Longitudinal stream synoptic monitoring tracks chemicals along watershed continuums: a typology of trends.
Sujay S Kaushal, Carly M Maas, Paul M Mayer, Tammy A Newcomer-Johnson, Stanley B Grant, Megan A Rippy, Ruth R Shatkay, Jonathan Leathers, Arthur J Gold, Cassandra Smith, Evan C McMullen, Shahan Haq, Rose Smith, Shuiwang Duan, Joseph Malin, Alexis Yaculak, Jenna E Reimer, Katie Delaney Newcomb, Ashley Sides Raley, Daniel C Collison, Joseph G Galella, Melissa Grese, Gwendolyn Sivirichi, Thomas R Doody, Peter Vikesland, Shantanu V Bhide, Lauren Krauss, Madeline Daugherty, Christina Stavrou, MaKayla Etheredge, Jillian Ziegler, Andrew Kirschnick, William England, Kenneth T Belt
Author Information
Sujay S Kaushal: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Carly M Maas: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Paul M Mayer: United States Environmental Protection Agency, Office of Research and Development, Center for Public Health and Environmental Assessment, Pacific Ecological Systems Division, Corvallis, OR, United States.
Tammy A Newcomer-Johnson: United States Environmental Protection Agency, Center for Environmental Measurement and Modeling, Watershed and Ecosystem Characterization Division, Cincinnati, OH, United States.
Stanley B Grant: Occoquan Watershed Monitoring Laboratory, The Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Manassas, VA, United States.
Megan A Rippy: Occoquan Watershed Monitoring Laboratory, The Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Manassas, VA, United States.
Ruth R Shatkay: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Jonathan Leathers: University of Maryland, College Park, MD, United States.
Arthur J Gold: Department of Natural Resources Science, University of Rhode Island, Kingston, RI, United States.
Cassandra Smith: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Evan C McMullen: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Shahan Haq: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Rose Smith: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Shuiwang Duan: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Joseph Malin: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Alexis Yaculak: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Jenna E Reimer: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Katie Delaney Newcomb: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Ashley Sides Raley: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Daniel C Collison: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Joseph G Galella: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Melissa Grese: AKRF, Inc., Hanover, MD, United States.
Gwendolyn Sivirichi: AKRF, Inc., Hanover, MD, United States.
Thomas R Doody: Department of Geology, Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, United States.
Peter Vikesland: The Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, United States.
Shantanu V Bhide: Occoquan Watershed Monitoring Laboratory, The Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Manassas, VA, United States.
Lauren Krauss: Occoquan Watershed Monitoring Laboratory, The Charles E. Via, Jr. Department of Civil and Environmental Engineering, Virginia Tech, Manassas, VA, United States.
Madeline Daugherty: University of Maryland, College Park, MD, United States.
Christina Stavrou: University of Maryland, College Park, MD, United States.
MaKayla Etheredge: University of Maryland, College Park, MD, United States.
Jillian Ziegler: University of Maryland, College Park, MD, United States.
Andrew Kirschnick: University of Maryland, College Park, MD, United States.
William England: University of Maryland, College Park, MD, United States.
Kenneth T Belt: Department of Geography and Environmental Systems, University of Maryland Baltimore County, Baltimore, MD, United States.
There are challenges in monitoring and managing water quality due to spatial and temporal heterogeneity in contaminant sources, transport, and transformations. We demonstrate the importance of longitudinal stream synoptic (LSS) monitoring, which can track combinations of water quality parameters along flowpaths across space and time. Specifically, we analyze longitudinal patterns of chemical mixtures of carbon, nutrients, greenhouse gasses, salts, and metals concentrations along 10 flowpaths draining 1,765 km of the Chesapeake Bay region. These 10 longitudinal stream flowpaths are drained by watersheds experiencing either urban degradation, forest and wetland conservation, or stream and floodplain restoration. Along the 10 longitudinal stream flowpaths, we monitored over 300 total sampling sites along a combined stream length of 337 km. Synoptic monitoring along longitudinal flowpaths revealed: (1) increasing, decreasing, piecewise, or no trends and transitions in water quality with increasing distance downstream, which provide insights into water quality processes along flowpaths; (2) longitudinal trends and transitions in water quality along flowpaths can be quantified and compared using simple linear and non-linear statistical relationships with distance downstream and/or land use/land cover attributes, (3) attenuation and transformation of chemical cocktails along flowpaths depend on: spatial scales, pollution sources, and transitions in land use and management, hydrology, and restoration. We compared our LSS patterns with others from the global literature to synthesize a typology of longitudinal water quality trends and transitions in streams and rivers based on hydrological, biological, and geochemical processes. Applications of LSS monitoring along flowpaths from our results and the literature reveal: (1) if there are shifts in pollution sources, trends, and transitions along flowpaths, (2) which pollution sources can spread further downstream to sensitive receiving waters such as drinking water supplies and coastal zones, and (3) if transitions in land use, conservation, management, or restoration can attenuate downstream transport of pollution sources. Our typology of longitudinal water quality responses along flowpaths combines many observations across suites of chemicals that can follow predictable patterns based on watershed characteristics. Our typology of longitudinal water quality responses also provides a foundation for future studies, watershed assessments, evaluating watershed management and stream restoration, and comparing watershed responses to non-point and point pollution sources along streams and rivers. LSS monitoring, which integrates both spatial and temporal dimensions and considers multiple contaminants together (a chemical cocktail approach), can be a comprehensive strategy for tracking sources, fate, and transport of pollutants along stream flowpaths and making comparisons of water quality patterns across different watersheds and regions.
