Ecosystem functions of mid-lake stands of common reed in Lake Poygan, Wisconsin
Mid-lake stands of common reed grass (Phragmites australis) have persisted in the shallow Winnebago Pool Lakes of east-central Wisconsin for more than 65 years. Previous research documented that the stands are declining in area with losses up to 94%. Our goal was to characterize the ecological functions of these stands, in part to assess the implications of their loss. To do so, we studied the common reed stands of Lake Poygan during summer, 1999. Common reed stands stabilized the silty/sandy substrate. Wind velocity and wave action were reduced on the downwind sides, and fine, organic sediment accumulated leeward relative to summer prevailing winds. Water clarity was greater on the leeward side. Within stands, dissolved oxygen was less variable, and temperature tended to be cooler. The 18 species of associated aquatic plants covered three or more times the area in the leeward side than windward side. Twenty-nine species of fish were found using the perimeter of the common reed stands. We expect that stand loss will be accompanied by loss of associated wetland vegetation, and the unique combination of habitat attributes afforded by these stands. The current conditions leeward of the stands suggest that stand loss will have a broader spatial effect on ecological characteristics, including fish populations, and thus the implications may be lakewide.
Anthony O. Gabriel & Leo R. Bodensteiner (2011) Ecosystem functions of mid-lake stands of common reed in Lake Poygan, Wisconsin, Journal of Freshwater Ecology, 26:2, 217-229, DOI: 10.1080/02705060.2011.555202
Journal of Freshwater Ecology
© 2011 Taylor & Francis