Wednesday, August 6, 2008
Exhibit Hall CD, Midwest Airlines Center
Background/Question/Methods
Lichen communities are an important component of Antarctic terrestrial ecosystems. Lichens are the most species-rich plant functional group in terrestrial ecosystems of the maritime Antarctic. Faunal colonies (e.g. penguins) can negatively affect lichen communities through trampling and dunging, and are significant sources of nutrients that may influence lichen distributions. We sampled 7 terrestrial sites along the Antarctic Peninsula during a 10 day trip to Antarctica in December of 2007 as part of the NSF-funded International Polar Year Research and Educational Opportunities in Antarctica for Minorities (IPY-ROAM) program. This study contributed to a student/teacher group project that examined how nutrients from penguin colonies affected terrestrial ecosystem structure and function. This independent study project quantified lichen diversity and abundance at each of the sites visited. Due to time constraints at each site landing, a rapid line-point intercept sampling method along a 10-30 meter transect was implemented to obtain species richness and cover of lichens. Lichens were also sampled within two 3 meter belts along each transect in order to obtain a species area curve for each of the sites sampled. Transects were situated in locations subjectively gauged as representative vegetation cover at each landing. Snow cover and the proximity to penguin colonies were also important factors in determining transect locations. Penguin densities were calculated at each landing site through the use of photographs, and GPS locations for each transect were obtained using a Garmin GPS unit. Soil samples were taken along each transect and are currently being analyzed for their nitrogen and carbon content and isotopic signature.
Lichen communities are an important component of Antarctic terrestrial ecosystems. Lichens are the most species-rich plant functional group in terrestrial ecosystems of the maritime Antarctic. Faunal colonies (e.g. penguins) can negatively affect lichen communities through trampling and dunging, and are significant sources of nutrients that may influence lichen distributions. We sampled 7 terrestrial sites along the Antarctic Peninsula during a 10 day trip to Antarctica in December of 2007 as part of the NSF-funded International Polar Year Research and Educational Opportunities in Antarctica for Minorities (IPY-ROAM) program. This study contributed to a student/teacher group project that examined how nutrients from penguin colonies affected terrestrial ecosystem structure and function. This independent study project quantified lichen diversity and abundance at each of the sites visited. Due to time constraints at each site landing, a rapid line-point intercept sampling method along a 10-30 meter transect was implemented to obtain species richness and cover of lichens. Lichens were also sampled within two 3 meter belts along each transect in order to obtain a species area curve for each of the sites sampled. Transects were situated in locations subjectively gauged as representative vegetation cover at each landing. Snow cover and the proximity to penguin colonies were also important factors in determining transect locations. Penguin densities were calculated at each landing site through the use of photographs, and GPS locations for each transect were obtained using a Garmin GPS unit. Soil samples were taken along each transect and are currently being analyzed for their nitrogen and carbon content and isotopic signature.
Results/Conclusions
Preliminary data from the transects using the Shannon Index suggest lichen diversity was high at Barrientos Island and Peterman Island. In addition, data from soil samples analyzed for nitrogen and carbon indicate lichen species richness was significantly lower at sites with higher concentrations of nitrogen and carbon (p-value 0.05, p-value 0.03). A weak negative correlation between penguin proximity and lichen cover indicates that distance from faunal communities is not a determinant factor for lichen colonization (r2 = 0.1548, p-value > 0.05).
