访花昆虫多样性研究进展

芍药是我国重要的一类观赏和药用花卉，在油用方面的价值也越来越重要。本研究对当前主要的一类油用芍药资源——杭白芍的传粉特征和繁育系统进行了相关研究。结果表明，油用芍药存在一定程度的自交，但其授粉需要昆虫的辅助，以异交为主，属兼性自交的植物；但是存在自交衰退的现象。本研究可为油用芍药的生产及育种实践提供重要的理论支持。

紫丹参为云南省地方习用药材，本文对紫丹参的开花物候、花部特征、繁育系统及传粉方式进行初步研究。结果表明，紫丹参有长达5个月的花期，单花花期可持续30~50 d；花粉–胚珠比(P/O)为6509.67，杂交指数(OCI值)为4或5，繁育系统为自交亲和但需要传粉者完成传粉的兼性异交型，不存在无融合生殖现象。

在实地考察的基础上，编制河南省嵩县低等短角亚目名录。报道了河南双翅目1新记录科，臭虻科(Coenomyiidae)；1新记录属，臭虻属(Coenomyia)；以及1新记录种，黄斑臭虻(Coenomyia maculata Yang & Nagatomi, 1994)。凭证标本存放于中国农业大学昆虫学系。截至目前，嵩县记载的低等短角亚目昆虫共有7科37属70种。

有机管理模式下，采取保护农田边界植物与人工建设生态花带、施用沼肥进行生态化管理、病虫草害生态防控等措施，提高了农田非作物生境植物物种多样性和地上有益生物多样性，土壤线虫多样性结构得到优化。常规管理模式下，筛选出6种功能植物：矢车菊、紫花苜蓿、油菜、汤阴北艾、硫华菊、春黄菊，创建出一种小麦玉米农田天敌植物支持系统：紫花苜蓿 + 油菜 + 矢车菊天敌植物支持系统，建成了一种瓢虫和食蚜蝇周年栖息环境与迁移路径。

Electrical transmission rights-of-way are ubiquitous and critical infrastructure across the landscape. Active vegetation management of these rights-of-way, a necessity to deliver electricity more safely, maintains these landscape features as stages of early successional habitat, a rarity in many regions, making these areas viable movement corridors for many taxa. The goals of this study were to (i) evaluate the effects of different electrical transmission landscape management practices on flowering plant and flower-visiting insect diversity parameters and (ii) generate conservation management inferences for these landscapes. In this study we tested the impact of three vegetation management levels across 18 electrical transmission sites. We evaluated the effects of treatment on bloom abundance and species richness as well as flower-visiting insect abundance and family richness. We identified 76541 flowers/inflorescences across 456 transects, including 188 species in 56 plant families. Additionally, we obtained data on 11361 flower-visitoring insects representing 33 families from 2376 pan trap sets. High vegetation management favored the reduction of coarse woody debris in the sites and harbored the highest level of abundance and richness of both floral resources and flower-visiting insects. We discuss that we can align social and ecological values of rights-of-way, ensuring their sustainability by applying regular and targeted integrated vegetation management. Thus, we can use rights-of-way landscapes not only as an effective management strategy for the delivery of essential human services, but also to provide conservation benefits for wild pollinators.

Loss in the availability of early successional habitat is a threat to pollinator populations. Given that powerline rights-of-way (ROW) must be managed to maintain early successional habitat, preventing vegetation from interfering with electrical lines, they have the potential to provide conservation benefits for wild pollinators. Moreover, it is possible to provide conservation benefits with no additional cost to land managers. We surveyed flower-visiting insects over two years in different vegetation management treatments in a long-term research ROW to determine which best promoted pollinator abundance and species richness. We found that the ROW had stabilized in an early successional state soon after its establishment and that this early successional state could be maintained with low levels of periodic maintenance. We collected a high diversity of flower-visiting insects (126 bee species and 179 non-bee morphospecies) in six ROW plots. Higher levels of herbicide application had a negative effect on bee species richness, but low levels of herbicide application were compatible with a high abundance and species richness of flower-visiting insects, including several rare species. Moreover, this effect was seen only in the bee community, and not in non-bee flower-visiting insects. Our results suggest further research into the conservation value of ROW for pollinators is warranted. We demonstrate that there is substantial potential for pollinator conservation in ROW, compatible with low-cost vegetation management.

Gardening for pollinators and other flower-visiting insects, where ornamental landscaping plants are added to provide habitats and foraging resources, may provide substantial benefits to declining insect populations. However, plant recommendations often lack empirical grounding or are limited geographically. Here, we created a pollinator garden, replicated across two sites, that contained 25 ornamental landscape plants that were either native or non-native to mid-Atlantic states and perennial or annual. Our objective was to determine the plants that would bring insect abundance and diversity to gardens. We surveyed the number and taxonomy of insects visiting the plants for two summers. We found a significant effect of plant species on both the abundance and diversity of flower-visiting insects. Insects were 42 times more abundant on our most visited plant (black-eyed Susan, Rudbeckia fulgida) versus our least visited plant (petunia, Petunia sp.). There was more than one diversity point difference in the Shannon index between the plant with the most (purple coneflower, Echinacea purpurea) and least (verbena, Verbena bonariensis) diverse visitors. Across our plants, honey bee (Apis mellifera) abundance positively correlated with other insect pollinators, although not specifically with wild bee abundance. Native perennials outperformed non-native perennials and non-native annuals in insect abundance, and both non-native and native perennials attracted more diversity than non-native annuals. Across plants, diversity scores quadratically related to insect abundance, where the highest diversity was seen on the plants with medium abundance. Lastly, we present the weighted sums of all insect visitors per plant, which will allow future gardeners to make informed landscaping decisions. Overall, we have shown that gardening schemes could benefit from a data-driven approach to better support abundant and diverse insect populations within ornamental landscape gardens.

摘要: 为了解燕山地区访花昆虫的群落结构及与其生境类型、干扰程度

Despite the important role that flower-visiting insects play in agricultural production, none of the previous studies of coffee pollinators in Colombia have incorporated functional diversity into their analysis. Therefore, this study aimed to quantify the abundance, richness, and functional diversity of insects that visit flowers in coffee crops. Twenty-eight plots were selected among five sites in the north, center, and south of Colombia. In each plot, coffee flower insect visitors were collected and recorded on 90 trees at eight-minute intervals per tree, at three different times over three days. All sampling was carried out during two flowering events per year, over three years, resulting in a total of 1240 h of observations. Subsequently, the insects were taxonomically identified, and the number of individuals and species, as well as the diversity of the order q, were estimated. Functional diversity was also characterized in the bee community. The results: (a) 23,735 individuals belonging to 566 species were recorded; of them, 90 were bees, with the native species being the most abundant during 10:30 and 13:00 h; (b) bees formed five functional groups, with corbiculate and long-tongued non-corbiculate bees being the most abundant and occupying the largest regions of functional space; (c) potential pollinators in coffee crops are <i>Apis mellifera</i>, <i>Nannotrigona gaboi</i>, <i>Tetragonisca angustula</i>, <i>Geotrigona</i> cf. <i>tellurica</i>, and <i>Partamona</i> cf. <i>peckolti</i>. Coffee crops host a wide diversity of flower visitors, especially bees, which could be beneficial for productivity and contribute to the maintenance of plant species that accompany coffee cultivation.

Abstract Insects are declining in abundance and diversity, but their population trends remain uncertain as insects are difficult to monitor. Manual methods require substantial time investment in trapping and subsequent species identification. Camera trapping can alleviate some of the manual fieldwork, but the large quantities of image data are challenging to analyse. By embedding the image analyses into the recording process using computer vision techniques, it is possible to focus efforts on the most ecologically relevant image data. Here, we present an intelligent camera system, capable of detecting, tracking, and identifying individual insects in situ . We constructed the system from commercial off‐the‐shelf components and used deep learning open source software to perform species detection and classification. We present the Insect Classification and Tracking algorithm (ICT) that performs real‐time classification and tracking at 0.33 frames per second. The system can upload summary data on the identity and movement track of insects to a server via the internet on a daily basis. We tested our system during the summer 2020 and detected 2994 insect tracks across 98 days. We achieved an average precision of 89% for correctly classified insect tracks of eight different species. This result was based on 504 manually verified tracks observed in videos during 10 days with varying insect activities. Using the track data, we could estimate the mean residence time for individual flower visiting insects within the field of view of the camera, and we were able to show a substantial variation in residence time among insect taxa. For honeybees, which were most abundant, residence time also varied through the season in relation to the plant species in bloom. Our proposed automated system showed promising results in non‐destructive and real‐time monitoring of insects and provides novel information about phenology, abundance, foraging behaviour, and movement ecology of flower visiting insects.

Sunflowers and marigolds hold cultural and commercial significance while serving as important nectar sources for insects and contributing to ecosystem services. This study examined flower-visiting insect abundance, diversity and distribution in sunflower and marigold gardens at Rajshahi University Campus, Bangladesh. In sunflower gardens, we identified six orders, eight families, and twelve species of flower-visiting insects. Marigold gardens comprised six orders, eleven families, and fourteen species of insects. Hymenoptera (57.89%) and Diptera (45.71%) were the most abundant insect orders in sunflower and marigold, respectively. Apidae and Syrphidae were the predominant families in both gardens, with a combined share of 71.93% and 57.14% of the counted insects, respectively. The most dominant species was A. dorsata and E. quinquestriatus in sunflower and marigold garden, respectively. Notably, three species of flower-visiting insects were recorded as the most common visitors both in sunflower (A. dorsata, A. cerana, and Eristalis sp.) and marigold (A. dorsata, Eristalis sp., and E. quinquestriatus) gardens according to their abundance. Shannon's diversity index indicated medium biodiversity in both gardens (2.09 and 2.42), attributed to certain species' abundance. Additionally, both gardens exhibited high species richness (Menhinick index, 1.59 and 1.67) and similar individual distributions (Pielou's index, 0.84 and 0.92).

A field experiment was conducted at the Research farm of Department of Entomology, CCS Haryana Agricultural University (CCSHAU) Hisar, Haryana to determine the diversity and abundance of insect pollinators on two varieties of sesame HT-1 and HT-2 during 2017 and 2018. A total of 34 insect species belonging to 18 families from four orders were observed. Of these Apis dorsata (4.76 bees/ m²/ 5 min; 26.92% of total flower visitors) followed by A. mellifera (2.34 bees/ m²/ 5 min), M. lanata (2.23 bees/ m²/ 5 min) and A. florea (1.32 bees/ m²/ 5 min) were predominant. Peak activity of the insect visitors was observed at 1000-1200 hr of the day.

A study was conducted to determine the insect pollinators visiting apple flowers. In studies, Apple flowers attracted insects from five orders, including Hymenoptera, Diptera, Lepidoptera, Coleoptera and Thysanoptera. Of all the orders, insects belonging to order Hymenoptera were most abundant. They included honey bee Apis mellifera, Apiscerana, bumble bees Bombus sp. Anthophoride Xylocopafenestrata, X. aestuans X. pubescens, X. valga, Halictidae Halictus spp. Nomia spp. Lasiogllosum spp. Ceratina spp. Melissodes spp., Colletidae Colleteseous, vespidaeVespa orientalis, V. Cincta V. Mandarinia, Polistes hebraeus, megachilidae Osmia spp. Andrenidae Andrenaflaviceps, Formicide Camponotuscompressus. Honeybees were the most abundant of all flower visitors and made up more than 48% of the total.

Reported insect declines have dramatically increased the global demand for standardized insect monitoring data. Image-based monitoring can generate such data cost-efficiently and non-invasively. However, extracting ecological data from images is more challenging for insects than for vertebrates because of their small size and great diversity. Deep learning facilitates fast and accurate insect detection and identification, but the lack of training data for coveted deep learning models is a major obstacle for their application. We present a large annotated image dataset of functionally important insect taxa. The primary dataset consists of 29,960 annotated insects representing nine taxa including bees, hoverflies, butterflies and beetles across more than two million images recorded with ten time-lapse cameras mounted over flowers during the summer of 2019. The insect image dataset was extracted using an iterative approach: First, a preliminary detection model identified candidate insects. Second, candidate insects were manually screened by users of an online citizen science platform. Finally, all annotations were quality checked by experts. We used the dataset to train and compare the performance of selected You Only Look Once (YOLO) deep learning algorithms. We show that these models detect and classify small insects in complex scenes with unprecedented accuracy. The best performing YOLOv5 model consistently identifies nine dominant insect species that play important roles in pollination and pest control across Europe. The model reached an average precision of 92.7% and recall of 93.8% in detection and classification across species. Importantly, when presented with uncommon or unclear insects not seen during training, our model detects 80% of individuals and usually interprets them as closely related species. This is a useful property to (1) detect rare insects for which training data are absent, and (2) generate new training data to correctly identify those insects in future. Our camera system, dataset and deep learning framework show promising results in non-destructive monitoring of insects. Furthermore, resulting data are useful to quantify phenology, abundance, and foraging behaviour of flower-visiting insects. Above all, this dataset represents a critical first benchmark for future development and evaluation of deep learning models for insect detection and identification.

Present study was conducted in Mohal Khad, Kullu Valley, Himachal Pradesh, investigated the diversity and flower-visiting frequency of insect pollinators on mustard (Brassica campestris). The visual sampling method during the peak bloom of mustards recorded a total of 24 species of insect pollinators from 4 orders, 13 families, and 19 genera, with Hymenoptera being the dominant order, while Coleoptera had the least presence. The Indian honeybee (Apis cerana indica) was the most frequently observed visitor, highlighting its significant role in pollination. Mustards act as an essential foraging source for insect pollinators during early spring in temperate regions, where they bloom earlier than other temperate crops. The findings help emphasize the importance of mustard cultivation along with the conservation of native species, Apis cerana indica, over exotic ones for sustainable agriculture in the Himalayan region.

Abstract Animal pollinators are vital for the reproduction of ~90% of flowering plants. However, many of these pollinating species are experiencing declines globally, making effective pollinator monitoring methods more important than ever before. Pollinators can leave DNA on the flowers they visit, and metabarcoding of these environmental DNA (eDNA) traces provides an opportunity to detect the presence of flower visitors. Our study, collecting flowers from seven plant species with diverse floral morphologies, for eDNA metabarcoding analysis, illustrated the value of this novel survey tool. eDNA metabarcoding using three assays, including one developed in this study to target common bush birds, recorded more animal species visiting flowers than visual surveys conducted concurrently, including birds, bees, and other species. We also recorded the presence of a flower visit from a western pygmy possum; to our knowledge this is the first eDNA metabarcoding study to simultaneously identify the interaction of insect, mammal, and bird species with flowers. The highest diversity of taxa was detected on large inflorescence flower types found on Banksia arborea and Grevillea georgeana. The study demonstrates that the ease of sample collection and the robustness of the metabarcoding methodology has profound implications for future management of biodiversity, allowing us to monitor both plants and their attendant cohort of potential pollinators. This opens avenues for rapid and efficient comparison of biodiversity and ecosystem health between different sites and may provide insights into surrogate pollinators in the event of pollinator declines.

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Flower-visiting insects are essential in maintaining a healthy and productive agricultural landscape through ecosystem services such as pollination. Fruits are important sources of vitamins and micronutrients, and several fruit crops depend on animal pollination, which enhances their nutritional content. Besides honey bees, apple orchards can sustain a large number of arthropod species that also aid in pollination. In this present study, we assessed the diversity and abundance of insect flower visitors in six apple orchards in Nyeri and Laikipia East. Six plots, each with more than 20 apple trees, were purposefully selected. Data were collected through timed visual searches and sweep netting. Sampling was done from 0900 hours to 1700 hours, six days a week, for five months consecutively in 2019. Diversity indices were computed using the Shannon-Wiener diversity index, while abundance patterns were displayed using species abundance curves. Differences in species diversity and abundance between sites were compared using a one-way analysis of variance. A total of 1,221 insects belonging to 23 families, 82 species, and 4 orders (Hymenoptera, Lepidoptera, Coleoptera, and Diptera) were recorded. The order Hymenoptera (bees, wasps, and ants) was the most abundant, with 1,176 individuals, and had the most species-rich taxa, with 56 species in 9 families. The order Coleoptera (beetles) was second, with 26 individuals and 12 species in 6 families. Lepidoptera were the least abundant with 10 individuals and the least species-rich taxa with 7 species in 5 families, followed closely by Diptera with 7 individuals and 7 species in 3 families. There were significant differences in flower visitors’ composition among the six sites. The study provides important information on the status of key apple flower visitors, which can guide orchard management practises to increase apple yield through pollinator conservation. Conserving apple pollinators will enhance fruit production, promote the livelihoods of farmers, and contribute to the national economy.

Buckwheat (<i>Fagopyrum esculentum</i>) is an important source of nutrition for humans, providing essential nutrients such as protein, fiber, vitamins, and minerals. Its cultivation is highly attractive to flower-visiting insects, which find abundant nectar and a moderate amount of pollen grains. This study aimed to characterize the taxonomic diversity and composition of flower-visiting insect communities in buckwheat crops across two sites in Chitwan district, Nepal and to assess whether temperature and relative humidity influence community structure. We further quantified the contribution of insect pollination to buckwheat yield by comparing pollinator-excluded plots (net-covered) with open-pollinated plots. In addition, we estimated the economic value of insect-mediated pollination and the nutritional contribution of buckwheat production on a per capita basis. Data were analyzed using non-metric multidimensional scaling, permutational multivariate analysis of variance, similarity percentage analysis, and (generalized) linear mixed-effects models. We found significant differences in flower-visiting insect community composition between the two study sites, independent of temperature and relative humidity, with twelve taxa contributing most to this dissimilarity. Open-pollinated plots exhibited higher buckwheat yields than pollinator-excluded plots, highlighting the importance of insect visitation for crop production. Despite the presence of managed <i>Apis</i> species, we recorded frequent visitation by flies and solitary bees, indicating that these taxa are likely important contributors to buckwheat pollination at local scales. Similarly, insect-mediated pollination significantly increased buckwheat production, and its absence would result in substantial economic losses of USD 2.6 million and reduced nutritional contributions, highlighting the vulnerability of buckwheat-based food security for the Nepalese communities due to pollinator decline.

Introduction Heterogeneity in composition and spatial configuration of landscape elements support diversity and abundance of flower-visiting insects, but this is likely dependent on taxonomic group, spatial scale, weather and climatic conditions, and is particularly impacted by agricultural intensification. Here, we analyzed the impacts of both aspects of landscape heterogeneity and the role of climatic and weather conditions on pollinating insect communities in two economically important mass-flowering crops across Europe. Methods Using a standardized approach, we collected data on the abundance of five insect groups (honey bees, bumble bees, other bees, hover flies and butterflies) in eight oilseed rape and eight apple orchard sites (in crops and adjacent crop margins), across eight European countries (128 sites in total) encompassing four biogeographic regions, and quantified habitat heterogeneity by calculating relevant landscape metrics for composition (proportion and diversity of land-use types) and configuration (the aggregation and isolation of land-use patches). Results We found that flower-visiting insects responded to landscape and climate parameters in taxon- and crop-specific ways. For example, landscape diversity was positively correlated with honey bee and solitary bee abundance in oilseed rape fields, and hover fly abundance in apple orchards. In apple sites, the total abundance of all pollinators, and particularly bumble bees and solitary bees, decreased with an increasing proportion of orchards in the surrounding landscape. In oilseed rape sites, less-intensively managed habitats (i.e., woodland, grassland, meadows, and hedgerows) positively influenced all pollinators, particularly bumble bees and butterflies. Additionally, our data showed that daily and annual temperature, as well as annual precipitation and precipitation seasonality, affects the abundance of flower-visiting insects, although, again, these impacts appeared to be taxon- or crop-specific. Discussion Thus, in the context of global change, our findings emphasize the importance of understanding the role of taxon-specific responses to both changes in land use and climate, to ensure continued delivery of pollination services to pollinator-dependent crops.

Agroecosystems are often impoverished ecosystems, but they can host diverse communities of insects which provide ecosystem services. Specifically, crops may benefit from insect pollinators that increase their quantity and quality of yields. Basic knowledge is still needed regarding the identity, diversity, abundance, and ecology of insect pollinators in many parts of the world, especially in low and middle-income countries. In this study we investigate the potential of agroecosystems and crops in Morocco to host a high diversity of insect pollinators. We sampled insects in four eco-climatic regions encompassing a total of 22 crops for 2 years (2018–2019). After describing the general pattern of diversity and abundance of insect pollinators, we focused our comparative analyses on bees as they are known to be the most efficient and abundant group of insect pollinators. We recorded a total of 53,361 insect pollinators in all agroecosystems among which 37,091 were visiting crop flowers. Bees were by far the most abundant group visiting crops. Honeybees represented 49% of crop visitors followed by wild bees representing 33% of relative abundance. Three genera ( Lasioglossum , Andrena , and Xylocopa ) represented 53% of the total abundance of wild bees visiting crops. We identified a total of 213 species visiting crops (22% of national wild bee species richness). A comparison of the abundance, species richness, and community composition of wild bees visiting the same crops showed significant inter-regional differences for zucchini, faba bean, and eggplant. This study highlights the high diversity of pollinators in Moroccan agroecosystems and represents an important step toward exploring the Moroccan pollinator fauna. It provides basic information for future studies on pollinator conservation and pollination services.

Weed flowers constitute important resources for many insects. In that regard, vineyards represent an interesting agroecosystem, due to the wide spacing between rows, which allows the development of spontaneous vegetation. Their floral potential depend

Over the past two decades, the cultivated area of oilseed rape (Brassica napus L. or OSR), a mass-flowering crop, has markedly increased in Europe in response to bioenergy demands. As well as representing a major shift in floral composition across the landscape, mass-flowering OSR may alter pollination services to other simultaneously blooming crops, either decreasing pollination via competition for pollinators or facilitating it via pollinator spill-over. Apple (Malus domestica Borkh.) is an economically important, obligately insect-pollinated fruit crop that co-flowers with OSR. Using twelve independent apple orchards varying in the percentage of OSR in the surrounding landscape, we investigated the effect of OSR on pollinators and pollination of co-blooming apple. We collected bees with pan traps and quantified flower visitors during transect walks in both crops and we experimentally measured pollination service provision to apple as fruit and seed set. We confirm that apples are highly dependent on animal pollination and report pollination limitation in our apple orchards. Honey bees were the numerically dominant visitors of apple flowers observed during transect walks. Though their numbers dropped with an increasing percentage of OSR in the landscape, the number of bumble bees visiting apple flowers remained stable and those of other wild bees rose. The pan trapped Shannon diversity of bees remained constant. We could not detect an effect of OSR in the landscape on apple fruit set or seed set, both of which remained stable. Local wild bee populations might compensate for the loss of honey bees in the provision of pollination services in apple, providing especially effective pollination. Our results underscore not only the dominant role of bees in apple pollination but also the importance of wild bee conservation for providing pollination insurance and stability of apple crop yields under changing agricultural policies and cropping practices.

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Abstract Agricultural intensification has been implicated in global biodiversity declines. In the European Union, agri‐environmental schemes are designed to address this. For pollinating insects, funding has been provided to sow wildflower mixes. However, previous research indicates that a suite of agricultural weeds are also of great importance to pollinators. Here, we compare the biodiversity associated with the species which are considered harmful to agricultural production and legally deemed as ‘injurious’ by the United Kingdom 1959 Weeds Act (common ragwort Jacobaea vulgaris , creeping thistle Cirsium arvense , spear thistle C. vulgare , curled dock Rumex crispus and broadleaved dock R. obtusifolius ), with plant species recommended for pollinator‐targeted agri‐environmental options. In our field study, the abundance and diversity of pollinators visiting the weed species averaged twice that of the recommended plants and included the main insect orders (Coleoptera, Diptera, Hymenoptera and Lepidoptera). This relationship was also seen in a meta‐analysis of literature data, which indicates that fourfold more flower‐visitor species and fivefold more conservation‐listed species are associated with the weeds. Additionally, the literature shows that twice the number of herbivorous insect species are associated with these plants. We suggest that several factors are responsible for this pattern. Injurious weed species are widely distributed, their flower morphology allows access to a wide variety of pollinator species, and they produce, on average, four times more nectar sugar than the recommended plant species. Freedom of information requests to public bodies such as local councils, Natural England and Highways England indicate that c . £10 million per year is spent controlling injurious weeds. Meanwhile, the cost of the four pollinator‐targeted agri‐environmental options in the United Kingdom exceeds £40 m annually. Synthesis and applications . Our results clearly show that weeds have an underappreciated value to biodiversity. Unfortunately, current UK agricultural policy encourages neither land sparing for nor land sharing with weeds. The UK government is, however, currently committed to overhauling agricultural payments to encourage more wildlife‐ and climate‐friendly practices. Thus, the challenge of reconciling the conflicts between agricultural production and these native and biodiverse species should be a renewed priority to land managers, researchers and policymakers.

Roads and road verges can potentially have opposite impacts on organisms that move through the landscape. While road verges can be habitat for a large number of species, and have been proposed to act as dispersal corridors, roads can act as barriers to movement. This duality of roads and road verges has however rarely been assessed simultaneously, and it is unknown to what degree it depends on the amount of traffic on the road and on the habitat quality of the road verge. We used fluorescent powdered dye to track movements of flower‐visiting insects along roads with varying traffic intensity, and in verges with contrasting habitat quality (flowering plant species richness and flower density). Insect movements along road verges were more frequent than movements into the adjacent habitats, indicating that verges act as corridors. The frequency of movements that required crossing the road was lower compared to the frequency of movements that did not, suggesting that roads are barriers. The movement patterns were independent of traffic intensity, but the barrier effect was stronger when the road verge had a higher density of flower resources. The effect of roads as a barrier and of the road verges as corridors were independent of each other. Our results suggest that flower‐visiting insects tend to remain longer in road verges with high density of flowers and we therefore suggest that managing road verge habitats for an increased plant diversity will mitigate the known negative impacts of roads on insect populations.

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Flowers come in a variety of colours, shapes, sizes and odours. Flowers also differ in the quality and quantity of nutritional reward they provide to entice potential pollinators to visit. Given this diversity, generalist flower-visiting insects face the considerable challenge of deciding which flowers to feed on and which to ignore. Working with real flowers poses logistical challenges due to correlations between flower traits, maintenance costs and uncontrolled variables. Here, we overcome this challenge by designing multimodal artificial flowers that varied in visual, olfactory and reward attributes. We used artificial flowers to investigate the impact of seven floral attributes (three visual cues, two olfactory cues and two rewarding attributes) on flower visitation and species richness. We investigated how flower attributes influenced two phases of the decision-making process: the decision to land on a flower, and the decision to feed on a flower. Artificial flowers attracted 890 individual insects representing 15 morphospecies spanning seven arthropod orders. Honeybees were the most common visitors accounting for 46% of visitors. Higher visitation rates were driven by the presence of nectar, the presence of linalool, flower shape and flower colour and was negatively impacted by the presence of citral. Species richness was driven by the presence of nectar, the presence of linalool and flower colour. For hymenopterans, the probability of landing on the artificial flowers was influenced by the presence of nectar or pollen, shape and the presence of citral and/or linalool. The probability of feeding increased when flowers contained nectar. For dipterans, the probability of landing on artificial flowers increased when the flower was yellow and contained linalool. The probability of feeding increased when flowers contained pollen, nectar and linalool. Our results demonstrate the multi-attribute nature of flower preferences and highlight the usefulness of artificial flowers as tools for studying flower visitation in wild insects.

This study examined if weeds could serve as insectary plants to increase beneficial insect abundance and diversity in mango cultivation in southern Florida. Additionally, we examined how weed presence affects mango tree soil health. We found that weeds significantly increased pollinating and parasitoid insect abundance and diversity. Eight insect orders and eighteen families were significantly more abundant on mango trees with weeds growing beneath them than those where weeds were removed. There was no difference in predatory insects between treatments, and slightly more herbivorous insects on weedy mango trees. Pollinating insects visiting mango flowers in the weed treatment were significantly greater, as well as spiders on weedy mango trees. However, there were more lacewings (Neuroptera) observed on the mango trees without weeds, and leaf chlorophyll in the old and new mango leaves was significantly greater, in the weed-free treatment. Soil conditions, however, significantly improved in soil carbon and a greater pH reduction in the presence of weeds, though weeds affected neither soil nitrogen, phosphorous, nor chlorophyll in productive green leaves. These results show that a tolerable level of selective weed species' presence may benefit insect, plant, and soil biodiversity in farms. This is important in increasing production, sustainability, and biodiversity in agriculture, which otherwise may be deficient in non-crop life.

Over one third of crops are animal pollinated, with insects being the largest group. In some crops, including strawberries, fruit yield, weight, quality, aesthetics and shelf life increase with insect pollination. Many crops are protected from extreme weather in polytunnels, but the impacts of polytunnels on insects are poorly understood. Polytunnels could reduce pollination services, especially if insects have access issues. Here we examine the distribution and activity of honeybees and non-honeybee wild insects on a commercial fruit farm. We evaluated whether insect distributions are impacted by flower type (strawberry; raspberry; weed), or distance from polytunnel edges. We compared passive pan-trapping and active quadrat observations to establish their suitability for monitoring insect distribution and behaviour on a farm. To understand the relative value of honeybees compared to other insects for strawberry pollination, the primary crop at the site, we enhanced our observations with video data analysed using insect tracking software to document the time spent by insects on flowers. The results show honeybees strongly prefer raspberry and weed flowers over strawberry flowers and that location within the polytunnel impacts insect distributions. Consistent with recent studies, we also show that pan-traps are ineffective to sample honeybee numbers. While the pan-traps and quadrat observations tend to suggest that investment in managed honeybees for strawberry pollination might be ineffective due to consistent low numbers within the crop, the camera data provides contrary evidence. Although honeybees were relatively scarce among strawberry crops, camera data shows they spent more time visiting flowers than other insects. Our results demonstrate that a commercial fruit farm is a complex ecosystem influencing pollinator diversity and abundance through a range of factors. We show that monitoring methods may differ in their valuation of relative contributions of insects to crop pollination.

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Abstract Apples are a major crop globally, including in Tasmania (Australia) – known as ‘the Apple Isle’ owing to the key role of apples in Tasmania's history and economy. Most apple cultivars are obligate entomophilous species, and fruit quantity, quality and economic value are enhanced under insect pollination. Whilst the introduced European honey bee ( Apis mellifera ) is often assumed to be the main pollinator of apple in most regions of the world, including Australia, there is an increasing interest in alternative pollinators. The pollinator community of Tasmanian apple crops, however, has never been assessed. In this study, we surveyed four apple orchards for 3 days each during peak bloom in the Huon Valley region to characterise bee assemblages visiting blooming apple trees and the native bee fauna associated with surrounding flowering vegetation. Our results show that honey bees were the predominant visitors to apple blossoms (90.7% of visits), followed by the introduced bumble bee Bombus terrestris (5.9% of visits), with only a minor contribution by native bees (3.3% of visits). Twenty‐six species of native bees were collected in total, of which only 10 species (five Exoneura (Apidae), four Lasioglossum (Halictidae) and one Euryglossa (Colletidae) species) were collected from apple blossoms, with Exoneura being the most abundant visitors. Few native bees were captured on apple blossoms, however co‐blooming surrounding native vegetation, as well exotic flowers, hosted a high diversity and abundance of native bees. Site conditions influenced community composition, including abundance and representation of introduced bees compared to native bees visiting apples. Additionally, warmer temperatures favoured native bees. Collectively, our results suggest that Tasmania's apple production in its current state is unlikely to rely exclusively on native pollinators. Native bees nevertheless warrant conservation in such an insular crop production system. This can be achievable through retaining native flowering plants and even exotic non‐crop flowers in and around orchards. Promoting the diversity and abundance of native bees through habitat enhancement may have additional benefits, such as filling current and future pollination demands and gaps, a key strategy under scenarios of climate change.

Abstract Drastic reductions of insect diversity and abundance have been observed in highly fragmented agricultural landscapes of central Europe. Declines of pollinators may have detrimental effects on the reproduction of wild insect‐pollinated plants as well as the yield of crops. In order to mitigate such impacts, sown flower strips on arable land within Agri‐Environment Climate Schemes (AECS) are supported across EU countries. However, it is not clear whether sown flower strips provide equivalent benefits to wild flower‐visiting insects as semi‐natural habitats. Here, we apply plant–pollinator network approach to evaluate the function of sown flower strips for the communities of wild bees. We compared the structural characteristics and the robustness of plant–pollinator networks in sown flower strips and nearby semi‐natural habitats in seven sites in the Czech Republic. We also quantified the importance of individual plant species for bees based on simulations of plant–pollinator extinction cascades. We found that assemblages of plants and pollinators were less diverse in sown flower strips than in semi‐natural habitats, more generalised, and more nested. However, we did not find any significant differences in network robustness to plant–pollinator coextinctions. Further, simulations revealed large variation in the functional importance among plant species from both habitats. We conclude that although the analysis of network robustness suggested that plants in the sown flower strips and semi‐natural habitats were functionally equivalent, this masked important differences between the two habitats. From a conservation point of view, semi‐natural habitats were superior in supporting a more diverse community of solitary bees and bumblebees, likely because of their greater longevity and higher habitat heterogeneity.

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Abstract Pollinating insects provide pollination services to many crop species, including sweet cherry ( Prunus avium L.), and this can be delivered by both managed and wild pollinators. Managed pollinators are often used to pollinate a range of fruit crops, but increasingly the role of wild insects is being studied. However, the importance of pollinator species depends on their relative abundance and pollination effectiveness, which depends on their foraging activity and their variability throughout the day. In this study, insect visitors of blossoms were observed in commercial sweet cherry orchards to explore abundance, diversity and pollination foraging behaviour of different insect pollinator groups throughout the day. A total of 1,174 pollinators from 31 different species were recorded visiting cherry blossoms over 2 years, of which 71.0% of total visits were by managed pollinators (western honeybee, Apis mellifera L. and buff‐tailed bumblebee, Bombus terrestris L.) compared to 29.0% by wild pollinators. On average, solitary bees visited a sweet cherry blossom for the longest duration (20.7 (±2.0 SE ) seconds), whereas wild queen bumblebees visited the greatest number of flowers per minute (mean of 19.0 (±1.3 SE )). As both these pollinator groups contacted cherry stigmas more often and moved more frequently between tree rows than managed bees and hoverflies, they are more likely to facilitate cross‐pollination. The different pollinator groups also showed variation in behavioural parameters throughout the day, but less variation was recorded when all pollinator groups were considered altogether. This suggests diverse pollinator communities might be expected to provide a more stable pollination service to sweet cherry. This study demonstrates that whilst cherry blossoms were more frequently visited by managed pollinators, wild solitary bee and bumblebee behaviours are likely to be more effective at enhancing pollination in sweet cherry orchards, which, in turn, might lead to increased yields.

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Salacca (Salacca spp.) is a dioecious plant with male and female flowers existing on a different plant, therefore requires agents of pollination. More than thirty cultivars of salacca are found in Indonesia. This research aimed to study the diversity of visiting insects on the three varieties of salacca, i.e., Pondoh, Mawar and Kalimantan in Indonesia, as well measuring the pollen load on the pollinators. The visiting insects were observed on the male flowers using the fix sample method in ten minutes for fifteen days. Results showed that nine insect species visited the flowers and three species were potential pollinators, i.e., Nodocnemis sp., Apis cerana and Tetragonula laeviceps. The highest diversity of visiting insects was found in Kalimantan salacca (H' = 1.31, E = 0.74) followed by Pondoh salacca (H' = 0.72, E = 0.23) and Mawar salacca (H' = 0.51, E = 0.19). There was no dominant species found in Kalimantan salacca. The high similarity of visiting insects was found in Pondoh-Mawar salacca (SN = 0.59). Furthermore, the pollen load on Nodocnemis sp., A. cerana and T. laeviceps were about 127, 7893, and 4228 pollen grains, respectively.

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Abstract There is increasing land use change for solar parks and growing recognition that they could be used to support insect pollinators. However, understanding of pollinator response to solar park developments is limited and empirical data are lacking. We combine field observations with landcover data to quantify the impact of on‐site floral resources and surrounding landscape characteristics on solar park pollinator abundance and species richness. We surveyed pollinators and flowering plants at 15 solar parks across England in 2021, used a landcover map to assess the surrounding high‐quality habitat and aerial imagery to measure woody linear features (hedgerows, woodland edges and lines of trees). In total, 1397 pollinators were recorded, including 899 butterflies (64%), 171 hoverflies (12%), 161 bumble bees (12%), 157 moths (11%), and nine honeybees (&lt;1%). At least 30 pollinator species were observed, the majority of which were common, generalist species. Pollinator biodiversity varied between solar parks and was explained by a combination of on‐site floral resources and surrounding landscape characteristics. Floral species richness was the most influential on‐site characteristic and woody linear feature density generally had a greater impact than the cover of surrounding high‐quality habitats, although drivers differed by pollinator group. Our findings suggest that a range of factors affect pollinator biodiversity at solar parks, but maximising floral resources within a park through appropriate management actions may be the most achievable way to support most pollinator groups, especially where solar parks are located in resource‐poor, disconnected landscapes.

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Forests are crucial for sustainable land planning and they are believed to buffer land use changes and to promote human wellbeing and biodiversity. However, it is not clear how forests could influence bee diversity, that is responsible for the pollination ecosystem service. Here, we investigated bee biodiversity in relation to forests patches in agricultural and urban landscapes, and to urban forest features and flower richness in green areas; we also quantified the amount of pollen transported in relation to nesting and body-size traits. In the results, the importance of landscape variables depended on the macrohabitat: in agricultural lands, bee abundance increased with the number, distance and intermediate cover of forest patches, but in urban environments only forest shape complexity contributed. Moreover, in urban parks with mature urban forests, cavity-nesting bee richness increased with large logs and decaying wood, while bee richness increased with flower species richness in meadows adjacent to forests. Hence, open spaces rich in flowers and forests managed to keep understorey wood are relevant for increasing urban bee richness. Forest management could shape the occurrence of certain bee traits, but the nesting substrate trait will not modify the potential pollination ecosystem service because the amount of pollen transported related more to the body size. This study emphasises the importance of forested areas for bees in agricultural and urban environments. The results could contribute to develop biodiversity-friendly landscape planning and forest management practices when they are focused on ensuring wood elements, flowers and specific forest patch configurations sustaining bees.

Agricultural expansion and intensification have boosted global food production but have come at the cost of environmental degradation and biodiversity loss. Biodiversity-friendly farming that boosts ecosystem services, such as pollination and natural pest control, is widely being advocated to maintain and improve agricultural productivity while safeguarding biodiversity. A vast body of evidence showing the agronomic benefits of enhanced ecosystem service delivery represent important incentives to adopt practices enhancing biodiversity. However, the costs of biodiversity-friendly management are rarely taken into account and may represent a major barrier impeding uptake by farmers. Whether and how biodiversity conservation, ecosystem service delivery, and farm profit can go hand in hand is unknown. Here, we quantify the ecological, agronomic, and net economic benefits of biodiversity-friendly farming in an intensive grassland-sunflower system in Southwest France. We found that reducing land-use intensity on agricultural grasslands drastically enhances flower availability and wild bee diversity, including rare species. Biodiversity-friendly management on grasslands furthermore resulted in an up to 17% higher revenue on neighboring sunflower fields through positive effects on pollination service delivery. However, the opportunity costs of reduced grassland forage yields consistently exceeded the economic benefits of enhanced sunflower pollination. Our results highlight that profitability is often a key constraint hampering adoption of biodiversity-based farming and uptake critically depends on society's willingness to pay for associated delivery of public goods such as biodiversity.

Pollinator decline is one of the most significant ecological problems of the 21 st century. This decline threatens human food security and global economy. In order to address this problem governments across Europe and the USA have introduced national pollinator conservation strategies. These strategies, however, significantly differ in approaches to conservation. The differences at least in part stem from lack of consensus in the literature on whether pollinator biodiversity or abundance of a few common species determines crop pollination. Critical evaluation of empirical evidence available to date outlined in this paper suggests that pollinator biodiversity rather than abundance of dominant species determine quality, magnitude and resilience of pollination ecosystem services to agriculture. In order to maintain pollinator biodiversity conservation strategies and initiatives should focus on enhancing habitat quality, complementarity and connectivity, rather than solely on increasing floral resource abundance and diversity within farmland fields. Conservation strategies currently underway need to be improved to address all three factors through landscape scale interventions. Countries that intend to design and introduce pollinator conservation strategies should take best practices from several existing strategies rather than choosing a single strategy as an example.

While the Convention on Biological Diversity employs a habitat-oriented definition of soil biodiversity including all kinds of species living in soil, the Food and Agriculture Organization, since 2002 assigned to safeguard soil biodiversity, excludes them by focusing on species directly providing four ecosystem services contributing to soil quality and functions: nutrient cycling, regulation of water flow and storage, soil structure maintenance and erosion control, and carbon storage and regulation of atmospheric composition. Many solitary wasps and 70% of wild bees nest below ground and require protection during this long and crucial period of their lifecycle. Recent research has demonstrated the extent of threats to which ground-nesting pollinators are exposed, for example, chemicals and deep tillage. Ground-nesting pollinators change soil texture directly by digging cavities, but more importantly by their indirect contribution to soil quality and functions: 87% of all flowering plants require pollinators. Without pollinators, soil would lose all ecosystem services provided by these flowering plants, for example, litter, shade, roots for habitats, and erosion control. Above- and belowground biota are in constant interaction. Therefore, and in line with the Convention's definition, the key stakeholder, the Food and Agriculture Organization should protect ground-nesting pollinators explicitly within soil biodiversity conservation.

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Abstract The article presents the results of long-term observations and a comparative analysis of changes in the biodiversity of insect pollinators and entomophilic plants of two closely spaced biocenoses (Test plots 1 and 2). In the initial period of observation, both sites had a comparable ecological state and relatively high biodiversity of pollinators and plants, Apidae (55%) prevailed in Test plot 2, and Diptera dominated in Test plot 1 (32.7%). The number of pollinators was approximately 44% higher in Test plot 2 than in Test plot 1. The number of pollinators, their species diversity and plants decreased fivefold in the biocenosis of Test plot 1 in the second observation period (after 15 years), signs of degradation of the phytocenosis of the Test plot 1 were observed. Woody vegetation and cereals predominated in the phytocenosis. The number of pollinators and their species diversity increased (approximately 2 times) in the biocenosis of Test plot 2, Apidae dominated in this area (about 32%). High number of legumes in the herbage and the intensive pollination activity of bees and other pollinators were undoubtedly one of the factors for a stable state of the biocenosis of Test plot 2. The article indicates that the controlled anthropogenic impact on biocenoses, in particular the creation of a dense grassy cover based on hybrid clover, the creation of nesting spots for bumblebees and single bees, the development of beekeeping will allow for targeted impact on biocenoses to create their stable state with a high level of biodiversity and productivity.

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&amp;lt;p&amp;gt;As solar photovoltaic make a greater contribution to the energy mix, there will be increasing land use change for solar parks. Land use change can affect biodiversity across spatial scales and opportunities to incorporate biodiversity benefits into the energy transition are increasingly being recognised. For example, solar parks could support insect pollinators through providing critical resources such as flowering plants. However, understanding of pollinator response to solar park developments is currently limited and empirical data are lacking. To address this knowledge gap, we surveyed bumble bees, butterflies and flowering plants between July and September across 15 solar parks in the UK. We also investigated the composition and connectivity of the landscapes surrounding each solar park using landcover data and a GIS, allowing us to explore the impacts of on-site floral resources and surrounding landscape characteristics on bumble bee and butterfly abundance and diversity. We found that bumble bee and butterfly biodiversity varied across solar parks, but overall butterflies were more than five times more abundant than bumble bees. Pollinator biodiversity was impacted by both on-site resources and landscape characteristics. However, characteristics of the floral resources on site appeared to be the most important factors, with increases in floral diversity, floral cover and vegetation height associated with increases in pollinator abundance and diversity. Our findings suggest that local and landscape scale factors affect pollinator biodiversity on solar parks, but solar parks that provide diverse and abundant flowering plants may be best placed to support pollinators. Incorporating this knowledge into existing and future solar park developments could promote benefits to insect pollinators alongside the energy transition.&amp;lt;/p&amp;gt;

The dilution effect hypothesis posits that increasing biodiversity reduces infectious disease transmission. Here, we propose that habitat quality might modulate this negative biodiversity-disease relationship. Habitat may influence pathogen prevalence directly by affecting host traits like nutrition and immune response (we coined the term "habitat-disease relationship" to describe this phenomenon) or indirectly by changing host biodiversity (biodiversity-disease relationship). We used a path model to test the relative strength of links between habitat, biodiversity, and pathogen prevalence in a pollinator-virus system. High-quality habitat metrics were directly associated with viral prevalence, providing evidence for a habitat-disease relationship. However, the strength and direction of specific habitat effects on viral prevalence varied based on the characteristics of the habitat, host, and pathogen. In general, more natural area and richness of land-cover types were directly associated with increased viral prevalence, whereas greater floral density was associated with reduced viral prevalence. More natural habitat was also indirectly associated with reduced prevalence of two key viruses (black queen cell virus and deformed wing virus) via increased pollinator species richness, providing evidence for a habitat-mediated dilution effect on viral prevalence. Biodiversity-disease relationships varied across viruses, with the prevalence of sacbrood virus not being associated with any habitat quality or pollinator community metrics. Across all viruses and hosts, habitat-disease and biodiversity-disease paths had effects of similar magnitude on viral prevalence. Therefore, habitat quality is a key driver of variation in pathogen prevalence among communities via both direct habitat-disease and indirect biodiversity-disease pathways, though the specific patterns varied among different viruses and host species. Critically, habitat-disease relationships could either contribute to or obscure dilution effects in natural systems depending on the relative strength and direction of the habitat-disease and biodiversity-disease pathways in that host-pathogen system. Therefore, habitat may be an important driver in the complex interactions between hosts and pathogens.

Pollinators are on the decline and loss of flower resources play a major role. This raises concerns regarding production of insect-pollinated crops and therefore food security. There is urgency to mitigate the decline through creation of farming systems that encourage flower-rich habitats. Cowpea is a crop that produces pollen and nectar attractive to pollinators. Twenty-four cowpea varieties were planted, and the number of pollinators were counted using three sampling methods: pan traps, sticky traps, and direct visual counts. Five pollinator types (honey bees, bumble bees, carpenter bees, wasps, and butterflies and moths), 11 and 16 pollinator families were recorded from direct visual counts, pan and sticky traps, respectively. Pollinator distribution varied significantly among varieties and sampling methods, with highest number on Penny Rile (546.0 ± 38.6) and lowest (214.8 ± 29.2) in Iron and Clay. Sticky traps accounted for 45%, direct visual counts (31%), and pan traps (23%) of pollinators. Pollinators captured by pan traps were more diverse than the other methods. The relationship between number of pollinators and number of flowers was significant (<i>r</i> ² = 0.3; <i>p</i> = 0.009). Cowpea can increase resources for pollinators and could be used to improve pollinator abundance and diversity in different farming systems.

Insect pollinator biodiversity is changing rapidly, with potential consequences for the provision of crop pollination. However, the role of land use-climate interactions in pollinator biodiversity changes, as well as consequent economic effects via changes in crop pollination, remains poorly understood. We present a global assessment of the interactive effects of climate change and land use on pollinator abundance and richness and predictions of the risk to crop pollination from the inferred changes. Using a dataset containing 2673 sites and 3080 insect pollinator species, we show that the interactive combination of agriculture and climate change is associated with large reductions in insect pollinators. As a result, it is expected that the tropics will experience the greatest risk to crop production from pollinator losses. Localized risk is highest and predicted to increase most rapidly, in regions of sub-Saharan Africa, northern South America, and Southeast Asia. Via pollinator loss alone, climate change and agricultural land use could be a risk to human well-being.

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Context The Southwest Australian Floristic Region has exceptional plant evolutionary complexity for fire, nutrition and pollination traits. Aims Our aim was to allocate pollination strategies to all vascular plants in this biodiversity hotspot by analysing existing and new data. Methods Here we assigned a flower syndrome to ~8800 plants in this region, using floral traits and visitation records for insects, birds or mammals, which were well correlated. Key results Specific insect relationships were most common (3383), especially with native bees (2410), including buzz pollination (450). Others were pollinated by wind (1054 plants), water (35) or had relatively unspecialised flowers visited by diverse insects (3026). Specific associations with flies (588) or butterflies and moths (165) were less common. Approximately 14% were primarily pollinated by birds (601) or birds and insects (583) – with much larger flowers (corresponding with bird bill lengths), and less insect-attracting colours (e.g. red or green). Non-flying mammals, especially honey possums, visit certain flowers along with birds. Pollination complexity peaked in the Myrtaceae (11% bird, 25% bird and insect), Fabaceae (2% bird, 46% bee, 2% buzz pollination) and Proteaceae (40% birds, 31% specific insects). Bird pollination also has multiple origins in the Ericaceae (8%), Haemodoraceae (20%), Rutaceae (16%), Pittosporaceae (14%) and Eremophila (45%). Extreme specialisations included secondary pollen presentation (1231), post-pollination colour change (72), mobile columns (310), explosive pollen release (137) and visual (209) or sexual (171) deception in orchids. Pollination trait complexity included &gt;275 evolutionary transitions, especially from insects to birds (130), more specific insects (100), or wind (15). These followed similar morphological pathways within families but differed between them. Conclusions This complexity appears to be globally unique, and peaks in highly speciose plant families with diversity centred in the region. Implications This has ecological and genetic consequences, especially for rare flora management, ecosystem restoration and assessing plant vulnerability to habitat degradation, fire and climate change.

Pollination is vital for ecosystem functioning, especially in biodiversity-rich regions like the Brazilian Cerrado. Our research establishes a comprehensive meta network of pollinator-plant interactions within this biome. We quantified the importance of different pollinator groups, identifying keystone species. We examined potential biases in sampling effort and the spatial behavior of interactions within the heterogeneous Cerrado plant physiognomies. Our investigation uncovered 1499 interactions among 293 plant species and 386 visitor species, with legitimate pollination accounting for 42.4% of the interactions. The network exhibited modularity, driven by bees and insects, with vertebrates bridging diurnal and nocturnal modules. While a generalized pattern emerged, high specialization existed within modules due to habitat diversity. Bees, particularly <i>Apis mellifera</i> (exotic) and <i>Trigona spinipes</i> (native), played central roles as network hubs. Hummingbirds and bats, engaged in specialized interactions showing strong connectivity within and between modules. Interestingly, invertebrate-vertebrate modules were more prevalent than expected in the meta network. However, a bias was evident, primarily within specific biogeographical districts with fragmented landscapes and intrusion from other biomes. Variations in plant species and endemism rates influenced pollinator occurrence and the Cerrado network topology. Our study offers valuable insights into pollinator-plant interactions within the Cerrado, encompassing both invertebrates and vertebrates. The modeled network represents a significant step in understanding the structural complexity of pollination networks, integrating partial networks from diverse pollination systems within heterogeneous habitats. Nevertheless, a biogeographical bias could limit a comprehensive understanding of network functionality across the Cerrado.

Abstract Protected areas (PAs) are vital in the global effort to preserve biodiversity, particularly for disturbance‐intolerant pollinator species in the tropics. As there is little information on the potential of PAs for pollinator conservation in sensitive tropical ecosystems, we assessed here insect pollinator diversity in protected vs. unprotected areas in two vegetation zones in Nigeria, within the West African Guinea Biodiversity Hotspot. We selected two land‐use types based on predominant canopy cover type (open and tree‐shaded habitats) and these were sampled in both protected and unprotected areas of tropical rain forest and savanna vegetation zones. Pollinator composition varied significantly between protected vs. unprotected areas in each vegetation zone, signifying both areas support unique assemblages of insect pollinators. However, pollinator diversity varied according to land‐use type (open vs. shaded habitats) rather than protected area per se, such that pollinators were more abundant and species‐rich in open habitat than shaded habitat. These findings emphasize that beyond the protection of ecosystems, fine scale habitat management promoting the availability of adequate floral resources in natural areas is critical for ensuring conservation of these pollinators in tropical ecosystems.

As the extent of oil palm (Elaeis guineensis) cultivation has expanded at the expense of tropical rainforests, enriching conventional large-scale oil palm plantations with native trees has been proposed as a strategy for restoring biodiversity and ecosystem function. However, how tree enrichment affects insect-mediated ecosystem functions is unknown. We investigated impacts on insect herbivory and pollination in the fourth year of a plantation-scale, long-term oil palm biodiversity enrichment experiment in Jambi, Sumatra, Indonesia. Within 48 plots systematically varying in size (25-1600 m² ) and planted tree species richness (one to six species), we collected response data on vegetation structure, understory insect abundances, and pollinator and herbivore activity on chili plants (Capsicum annuum), which served as indicators of insect-mediated ecosystem functions. We examined the independent effects of plot size, tree species richness, and tree identity on these response variables, using the linear model for random partitions design. The experimental treatments were most associated with vegetation structure: tree identity mattered, as the species Peronema canescens strongly decreased (by approximately one standard deviation) both canopy openness and understory vegetation cover; whereas tree richness only decreased understory flower density. Further, the smallest plots had the lowest understory flower density and richness, presumably because of lower light availability and colonization rates, respectively. Enrichment influenced herbivorous insects and natural enemies in the understory to a lesser extent: both groups had higher abundances in plots with two enrichment species planted, possibly because higher associated tree mortality created more habitat, while herbivores decreased with increasing tree species richness, in line with the resource concentration hypothesis. Linking relationships in structural equation models showed that the negative association between P. canescens and understory vegetation cover was mediated through canopy openness. Likewise, canopy openness mediated increases in herbivore and pollinator insect abundances. Higher pollinator visitation increased phytometer yield, while impacts of insect herbivores on yield were not apparent. Our results demonstrate that even at an early stage, different levels of ecological restoration influence insect-mediated ecosystem functions, mainly through canopy openness. These findings suggest that maintaining some canopy gaps while enrichment plots develop may be beneficial for increasing habitat heterogeneity and insect-mediated ecosystem functions.

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Biodiversity today has the unusual property that 85% of plant and animal species live on land rather than in the sea, and half of these live in tropical rainforests. An explosive boost to terrestrial diversity occurred from c. 100-50 million years ago, the Late Cretaceous and early Palaeogene. During this interval, the Earth-life system on land was reset, and the biosphere expanded to a new level of productivity, enhancing the capacity and species diversity of terrestrial environments. This boost in terrestrial biodiversity coincided with innovations in flowering plant biology and evolutionary ecology, including their flowers and efficiencies in reproduction; coevolution with animals, especially pollinators and herbivores; photosynthetic capacities; adaptability; and ability to modify habitats. The rise of angiosperms triggered a macroecological revolution on land and drove modern biodiversity in a secular, prolonged shift to new, high levels, a series of processes we name here the Angiosperm Terrestrial Revolution.

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There is increasing interest in evaluating biodiversity to preserve ecosystem services. Researchers can sustain policymakers by providing tools, such as indexes and indicators, that need constant implementation to become accepted standards. Implementation may vary from re-evaluation of existing indicators to introduction of new ones based on emerging threats to biodiversity. With the aim of contributing to the compelling need to estimate and counterbalance pollinator loss, we screened existing bioindicators. We first selected indexes/indicators applied to agricultural contexts and concurrently endorsed by a regulatory agency. We then extended our analysis to indexes/indicators based on arthropod taxa and formally recognized at least by national bodies. Our procedure identified a combination of surveys of various animal taxa and remote landscape analyses (e.g., using a GIS and other cartographic tools). When the animals are arthropods, most indexes/indicators can only address confined environments (e.g., grasslands, riversides). Indicator strength was improved by the simultaneous inclusion of biotic and abiotic components. Pollinator sensitivity to changes at micro-habitat level is widely appreciated and may help distinguish agricultural practices. A biodiversity index based on pollinators, including a wide monitoring scheme supplemented by citizen science, is currently fostered at the European level. The results obtained using such an index may finally enable focusing of strategic funding. Our analysis will help to reach this goal.

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Wild pollinators play a crucial role in maintaining healthy ecosystems and sustaining agricultural productivity. However, their survival is at risk due to habitat loss and land use changes, exacerbating the ongoing biodiversity crisis, and jeopardising global food security. We assessed the contribution of native vegetation cover to pollination and avocado crop yield by modelling the abundance of native bees and the pollination services they provide in agroecosystems of the Aconcagua River basin in Central Chile. This region stands as a critical biodiversity hotspot, currently confronted with the challenge of land use change, especially due to the expansion of avocado (Persea americana Mill.) monocultures. Our findings revealed a clear relationship between native bee abundance, pollination services, and avocado yield as a function of natural vegetation cover surrounding the crops. Areas with a higher proportion of native vegetation exhibited the most abundant supply of pollination services, while within avocado crops show lower levels of pollination support. A spatial mismatch between supply and demand for pollination revealed by our results indicates that agricultural expansion threatens native pollinators and agricultural yield production in this region. The development of pollination maps has been proposed as a strategic tool to guide land-use planning decisions within agricultural landscapes. Prioritizing the conservation of native vegetation or adopting biodiversity-friendly practices can help mitigate the effects of agricultural expansion on wild pollinators. These strategies are vital for safeguarding biodiversity, ensuring food security, and mitigating the far-reaching impacts of the current biodiversity crisis. [Figure: see text]

<i>Salix nigra</i> (black willow) is a widespread tree that hosts many species of polylectic hymenopterans and oligolectic bees of the genus <i>Andrena</i>. The early flowering of <i>S. nigra</i> makes it an important nutritive resource for arthropods emerging from hibernation. However, since <i>S. nigra</i> is dioecious, not all insect visits will lead to successful pollination. Using both visual observation and pan-trapping, we characterized the community of arthropods that visited <i>S. nigra</i> flowers and assessed differences among male and female trees as well as the chemical and visual drivers that influenced community composition across 3 years. We found that male trees consistently supported higher diversity of insects than female trees and only three insect species, all <i>Andrena</i> spp., consistently visited both sexes. Additionally, <i>Andrena nigrae</i>, which was the only insect that occurred more on female than male flowers, correlated strongly to volatile cues. This suggests that cross-pollinators cue into specific aspects of floral scent, but diversity of floral visitors is driven strongly by visual cues of yellow male pollen. Through time, the floral activity of two <i>Andrena</i> species remained stable, but <i>A. nigrae</i> visited less in 2017 when flowers bloomed earlier than other years. When native bee emergence does not synchronize with bloom, activity appears to be diminished which could threaten species that subsist on a single host. Despite the community diversity of <i>S. nigra</i> flowers, its productivity depends on a small fraction of species that are not threatened by competition, but rather rapidly changing conditions that lead to host-insect asynchrony.

As bees' main source of protein and lipids, pollen is critical for their development, reproduction, and health. Plant species vary considerably in the macronutrient content of their pollen, and research in bee model systems has established that this variation both modulates performance and guides floral choice. Yet, how variation in pollen chemistry shapes interactions between plants and bees in natural communities is an open question, essential for both understanding the nutritional dynamics of plant-pollinator mutualisms and informing their conservation. To fill this gap, we asked how pollen nutrition (relative protein and lipid content) sampled from 109 co-flowering plant species structured visitation patterns observed among 75 subgenera of pollen-collecting bees in the Great Basin/Eastern Sierra region (USA). We found that the degree of similarity in co-flowering plant species' pollen nutrition predicted similarity among their visitor communities, even after accounting for floral morphology and phylogeny. Consideration of pollen nutrition also shed light on the structure of this interaction network: Bee subgenera and plant genera were arranged into distinct, interconnected groups, delineated by differences in pollen macronutrient values, revealing potential nutritional niches. Importantly, variation in pollen nutrition alone (high in protein, high in lipid, or balanced) did not predict the diversity of bee visitors, indicating that plant species offering complementary pollen nutrition may be equally valuable in supporting bee diversity. Nutritional diversity should thus be a key consideration when selecting plants for habitat restoration, and a nutritionally explicit perspective is needed when considering reward systems involved in the community ecology of pollination.

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Although high visitation frequencies make honeybees important pollinators, they were less effective than the average bee and rarely the most effective pollinator of the plants they visit. As such, honeybees may be imperfect substitutes for the loss of wild pollinators, and safeguarding pollination will benefit from conservation of non-honeybee taxa.

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Agricultural intensification not only increases food production but also drives widespread biodiversity decline. Increasing landscape heterogeneity has been suggested to increase biodiversity across habitats, while increasing crop heterogeneity may support biodiversity within agroecosystems. These spatial heterogeneity effects can be partitioned into compositional (land-cover type diversity) and configurational heterogeneity (land-cover type arrangement), measured either for the crop mosaic or across the landscape for both crops and semi-natural habitats. However, studies have reported mixed responses of biodiversity to increases in these heterogeneity components across taxa and contexts. Our meta-analysis covering 6397 fields across 122 studies conducted in Asia, Europe, North and South America reveals consistently positive effects of crop and landscape heterogeneity, as well as compositional and configurational heterogeneity for plant, invertebrate, vertebrate, pollinator and predator biodiversity. Vertebrates and plants benefit more from landscape heterogeneity, while invertebrates derive similar benefits from both crop and landscape heterogeneity. Pollinators benefit more from configurational heterogeneity, but predators favour compositional heterogeneity. These positive effects are consistent for invertebrates and vertebrates in both tropical/subtropical and temperate agroecosystems, and in annual and perennial cropping systems, and at small to large spatial scales. Our results suggest that promoting increased landscape heterogeneity by diversifying crops and semi-natural habitats, as suggested in the current UN Decade on Ecosystem Restoration, is key for restoring biodiversity in agricultural landscapes.

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Due to the widespread use of pesticides and the lack of floral resources in many agricultural landscapes, beekeepers have moved numerous honey bee colonies in protected areas which could shelter an important diversity of wild bees. Here, we investigated the seasonal dynamics of the competition between honey bees and wild bees through a two‐year study of plant–bee networks in a Mediterranean protected area. We recorded the visitation rates of four bee groups: honey bees, small wild bees, large wild bees and bumblebees. Our study reveals that the competition for floral resources induced by honey bees is especially strong during the early spring and then decreases along the season for all groups of wild bees. We observed a competitive exclusion of all groups of wild bees illustrated by an avoidance of well‐flowered plant species in presence of honey bees. As a consequence, we detected a rewiring of large and small bee floral preferences linked to the presence of honey bees. In presence of honey bees, Rosmarinus officinalis and Cistus albidus were significantly less visited by large bees. This study underlines the need to mitigate the establishment of numerous honey bee colonies in protected areas as honey bees could strongly affect the foraging activity of wild bees.

Abstract Urban ecosystems can sustain populations of wild bees, partly because of their rich native and exotic floral resources. A better understanding of the urban bee diet, particularly at the larval stage, is necessary to understand biotic interactions and feeding behaviour in urban ecosystems, and to promote bees by improving the management of urban floral resources. We investigated the larval diet and distribution patterns of four solitary wild bee species with different diet specialization (i.e. Chelostoma florisomne , Osmia bicornis , Osmia cornuta and Hylaeus communis ) along urban intensity gradients in five European cities (Antwerp, Paris, Poznan, Tartu and Zurich) using two complementary analyses. Specifically, using trap‐nests and pollen metabarcoding techniques, we characterized the species' larval diet, assessed diet consistency across cities and modelled the distribution of wild bees using species distribution models (SDMs). Our results demonstrate that urban wild bees display different successful strategies to exploit existing urban floral resources: not only broad generalism (i.e. H. communis ) but also intermediate generalism, with some degree of diet conservatism at the plant family or genus level (i.e. O. cornuta and O. bicornis ), or even strict specialization on widely available urban pollen hosts (i.e. C. florisomne ). Furthermore, we detected important diet variation in H. communis , with a switch from an herbaceous pollen diet to a tree pollen diet with increasing urban intensity. Species distribution modelling indicated that wild bee distribution ranges inside urban ecosystems ultimately depend on their degree of specialization, and that broader diets result in less sensitivity to urban intensity. Policy implications . Satisfying larval dietary requirements is critical to preserving and enhancing wild bee distributions within urban gradients. For high to intermediate levels of feeding specialization, we found considerable consistency in the preferred plant families or genera across the studied cities, which could be generalized to other cities where these bees occur. Identifying larval floral preferences (e.g. using pollen metabarcoding) could be helpful for identifying key plant taxa and traits for bee survival and for improving strategies to develop bee‐friendly cities.

Urban areas often host exotic plant species, whether managed or spontaneous. These plants are suspected of affecting pollinator diversity and the structure of pollination networks. However, in dense cityscapes, exotic plants also provide additional flower resources during periods of scarcity, and the consequences for the seasonal dynamics of networks still need to be investigated. For two consecutive years, we monitored monthly plant-pollinator networks in 12 green spaces in Paris, France. We focused on seasonal variations in the availability and attractiveness of flower resources, comparing native and exotic plants at both the species and community levels. We also considered their respective contributions to network properties over time (specialization and nestedness). Exotic plants provided more abundant and diverse flower resources than native plants, especially from late summer on. However, native plants received more visits and attracted more pollinator species at the community level; and during certain times of the year at the species level as well. Exotic plants were involved in more generalist interactions, increasingly so over the seasons. In addition, they contributed more to network nestedness than native plants. These results show that exotic plants are major components of plant-pollinator interactions in a dense urban landscape, even though they are less attractive than natives. They constitute a core of generalist interactions that increase nestedness and can participate in the overall stability of the network. However, most exotic species were seldom visited by insects. Pollinator communities may benefit from including more native species when managing urban green spaces.

The contribution of urban greenspaces to support biodiversity and provide benefits for people is increasingly recognized. However, ongoing management practices favor vegetation oversimplification, often limiting greenspaces to lawns and tree canopy rather than multi-layered vegetation that includes under- and midstorey, and the use of nonnative species. These practices hinder the potential of greenspaces to sustain indigenous biodiversity, particularly for taxa like insects that rely on plants for food and habitat. Yet, little is known about which plant species may maximize positive outcomes for taxonomically and functionally diverse insect communities in greenspaces. Additionally, while cities are expected to experience high rates of introductions, quantitative assessments of the relative occupancy of indigenous vs. introduced insect species in greenspace are rare, hindering understanding of how management may promote indigenous biodiversity while limiting the establishment of introduced insects. Using a hierarchically replicated study design across 15 public parks, we recorded occurrence data from 552 insect species on 133 plant species, differing in planting design element (lawn, midstorey, and tree canopy), midstorey growth form (forbs, lilioids, graminoids, and shrubs) and origin (nonnative, native, and indigenous), to assess (1) the relative contributions of indigenous and introduced insect species and (2) which plant species sustained the highest number of indigenous insects. We found that the insect community was overwhelmingly composed of indigenous rather than introduced species. Our findings further highlight the core role of multi-layered vegetation in sustaining high insect biodiversity in urban areas, with indigenous midstorey and canopy representing key elements to maintain rich and functionally diverse indigenous insect communities. Intriguingly, graminoids supported the highest indigenous insect richness across all studied growth forms by plant origin groups. Our work highlights the opportunity presented by indigenous understory and midstorey plants, particularly indigenous graminoids, in our study area to promote indigenous insect biodiversity in urban greenspaces. Our study provides a blueprint and stimulus for architects, engineers, developers, designers, and planners to incorporate into their practice plant species palettes that foster a larger presence of indigenous over regionally native or nonnative plant species, while incorporating a broader mixture of midstorey growth forms.

Abstract Functional traits mediate the response of communities to disturbances (response traits) and their contribution to ecosystem functions (effect traits). To predict how anthropogenic disturbances influence ecosystem services requires a dual approach including both trait concepts. Here, we used a response–effect trait conceptual framework to understand how local and landscape features affect pollinator functional diversity and pollination services in apple orchards. We worked in 110 apple orchards across four European regions. Orchards differed in management practices. Low‐intensity (LI) orchards were certified organic or followed close‐to‐organic practices. High‐intensity (HI) orchards followed integrated pest management practices. Within each management type, orchards encompassed a range of local (flower diversity, agri‐environmental structures) and landscape features (orchard and pollinator‐friendly habitat cover). We measured pollinator visitation rates and calculated trait composition metrics based on 10 pollinator traits. We used initial fruit set as a measure of pollination service. Some pollinator traits (body size and hairiness) were negatively related to orchard cover and positively affected by pollinator‐friendly habitat cover. Bee functional diversity was lower in HI orchards and decreased with increased landscape orchard cover. Pollination service was not associated with any particular trait but increased with pollinator trait diversity in LI orchards. As a result, LI orchards with high pollinator trait diversity reached levels of pollination service similar to those of HI orchards. Synthesis and applications . Pollinator functional diversity enables pollinator communities to respond to agricultural intensification and to increase pollination function. Our results show that efforts to promote biodiversity provide greater returns in low‐intensity than in high‐intensity orchards. The fact that low‐intensity orchards with high pollinator functional diversity reach levels of pollination services similar to those of high‐intensity orchards provides a compelling argument for the conversion of high‐intensity into low‐intensity farms.

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.

The online version contains supplementary material available at 10.1007/s00035-024-00308-w.

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Abstract Loss of animal species and functional diversity can degrade ecosystem functions and services in plant–animal mutualistic networks, but their relative effects have rarely been previously examined in natural communities. Contrary to previously published theoretical results, under natural conditions, changes in pollinator functional niches caused by species and functional diversity losses are dynamic and often unpredictable. The lack of studies on natural networks limits our ability to predict future effects of decreasing pollinator diversity on wild and cultivated plants. We quantitatively evaluated the relative effects of pollinator species and functional diversity loss on plant–pollinator trait matching and pollination success across 40 spatiotemporally variable coastal networks. We found that low pollinator functional diversity (low abundance of long‐tongued pollinators) reduced community‐level plant functional specialization and trait matching between flowers and pollinators by reducing functional floral‐niche partitioning among pollinators. In contrast, pollinator species diversity did not influence community‐level trait matching. Furthermore, decreasing community‐level trait matching had a negative effect on community‐level plant pollination success, regardless of flower morphology. The present study demonstrated that pollinator functional diversity loss, rather than species diversity loss, was the main factor contributing to pollination functional loss in the plant–pollinator networks studied. We also demonstrated the importance of assessing functional aspects of plant–pollinator networks to evaluate community‐level pollination functional loss under global pollinator decline. Read the free Plain Language Summary for this article on the Journal blog.

People in urban and rural areas are planting habitat patches for pollinators in response to growing public awareness of the risks of pollinator declines; yet research rarely has been undertaken to inform the composition of such patches. Determining which key functional plant traits to prioritize and how plant-pollinator interaction dynamics operate in these small-scale, fragmented patches is critical to ensuring the efficacy of pollinator restoration efforts across landscapes. We established small-scale (2.5 m diameter) experimental patches and manipulated plant diversity and resource level (nectar) to determine the effects on pollinator abundance, pollinator diversity, and plant-pollinator facilitation-competition dynamics. Our results showed that in small-scale habitat, plant diversity and resource availability significantly affected the abundance and diversity of pollinating insects. Specifically, the treatments that contained high-resource plant species increased pollinator abundance and diversity the most. Plant diversity increased pollinator diversity and abundance only in the absence of high-resource plants. Pollination facilitation was observed in high-resource treatments, but varied among plant species. Competition for pollinators was observed in high-diversity treatments but did not affect seed set for high-resource plants in any of the treatments. Our results suggest that managers or landowners planting small-scale pollinator habitat should prioritize including species with high nectar production, and secondarily, a diverse mix of species if space and resources allow. The protocols we used to monitor pollinators can be used by community science observers with limited training, expanding the potential for assessment of future pollinator habitat restoration projects. Shared research identifying features critical to effective restoration will help conserve plant-pollinator mutualisms across landscapes.

Changes in climate and land use are major threats to pollinating insects, an essential functional group. Here, we unravel the largely unknown interactive effects of both threats on seven pollinator taxa using a multiscale space-for-time approach across large climate and land-use gradients in a temperate region. Pollinator community composition, regional gamma diversity, and community dissimilarity (beta diversity) of pollinator taxa were shaped by climate-land-use interactions, while local alpha diversity was solely explained by their additive effects. Pollinator diversity increased with reduced land-use intensity (forest < grassland < arable land < urban) and high flowering-plant diversity at different spatial scales, and higher temperatures homogenized pollinator communities across regions. Our study reveals declines in pollinator diversity with land-use intensity at multiple spatial scales and regional community homogenization in warmer and drier climates. Management options at several scales are highlighted to mitigate impacts of climate change on pollinators and their ecosystem services.

The environmental filtering of species traits can influence the identity of their interaction partners and the contribution of species interactions to ecosystem functioning, but the extent to which this process is influenced by landscape composition and configuration remains unclear. We combined a field experiment with an agent‐based model to assess how landscape structure and local flower patch isolation affect pollinator body‐size distribution and plant–pollinator interactions, sampled at different spatial extents. We then evaluated how these changes in pollinator functional (i.e. body‐size) diversity influence plant reproduction. We observed higher pollinator functional diversity in less‐isolated patches, which promoted plant reproduction via a relationship between functional diversity and interaction complementarity. This complementarity occurred partly because larger pollinators interacted with more plant species. Moreover, we showed that patch configuration at the landscape level can change the direction of these local‐scale patch isolation effects on pollinator body‐size distribution, functional diversity and plant–pollinator interactions. Importantly, these relationships were robust to sampling spatial extent. Thus, management strategies to promote pollination should account for local resources and landscape structure, because response, effect and interaction traits like body size connect landscape filtering effects with local community responses and outcomes of interaction‐based functions.

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Complex socio-economic, political and demographic factors have driven the increased conversion of Europe's semi-natural grasslands to intensive pastures. This trend is particularly strong in some of the most biodiverse regions of the continent, such as Central and Eastern Europe. Intensive grazing is known to decrease species diversity and alter the composition of plant and insect communities. Comparatively little is known, however, about how intensive grazing influences plant functional traits related to pollination and the structure of plant-pollinator interactions. In traditional hay meadows and intensive pastures in Central Europe, we contrasted the taxonomic and functional group diversity and composition, the structure of plant-pollinator interactions and the roles of individual species in networks. We found mostly lower taxonomic and functional diversity of plants and insects in intensive pastures, as well as strong compositional differences among the two grassland management types. Intensive pastures were dominated by a single plant with a specialized flower structure that is only accessible to a few pollinator groups. As a result, intensive pastures have lower diversity and specificity of interactions, higher amount of resource overlap, more uniform interaction strength and lower network modularity. These findings stand in contrast to studies in which plants with more generalized flower traits dominated pastures. Our results thus highlight the importance of the functional traits of dominant species in mediating the consequences of intensive pasture management on plant-pollinator networks. These findings could further contribute to strategies aimed at mitigating the impact of intensive grazing on plant and pollinator communities.

• Floral variables are the most important predictors of the pollinators. • Agroecological farming may reduce effect of urbanisation. • Urban gardens provide necessary resources for pollinators. • Value of urban nature reserves is high for populations of specialized insect species. Small African urban areas are composed of an urban core, farms, and natural areas. This mosaic has high potential for providing refuge for urban biodiversity, especially for beneficial groups like insect pollinators. Insect pollinators are important for agricultural yield, yet are in decline in many parts of the world. However, to date, African urban areas as a refuge for these pollinators are poorly explored, despite increasing urbanization and agricultural intensification in recent decades. Here, we investigate how insect pollinator diversity differs between gardens, agricultural areas, and natural areas in a southern African urban mosaic. We also explore the influence of urban green spaces on the taxonomic diversity of insect pollinators. Direct observation and pan traps were used for assessing the diversity of pollinators, and we measured associated environmental, floral, and landscape variables. Results indicated similar pollinator diversity between agricultural and natural areas for some taxa, and between agricultural areas and the urban gardens for other taxa. Significantly, floral variables were the most important predictors of the pollinators, with the enhancement of floral diversity ameliorating the effects of urbanization and agricultural intensification. In contrast, landscape context was less important, although significant, for insect pollinators in these mosaics. Results, although varying significantly among taxa, suggest that agroecological farming may serve as a buffer from the effects of urbanization for natural areas and reduce the effect of urbanization on pollinators in urban gardens by providing the necessary resources. Here, we show that floral variables are important for improving urban green planning. This could be achieved by the establishment of more flowering plants, especially in human-modified areas such as semi-urban agricultural areas and urban gardens.

Land-use change is having a negative effect on pollinator communities, and these changes in community structure may have unexpected impacts on the functional composition of those communities. Such changes in functional composition may impact the capacity of these assemblages to deliver pollination services, affecting the reproduction of native and wild plants. However, elucidating those relationships requires studies in multiple spatial scales because effects and consequences are different considering biological groups and interactions. In that sense, by using a multi-trait approach, we evaluated whether the landscape structure and/or local environmental characteristics could explain the functional richness, divergence, and dispersion of bee communities in agroecosystems. In addition, we investigated to what extent this approach helps to predict effects on pollination services. This study was conducted in an agroecosystem situated in the Chapada Diamantina region, State of Bahia, Brazil. Bees were collected using two complementary techniques in 27 sample units. They were classified according to their response traits (e.g., body size, nesting location) and effect traits (e.g., means of pollen transportation, specialty in obtaining resources). The Akaike information criterion was used to select the best models created through the additive combination of landscape descriptors (landscape diversity, mean patch shape, and local vegetation structure) at the local, proximal, and broad landscape levels. Our results indicate that both landscape heterogeneity and configuration matter in explaining the three properties of bee functional diversity. We indicate that functional diversity is positively correlated with compositional and configurational heterogeneity. These results suggest that landscape and local scale management to promote functional diversity in pollinator communities may be an effective mechanism for supporting increased pollination services.

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How pollinators mediate microbiome assembly in the anthosphere is a major unresolved question of theoretical and applied importance in the face of anthropogenic disturbance. We addressed this question by linking visitation of diverse pollinator functional groups (bees, wasps, flies, butterflies, beetles, true bugs and other taxa) to the key properties of the floral microbiome (microbial α- and β-diversity and microbial network) under agrochemical disturbance, using a field experiment of bactericide and fungicide treatments on cultivated strawberries that differ in flower abundance. Structural equation modelling was used to link agrochemical disturbance and flower abundance to pollinator visitation to floral microbiome properties. Our results revealed that (i) pollinator visitation influenced the α- and β-diversity and network centrality of the floral microbiome, with different pollinator functional groups affecting different microbiome properties; (ii) flower abundance influenced the floral microbiome both directly by governing the source pool of microbes and indirectly by enhancing pollinator visitation; and (iii) agrochemical disturbance affected the floral microbiome primarily directly by fungicide, and less so indirectly via pollinator visitation. These findings improve the mechanistic understanding of floral microbiome assembly, and may be generalizable to many other plants that are visited by diverse insect pollinators in natural and managed ecosystems.

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Declines in invertebrate biodiversity¹^,² pose a significant threat to key ecosystem services.^3-5 Current analyses of biodiversity often focus on taxonomic diversity (e.g., species richness),⁶^,⁷ which does not account for the functional role of a species. Functional diversity of species' morphological or behavioral traits is likely more relevant to ecosystem service delivery than taxonomic diversity, as functional diversity has been found to be a key driver of a number of ecosystem services including decomposition and pollination.^8-12 At present, we lack a good understanding of long-term and large-scale changes in functional diversity, which limits our capacity to determine the vulnerability of key ecosystem services with ongoing biodiversity change. Here we derive trends in functional diversity and taxonomic diversity over a 45-year period across Great Britain for species supporting freshwater aquatic functions, pollination, natural pest control, and agricultural pests (a disservice). Species supporting aquatic functions showed a synchronous collapse and recovery in functional and taxonomic diversity. In contrast, pollinators showed an increase in taxonomic diversity, but a decline and recovery in functional diversity. Pest control agents and pests showed greater stability in functional diversity over the assessment period. We also found that functional diversity could appear stable or show patterns of recovery, despite ongoing changes in the composition of traits among species. Our results suggest that invertebrate assemblages can show considerable variability in their functional structure over time at a national scale, which provides an important step in determining the long-term vulnerability of key ecosystem services with ongoing biodiversity change.

ABSTRACT The impact of land use changes on pollinator diversity can vary depending on factors such as the size of remaining natural habitat patches, the type and intensity of anthropogenic activities, and the functional composition of pollinator communities. This understanding is particularly crucial for mangrove ecosystems, which are critically endangered by human activities and prioritized in global conservation strategies. This study investigates how anthropization affects mangrove pollinator diversity by examining how pollinators with different functional traits respond to variations in mangrove patch size and anthropogenic changes in the surrounding landscape matrix. We found that overall pollinator abundance, richness, and diversity increased in smaller mangrove patches, potentially helping to mitigate negative effects such as inbreeding and genetic drift—common in naturally patchy and isolated mangrove populations. However, these pollinator metrics declined with increasing landscape anthropization, with notably lower values in urbanized landscapes compared to agricultural ones, despite the smaller patch sizes in more anthropized settings. This negative trend was consistent across pollinators with varying traits, though the magnitude of the effect differed among pollinator groups. Ground‐nesting and exposed‐nesting pollinators were most influenced by patch size, while lepidopterans and wasps, as well as species with either very small or large body sizes, solitary behavior, and nesting in exposed sites or cavities, were most affected by landscape anthropization. Conservation and management efforts should prioritize habitat provisioning for these most impacted groups to support mangrove ecosystem resilience.

Urban gardens can support diverse bee communities through resource provision in resource poor environments. Yet the effects of local habitat and landscape factors on wild bee communities in cities is still insufficiently understood, nor is how this information could be applied to urban wildlife conservation. Here we investigate how taxonomic and functional diversity of wild bees and their traits in urban community gardens are related to garden factors and surrounding landscape factors (e.g., plant diversity, amount of bare ground, amount of nesting resources, amount of landscape imperviousness). Using active and passive methods in 18 community gardens in Berlin, Germany, we documented 26 genera and 102 species of bees. We found that higher plant species richness and plant diversity as well as higher amounts of deadwood in gardens leads to higher numbers of wild bee species and bee (functional) diversity. Furthermore, higher landscape imperviousness surrounding gardens correlates with more cavity nesting bees, whereas a higher amount of bare ground correlates with more ground-nesting bees. Pollen specialization was positively associated with plant diversity, but no factors strongly predicted the proportion of endangered bees. Our results suggest that, aside from foraging resources, nesting resources should be implemented in management for more pollinator-friendly gardens. If designed and managed using such evidence-based strategies, urban gardens can create valuable foraging and nesting habitats for taxonomically and functionally diverse bee communities in cities.

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Even though urban green spaces may host a relatively high diversity of wild bees, urban environments impact the pollinator taxonomic and functional diversity in a way that is still misunderstood. Here, we provide an assessment of the taxonomic and functional composition of pollinator assemblages and their response to urbanization in the Paris region (France). We performed a spring-to-fall survey of insect pollinators in green spaces embedded in a dense urban matrix and in rural grasslands, using a plant setup standardized across sites and throughout the seasons. We compared pollinator species composition and the occurrence of bee functional traits over the two habitats. There was no difference in species richness between habitats, though urban assemblages were dominated by very abundant generalist species and displayed a lower evenness. They also included fewer brood parasitic, solitary or ground-nesting bees. Overall, bees tended to be larger in the city than in the semi-natural grasslands, and this trait exhibited seasonal variations. The urban environment filters out some life history traits of insect pollinators and alters their seasonal patterns, likely as a result of the fragmentation and scarcity of feeding and nesting resources. This could have repercussions on pollination networks and the efficiency of the pollination function.

Urbanization poses a major threat to biodiversity and food security, as expanding cities, especially in the Global South, increasingly compete with natural and agricultural lands. However, the impact of urban expansion on agricultural biodiversity in tropical regions is overlooked. Here we assess how urbanization affects the functional response of farmland bees, the most important pollinators for crop production. We sampled bees across three seasons in 36 conventional vegetable-producing farms spread along an urbanization gradient in Bengaluru, an Indian megacity. We investigated how landscape and local environmental drivers affected different functional traits (sociality, nesting behavior, body size, and specialization) and functional diversity (functional dispersion) of bee communities. We found that the functional responses to urbanization were trait specific with more positive than negative effects of gray area (sealed surfaces and buildings) on species richness, functional diversity, and abundance of most functional groups. As expected, larger, solitary, cavity-nesting, and, surprisingly, specialist bees benefited from urbanization. In contrast to temperate cities, the abundance of ground nesters increased in urban areas, presumably because larger patches of bare soil were still available beside roads and buildings. However, overall bee abundance and the abundance of social bees (85% of all bees) decreased with urbanization, threatening crop pollination. Crop diversity promotes taxonomic and functional diversity of bee communities. Locally, flower resources promote the abundance of all functional groups, and natural vegetation can maintain diverse pollinator communities throughout the year, especially during the noncropping season. However, exotic plants decrease functional diversity and bee specialization. To safeguard bees and their pollination services in urban farms, we recommend (1) preserving seminatural vegetation (hedges) around cropping fields to provide nesting opportunities for aboveground nesters, (2) promoting farm-level crop diversification of beneficial crops (e.g., pulses, vegetables, and spices), (3) maintaining native natural vegetation along field margins, and (4) controlling and removing invasive exotic plants that disrupt native plant-pollinator interactions. Overall, our results suggest that urban agriculture can maintain functionally diverse bee communities and, if managed in a sustainable manner, be used to develop win-win solutions for biodiversity conservation of pollinators and food security in and around cities.

Protected areas are a key conservation tool, yet their effectiveness at maintaining biodiversity through time is rarely quantified. Here, we assess protected area effectiveness across sampled portions of Great Britain (primarily England) using regionalized (protected vs unprotected areas) Bayesian occupancy-detection models for 1238 invertebrate species at 1 km resolution, based on ~1 million occurrence records between 1990 and 2018. We quantified species richness, species trends, and compositional change (temporal beta diversity; decomposed into losses and gains). We report results overall, for two functional groups (pollinators and predators), and for rare and common species. Whilst we found that protected areas have 15 % more species on average than unprotected ones, declines in occupancy are of similar magnitude and species composition has changed 27 % across protected and unprotected areas, with losses dominating gains. Pollinators have suffered particularly severe declines. Still, protected areas are colonized by more locally-novel pollinator species than unprotected areas, suggesting that they might act as ‘landing pads’ for range-shifting pollinators. We find almost double the number of rare species in protected areas (although rare species trends are similar in protected and unprotected areas); whereas we uncover disproportionately steep declines for common species within protected areas. Our results highlight strong invertebrate reorganization and loss across both protected and unprotected areas. We therefore call for more effective protected areas, in combination with wider action, to bend the curve of biodiversity loss – where we provide a toolkit to quantify effectiveness. We must grasp the opportunity to effectively conserve biodiversity through time.

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Abstract Managing agricultural environments in a way that maximises the provision of multiple ecosystem services is a significant challenge in the development of sustainable and secure food systems. Advances in network ecology provide a way forward, particularly in arable landscapes, as they incorporate mutualistic and antagonistic interactions associated with crop production. Here, we present an approach to identify mixes of non‐crop plant species that provide multiple ecosystem services while minimising disservices. Genetic algorithms were applied to the Norwood Farm ecological network—a comprehensive dataset of antagonistic and mutualistic species interactions on an organic farm in the United Kingdom. We aimed to show how network analyses can be used to select plants supporting a high diversity of insect pollinators and parasitoids of insect pests, but low diversity of herbivores. Further to this, we wanted to understand the trade‐offs in ecosystem service provision associated with conventional management practices that focus on individual ecosystem services. We show that multilayer network analyses can be used to identify mixes of plant species that maximise the species richness of pollinators and parasitoids (natural enemies of insect pests), while minimising the species richness of herbivores. Trade‐offs between ecosystem processes were apparent with several plant species associated with a high species richness of both positive (pollinators and parasitoids) and negative (herbivores) functional taxonomic groups. As a result, optimal plant species mixes for individual ecosystem services were different from the mix simultaneously maximising pollination and parasitism of pest insects, while minimising herbivory. Synthesis and applications . Plant mixes designed solely for maximising pollinator species richness are not optimal for the provision of other ecosystem services and disservices (e.g. parasitism of insect pests and herbivory). The method presented here will allow for the design of management strategies that facilitate the provision of multiple ecosystem services. To this end, we provide a protocol for practitioners to develop their own plant mixes suitable for farm‐scale management. This avenue of predictive network ecology has the potential to enhance agricultural management, supporting high levels of biodiversity and food production by manipulating ecological networks in specific ways.