Functional Role Of Fringing Floodplain Wetlands On Streams In South-Central Michigan.
College of Liberal Arts and Sciences
Organic matter (OM) dynamics in streams fluctuate predictably with flow regime higher flows yield increased OM export. We studied the role of fringing wetlands on OM dynamics under two discharge regimes in three river systems. Fringing wetlands common in this region are characterized by wetland plants, saturated soils, and are bisected by a persistent river channel. At all sites, increased discharge elevated TOM concentration at upstream control and wetland sites (60-70% increase; range 4.4 18.0 g/m3). Nutrient limitation (ambient concentrations and nutrient diffusers) indicated that nitrogen dynamics in wetlands shifted from storage to export at low vs. high flows, respectively. Fringing wetlands tended to act as net OM producers (exporters) no matter discharge regime, although one stream, Augusta Creek, was storing OM during base flow. Results in part contradict the role of wetlands as sites of OM retention, but this functional role reversal is not surprising given the close proximity of the fringing wetlands to their respective streams. Furthermore, results imply that fringing wetlands play an important role supporting detrital food webs.
JASM - Joint Annual Conference
Snyder, Eric B. and Overweg, Melissa L., "Functional Role Of Fringing Floodplain Wetlands On Streams In South-Central Michigan." (2014). Faculty Scholarly Dissemination Grants. 749.