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

This study examines the impact of traffic volume (high vs. low) on plant-pollinator communities, interaction networks, and plant reproductive success in alpine meadows on the northeastern margin of the Tibetan Plateau. A total of 30 study sites were selected, with an equal distribution between road verges with high and low traffic volumes. For each site, three plots were established at varying distances from the road (0–10 m, 30–40 m, and 60–70 m). Within each plot, plant-pollinator interactions were surveyed across three transects, yielding a total of 135 hours of sampling. Ninety quantitative plant-pollinator networks were constructed, and key network metrics such as connectance, nestedness, and specialization (H2′)were assessed. Flower richness and abundance were evaluated using three randomly placed 1 m × 10 m quadrats per plot, while pollinator abundance and richness were determined by counting insect visitors and species per plot. Community-level plant reproductive success was measured for pollinator-dependent species. Seed numbers for each species were standardised using z-scores, and the mean reproductive success per plot was calculated. These data provide empirical insights into how traffic-induced disturbances shape plant-pollinator interactions, influencing the stability and functionality of pollination networks in roadside ecosystems.