Sources and transport of nitrogen in arid urban watersheds
Abstract
Urban watersheds are often sources of nitrogen (N) to downstream systems, contributing to poor water quality. However, it is unknown which components (e.g., land cover and stormwater infrastructure type) of urban watersheds contribute to N export and which may be sites of retention. In this study we investigated which watershed characteristics control N sourcing, biogeochemical processing of nitrate (NO3–) during storms, and the amount of rainfall N that is retained within urban watersheds. We used triple isotopes of NO3– (δ15N, δ18O, and Δ17O) to identify sources and transformations of NO3– during storms from 10 nested arid urban watersheds that varied in stormwater infrastructure type and drainage area. Stormwater infrastructure and land cover—retention basins, pipes, and grass cover—dictated the sourcing of NO3– in runoff. Urban watersheds can be strong sinks or sources of N to stormwater depending on the proportion of rainfall that leaves the watershed as runoff, but we found no evidence that denitrification occurred during storms. Our results suggest that watershed characteristics control the sources and transport of inorganic N in urban stormwater but that retention of inorganic N at the timescale of individual runoff events is controlled by hydrologic, rather than biogeochemical, mechanisms.
- Authors:
- Publication Date:
- Research Org.:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1173035
- Report Number(s):
- PNNL-SA-105490
- DOE Contract Number:
- AC05-76RL01830
- Resource Type:
- Journal Article
- Journal Name:
- Environmental Science & Technology, 48(11):6211-6219
- Additional Journal Information:
- Journal Name: Environmental Science & Technology, 48(11):6211-6219
- Country of Publication:
- United States
- Language:
- English
- Subject:
- nitrate triple isotopes; arid-urban watersheds; nitrate sources
Citation Formats
Hale, Rebecca L., Turnbull, Laura, Earl, Stevan, Grimm, Nancy B., Riha, Krystin M., Michalski, Greg, Lohse, Kathleen, and Childers, Daniel L. Sources and transport of nitrogen in arid urban watersheds. United States: N. p., 2014.
Web. doi:10.1021/es501039t.
Hale, Rebecca L., Turnbull, Laura, Earl, Stevan, Grimm, Nancy B., Riha, Krystin M., Michalski, Greg, Lohse, Kathleen, & Childers, Daniel L. Sources and transport of nitrogen in arid urban watersheds. United States. https://doi.org/10.1021/es501039t
Hale, Rebecca L., Turnbull, Laura, Earl, Stevan, Grimm, Nancy B., Riha, Krystin M., Michalski, Greg, Lohse, Kathleen, and Childers, Daniel L. 2014.
"Sources and transport of nitrogen in arid urban watersheds". United States. https://doi.org/10.1021/es501039t.
@article{osti_1173035,
title = {Sources and transport of nitrogen in arid urban watersheds},
author = {Hale, Rebecca L. and Turnbull, Laura and Earl, Stevan and Grimm, Nancy B. and Riha, Krystin M. and Michalski, Greg and Lohse, Kathleen and Childers, Daniel L.},
abstractNote = {Urban watersheds are often sources of nitrogen (N) to downstream systems, contributing to poor water quality. However, it is unknown which components (e.g., land cover and stormwater infrastructure type) of urban watersheds contribute to N export and which may be sites of retention. In this study we investigated which watershed characteristics control N sourcing, biogeochemical processing of nitrate (NO3–) during storms, and the amount of rainfall N that is retained within urban watersheds. We used triple isotopes of NO3– (δ15N, δ18O, and Δ17O) to identify sources and transformations of NO3– during storms from 10 nested arid urban watersheds that varied in stormwater infrastructure type and drainage area. Stormwater infrastructure and land cover—retention basins, pipes, and grass cover—dictated the sourcing of NO3– in runoff. Urban watersheds can be strong sinks or sources of N to stormwater depending on the proportion of rainfall that leaves the watershed as runoff, but we found no evidence that denitrification occurred during storms. Our results suggest that watershed characteristics control the sources and transport of inorganic N in urban stormwater but that retention of inorganic N at the timescale of individual runoff events is controlled by hydrologic, rather than biogeochemical, mechanisms.},
doi = {10.1021/es501039t},
url = {https://www.osti.gov/biblio/1173035},
journal = {Environmental Science & Technology, 48(11):6211-6219},
number = ,
volume = ,
place = {United States},
year = {Tue Jun 03 00:00:00 EDT 2014},
month = {Tue Jun 03 00:00:00 EDT 2014}
}