Inventory of Rare Bryophytes to Inform High-Use Recreation Site Management in Shenandoah National Park

Shershen, Eric; Mazzatta, Aspen; Cass, Wendy; Paull, Stephen; Budke, Jessica

doi:10.36967/2317489

We surveyed bryophyte communities at 36 sites containing either waterfalls, rivers, wetlands, or rock outcrops in Shenandoah National Park in Virginia to determine the location and distribution of rare bryophytes and to explore whether human disturbance negatively impacted bryophyte communities. An intentional meander through the 36 sites was conducted to collect and document all unique species. In addition, we examined overlapping transect lines to calculate species level bryophyte cover at 16 of the sites, eight containing water features and eight with rock outcrops with varying levels of human disturbance. We found 247 species, three of which were rare at the global or state level, one that was a new state record for Virginia, and 76 of which were new to the park compared to historical specimens and records from the park. We found that visitation intensity (level of disturbance) did not significantly impact bryophyte diversity or percent cover at either site type. However, we observed high levels of bryophyte community dissimilarity between disturbed and undisturbed sites, and these sites clustered independently from one another in both rock outcrops and water feature sites. This suggests that human disturbance impacts the bryophyte community composition; however, the number of unique species and their abundance is not different between disturbed and undisturbed sites. This may be because some species can tolerate disturbances, and human foot traffic may create opportunities for more disturbance-resilient species to occupy the space, as these species face less competition from disturbance-sensitive species that typically share the same niche. Investment in the preservation of bryophyte biodiversity within the park should be targeted towards sites with low levels of disturbance and those housing rare species, to ensure disturbance-sensitive and rare species’ habitat is protected from human trampling damage.

Inventory of Rare Bryophytes to Inform High-Use Recreation Site Management in Shenandoah National Park

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