Classification of dwarf heath plant communities on the coastal barrens of Nova Scotia

Abstract

Nova Scotia’s coastal barrens are comprised predominantly of heathlands, a globally threatened community type. Coastal barrens provide habitat for a number of nationally rare species. Despite their ecological and cultural importance, Nova Scotia’s coastal barrens are poorly described. My objectives were to classify and describe coastal dwarf heath plant communities and to quantify environmental factors that explain variation in their composition, diversity, and distribution. I sampled plant species abundance alongside comprehensive environmental and soils data across Nova Scotia. Using ordinations and cluster analyses combined, I numerically classified three distinctive plant communities. I inventoried 253 species of vascular plants, bryophytes and lichens, including several species of conservation concern. Environmental variables with significant influence on heathland vegetation structure included: moisture regime, fetch distance, soil depth, elevation, distance from the coast, and slope gradient. Future conservation efforts should prioritize rare species and evaluate habitat representivity using these quantitative community definitions in place of current qualitative approaches.