TY - JOUR
T1 - Variation in surface and subsurface nitrogen cycling in headwater floodplain wetlands due to soil type and wetland condition
AU - Moon, Jessica B.
AU - Wardrop, Denice H.
AU - Fennessy, M. Siobhan
AU - Ingram, Hannah M.
AU - Britson, Aliana
AU - Okoro, Melanie Harrison
N1 - Funding Information:
This work was supported by the United States Environmental Protection Agency STAR Cooperative Agreement (Grant No. R-834262-01). We thank Nicole Kircher, Sabrina Arora, and Zachary Morrow from Kenyon College, and Kyle Martin, Marla Korpar, Rebecca Baker, and Brett Dietz from Penn State University for field and laboratory assistance. We are also grateful to Peter Groffman at the Cary Institute of Ecosystem Studies for allowing us to run SF samples in his laboratory; Erica Smithwick at Penn State University for the use of the Lachat Flow Injection Analysis System to run nitrate and ammonium samples; and Amanda Nahlik at the United States Environmental Protection Agency for running soil elemental analyses. We thank Karol Confer at the Penn State Water Quality lab for assistance and training of water chemistry instrumentation and Gregory Noe at the United States Geological Survey for addressing questions related to the mineralization core methodology. Finally, we thank Robert Brooks at Penn State University, and two anonymous reviewers for their suggestions on how to improve this manuscript. 6
Funding Information:
This work was supported by the United States Environmental Protection Agency STAR Cooperative Agreement (Grant No. R-834262-01). We thank Nicole Kircher, Sabrina Arora, and Zachary Morrow from Kenyon College, and Kyle Martin, Marla Korpar, Rebecca Baker, and Brett Dietz from Penn State University for field and laboratory assistance. We are also grateful to Peter Groffman at the Cary Institute of Ecosystem Studies for allowing us to run SF6 samples in his laboratory; Erica Smithwick at Penn State University for the use of the Lachat Flow Injection Analysis System to run nitrate and ammonium samples; and Amanda Nahlik at the United States Environmental Protection Agency for running soil elemental analyses. We thank Karol Confer at the Penn State Water Quality lab for assistance and training of water chemistry instrumentation and Gregory Noe at the United States Geological Survey for addressing questions related to the mineralization core methodology. Finally, we thank Robert Brooks at Penn State University, and two anonymous reviewers for their suggestions on how to improve this manuscript.
Publisher Copyright:
© 2020, Springer Nature B.V.
PY - 2020/10/1
Y1 - 2020/10/1
N2 - Headwater wetlands intercept, store, and transform nitrogen inputs from the landscape. However, uncertainties in rate estimates for processes such as denitrification in surface and subsurface soils hinder our ability to quantitatively predict the downstream water quality benefits of these headwater systems. We measured nitrogen pools and fluxes from surface (0 to 10 cm) and subsurface soils (~ 50 cm) of six headwater wetlands of low and high ecological condition (based on anthropogenic stressors) across three hydric soil types (Atkins, Holly, Udifluvent-Dystrochrept Complex). We quantified net nitrification (− 0.027 to 0.113 mg N kg soil−1 day−1), net ammonification (− 0.159 to 1.683 mg N kg soil−1 day−1), and potential denitrification rates (0.12 to 17.05 mg N kg soil−1 day−1) in surface soils during the fall. We also quantified potential denitrification rates in subsurface soils at 4 of the 6 sites in fall and spring (0.005 to 0.177 mg N kg soil−1 day1). Potential denitrification rates in surface soils varied with soil type, and rates were positively correlated with ground cover and the percentage of time the water level was between 0 and 10 cm below the surface. Potential denitrification rates of subsurface soil did not vary between condition groups or seasons; however, nitrous oxide yield was higher in the spring compared to the fall. At the plot scale, potential denitrification rates in surface soils were correlated with ammonification rates, and rates in subsurface soils were correlated with conductivity and ammonium levels. This work demonstrates the variability in surface and subsurface soil nitrogen cycling and highlights the need to investigate nutrient dynamics at multiple soil depths to accurately quantify the role of headwater wetlands in nitrogen removal at regional scales where soil properties are highly variable.
AB - Headwater wetlands intercept, store, and transform nitrogen inputs from the landscape. However, uncertainties in rate estimates for processes such as denitrification in surface and subsurface soils hinder our ability to quantitatively predict the downstream water quality benefits of these headwater systems. We measured nitrogen pools and fluxes from surface (0 to 10 cm) and subsurface soils (~ 50 cm) of six headwater wetlands of low and high ecological condition (based on anthropogenic stressors) across three hydric soil types (Atkins, Holly, Udifluvent-Dystrochrept Complex). We quantified net nitrification (− 0.027 to 0.113 mg N kg soil−1 day−1), net ammonification (− 0.159 to 1.683 mg N kg soil−1 day−1), and potential denitrification rates (0.12 to 17.05 mg N kg soil−1 day−1) in surface soils during the fall. We also quantified potential denitrification rates in subsurface soils at 4 of the 6 sites in fall and spring (0.005 to 0.177 mg N kg soil−1 day1). Potential denitrification rates in surface soils varied with soil type, and rates were positively correlated with ground cover and the percentage of time the water level was between 0 and 10 cm below the surface. Potential denitrification rates of subsurface soil did not vary between condition groups or seasons; however, nitrous oxide yield was higher in the spring compared to the fall. At the plot scale, potential denitrification rates in surface soils were correlated with ammonification rates, and rates in subsurface soils were correlated with conductivity and ammonium levels. This work demonstrates the variability in surface and subsurface soil nitrogen cycling and highlights the need to investigate nutrient dynamics at multiple soil depths to accurately quantify the role of headwater wetlands in nitrogen removal at regional scales where soil properties are highly variable.
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U2 - 10.1007/s11273-020-09741-0
DO - 10.1007/s11273-020-09741-0
M3 - Article
AN - SCOPUS:85090309665
SN - 0923-4861
VL - 28
SP - 727
EP - 751
JO - Wetlands Ecology and Management
JF - Wetlands Ecology and Management
IS - 5
ER -