Session

Plant–pollinator interactions in urban semi-natural grasslands are ideal subjects for investigating anthropogenic activities as drivers of ecological network decline in terms of diversity and functionality. Pollinators are vulnerable to anthropogenic disturbance as evidenced by the decreasing richness observed in many urban grasslands globally. Reduced flower and pollinator richness is expected to facilitate network downsizing and generalization, which may diminish pollination functions. To test the hypothesis, we examined the structure of 30 plant–pollinator networks and the pollination success of 12 native plant species in urban–rural paddy grasslands in an East-Asian megacity area. Pollination networks of more urbanized grasslands were significantly smaller and more generalized than those of rural grasslands. Community-wide pollination success was influenced by the degree of surrounding urbanization, network generalization and non-native flowers. The results generally support the hypothesis but suggest some positive effects of generalized urban networks on pollination services for native plants.