Mixed effects of urbanization on pollination services among four native plant species

Urban Farm DB summary

This study measured pollination services across gradients of within-city urbanization and urban green space fragmentation at 10 community gardens in the United States, deploying four native indicator (phytometer) plant species and measuring visitor rate and alpha-diversity in relation to each species' reproductive outcomes. Although the researchers predicted a negative effect of urbanization, they found limited evidence of decline; contrary to expectation, Lobelia siphilitica showed increased visitor alpha-diversity and higher seed mass in more urbanized gardens, fragmentation effects were mixed -- edge density correlated positively with one species and negatively with another -- and local garden floral richness showed no influence, likely because richness was uniformly high across gardens.