+ Trail Disturbance in the Alpine Meadow on Arapaho Pass and Mount Yale Marieta Bialek Vegetation Ecology 2013 Mountain Research Station University of Colorado at Boulder

+ Alpine Vegetation (above 3360m) Controls (USNVC) Snowmelt Wind Permafrost Short Growing Season Plants adapted to conserving moisture Disturbance factor: Hiking Trails. Trampling reduces density of vegetation and increases erosion. (Klug, Scharfetter-Lehrl, Scharfetter 2002 citing (Grabherr, 1985) Plants resistant to trampling include turf-forming graminoids, forbs matted, creeping, or in rosettes (Cole, Monz 2002 ) Moss Campion, Silene acaulis: Matted forb Alpine Avens, Geum rossii : Creeping forb

+ Importance of human disturbance on alpine plant communities Diversity primarily limited by temperature stress Disturbance and competition a secondary role. A predicted result of global warming is a shift in the equilibrium between stress, disturbance, and competition in alpine ecosystems (Kammer, Mohl 2002). Forget-me-nots

+ Question Is there a disturbance effect on the trailside communities of alpine vegetation on Arapaho Pass and Mount Yale? Does the effect differ among two different alpine sites (Arapaho Pass, Mount Yale) Arapaho Pass

+ Hypothesis Alternate Hypothesis There is a significant difference in communities near the trail and away from the trial. Predictions: Species richness reduced alongside trails. Study on trampling shows a reduction in species richness (Klug et al. 2002). More resistant plants where disturbance effect is lower. Null Hypothesis There is no difference in communities.

+ Site 1: Arapaho Pass Indian Peaks Wilderness Elevation: 3620m Community: Alpine Meadow 6 degrees slope 128 degrees SE Topography: Ridge exposed to high winds and weather

+ Site 2: Mount Yale Collegiate Peaks Wilderness (near Buena Vista) Elevation: 3810m Community: Alpine Meadow 24 degrees slope 260 degrees SW

+ Methods 50m transect along trail Daubenmire Plot pairs Trail, 3m Off Trail Measures Species Richness Average Height (cm) Use ANOVA to assess the difference in each site and for trail plots and off trail plots Number of resistant and non-resistant species Chi-Squared test Replication & Random sampling 5 plot pairs at Arapaho site 3 plot pairs at Mount Yale Limitations Time: small sample size Knowledge of plant species (mistakes)

+ Species Richnes Two factor ANOVA test not significant all p values >0.05 Disturbance: 0.87 Both (Disturbance X Site) : 0.44 Sites (Yale vs Arapaho): 1

+ Height of Vegetation Two-factor ANOVA Results: Disturbance: p=0.17 Both (disturbance X sites): p=0.06 Sites (Yale vs Arapaho): p= Heights were not significantly different on Trail and off Trail Significantly different between sites Arctic Sandwort

+ Resistance Chi-Squared Test p= 0.10 Not significantly different between sites More resistant species on Arapaho Pass More non-resistant species on Mount Yale

+ Discussion Strength of disturbance effect varies with different conditions and topography Mount Yale showed highest difference in average height and species richness Arapaho pass plants already adapted to harsher conditions Ridge exposed to high winds Mount Yale vegetation more protected Slope only facing one direction Plant mechanisms important on the effect of trampling (Cole, Monz 2002). Future Research # individuals Species Diversity: Shannon-Weiner Index Evenness (E) Total percent cover on the 50m transect Comparing the disturbance effect among many sites

+ References Cole, David and Christopher Monz Trampling Disturbance of High-Elevation Vegetation, Wind River Mountains, Wyoming, U.S.A. Journal of Arctic, Antarctic, and Alpine Research. 34(4): Kammer, Peter and Adrian Mohl Factors Controlling Species Richness in Alpine Plant Communities: An Assessment of the Importance of Stress and Disturbance. Journal of Arctic, Antarctic, and Alpine Research. 34(4): Klug, Brigitte, Gabriele Scharfetter-Lehrl and Ernst Scharfetter Effects of Trampling on Vegetation above the Timberline in the Eastern Alps, Austria. Journal of Arctic, Antarctic, and Alpine Research. 34(4): United States National Vegetation Classification

+ Apendix Species Identification Charts Frequency of Species Soil Samples

+ Species identification

+ Frequency of Species More dominant species in the trail plots Three species found in 5/5 trail plots Alpine Avens Geum rossii, Graminoid 1, Moss Campion Silene acaulis All are resistant plants

+ Soil Darker on Arapaho Pass Site differences Mount Yale SW facing, larger slope Arapaho Pass on an exposed ridge slightly SE facing