Hiking trails shift plant species' realized climatic niches and locally increase species richness

Aim The presence and use of trails may change plant species' realized climatic niches via modified abiotic biotic conditions including propagule transport, allowing competition-pressed alpine species to expand their rear edges towards warmer locations lowland extend leading cooler locations. We investigated whether mountain indeed act as corridors for colonization shift niches, resulting in higher richness trailsides. Location Dovrefjell Abisko area the Scandes mountains Norway Sweden. Methods surveyed community composition disturbances along 16 hiking summer 2018 (Dovrefjell) 2019 (Abisko). linked changes optimum variation climate, trail effects resident characteristics. Results Plant was on average 24% greater trailside than interior vegetation plots. Proximity accounted 9% harshness 55% explained our model. Trailsides increased richness, especially relatively species-poor sites close introduction points (each accounting model gains). Shifts optima related undisturbed optimum, with being more likely move into While some disturbance-associated shifted colder locations, contrary expectations this not case species. Overall, shifts resulted overlapping trailsides vegetation. Main conclusion Trails can locally increase by creating opportunities colonizing weaker competitors. Because prevailing disturbance, they even provide persistence downward expansion species, aiding conservation efforts.