Concurrent Session: Wetland science potpourri
11:00 AM - 12:00 PM Thu
Co-author: Alan Herlihy, Oregon State University
Title: Visualizing wetland water: Watershed and buffer conditions organize cross-USA wetland water quality
Abstract: The effects of watershed and riparian anthropogenic activities on lake and stream water quality are well established, but they have been much less studied in wetlands. Here we use data from the 2016 National Wetland Condition Assessment, collected via a U.S. EPA partnership with states and tribes, to characterize wetland water quality in relation to adjacent and watershed-scale anthropogenic impacts. The dataset has measures of pH, dissolved organic carbon (DOC), nutrients, salinity, turbidity, and algal chlorophyll for 525 inland wetlands across the continent, including 23 in Wisconsin, 31 in Minnesota, and 10 in Michigan. Wetland-adjacent pressure scores are synthesized from field checklist items (e.g., livestock, vehicle ruts, dredge/fill) and watershed pressure scores are equated to percent agriculture and urban landcover. Only 18% of sampled wetlands had no anthropogenic pressure, but pressure levels were uncorrelated across scales and varied considerably across biogeographic regions and hydrogeomorphic types. Watershed-scale pressure was the best predictor of increased nutrients, while adjacent-scale pressure best-predicted changes to DOC. pH, and salinity. Water quality responded to landscape pressures even in wetland types lacking inflows (e.g., flats, closed depressions) which suggests that wetlands are generally connected to rather than isolated from the surrounding upland. Water quality in WI/MN/MI wetlands generally followed cross-USA patterns, but boggy sites were more common and low-nutrient sites were rare. Our presentation will illustrate these patterns for relevant combinations of wetland types and settings, including for upper midwest wetlands of particular interest to this conference.
Bio: Anett Trebitz, PhD, is a research ecologist with the U.S. EPA at the Duluth, Minnesota lab. In addition to her work on wetlands, she is involved with Great Lakes water quality monitoring and with invasive species early detection research.