Tom Wessels, MA
Department of Environmental Studies
The importance of cliff ecosystems to regional biodiversity has been over looked until recently. It is now understood that cliffs contain diverse communities of plants and animals, some of which are specific to them, which contribute to an area's biodiversity. A review of the literature found a majority of the research conducted on human induced cliff impacts were focused on cliff edges and bases. Due to potential impacts rock climbers may have on cliff ecosystems, research has been done to determine the significance of these impacts. Unfortunately, none of these studies have focused on the influence of climbing chalk on cliff communities. The interest sparked by Donnie MacGowan's project on the influence of rock climbing chalk on rock weathering, as well as the dismissive attitude I received form land managers and climbing organizations on the influence of climbing chalk, initiated this study to look at the influence the presence of chalk on cliff plant communities. By analyzing the coverage change of 13 cliff plant species using the Wilcoxon Rank test, it was discovered that moss (p=0.001), Lepraria lobificans (p=0.012), and Algae (p=0.028) were affected by the presence of chalk. A comparison of the change in coverage between the control (C) and experimental (E) group for these three species reveals the influence on moss (C = -0.5 ± 4.61 and E = -4.7 ± 7.06) and Lepraria lobificans (C = 4.8 ± 6.97 and E= -3.8 ± 8.37) were negative, while Algae (C = 1.0 ± 8.97 and E = 3.4 ± 5.79) was positive.