Bryophytes of Mingan Archipelago National Park Reserve, Quebec: a boreal flora with arctic and alpine components

Abstract

The Mingan Archipelago National Park Reserve has a bryophyte flora of 302 species, including 233 mosses and 69 hepatics. This includes about 45% of the known bryoflora of the Gulf of St. Lawrence region. The park bryophyte flora is dominated by boreal species and has lesser representation of temperate and arctic-alpine species. About 73% of the park flora belongs to the boreal distributional element and two-thirds of these species are circumboreal or widespread in the boreal biome of the northern hemisphere. The flora is youthful and all species have colonized the islands within the last 7000 years. Most of the Mingan species probably originated from populations that survived during the last glaciation in sites south of the icesheet margin. However, many species could have migrated to the islands from nearby réfugia within the Gulf of St. Lawrence region where they were able to survive the glaciation in situ. These refugial species include many of the arctic-alpine and montane species found in the park. Key words: Mingan Islands, bryophytes, diversity, glaciation.