Going off trails: How dispersed visitor use affects alpine vegetation.

Area of Science:

• Ecology
• Conservation Biology
• Plant Community Ecology

Background:

• Mountain protected areas offer ecosystem services like biodiversity conservation and recreation.
• Off-trail tourism and pack animals can negatively impact sensitive alpine vegetation.

Purpose of the Study:

• To assess the impacts of off-trail disturbance on alpine steppe vegetation in Aconcagua Provincial Park, Argentina.
• To understand how varying levels of disturbance and abiotic factors affect plant communities.

Main Methods:

• Studied 91 plots (20 m²) in the Horcones Valley.
• Utilized generalized linear models and ordinations to analyze vegetation data.
• Assessed impacts of different disturbance levels and abiotic factors.

Main Results:

• Off-trail disturbance led to decreased cover of native plants, including the endemic shrub Adesmia aegiceras.
• Increased disturbance resulted in greater cover of non-native herbs like Convolvulus arvensis.
• Shift observed from stress-tolerant species to ruderal plants with acquisitive traits (shorter, higher Specific Leaf Area).

Conclusions:

• Off-trail trampling significantly alters alpine plant community structure.
• Trampling favors specific plant traits, impacting species composition.
• Restricting off-track use is vital for high-conservation-value mountain ecosystems.