Seeds in the City: regeneration strategies across urban species pools

Urban ecosystems support a substantial share of regional biodiversity and deliver key ecosystem services in densely populated landscapes. Seed regeneration is a critical process shaping urban plant communities, yet regeneration strategies remain poorly understood across the diversity of urban ecosystems. We assessed seed-based regeneration in a temperate coastal city by measuring plant traits, seed viability, and germination responses to temperature, light, and water stress in seven urban species pools associated with habitats differing in disturbance and stress context. Species belonging to pavement and park-lawn species pools showed low germination, whereas plants from roadside and meadow species pools exhibited high germination across stress treatments. Seed traits were weak predictors of germination performance, highlighting the importance of germination responses for regeneration in cities. Species with consistent germination under stress emerge as promising candidates for urban revegetation and ecological restoration. This study provides a regeneration-based framework to guide species selection and management of urban green spaces.