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National Wetland Condition Assessment (NWCA) Soil and Water Stable Isotope Data

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These datasets provide raw stable isotope data collected as part of the National Wetland Condition Assessment (NWCA).  δ15N and δ13C measured from 10-cm Standard Depth Soil Cores are reported for 2011, 2016, 2021 NWCA and δ2H and δ18O from surface water chemistry samples are reported for 2021 NWCA.

Impact/Purpose

One-day field collection efforts, such as those used by the Environmental Protection Agency’s (U.S. EPA’s) National Wetland Condition Assessment (NWCA), provide limited information about important wetland functions, such as the processing and removal of nitrogen. To address this problem Amanda Nahlik, Catrina Nowakowski (ORISE), Renee Brooks, Jana Compton, Lisandra Trine, and Bill Rugh of EPA-ORD-PESD have collected, run, and QAed soil and water samples associated with the 2011, 2016, and 2021 NWCA surveys. This isotope data supports critical research to understand nitrogen processing and denitrification in wetlands on a national scale.

Citation

Nahlik, A., Catrina Nowakowski, R. Brooks, J. Compton, L. Trine, AND W. Rugh. National Wetland Condition Assessment (NWCA) Soil and Water Stable Isotope Data. U.S. Environmental Protection Agency, Washington, DC, 2025. [DOI: 10.23719/1532409]

Download(s)

DOI: National Wetland Condition Assessment (NWCA) Soil and Water Stable Isotope Data
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Last updated on July 18, 2025
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