DOI: 10.5061/dryad.b8gtht7r4
title: Mixed effects of urbanization on pollination services among four native plant species

description: The pollination services provided by insects maintain ecosystem
 functioning and services in urban green spaces. Most research investigates
 rural to urban gradients, where it is found that pollination services are
 often greater in urban green spaces than in rural counterparts. However,
 as urbanization intensifies, the extent to which pollination services are
 maintained as urban green spaces are replaced and become increasingly
 fragmented requires further research. The purpose of this study was to
 examine pollination services across gradients of within-city urbanization,
 urban green space fragmentation, and local floral richness. We deployed
 four plant indicator (phytometer) species across ten community gardens
 that varied in urban cover and urban green space edge density. We measured
 visitor rate and α-diversity and related these factors to plant
 reproductive outcome for each phytometer species. While we predicted a
 negative effect of urbanization, we found limited evidence that
 pollination services decline across the sampled within-city urbanization
 gradient. Contrary to our expectation, Lobelia siphilitica showed
 increased visitor α-diversity and higher mass per seed in more urbanized
 gardens, suggesting positive urbanization effects. Fragmentation effects
 were mixed, with edge density positively correlated with one of the four
 phytometer species and negatively correlated with another species. Local
 garden richness did not influence pollination services, likely due to
 uniformly high floral richness across gardens. Our findings suggest that
 in some cases, highly urbanized community gardens can not only maintain
 pollination services but also outperform less urbanized gardens. Both
 urbanization and fragmentation effects were highly species-specific,
 highlighting the need for further research on how landscape heterogeneity
 and plant traits interact to influence urban pollination services.
description: # Mixed effects of urbanization on pollination services among four native
 plant species Dataset DOI:
 [10.5061/dryad.b8gtht7r4](10.5061/dryad.b8gtht7r4) ## Description of the
 data and file structure This repo contains a CSV file.
 'data.csv' is data on pollinator abundance and diversity, as
 well as plant reproduction of four phytometer species that were deployed
 across ten sites varying in urban cover and edge density in the city of
 Toronto. This repo is supporting information for Sookhan N., Onuferko
 T.M., MacIvor J.S. 2025. Mixed effects of urbanization on pollination
 services among four native plant species ### Files and variables ####
 File: data.csv **Description:**  ##### Variables * site_id: Unique letter
 assigned to each of the ten sites (unitless) * urban_cover: Percentage of
 urban land cover within a 500 m buffer surrounding each site (%) *
 ugs_edge_density: Edge density of urban green space within a 500 m buffer
 surrounding each site (m/m^2^) * floral_richness_1: Count of the number of
 in-flower plant genera at each site completed between Jun 27 and Jun 30 of
 2019 (unitless)  * floral_richness_2: Count of the number of in-flower
 plant genera at each site completed between Aug 20 and Sep 9 of
 2019 (unitless) * floral_richness_3: Count of number of in flower plant
 genera at each site, completed on Oct 7 (unitless) *
 species_phytometer: Phytometer species for which pollinator and
 reproductive information correspond. 'PEHI' = Penstemon
 hirsutus, 'DECA' = Desmodium canadense, 'LOSI' =
 Lobelia siphilitica, 'SYNO' = Symphyotrichum novae-angliae *
 floral_units_array: Average number of floral units present in the deployed
 temporary flowering patch across timed observations (unitless) *
 number_of_visits: Total number of recorded pollinator visits pooled across
 all timed observation periods (unitless) * survey_effort: Total survey
 effort in minutes pooled across all timed observation periods (minutes) *
 qD_0: Rarified or extrapolated Hill number (q=0)/ species
 richness (unitless) * qD.LCL_0: Lower confidence interval of Hill number
 (q=0)/ species richness estimate (unitless) * qD.UCL_0: Upper confidence
 interval of Hill number (q=0)/ species richness estimate (unitless) *
 qD_2: Rarified or extrapolated Hill number (q=2)/ Simpson
 diversity (unitless) * qD.LCL_2: Lower confidence interval of Hill number
 (q=2)/ Simpson diversity estimate (unitless) * qD.UCL_2: Upper confidence
 interval of Hill number (q=2)/ Simpson diversity estimate (unitless) *
 mass_seed_mg: Average seed mass per fruit across all measured fruits (mg)
 * number_seed: Total number of seeds pooled across all measured fruits
 (unitless) * mass_per_seed_ug: Average mass per seed across all measured
 fruits (μg) * fruit_sample_size: Total number of measured fruits
 (unitless) ## Code/software N/A ## Access information N/A