The Impact of Hiking Trails and Storm Distribution on Plant Diversity

Abstract

Non-native species are a major threat to biodiversity and its associated ecosystem services. Hiking trails act as corridors for non-native plant introductions by recreationists. Removal of vegetation along trails creates areas of disturbance that form open niches and can subsequently foster the establishment of non-native species, which may result in biotic homogenization and reduction in native species richness. Therefore, my study collected species richness and abundance data for vascular plants in plots along three recently storm-damaged hiking trails in Sleeping Giant State Park( Hamden, Connecticut)to better understand ho w hiking trails and disturbances impact plant biodiversity. I used pre-and post-storm Google Earth Pro images and land cover data from the National Land Cover Database (NLCD)to measure forest loss from the 2018 tornado. I then recorded species identification, life for m, abundance, trail proximity, elevation, distance from trailhead, and the presence/absence of storm disturbance for each quadrat and used a general linear model with Poisson distribution to deter mine differences for each response variable, followed by back wards selection to determine the most parsimonious model. Alpha (Shannon’s) and beta (Jaccard, Bray-Curtis, and Morisi ta-Horn)indices were used to evaluate the effect of trail proximity, storm disturbance, distance from trailhead, and elevation using Adonis. Finally, relative rank abundance data for total and non-tree species were evaluated for trail proximity. Trail proximity and distance from trailhead were the two explanatory variables for total and native species richness. Trailside plots had fewer mature trees but more non-natives, graminoids and forbs, potentially responding to the additional niche spaces from the disturbance caused by trailside development and maintenance. Alpha and beta diversity did not differ with any of the tested variables. Rank abundance curves indicated that trailside plots were dominated by sedges, tree seedlings and herbaceous perennials, while interior plots had more established vegetation. Non-native plants were relatively low and had no ho mogenizing effect, yet this result may be attributed to current park management practices. Therefore, park staff should continue to monitor and control non-native plants by focusing on areas adjacent to trails and adopting maintenance practices that encourage the growth of native species.