Generalist pollinators are important in many habitats, but little research has been done on small-scale spatial variation in interactions between them and the plants that they visit. Here, using a spatially explicit approach, we examined whether multiple species of flowering plants occurring within a single meadow showed spatial structure in their generalist pollinator assemblages.We report the results for eight plant species for which at least 200 individual visits were recorded. We found that for all of these species, the proportions of their general pollinator assemblages accounted for by particular functional groups showed spatial heterogeneity at the scale of tens of metres. This heterogeneity was connected either with no or only subtle changes of vegetation and flowering species composition. In five of these species, differences in conspecific plant density influenced the pollinator communities (with greater dominance of main pollinators at low-conspecific plant densities). The density of heterospecific plant individuals influenced the pollinator spectrum in one case.Our results indicate that the picture of plant-pollinator interactions provided by averaging data within large plots may be misleading and that within-site spatial heterogeneity should be accounted for in terms of sampling effort allocation and analysis. Moreover, spatially structured plant-pollinator interactions may have important ecological and evolutionary consequences, especially for plant population biology.

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Background Foraging activities of wild boar ( Sus scrofa ) create small‐scale soil disturbances in many different vegetation types. Rooting alters species composition by opening niches for less‐competitive plants and, as a recurrent factor, becomes a part of the community disturbance regime. Vegetation responses to wild boar disturbance have mostly been studied in the boar's non‐native range or in native forest, rather than in open habitats in the native range. We investigate the response of open European semidry grassland vegetation dominated by Brachypodium pinnatum to native wild boar pressure in an abandoned agricultural landscape. Methods To describe the disturbance regime, we repeatedly mapped rooted patches during a 5‐year period. Additionally, to study the vegetation response, we performed an artificial disturbance experiment by creating 30 pairs of simulated disturbances and undisturbed plots. The vegetation composition of the paired plots was repeatedly sampled five times in eight years of the study. Results Based on repeated mapping of disturbances, we predict that if the disturbance regime we observed during the 5‐year period were maintained over the long term, it would yield a stable vegetation ratio consisting of 98.7% of the grassland undisturbed, 0.4% with fresh disturbance, and 0.9% in older successional stages. Vegetation composition in the artificially disturbed plots was continuously converging to that of undisturbed vegetation, but these disturbed plots still differed significantly in composition and had higher species number, even after eight years of succession. Synthesis Our results thus show that wild boar disturbance regime in its native range increases heterogeneity and species diversity of semidry grassland vegetation.

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