Wetland Vegetation Development

Lee Luckeydoo, a doctoral student in Environmental Science at The Ohio State University, monitors vegetation community development at the WRSIS wetlands. Quadrats are placed in each zone of the wetland: open water, average water line, and shore. Within these quadrats, species and their abundance are recorded throughout the growing season. The WRSIS wetlands are being allowed to revegetate passively, with the only area planted being the buffer area, above the wetland, for erosion control. This revegetation options relies on the seed bank present on site, and the delivery of seeds from other sources by wind, wildlife or other vectors.

Passive revegetation should encourage the establishment of species adapted to local conditions which can also tolerate the conditions created by using agricultural drainage as a water source. During 1998 species richness, or total number of species, was 51 at the Defiance location, 44 at the Van Wert location, and 32 at the Fulton location. Less than half of the total number of species on each site were considered to be wetland species by the National List of Species that occur in wetlands of Ohio. Time and appropriate conditions for delivered seeds will play a large role in the successful establishment of vegetation on these sites. Diversity of vegetation over time will be evaluated with Simpson's and Shannon-Wiener diversity indices. In addition to surveys of extant vegetation, seed banks are being evaluated on these sites. In 1998, a seed bank study was conducted on the Defiance site soils and found seven additional wetland species in the seed bank. The basin of the wetland was modified in early 1999 to create more mudflat conditions to encourage the growth and establishment of these new species and the spread of established species. Future and ongoing plans for the WRSIS wetlands include: (1) estimation of algal and vascular vegetation biomass, (2) studies on seed and propagule delivery to the WRSIS sites, (3) comparison with reference wetlands, and (4) continued vegetation surveys.Lee holding a quadrat measuring device. Vegetative surveys were conducted in 1 m by 1 m quadrats. Picture taken at the Defiance County (DARA) WRSIS site.

Seed bank study using germination method. Tub in the foreground is the flooded treatment. Tub in the background is the mudflat treatment. Seedlings are grown from soil taken from three zones in the wetland - open water, waterline, and shore. Purpose is to estimate viable seeds in seedbank under simulated conditions. Study started in 1998 and continues in 1999.

Photo of vegetation established at the Van Wert County WRSIS site, 1999. Sedges, bulrushes and cattails growing in sedimentation zone encourage microbial reactions such as denitrification.