Ion Clusters Reveal the Sources, Impacts, and Drivers of Freshwater Salinization
Population growth, land use change, climate change, and natural resource extraction are driving the salinization of freshwater resources worldwide. Reversing these trends will require data-centric approaches that identify salt sources, environmental drivers, and ecosystem responses. In this study, we applied principal component analysis and hierarchical clustering to identify ion covariance patterns, or "ion clusters," in Broad Run, an urban stream in the Mid-Atlantic United States. These clusters correspond to distinct hydrologic regimes and reveal specific salinization risks: (1) phosphorus pollution mobilized during summer storms (Cluster 1); (2) elevated concentrations of sulfate and bicarbonate during baseflow (Cluster 2), likely reflecting groundwater discharge; and (3) elevated specific conductance and sodium, chloride, and potassium ion concentrations during snowmelt and rain-on-snow events (Cluster 3), driven by deicer and anti-icer wash-off. These ion fingerprints offer a transferable framework for diagnosing salt sources, assessing ecological risk, and identifying management targets. Our findings underscore the need for next-generation stormwater infrastructure and smart growth policies to protect aquatic life in rapidly urbanizing watersheds.
Authors
- Ahmed Monofy (ORCID: https://orcid.org/0000-0001-9641-327X)
- Admin Husic (ORCID: https://orcid.org/0000-0002-4225-2252)
- Christina C. Davis (ORCID: https://orcid.org/0000-0002-9724-9587)
- Diver E. Marín
- Shantanu V. Bhide (ORCID: https://orcid.org/0000-0002-5248-0646)
- Bradley W. Schmitz
- Sydney Shelton (ORCID: https://orcid.org/0000-0002-1246-7412)
- Robert N. Brent (ORCID: https://orcid.org/0000-0003-3944-5421)
- Harold Post
- Shalini Misra (ORCID: https://orcid.org/0000-0002-9231-5995)
- Megan A. Rippy (ORCID: https://orcid.org/0000-0002-0575-8342)
- Stanley B. Grant (ORCID: https://orcid.org/0000-0001-6221-7211)
- Peter J. Vikesland (ORCID: https://orcid.org/0000-0003-2654-5132)
- Sujay S. Kaushal (ORCID: https://orcid.org/0000-0003-0834-9189)
- Erin R. Hotchkiss (ORCID: https://orcid.org/0000-0001-6132-9107)
- J. D. Gomez‐Velez (ORCID: https://orcid.org/0000-0001-8045-5926)
- Shannon Curtis
- Dongmei Alvi
Institutions
- James Madison University (US)
- Oak Ridge National Laboratory (US)
- Inova Loudoun Hospital (US)
- Watershed (GB)
- Earth System Science Interdisciplinary Center (US)
- Public Works (GB)
- Fairfax County Public Schools (US)
- ADS Environmental Services (Malaysia)
- University of Maryland, College Park (US)
- Virginia Tech (US)
- ENVIRON (United States) (US)
Publication Details
- Journal
- Environmental Science & Technology
- Published
- 2025-06-16
- DOI
- https://doi.org/10.1021/acs.est.5c04512
- Citations
- 3
- Primary Topic
- Smart Materials for Construction
- Type
- article
- Field-Weighted Citation Impact
- 1.51
Funders
- National Science Foundation
- Oak Ridge National Laboratory