PARENT SESSION
Poster Session # 17: Aquatic Systems.

Thursday, August 7 Presentation from 5:00 PM to 6:30 PM. SITCC Exhibit Hall B.

Effects of herbivory, sediment disturbance, and hydrology on plant recruitment in a Lake Erie coastal wetland.

Bowers, Richard^*,1, Barry, Matthew², de Szalay, Ferenc³, ¹ Edwards-Pitman Environmental, Inc., Smyrna, Georgia² Arizona State University, Tempe, Arizona³ Kent State University, Kent, Ohio

ABSTRACT- In 2000, we examined plant recruitment on exposed mudflats in a Lake Erie coastal marsh during two years of below average water levels. Mudflat vegetation was sampled in shallow, medium and deep water transects and compared to germinable seeds found in sediments from 0-15 cm below the surface. Using 1m² quadrats, we examined the effects of sediment disturbance and herbivory on plant recruitment in 2000. Vegetation was then sampled in 2001 to assess how well the disturbance/herbivory experiment predicted plant communities that became established on the mudflats. Eighteen species were found on mudflats and 19 species were reared from the seedbanks in 2000. The shallow transect had the highest number of plants, but the deep transects had the highest seed abundance and richnesss. Herbivory decreased both plant cover and richness, and sediment disturbance decreased taxa richness; however responses varied among taxa. Our results indicate that abundant seedbanks exist in this wetland, but plant recruitment will be restricted to shallow areas due to turbidity. Communities in 2001 were more diverse (40 species) than predicted from vegetation in 2000. This was probably because propagules were introduced from nearby habitats. Communities in 2001 were most similar to ungrazed and undisturbed quadrats in 2000.

Key words: Lake Erie, Plant Recruitment, Coastal Wetlands