndromes within the specialised pollination system formed by several Calceolaria and their insect pollinators. To do so, we use multivariate approaches and explore the structural matching between the morphology of 10 Calceolaria taxa and that of their principal pollinators. Our results identify morphological matching between floral traits related to access to the reward and insect traits involved in oil collection, confirming the presence of pollinator syndromes in Calceolaria. From a general perspective, our findings indicate that the pollination syndrome concept can be also extended to the intra‐pollinator group level.     

Flower specialisation: the occluded corolla of snapdragons (Antirrhinum) exhibits two pollinator niches of large long‐tongued bees

• Flower specialisation of angiosperms includes the occluded corollas of snapdragons (Antirrhinum and some relatives), which have been postulated to be one of the most efficient structures to physical limit access to pollinators. The Iberian Peninsula harbours the highest number of species (18 Iberian of the 20 species of Antirrhinum) that potentially share similar pollinator fauna.
• Crossing experiments with 18 Iberian species from this study and literature revealed a general pattern of self‐incompatibility (SI) – failure in this SI system has been also observed in a few plants – which indicates the need for pollinator agents in Antirrhinum pollination.
• Field surveys in natural conditions (304 h) found flower visitation (>85%) almost exclusively by 11 species of bee (Anthophora fulvitarsis, Anthophora plumipes, Anthidium sticticum, Apis mellifera, Bombus hortorum, Bombus pascuorum, Bombus ruderatus, Bombus terrestris, Chalicodoma lefebvrei, Chalicodoma pyrenaica and Xylocopa violacea). This result covering the majority of Antirrhinum species suggests that large bees of the two long‐tongued bee families (Megachilidae, Apidae) are the major pollinators of Antirrhinum.
• A bipartite modularity analysis revealed two pollinator systems of long‐tongued bees: (i) the long‐studied system of bumblebees (Bombus spp.) associated with nine primarily northern species of Antirrhinum; and (ii) a newly proposed pollinator system involving other large bees associated with seven species primarily distributed in southern Mediterranean areas.

     

Valuing insect pollination services with cost of replacement

Value estimates of ecosystem goods and services are useful to justify the allocation of resources towards conservation, but inconclusive estimates risk unsustainable resource allocations. Here we present replacement costs as a more accurate value estimate of insect pollination as an ecosystem service, although this method could also be applied to other services. The importance of insect pollination to agriculture is unequivocal. However, whether this service is largely provided by wild pollinators (genuine ecosystem service) or managed pollinators (commercial service), and which of these requires immediate action amidst reports of pollinator decline, remains contested. If crop pollination is used to argue for biodiversity conservation, clear distinction should be made between values of managed- and wild pollination services. Current methods either under-estimate or over-estimate the pollination service value, and make use of criticised general insect and managed pollinator dependence factors. We apply the theoretical concept of ascribing a value to a service by calculating the cost to replace it, as a novel way of valuing wild and managed pollination services. Adjusted insect and managed pollinator dependence factors were used to estimate the cost of replacing insect- and managed pollination services for the Western Cape deciduous fruit industry of South Africa. Using pollen dusting and hand pollination as suitable replacements, we value pollination services significantly higher than current market prices for commercial pollination, although lower than traditional proportional estimates. The complexity associated with inclusive value estimation of pollination services required several defendable assumptions, but made estimates more inclusive than previous attempts. Consequently this study provides the basis for continued improvement in context specific pollination service value estimates.     

Can floral field margins improve pollination and seed production in coriander Coriandrum sativum L. (Apiaceae)?

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