PARENT SESSION
Wednesday, August 9, 5:00-6:30 pm
Poster Session 19 - Wetland, riparian, and coastal ecology
Exhibit Hall, Ballroom Level, Cook Convention Center
Shade responses of sedges from a light gradient in constructed wetlands.
Carroll, Laura1, Deskins, William1, Robison, Laura 1, Gleeson, Scott1, 1 University of Kentucky, Lexington, KY
ABSTRACT- Gradient analysis of naturally colonized plant species distributions in a set of constructed vernal wetlands suggested control by ambient light levels (caused by variation in surrounding vegetation). To test this we grew four species of sedge (Carex bebbii, C. vulpinoidea, C. hirsutella, and C. crinita) from these communities that had their peak abundances at different points along this presumptive light gradient. The species were grown in a greenhouse under four levels of shade (0, 25, 50, and 92% shade), and also with and without competition (from a single sedge species). While all species grew best in high light and without competition, the species that grew best in low light were those from the shadier habitats. This, and related photosynthetic performance, were consistent with variation in shade tolerance as one possible mechanism controlling sedge distributions in these wetlands.
Key words: wetland, sedge, species distributions