Browsing by Author "Welsh, Shawna"

The largest wetland drainage project in Michigan was initiated in 1912 near the town of Seney in the eastern Upper Peninsula. This project included the construction of a series of drainage ditches intended to prepare the land for agricultural use. The largest of these ditches was the 35 km-long Walsh Ditch. Much of the drained wetland affected by the Walsh Ditch is now managed by the U.S. Fish and Wildlife Service as part of Seney National Wildlife Refuge (Seney NWR). Starting in 2002, a series of earthen ditch plugs were installed along the length of the ditch found within Seney NWR (and adjacent to the Seney Wilderness Area) in an attempt to restore the hydrology and ecological integrity to the affected wetlands and streams. The plugs North of C-3 Pool were completed in 2002. The ditch plugs South of C-3 Pool were completed in 2005. This study explores the effect of the ditch plugs on the hydrology and vegetation structure in the adjacent landscape north of C-3 Pool at multiple scales. Plot level measurements of hydrology and vegetation, combined with an analysis of landcover change over the entire study area, indicate that some areas are converting from artificial upland communities created by wetland drainage to more natural wetland community types. Mortality of upland tree species and colonization by typical wetland species are good indications that these sites will continue to develop into wetland ecosystems over time. However, some areas have shown no response to the hydrologic restoration. This is expected, as areas of the landscape were upland (referred to as “pine islands” in the literature) before Walsh Ditch and should remain so as natural hydrology is restored to the area. Landcover change analysis showed a decrease in open water of 90.82 ha, a decrease of upland area of 67.88 ha and an increase in wetland area of 151.88 ha. The areas of change were concentrated around stream channels and in the area just east of Walsh Ditch. With time, it is possible that areas further removed from the ditch will show a shift towards more natural hydrology and vegetation composition, but for the areas furthest removed from the ditch this may require active management.