1. Theoretical models indicate that the structure of plant-pollinator networks has important implications for the reproduction and survival of species. However, despite the growing information on the mechanisms underlying such a structure, it is still difficult to predict the functional consequences of species' structural positions in these networks. From the plant perspective, species position and roles in pollination networks might be related to traits describing flower attractiveness, availability and dependence on pollinators. In turn, both network metrics and plant traits might influence plant species fitness.

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Understanding how pollination services can be maintained in increasingly anthropogenic landscapes is a current challenge for basic and applied ecology. The stability of plant-pollinator communities might increase in heterogeneous landscapes with a high diversity of species and alternative habitats, both through larger independent fluctuations of populations (portfolio effect) and increased species asynchrony. However, how the drivers of stability (portfolio effect and synchrony) vary along land-use gradients remains largely unknown. Using independent samplings for plants, pollinators and their interactions in Mediterranean communities along a gradient of landscape heterogeneity, we assessed the relationships between within-year stability and its drivers, and between the drivers of stability, landscape heterogeneity and species diversity. In addition, we evaluated the relationship between the stability of plant-pollinator interactions (temporal mean/SD of pairwise interactions) and the structure of mutualistic networks (modularity, nestedness, connectance). As expected, stability increased with larger portfolio effects and asynchronies. Interaction stability was positively related to pollinator stability, but not to plant stability. Landscape evenness increased the stability of plants, pollinators and their interactions, through increased portfolio effects. However, for plants and pollinators, the effect was detected at a smaller scale (1-km) than for interactions (2-km); and for pollinators and interactions, the effect was only evident from medium-to-high levels of landscape evenness. Temporal synchrony of species/pairwise interactions was an important driver of stability, tightly linked to species/interaction diversity. More asynchronous communities showed a larger portfolio effect and were also those with higher species evenness for all plants, pollinators and their interactions; while synchrony was also weakly positively related to species richness for plants. Interestingly, more modular mutualistic network structures conferred enhanced overall community stability, through higher portfolio effect and asynchrony. Preserving diverse communities within the heterogeneous Mediterranean landscapes may help maintain the stability of pollination services, both through effects on synchrony and the portfolio effect.

Loss of habitats and native species, introduction of invasive species, and changing climate regimes lead to the homogenization of landscapes and communities, affecting the availability of habitats and resources for economically important guilds, such as pollinators. Understanding how pollinators and their interactions vary along resource diversity gradients at different scales may help to determine their adaptability to the current diversity loss related to global change. We used data on 20 plant-pollinator communities along gradients of flower richness (local diversity) and landscape heterogeneity (landscape diversity) to understand how the diversity of resources at local and landscape scales affected (1) wild pollinator abundance and richness (accounting also for honey bee abundance), (2) the structure of plant-pollinator networks, (3) the proportion of actively selected interactions (those not occurring by neutral processes), and (4) pollinator diet breadth and species' specialization in networks. Wild pollinator abundance was higher overall in flower-rich and heterogeneous habitats, while wild pollinator richness increased with flower richness (more strongly for beetles and wild bees) and decreased with honeybee abundance.Network specialization (H 2 0 ), modularity, and functional complementarity were all positively related to floral richness and landscape heterogeneity, indicating niche segregation as the diversity of resources increases at both scales.Flower richness also increased the proportion of actively selected interactions (especially for wild bees and flies), whereas landscape heterogeneity had a weak negative effect on this variable. Overall, network-level metrics responded to larger landscape scales than pollinator-level metrics did. Higher floral richness resulted in a wider taxonomic and functional diet for all the study guilds, while functional diet increased mainly for beetles. Despite this, specialization in networks (d 0 ) increased with flower richness for all the study guilds, because pollinator species fed on a narrower subset of plants as communities became richer in species. Our study indicates that pollinators are able to adapt their

Seventy five percent of fruit production of the major global crops benefit from insect pollination. Hence, there has been increased interest in how global change drivers impact this critical ecosystem service. Because standardized data on crop pollination are rarely available, we are limited in our capacity to understand the variation in pollination benefits to crop yield, as well as to anticipate changes in this service, develop predictions, and inform management actions. Here, we present CropPol, a dynamic, open and global database on crop pollination. It contains measurements recorded from 189 crop studies, covering 3,216 field observations, 2,421 yield measurements (i.e. berry weight, number of fruits and kg per hectare, among others), and 46,262 insect records from 49 commercial crops distributed around the globe. CropPol comprises 32 of the 87 leading global crops and commodities that are pollinator dependent. Malus domestica is the most represented crop (25 studies), followed by Brassica napus (22 studies), Vaccinium corymbosum (13 studies), and Citrullus lanatus (12 studies). The most abundant pollinator guilds recorded are honey bees (33.12% counts), bumblebees (18.65%), flies other than Syrphidae and Bombyliidae (13.76%), other wild bees (13.51%), beetles (11.47%), Syrphidae (4.86%), and Bombyliidae (0.06%). Locations comprise 32 countries distributed among European (70 studies), Northern America (59), Latin America and the Caribbean (27), Asia (22), Oceania (10), and Africa (7). Sampling spans three decades and is concentrated on 2001-05 (21 studies), 2006-10 (38), 2011-15 (87), 2016-20 (40). This is the most comprehensive open global data set on measurements of crop flower visitors, crop pollinators and pollination to date and we encourage researchers to add more datasets to this database in the future. No copyright restrictions are associated with the use of this dataset. Please cite this data paper when the data are used in publications and cite individual studies when appropriate.

Las abejas son un grupo extremadamente diverso con más de 1000 especies descritas en la península ibérica. Además, son excelentes polinizadores y aportan numerosos servicios ecosistémicos fundamentales para la mayoría de ecosistemas terrestres. Debido a los diversos cambios ambientales inducidos por el ser humano, existen evidencias del declive de algunas de sus poblaciones para ciertas especies. Sin embargo, conocemos muy poco del estado de conservación de la mayoría de especies y de muchas de ellas ignoramos cuál es su distribución en la península ibérica. En este trabajo presentamos un esfuerzo colaborativo para crear una base de datos de ocurrencias de abejas que abarca la península ibérica e islas Baleares que permitirá resolver cuestiones como la distribución de las diferentes especies, preferencia de hábitat, fenología o tendencias históricas. En su versión actual, esta base de datos contiene un total de 87 684 registros de 923 especies recolectados entre 1830 y 2022, de los cuales un 87% presentan información georreferenciada. Para cada registro se incluye información relativa a la localidad de muestreo (89%), identificador y colector de la especie (64%), fecha de captura (54%) y planta donde se recolectó (20%). Creemos que esta base de datos es el punto de partida para conocer y conservar mejor la biodiversidad de abejas en la península ibérica e Islas Baleares. Se puede acceder a estos datos a través del siguiente enlace permanente: https://doi.org/10.5281/zenodo.6354502

Background and Aims The loss of natural habitats may strongly affect the fitness of plants that depend on animals for reproduction. However, still very little is known about the differential effects of habitat disturbance on the distinct phases of the reproductive cycle of plants, especially in non-rewarding species. Methods We assessed the effects of habitat disturbance on the entire reproductive cycle of Arum pictum ssp. sagittifolium, a species with deceptive pollination endemic to the western Mediterranean Basin. For this, we performed hand-pollination and bagging experiments, evaluated the role of pollinators and dispersers on reproduction, and estimated seedling recruitment in three natural and three disturbed populations (according to their surrounding natural habitat) in Mallorca Island. Key Results Pollinators were sphaerocerid flies (mainly Coproica, with ca. 50% of visits) and staphylinid beetles, and were required for sexual reproduction. Habitat disturbance affected differently the reproductive phases of A. pictum ssp. sagittifolium. Habitat disturbance did have a positive effect on Shannon pollinator diversity (but not on pollinator richness), and total pollinator and Coproica abundance were three times higher in disturbed habitats, where overall seed production was also ca. 30% higher in natural ones. Seed production increased with Coproica abundance, but only in natural habitats. Seed dispersers of A. pictum ssp. sagittifolium were birds, mainly Sylvia atricapilla. Although habitat disturbance did not influence disperser diversity or abundance, the majority of seedlings appeared under adult plants and in natural habitats. Conclusions Overall recruitment was higher in natural habitats, but this effect could have been masked by only assessing pollinator and disperser numbers, as processes related to the quality of these interactions might be influencing fitness. Our study highlights the need to study different reproductive phases and their multiple components and processes to properly understand the effects of habitat disturbance on the regeneration of plant populations.

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