Contrast and comparison of aerial algal communities from two distinct regions in the U.S.A., the Great Smoky Mountains National Park (TN) and the Lake Superior region.

Abstract

The Great Smoky Mountains National Park (GSMNP) and the land surrounding Lake Superior (LSR) are rich in aerial habitats and support diverse aerial algal communities. Currently, the ecology of aerial algal communities is not well understood. Furthermore, no research has been published directly comparing aerial algal floras between geographic regions. We analyzed the ecology of the aerial habitats within each region and compared the overall algal flora between these two regions. Physical and chemical factors, including aspect, moisture levels, light levels, and pH were measured at each sampling location. Communities from both regions were dominated by cyanobacteria with average relative abundances >50% in both the GSMNP and LSR. The aerial algal flora of the GSMNP as a whole was not distinct from that of the LSR. Taxa unique to each region were found to be present in low abundances, while many taxa present in higher abundance were found in both the LSR and GSMNP communities. Non-metric multidimensional scaling ordination of the community data from both regions identified two distinct communities within the GSMNP. Moisture availability within sites contributed to this separation with higher mean relative of abundances of cyanobacteria in the drier habitats and higher mean relative abundances of chlorophytes and diatoms in the wetter habitats.