ABSTRACT
Wetlands are complex ecosystems that are dependent on hydrologic processes and affected by water chemistry. The Fish Lake Environmental Education Center near Lapeer, MI, is glacially influenced and contains a large bog and multiple kettles that contain ephemeral wetlands in the spring. Previous studies indicated that groundwater flow direction at the southern end of the site is towards Fish Lake, but the extent to which groundwater and surface water are interacting with the wetlands north of the lake is unclear. The goal of this project was to understand the relative contributions of precipitation and groundwater in the bog and kettle wetlands north of Fish Lake. Groundwater and surface water samples were collected monthly in the fall and winter and biweekly in the spring and summer between May 2022 and September 2023. Values of pH, electrical conductivity, water levels, nitrate, nitrite, phosphorus, and iron were analyzed and used to determine water source. Sites with low pH and low electrical conductivity were determined to be precipitation influenced. Conceptual site models based on project data suggest that the wetlands to the north are more precipitation sourced and become more heavily groundwater influenced to the south towards the lake. Glaciated regions of the Upper Midwest with similar topography can apply these methods to determine relative sources of water in different wetlands.
