DOI: 10.5061/dryad.5qfttdzcv
title: Plant-pollinator interactions in Mediterranean semiarid ecosystems

description: Pollinators are fundamental for plant reproduction in natural and
 agricultural ecosystems. However, their populations are declining
 worldwide, threatening the functioning of the ecosystem service they
 provide. The factors driving this change are manifold, but land use
 changes and interspecific transmission of pathogens between managed and
 wild bees are prominent. In this context, most research efforts have
 focused on specific taxa and rarely at the community level, limiting our
 ability to fully understand the effects of global change on the
 functioning of plant-pollinator interactions in ecosystems. Here, we
 investigate the impact of human activities (beekeeping and land use
 intensity) on the spread of an emergent pathogen (Vairimorpha ceranae) in
 Mediterranean wild bee communities inhabiting landscapes with varying
 levels of anthropogenic disturbance. Plant-pollinator interactions were
 sampled in nine one-hectare plots along a gradient of land use (urban
 structures, croplands and natural vegetation) and beekeeping intensity. We
 analised the impact of human disturbances on pollination networks and
 pathogen prevalence and applied a network approach to examine whether
 total effects of species in networks (i.e. direct plus indirect
 interactions) explain pathogen spread through bee communities. We found
 that V. ceranae prevalence in honey bees is not a good predictor of the
 pathogen spread through bee communities. There seems to be a temporal
 mismatch between pathogen dynamics in managed and wild bees. Networks with
 more diversity of interactions and more plants showed less pathogen
 prevalence, but total effect analyses (i.e. combining direct and indirect
 interactions) failed to explain pathogen transmission across pollination
 networks. Croplands increased wild bee density, and interactions and
 species diversity in networks while shrublands had the opposite effect.
 Our results highlight the importance of studying pathogen dynamics at the
 community level and analysing species interaction patterns to improve our
 understanding of pathogen spread through communities.
description: # Plant-pollinator interactions in Mediterranean semiarid ecosystems
 Data on the manuscript
 "Contrasting effects of beekeeping and land use on plant-pollinator
 networks and pathogen prevalence in Mediterranean semiarid
 ecosystems" (. Data on
 collected bees and plant-pollinator interactions, matrices of
 inteteractions between plants and bees in the study plots, prevalence of
 Vairimorpha ceranae and collected variables (densities of honey bees and
 wild bees, number of flowering plant species, etc). ## Description of the
 data and file structure Table S1. It shows the information on the sampled
 bee individuals, the plants where they were foraging and the sampling date
 and location Table S2. It includes the matrices of interactions between
 bees and plants per study plot. Data derived from Table S1. Table S3.
 Prevalence of *Vairimorpha ceranae* in the collected bees (i.e. number of
 bees with the pathogen/total bees collected) per sampled plot. Prevalence
 of V. ceranae in the plants visited by the bees (i.e. dividing the number
 of visits received by bees positive to the pathogen between the total
 number of visits, excluding the visits realized by the honey bee). Table
 S4. Collected variables: (i) sampling; (ii) unit (i.e. sampled plot);
 (iii) latitude of the sampled plot; (iv) longitude of the sampled plot;
 (v) density of honey bees in the plots (bees/m2); (vi) density of wild
 bees (bees/m2); (vii) Prevalence of *Vairimorpha ceranae* in honey bees;
 (viii) Prevalence of *V. ceranae* in wild bees; (ix) number of bee
 species; (x) nº of flowers in the plots; (xi) density of flowers
 (flowers/m2); (xii) number of plant species registered. ## ##