Northern Prairie Wildlife Research Center
North Dakota State University, Department of Soil Science, Webster Hall, P.O. Box 5638, Fargo, ND 58105
Concern over damage to wetlands caused by cultural practices has prompted federal efforts (EMAP-Wetlands) to develop methods that can be used to monitor the ecological "health" of wetlands. Proceeding into a two-year pilot study with the understanding that soils are potent indicators of long-term environmental conditions, we are testing field and laboratory methods that can be used to measure potential wetland degrading processes including sedimentation, salinization, and nutrient loading. In 1992, we sampled a total of 40 wetlands in three different regional strata. These regional strata, were defined by each region's wetland density and health defined by land use; wetlands surrounded by grassland were considered to have higher health than wetlands surrounded by cropped land. We have compiled first-year field data on soil morphology, basin morphology, and in situ salinity. Soil samples were analyzed in the laboratory for nitrate, phosphorus, and organic matter content, pH, and electrical conductivity. Preliminary results show significantly higher levels of nitrate and phosphorus in wetlands surrounded by cropped lands compared to wetlands surrounded by grasslands. We did not see significantly different levels of organic matter, soluble salts, or pH in wetlands surrounded by cropped land versus grassland.