Kirill Langer Vegetation Ecology Summer Semester July 2013 University of Colorado Mountain Research Station Plant Species Diversity in the Subalpine Elk Meadow

Introduction - North facing slopes are wetter on average than south facing ones, due to less snow accumulation (Hinckley et. al 2012) -Larger and longer exposure to sun on angled ground versus flat ground because of the larger surface area (Bennie et. al 2006) -The Elk Meadow is in the subalpine -Plant distributions -Does topography and aspect determine these distributions?

Introduction -Assess diversity of plant species in the Elk Meadow at the MRS -The Elk Meadow has an East, Flat, and South part -Its elevation is 10,000 feet Question: How does aspect and angle of slope impact plant diversity at South facing, East facing, and Flat areas at the subalpine Elk Meadow? The Elk Meadow (Google Maps 2013)

Introduction Hypothesis: The East and South facing slopes will have a larger species diversity than the flat area – I hypothesized that slope increases plant diversity

Methods East facing, South facing, and Flat areas at the Elk Meadow in the subalpine Six 20 X 50 cm Daubenmire plots per area Number of individuals of each species My data does not accurately represent the entire subalpine zone on the Coloradan front range, because of pseudo replication – However it is an accurate profile of the meadow

Methods I used the Jaccard’s Index to quantify the similarities in species diversity between the areas I looked at the species diversity differences between sites with a ANOVA and t-tests

Results 18 Species in total

Results The two species most representative of the three areas were Yarrow (Achillea millefolium) and Sedge (Carex Parryi) Each were present at nearly every site ANOVA Two Factor with Replication P-values: Topography: 0.95 Plant Spp: 0.37 Interaction: 0.62

Results The total species counts between the areas were similar Median: 5 Mode: 5 Mean: 4.94

Results Single Factor ANOVA P-value: 0.09 Individual t-tests showed no significant differences

Results Jaccard’s Index: East Flat South 50% 29.4%40% Similarity

Discussion Jaccard’s index found that sloped sites are not more similar to each other in species richness than to the flat site The ANOVA and t-tests showed that none of the areas species compositions were significantly different - This indicates angle of slope and aspect do not significantly affect species diversity This study is inconclusive, but future studies of aspects influence on diversity should aim for areas with larger slopes If I were to do this again, I would sample more areas, at multiple sites

Conclusions The subalpine Elk Meadow is dominated by Yarrow and Sedge Aspect and slope angle do not significantly affect plant diversity at the Elk Meadow My advice for vegetation diversity researchers interested in similar questions

Questions Do you have any thoughts or questions about my project?

References 1. Bennie, J. Hill, M. Baxter, R. Huntley, B. Influence of slope and aspect on long-term vegetation change in British chalk grasslands. Journal of Ecology 94 (2): 355– Hinckley, E.-L. S., Ebel, B. A., Barnes, R. T., Anderson, R. S., Williams, M. W., and Anderson, S. P.: Aspect control of water movement on hillslopes near the rain-snow transition of the Colorado Front Range, US, Hydrol. Process. in review, Mueller-Dombois, D. Ellenberg, H. Aims and Methods of Vegetation Ecology. The Blackburn Press. Caldwell, New Jersey US