Can Pavement Gaps in Coastal Roads Serve as Alternative Habitats for Sea Cliff Plants?

Abstract

This study examined the environmental factors that allow sea cliff plants to establish in pavement gaps along a coastal road in Matsumae, northern Japan. Vegetation surveys at 58 sites, combined with measurements of gap structure, soil properties, and physical environmental factors such as distances from sea cliffs (DC) and the shoreline (DS), were analyzed using generalized linear models. DC and DS were the strongest predictors of sea cliff species occurrence and dominance, with DS showing particularly steep declines. However, when pavement gaps were located close to the shoreline, sea cliff species were able to establish even at sites relatively distant from the cliffs themselves. Soil pH, electrical conductivity, and gap structure also influenced several species. These findings indicate that pavement gaps can function as secondary habitats for sea cliff species and highlight their potential value for conservation along coastal roads.