Multiscale habitat characterization of herbaceous Atlantic Coastal Plain Flora on lakeshores in Nova Scotia

Abstract

Atlantic Coastal Plain Flora (ACPF) are a group of plants mostly inhabiting lakeshores along the Atlantic coast of the United States, with disjunct populations in Nova Scotia and Ontario. To better define their ecological requirements, the main objective of this study was to determine the factors (biotic and abiotic habitat components) influencing ACPF communities (distribution, species abundance, and richness) at both the landscape and local scales. On 16 lakeshores in southwestern Nova Scotia, we characterized ACPF communities and habitat within 20 cm square contiguous quadrats distributed along 20 m transects (landscape scale) and in 5 m × 5 m grids (local scale). Performing redundancy analysis (n = 16 transects), we found that at the landscape scale, shoreline slope and shrub species distribution influenced the quantity of suitable habitat available for ACPF, with mineral shorelines supporting higher ACPF richness. Using spatial generalized linear mixed models (n = 3125 quadrats in five grids), we found that elevation, vegetation elements (shrubs, sundews, graminoids), and substrate type mostly influenced ACPF presence and abundance. ACPF also showed inter-specific differences in habitat preferences. Defining ACPF ecological requirements at both the landscape and local scales is important to guide conservation and management actions in Nova Scotia and throughout their North American range.