Bryophyte Inventory at Shenandoah National Park 2023-2025 - Open Format Dataset

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 248 species, four of which were rare at the global or state level, and 77 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 nor 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.

本研究于美国弗吉尼亚州仙纳度国家公园的36个样地（涵盖瀑布、河流、湿地或岩石露头生境）开展苔藓植物（bryophyte）群落调查，旨在明确稀有苔藓植物的分布位置，并探究人类干扰是否会对苔藓植物群落产生负面影响。研究人员系统性遍历全部36个样地，以收集并记录所有特有物种。此外，针对其中16个样地（8个水景生境样地、8个不同人类干扰程度的岩石露头样地），研究人员设置重叠样带，以计算各苔藓植物物种的盖度。本研究共记录到248个苔藓植物物种，其中4个为全球或州级稀有物种，另有77个物种为该公园历史标本与记录中未记载的新记录物种。研究发现，游客到访强度（即干扰等级）并未对两种生境类型下的苔藓植物多样性及盖度百分比产生显著影响。但受干扰与未受干扰样地的苔藓植物群落相异度较高，且两类样地在岩石露头生境与水景生境中均各自独立聚类。这表明人类干扰会影响苔藓植物群落组成；不过，受干扰与未受干扰样地的特有物种数量及其丰度并无差异。这一现象的成因可能是部分物种可耐受干扰，人类踩踏或可为耐干扰物种创造生存空间——这类物种相较于原本同生态位的干扰敏感物种，面临的种间竞争更少。公园内应将苔藓植物生物多样性保护工作聚焦于低干扰样地及栖息有稀有物种的样地，以确保干扰敏感物种与稀有物种的栖息地免受人类踩踏破坏。