Sources of nitrate in rivers draining sixteen watersheds in the northeastern U.S. Isotopic constraints

Bernhard Mayer, Elizabeth Weeks Boyer, Christine Goodale, Norbert A. Jaworski, Nico Van Breemen, Robert W. Howarth, Sybil Seitzinger, Gilles Billen, Kate Lajtha, Knute Nadelhoffer, Douwe Van Dam, Leo J. Hetling, Miloslav Nosal, Keith Paustian

Research output: Contribution to journalArticle

306 Citations (Scopus)

Abstract

The feasibility of using nitrogen and oxygen isotope ratios of nitrate (NO3-) for elucidating sources and transformations of riverine nitrate was evaluated in a comparative study of 16 watersheds in the northeastern U.S.A. Stream water was sampled repeatedly at the outlets of the watersheds between January and December 1999 for determining concentrations, δ15N values, and δ18 values of riverine nitrate. In conjunction with information about land use and nitrogen fluxes, δ15Nnitrate and δ18Onitrate values provided mainly information about sources of riverine nitrate. In predominantly forested watersheds, riverine nitrate had mean concentrations of less than 0.4 mg NO3--N L-1, δ15Nnitrate value s of less than +5‰, and δ18Onitrate values between +12 and + 19‰. This indicates that riverine nitrate was almost exclusively derived from soil nitrification processes with potentially minor nitrate contributions from atmospheric deposition in some catchments. In watersheds with significant agricultural and urban land use, concentrations of riverine nitrate were as high as 2.6 mg NO3--N L-1 with δ15Nnitrate values between +5 and +8‰ and δ18Onitrate values generally below +15‰. Correlations between nitrate concentrations, δ15Nnitrate values, and N fluxes suggest that nitrate in waste water constituted a major and nitrate in manure a minor additional source of riverine nitrate. Atmospheric nitrate deposition or nitrate-containing fertilizers were not a significant source of riverine nitrate in watersheds with significant agricultural and urban land use. Although complementary studies indicate that in-stream denitrification was significant in all rivers, the isotopic composition of riverine nitrate sampled at the outlet of the 16 watersheds did not provide evidence for denitrification in the form of elevated δ15Nnitrate and δ18Onitrate values. Relatively low isotopic enrichment factors for nitrogen and oxygen during in-stream denitrification and continuous admixture of nitrate from the above-described sources are thought to be responsible for this finding.

Original languageEnglish (US)
Pages (from-to)171-197
Number of pages27
JournalBiogeochemistry
Volume57-58
DOIs
StatePublished - Jul 27 2002

Fingerprint

Watersheds
Nitrates
Rivers
watershed
nitrate
river
Denitrification
Land use
denitrification
draining
land use
Nitrogen
Nitrogen Isotopes
Oxygen Isotopes
Fluxes
oxygen isotope ratio
Nitrification
Manures
nitrogen
Fertilizers

All Science Journal Classification (ASJC) codes

  • Environmental Chemistry
  • Water Science and Technology
  • Earth-Surface Processes

Cite this

Mayer, B., Boyer, E. W., Goodale, C., Jaworski, N. A., Van Breemen, N., Howarth, R. W., ... Paustian, K. (2002). Sources of nitrate in rivers draining sixteen watersheds in the northeastern U.S. Isotopic constraints. Biogeochemistry, 57-58, 171-197. https://doi.org/10.1023/A:1015744002496
Mayer, Bernhard ; Boyer, Elizabeth Weeks ; Goodale, Christine ; Jaworski, Norbert A. ; Van Breemen, Nico ; Howarth, Robert W. ; Seitzinger, Sybil ; Billen, Gilles ; Lajtha, Kate ; Nadelhoffer, Knute ; Van Dam, Douwe ; Hetling, Leo J. ; Nosal, Miloslav ; Paustian, Keith. / Sources of nitrate in rivers draining sixteen watersheds in the northeastern U.S. Isotopic constraints. In: Biogeochemistry. 2002 ; Vol. 57-58. pp. 171-197.
@article{865c372ac3454dc895c00dcdc11add7f,
title = "Sources of nitrate in rivers draining sixteen watersheds in the northeastern U.S.: Isotopic constraints",
abstract = "The feasibility of using nitrogen and oxygen isotope ratios of nitrate (NO3-) for elucidating sources and transformations of riverine nitrate was evaluated in a comparative study of 16 watersheds in the northeastern U.S.A. Stream water was sampled repeatedly at the outlets of the watersheds between January and December 1999 for determining concentrations, δ15N values, and δ18 values of riverine nitrate. In conjunction with information about land use and nitrogen fluxes, δ15Nnitrate and δ18Onitrate values provided mainly information about sources of riverine nitrate. In predominantly forested watersheds, riverine nitrate had mean concentrations of less than 0.4 mg NO3--N L-1, δ15Nnitrate value s of less than +5‰, and δ18Onitrate values between +12 and + 19‰. This indicates that riverine nitrate was almost exclusively derived from soil nitrification processes with potentially minor nitrate contributions from atmospheric deposition in some catchments. In watersheds with significant agricultural and urban land use, concentrations of riverine nitrate were as high as 2.6 mg NO3--N L-1 with δ15Nnitrate values between +5 and +8‰ and δ18Onitrate values generally below +15‰. Correlations between nitrate concentrations, δ15Nnitrate values, and N fluxes suggest that nitrate in waste water constituted a major and nitrate in manure a minor additional source of riverine nitrate. Atmospheric nitrate deposition or nitrate-containing fertilizers were not a significant source of riverine nitrate in watersheds with significant agricultural and urban land use. Although complementary studies indicate that in-stream denitrification was significant in all rivers, the isotopic composition of riverine nitrate sampled at the outlet of the 16 watersheds did not provide evidence for denitrification in the form of elevated δ15Nnitrate and δ18Onitrate values. Relatively low isotopic enrichment factors for nitrogen and oxygen during in-stream denitrification and continuous admixture of nitrate from the above-described sources are thought to be responsible for this finding.",
author = "Bernhard Mayer and Boyer, {Elizabeth Weeks} and Christine Goodale and Jaworski, {Norbert A.} and {Van Breemen}, Nico and Howarth, {Robert W.} and Sybil Seitzinger and Gilles Billen and Kate Lajtha and Knute Nadelhoffer and {Van Dam}, Douwe and Hetling, {Leo J.} and Miloslav Nosal and Keith Paustian",
year = "2002",
month = "7",
day = "27",
doi = "10.1023/A:1015744002496",
language = "English (US)",
volume = "57-58",
pages = "171--197",
journal = "Biogeochemistry",
issn = "0168-2563",
publisher = "Springer Netherlands",

}

Mayer, B, Boyer, EW, Goodale, C, Jaworski, NA, Van Breemen, N, Howarth, RW, Seitzinger, S, Billen, G, Lajtha, K, Nadelhoffer, K, Van Dam, D, Hetling, LJ, Nosal, M & Paustian, K 2002, 'Sources of nitrate in rivers draining sixteen watersheds in the northeastern U.S. Isotopic constraints', Biogeochemistry, vol. 57-58, pp. 171-197. https://doi.org/10.1023/A:1015744002496

Sources of nitrate in rivers draining sixteen watersheds in the northeastern U.S. Isotopic constraints. / Mayer, Bernhard; Boyer, Elizabeth Weeks; Goodale, Christine; Jaworski, Norbert A.; Van Breemen, Nico; Howarth, Robert W.; Seitzinger, Sybil; Billen, Gilles; Lajtha, Kate; Nadelhoffer, Knute; Van Dam, Douwe; Hetling, Leo J.; Nosal, Miloslav; Paustian, Keith.

In: Biogeochemistry, Vol. 57-58, 27.07.2002, p. 171-197.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Sources of nitrate in rivers draining sixteen watersheds in the northeastern U.S.

T2 - Isotopic constraints

AU - Mayer, Bernhard

AU - Boyer, Elizabeth Weeks

AU - Goodale, Christine

AU - Jaworski, Norbert A.

AU - Van Breemen, Nico

AU - Howarth, Robert W.

AU - Seitzinger, Sybil

AU - Billen, Gilles

AU - Lajtha, Kate

AU - Nadelhoffer, Knute

AU - Van Dam, Douwe

AU - Hetling, Leo J.

AU - Nosal, Miloslav

AU - Paustian, Keith

PY - 2002/7/27

Y1 - 2002/7/27

N2 - The feasibility of using nitrogen and oxygen isotope ratios of nitrate (NO3-) for elucidating sources and transformations of riverine nitrate was evaluated in a comparative study of 16 watersheds in the northeastern U.S.A. Stream water was sampled repeatedly at the outlets of the watersheds between January and December 1999 for determining concentrations, δ15N values, and δ18 values of riverine nitrate. In conjunction with information about land use and nitrogen fluxes, δ15Nnitrate and δ18Onitrate values provided mainly information about sources of riverine nitrate. In predominantly forested watersheds, riverine nitrate had mean concentrations of less than 0.4 mg NO3--N L-1, δ15Nnitrate value s of less than +5‰, and δ18Onitrate values between +12 and + 19‰. This indicates that riverine nitrate was almost exclusively derived from soil nitrification processes with potentially minor nitrate contributions from atmospheric deposition in some catchments. In watersheds with significant agricultural and urban land use, concentrations of riverine nitrate were as high as 2.6 mg NO3--N L-1 with δ15Nnitrate values between +5 and +8‰ and δ18Onitrate values generally below +15‰. Correlations between nitrate concentrations, δ15Nnitrate values, and N fluxes suggest that nitrate in waste water constituted a major and nitrate in manure a minor additional source of riverine nitrate. Atmospheric nitrate deposition or nitrate-containing fertilizers were not a significant source of riverine nitrate in watersheds with significant agricultural and urban land use. Although complementary studies indicate that in-stream denitrification was significant in all rivers, the isotopic composition of riverine nitrate sampled at the outlet of the 16 watersheds did not provide evidence for denitrification in the form of elevated δ15Nnitrate and δ18Onitrate values. Relatively low isotopic enrichment factors for nitrogen and oxygen during in-stream denitrification and continuous admixture of nitrate from the above-described sources are thought to be responsible for this finding.

AB - The feasibility of using nitrogen and oxygen isotope ratios of nitrate (NO3-) for elucidating sources and transformations of riverine nitrate was evaluated in a comparative study of 16 watersheds in the northeastern U.S.A. Stream water was sampled repeatedly at the outlets of the watersheds between January and December 1999 for determining concentrations, δ15N values, and δ18 values of riverine nitrate. In conjunction with information about land use and nitrogen fluxes, δ15Nnitrate and δ18Onitrate values provided mainly information about sources of riverine nitrate. In predominantly forested watersheds, riverine nitrate had mean concentrations of less than 0.4 mg NO3--N L-1, δ15Nnitrate value s of less than +5‰, and δ18Onitrate values between +12 and + 19‰. This indicates that riverine nitrate was almost exclusively derived from soil nitrification processes with potentially minor nitrate contributions from atmospheric deposition in some catchments. In watersheds with significant agricultural and urban land use, concentrations of riverine nitrate were as high as 2.6 mg NO3--N L-1 with δ15Nnitrate values between +5 and +8‰ and δ18Onitrate values generally below +15‰. Correlations between nitrate concentrations, δ15Nnitrate values, and N fluxes suggest that nitrate in waste water constituted a major and nitrate in manure a minor additional source of riverine nitrate. Atmospheric nitrate deposition or nitrate-containing fertilizers were not a significant source of riverine nitrate in watersheds with significant agricultural and urban land use. Although complementary studies indicate that in-stream denitrification was significant in all rivers, the isotopic composition of riverine nitrate sampled at the outlet of the 16 watersheds did not provide evidence for denitrification in the form of elevated δ15Nnitrate and δ18Onitrate values. Relatively low isotopic enrichment factors for nitrogen and oxygen during in-stream denitrification and continuous admixture of nitrate from the above-described sources are thought to be responsible for this finding.

UR - http://www.scopus.com/inward/record.url?scp=10744225107&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=10744225107&partnerID=8YFLogxK

U2 - 10.1023/A:1015744002496

DO - 10.1023/A:1015744002496

M3 - Article

AN - SCOPUS:10744225107

VL - 57-58

SP - 171

EP - 197

JO - Biogeochemistry

JF - Biogeochemistry

SN - 0168-2563

ER -