Abstract Detail

Bryological and Lichenological Section/ABLS

Scharnagl, Klara [1], Ebert-May, Diane [2].

Forty years later: changes in lichen communities on alpine tundra at Niwot Ridge, Colorado.

Alpine tundra contains unique ecosystems that form island communities at the tops of mountains. With increasing impacts of global climate change, major shifts are predicted in alpine tundra communities, including encroachment of the treeline, increase in shrub cover, potential community homogenization and species loss. The resilience of alpine tundra ecosystems remains under investigation. Research in other ecosystems indicates that cryptogams such as lichens and mosses react differently to microclimatic changes than herbaceous and woody plants do. Some montane plants have been able to cope with the effects of global climate change by moving upslope, or into newly available temperature niches. Given the generally slow growth of lichens [mere millimeters or centimeters per year], it is difficult to predict how lichen communities will be affected by global climate change, and whether they will be able to move into more suitable microclimates. Here we present results from a re-survey of the lichens in thirty long-term research plots on the Niwot Ridge Long-term Ecological Research (LTER) site. In 1971, thirty permanent 1x10m plots that represent the range of vegetation and microclimate in the Saddle portion of Niwot Ridge were surveyed for lichen cover. Microsite temperature and snow accumulation influence the vegetation structure in the Saddle, resulting in discernible fellfield, dry meadow, moist shrub, shrub tundra, moist meadow, snowbed and wet meadow. In 2014, the thirty plots on Niwot Ridge were visited and re-surveyed for lichen cover and species richness. Each 1x1m quad was visually surveyed for lichen species presence and percent cover. Notes were made if new species, that is, species not recorded in the original survey, were present. Total vegetation cover, light availability and surface temperature were also recorded. Overall, there were more gains than losses of lichen species across plant communities with the exception of cyanolichens, which often decreased or disappeared from the plots. Alpine lichen communities, though slow-growing, are not static, and could serve as important indicators of ecosystem sensitivity to edaphic, atmospheric, and microclimatic change. There are very few long-term field studies of lichens. Our study represents the first time interval of ongoing monitoring of lichen communities on Niwot Ridge.

1 - Michigan State University, Plant Biology, 612 Wilson Rd, East Lansing, MI, 48824, USA
2 - Michigan State University, Plant Biology, 612 Wilson Rd, East Lansing, MI, 48824, United States

Keywords:
lichen
long-term
Community ecology
global change
alpine tundra.

Presentation Type: Oral Paper:Papers for Sections
Session: 38
Location: Salon 8/The Shaw Conference Centre
Date: Tuesday, July 28th, 2015
Time: 9:30 AM
Number: 38005
Abstract ID:372
Candidate for Awards:A. J. Sharp Award