HR: 09:30h
AN: NB21E-05    [Abstracts]
TI: Factors Affecting the Distribution of Wild Rice (Zizania palustris) and the Surrounding Macrophyte Community.
AU: * Pillsbury, R W
EM: pillsbur@uwosh.edu
AF: University of Wisconsin, Oshkosh, 800 Algoma Blvd., Oshkosh, WI 54901 United States
AU: McGuire, M
EM: mcguire@powerweb.net
AF: University of Wisconsin, Oshkosh, 800 Algoma Blvd., Oshkosh, WI 54901 United States
AB: A recent decline in wild rice wetlands is cause for concern due to its importance as a food source, refuge for wildlife, and cultural significance. Sixty wetlands in Wisconsin and Minnesota (USA) were sampled, with approximately equal numbers displaying dense, moderate and sparse wild rice production. Chemical, physical, and watershed parameters were measured as well as macrophyte densities. Data were analyzed using multivariate statistics (CCA). Moderate levels of phosphorus appear beneficial to the overall success of wild rice, while free-floating macrophytes show an overwhelming positive response to higher levels of P. The distribution of macrophytes bordering wild rice beds is correlated to pH,with Potamogeton robbinsii and filamentous green algae responding most strongly to its increase. Healthy stands of wild rice exhibit a narrow circum-neutral range of pH (6.1-8.0)which is significantly different from the greater range exhibited by sparse wild rice wetlands (6.5-8.5). This pattern was paralleled when considering depth which suggests that deeper wetlands may be more susceptible to wild rice loss. Management of existing wild rice wetlands should focus monitoring on pH, depth, phosphorus concentrations and shore development. We are currently using this data base to locate the best reintroduction sites for wild rice.
DE: 1890 Wetlands
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly