RESPONSE OF SAGO PONDWEED TO WATER LEVEL FLUCTUATIONS

Yao Yin1,2, Heidi A. Langrehr3, and Sara J. Lubinski2
1The University of Tennessee, Knoxville, TN 37916,  2U.S. Geological Survey
Biological Resource Division, Environmental Management Technical Center,
Onalaska, WI 54650;  2Wisconsin Department of Natural Resources, Long Term
Resources Monitoring Program Field Station, Onalaska, WI 54650.

Sago pondweed (Potamogeton pectinatus L.) produces fruit and tubers for
wildlife food and provides good fish habitat.  We wish to reveal patterns in
which the population of  sago pondweed responds to water level fluctuations in
Pool 8 of the Upper Mississippi River.  We analyzed the vegetation data
collected seasonally from 1992 to 1997 by the Long Term Resource Monitoring
Program, and the daily surface water level data of the Mississippi River collected
by the U.S. Army Corps of Engineers.  The occurrence of sago pondweed was
the dependent variable, and water depth and the number of growing days were
the independent variables of our regression models.  Several models fit one or
two years' field data, which indicates water level fluctuation is a principal factor. 
However, no single model fits every year's field data, which indicates additional
environmental factors have to be added into the models.

Keywords: sago pondweed, Mississippi River, Potamogeton pectinatus, water
level fluctuation, submersed plant


Contact: Yao Yin, 575 Lester Avenue, Onalaska, WI 54650. Telephone 608-783-7550, FAX 608-783-8058, email yao_yin@usgs.gov

Presentation preference: poster, not willing to convert to platform

The paper is not authored by a student