Twin Cities WRS Seminar
Prairie Pothole Wetlands: How Restoration Strategies Influence Ecosystem Structure and Function in an Agricultural Landscape
Wetland restoration is a priority in the Prairie Pothole Region of USA and Canada where historically most wetlands were drained for agriculture. Wetland restorations often include sediment excavation to remove accumulated sediment, thus increasing water storage and
exposing seed banks. We examined whether sediment excavation during restoration reduces soil and surface water nutrient content with analyses of 55 restored agricultural wetlands across west-central Minnesota. Excavation reduced soil and surface water nutrient availability. Nitrate concentrations were consistently very low throughout the growing season and did not differ between treatments, suggesting that excavation does not influence the high capacity of restored wetlands to remove or assimilate inorganic nitrogen. Our results suggest that, while more costly, sediment excavation improves wetland restoration outcomes for water quality.