Increased traffic volume threatens plant–pollinator interactions and plant reproductive success

Abstract Roads represent one of the most widespread forms of human infrastructure. Their presence, along with associated vehicle traffic, fragments ecosystems and disrupts plant–pollinator interactions. However, the precise mechanisms through which these disturbances cascade to reorganise plant–pollinator interaction networks and ultimately affect plant reproduction remain poorly understood. In this study, we investigated how traffic volume (low vs. high) affects plant–pollinator communities, interaction networks and plant reproductive success along spatial gradients extending from roads in alpine meadows of the Tibetan Plateau. Using piecewise structural equation modelling, we found that high traffic volume reduced flower richness, which subsequently lowered pollinator abundance and restructured interaction networks—characterised by decreased connectance, increased nestedness and heightened specialisation—ultimately leading to lower community‐level plant reproductive success. These adverse impacts diminished with increasing distance from roads, suggesting a spatial buffering effect in roadside ecosystems. Synthesis . Our findings demonstrate that high traffic volume triggers cascading effects that disrupt mutualistic networks and undermine pollination services in fragile ecosystems. To conserve biodiversity and sustain ecosystem resilience, it is essential to incorporate pollination dynamics into roadside management. Practical measures such as establishing vegetative buffer zones and actively enhancing floral resources should be prioritised across existing and expanding road networks.