Recreational trails as conduits for non-native plant invasions in mountain regions: Examples from around the globe

BARROS AGUSTINA; JONAS LEMBRECHTS; ANIBAL PAUCHARD; ALISA ALVAREZ; LISA REW; TIM SEIPEL; SHENGWEI ZONG; JANA MULLEROVA

formato virtual

Conferencia; International Association for Society and Natural Resources (IASNR) Conference 2021. Building a Global Network for Natural Resource Social Science; 2022

The International Association for Society and Natural Resources (IASNR)

Mountain ecosystems are of high conservation value and popular for hiking. While hiking trails provide benefits to human health and wellbeing, they can also have negative impacts. This includes favoring the establishment and spread of non-native plants, even into alpine environments. To address this, the research network MIREN (www.mountaininvasions.org/) adapted a protocol to monitor patterns of non-native plants along elevation in mountain trails. Vegetation is recorded using T-shaped transects, placed alongside the trail and perpendicularly into the natural vegetation. The T-transects are placed at regular elevational intervals between the trailhead to the highest point of the trail, with a minimum of 10 sampling sites per trail. In total, 40 trails in seven regions including South America (Chile and Argentina), North America (United States), Europe (Norway, Czech Republic) and Asia (China) were recorded. Most of the trails surveyed expand from montane to alpine environments with an average elevational range of 900 meters. A total of 850 vascular species were recorded, of which 12% were non-native. The regions with greater proportion of non-natives were in Chile (20%) and Argentina (17%). In comparison, trails in Norway and Czech Republic had very few non-natives (3%). Regional analyses for Chile and Argentina showed that non-native species occurrence decreased with increasing elevation and increased closer to the trail and with livestock presence. Native plant communities either facilitated or restricted non-natives. In Argentina, shrubs positively affected non-natives suggesting the importance of facilitation at higher elevations. In Chile, tree cover limited non-natives. Our results show that while directional ecological filtering acts to select species occurrence in mountain trails, disturbance and biotic factors are also important in determining non-native success, highlighting the importance of developing guidelines to minimize trail disturbance.