Diana Oviedo Vargas, Ph.D.

https://stroudcenter.org/wp-content/uploads/Diana-Oviedo-Vargas-1.jpg 800 800 Stroud Water Research Center Stroud Water Research Center https://stroudcenter.org/wp-content/uploads/Diana-Oviedo-Vargas-1.jpg July 21, 2017 December 1, 2025

Associate Research Scientist, Principal Investigator

Watershed Biogeochemistry Group

Contact

doviedo@stroudcenter.org
tel. 610-268-2153, ext. 1263
970 Spencer Road, Avondale, PA 19311

https://orcid.org/0000-0001-9333-0962

Google Scholar | Download CV

Interests and Expertise

Diana Oviedo Vargas’s research seeks to improve understanding of the elemental cycles in streams, rivers, and estuaries, and how they are linked to each other, the water cycle, and the terrestrial ecosystem at surface and subsurface levels.

Some of her current research interests include the nitrogen and phosphorus transport and transformation in fluvial systems and how human activities such as agriculture and urbanization can affect these processes; the quantification and characterization of the multiple carbon pools and fluxes in aquatic ecosystems and their role in global climate change; and the effects of emerging contaminants, like PFAS and pesticide residues, on the health of streams and rivers.

Oviedo Vargas’s expertise includes aquatic ecosystems in temperate and tropical zones, spanning the full river continuum — from headwaters to large rivers to estuaries and the coastal ocean.

Education

Ph.D., environmental sciences, Indiana University, Bloomington, Indiana.
M.S., environmental sciences, Indiana University, Bloomington, Indiana.
B.S., chemistry, University of Costa Rica, San José, Costa Rica.

Professional Experience

Associate research scientist, Stroud Water Research Center, 2025–present.
Assistant research scientist, Stroud Water Research Center, 2017–2025.
Postdoctoral research associate, Department of Marine Earth and Atmospheric Sciences, North Carolina State University, Raleigh, North Carolina, 2013–2017.
Associate instructor, School of Public and Environmental Affairs, Indiana University, Bloomington, Indiana, 2011–2013.
Teaching assistant, Analytical and organic chemistry laboratories, University of Costa Rica, San José, Costa Rica, 2004–2007.
Research assistant, Natural Products Research Center, University of Costa Rica, San José, Costa Rica, 2004–2007.

Publications

Hydroclimate and landscape diversity drive highly variable greenhouse gas emissions from tropical and subtropical inland waters

Duvert, C., Borges, A.V., Calamita, E., et al. 2025. Nature Water 3: 1303–1317.

Reduction in nitrification during the early transition from conventional to organic farming practices

Price, J.R., D. Oviedo-Vargas, M. Peipoch, M.D. Daniels, and J. Kan. 2025. Ecosphere 16(8): e70375.

High fecal indicator bacteria in temperate headwater streams at baseflow: implications for management and public health

D.T. Myers, L. Zgleszewski, R. Bier, J.R. Price, S. Morgan, J.K. Jackson, D. Oviedo-Vargas, M. Daniels, D.B. Arscott, J. Kan. 2025. Water Research X 29: 100347.

Quantification of PFAS in soils treated with biosolids in ten northeastern US farms

Oviedo-Vargas, D., J. Anton, S. Coleman-Kammula, and X. Qin. 2025. Nature Scientific Reports 15: Article 5582.

Seasonal variation in land cover estimates reveals sensitivities and opportunities for environmental models

Myers, D.T., D. Jones, D. Oviedo-Vargas, J.P. Schmit, D.L. Ficklin, and X. Zhang. 2024. Hydrology and Earth System Sciences 28(23): 5295–5310.

See publications by all Stroud Center authors

Scientists Oviedo and Dow Make Waves in Freshwater Science

We congratulate Diana Oviedo Vargas, Ph.D., and Charles Dow, Ph.D., on recent achievements highlighting their commitment to advancing freshwater science.

These Contaminants Are Reaching Our Surface Water

“Forever chemicals” in sewage sludge are reaching waterways, Stroud Center finds and New York Times reports.

Silk Grass Farms is a Force for Good

To understand the state of its water resources and how to protect them, Silk Grass Farms asked the Stroud Center to provide expert guidance.

The Economic Case for Watershed Restoration

Restoration can fuel economic growth, cut costs, create jobs, and provide opportunities for businesses, all while supporting freshwater ecosystems.

Study Points to Farmland as Possible Source of PFAS in Fish

The Stroud Center and the Center for PFAS Solutions have been studying how much biosolids are contaminating farmland and adjacent waters since 2021.

Study: Community Science Can Aid Water Resource Monitoring

After examining water quality data from community scientists, researchers say it has value, but volunteers need support.