Electronic supplement Nestler A, Berglund M, Accoe F, Duta S, Xue, D, Boeckx P, Taylor P. Isotopes for improved management of nitrate pollution in aqueous resources: review of surface water field studies. Environmental Science and Pollution Research. doi: 10.1007/s11356-010-0422-z Table 1: Transformation processes in surface waters affecting the isotope signature of nitrate indicated by the enrichment factor1) Process Study Enrichment factor 1) (‰) References N-isotopes O-isotopes Riparian with grasses (surface -16.6 to -6.2 Dhondt et al. 2003 denitrification flow) and nitrate uptake by plants Reed belt of a lake (surface -5.12 to -1.03 Fukuhara et al. 2007 flow) culture -28.6 Barford et al. 1999 culture -30 -15 Oleros 1984 culture, river -3.6 to -1.5 to Sebilo et al. 2003 water, benthic culture, river -18 -10 Sebilo et al. 2003 water, riparian water, central -25 to -22 Brandes et al. 1998 Arabian Sea water, eastern tropical North -30 to -25 Brandes et al. 1998 Pacific water, eastern tropical North -40 to -30 Cline and Kaplan 1975 denitrification, Pacific Ocean water anaerobic hypolimnion, -11.2 -6.6 Lehmann et al. 2003 eutrophic Lake Lugano water, North -35 to -30 Sutka et al. 2004 Pacific marine water column, Santa -25 Sigman et al. 2003 Barbara Basin marine sediment, Santa -1.5 Sigman et al. 2003 Barbara Basin eastern tropical Voss et al. 2001 North Pacific -22.5 Ocean denitrification, - 3 to 0 Brandes and Devol 2002 marine sediment Ise Bay, Japan ~ -1 Sugimoto et al. 2008 Continuation table 1 Transformation processes in surface waters affecting the isotope signature of nitrate indicated by the enrichment factor1) Process Study Enrichment factor 1) (‰) References N-isotopes O-isotopes nitrification culture, Casciotti et al. 2003 different -38.2 to -14.2 nitrifying strains -15.8 Freyer and Aly 1975 -28 to -12 Mariotti et al. 1982 marine water. Horrigan et al. 1990 Chesapeake -17 to -12 Bay Seine River -20 Sebilo et al. 2006 marine water, Sugimoto et al. 2008 -24.5 Ise Bay, Japan marine water, Sugimoto et al. 2009 -25 to -15 Ise Bay, Japan nitrate culture, Granger et al. 2009 assimilation prokaryotic < -5 phytoplankton strains Culture, Granger et al. 2009 eukaryotic -8 to -5 phytoplankton strains culture, two Montoya and McCarthy -12.1 to -9 diatom species 1995 culture, four Montoya and McCarthy flagellate -3.2 to -0.9 1995 species
culture, algae -13.5 to -6.0 Needoba et al. 2004 Thalassiosira depending on weissflogii, the grow conditions Skeletonema Pennock et al. 1996 costatum, -9 0.7 culture Continuation table: 1 Transformation processes in surface waters affecting the isotope signature of nitrate indicated by the enrichment factor1) Process Study Enrichment factor 1) (‰) References N-isotopes O-isotopes nitrate artificial Needoba et al. 2003 assimilation seawater, 12 species of -6.2 to -2.2 marine phytoplankton culture -23 to -1 Wada and Hattori 1978 Thalassiosira Waser et al. 1998a -5.2 ± 0.2 pseudonana culture, 4 Waser et al. 1998b different -5 to -4 diatoms water, North Altabet et al. 1991 -9 to -8 Atlantic Ocean phytoplankton, Altabet et al. 1999 Eastern North -5 Pacific Southern Ocean -6 to -4 Sigman et al. 1999 field estimate ~ -6 Waser et al. 1998a -30 Vogel et al. 1981 1) enrichment of the heavier isotope in the environment due to fractionation processes can be described with the isotopic fractionation factor by the relation of the rate constants k of the transformation processes respectively, by the isotopic enrichment factor ε
k15 k18 N or O and 1000( 1) k 14 k N 16O Data from Sebilo et al. (2006) and references stated in the table Table 2: Transformation processes in soils which affect the isotope signature of nitrate indicated by the isotope enrichment factor Enrichment factor Process Study (‰) References N-isotopes ammonia -27 to -20 Hoegberg 1997 volatilization -60 to -40 Robinson 2001 nitrate uptake Mariotti et al. -0.25 ± -0.10 by plants 1980 hydroponic systems Dhondt et al. -4.4 ± 0.3 2003
N2-fixation -6 to 0 Robinson 2001 -2 to +2 Hoegberg 1997 denitrification boreal forest Menyailo and - -29 to -24 NO3 to N2O Hungate 2006 Denitrification boreal forest Menyailo and -9.8 to -6.3 N2O to N2 Hungate 2006 denitrification anaerobic soil slurries Dhondt et al. -22.5 0.6 2003 laboratory, soil at 20C Mariotti et al. -29.4 ± 2.4 1981 laboratory, soil at 30C Mariotti et al. -24.6 ± 0.9 1981 laboratory soil, topsoil Pintar et al. -7.60 1.28 2008 laboratory soil, subsoil) Pintar et al. -34.91 1.77 2008 laboratory soil 20C, Mathieu et al. -23.3 2.0 2007 constructed wetland Søvik et al. -5.9 to -2.5 2008 wetland (field) -2.5 Lund et al. 1999 nitrification -8 to -4 Garten 1993 sites across Europe Emmett et al. -8 to -1 1998 Garten and van -10 to -1 Miegroet 1994 Pardo et al. -10 to -1 2004 cultures of Nitrosomonas Mariotti et al. -34.7±2.5 europaea 1981 ammonification -5 to 0 Robinson 2001 Ion exchange -8 to -1 Hubener 1986 1) enrichment of the heavier isotope in the environment due to fractionation processes can be described with the isotopic fractionation factor by the relation of the rate constants k of the transformation processes respectively, by the isotopic enrichment factor ε
k15 k18 N or O and 1000( 1) k 14 k N 16O Table 3: Nitrate isotope data (in ‰) reported in forested watersheds studies
Atmospheric deposition Soil water Surface water δ15N δ18O δ15N δ18O δ15N δ18O mean min max mean min max mean min max mean min max mean min max mean min max Five forested watersheds in the Connecticut River watershed; source: microbial nitrate (82–100%) (Barnes et al. 2008) -2 -5 +1 +71 +50 +84 -4 +10 0 +6 Watershed at baseflow (1st. row) and peakflow (2nd row) in upper Spring Creek; source: predominately was a mixture of event atmospheric and older stored soil sources at peakflow (Buda and DeWalle 2009) +0.2 -5.6 +5.0 +44.3 +11.9 +70.0 +1.4 0.0 +2.6 +4.9 +0.4 +13.6 +1.3 +0.3 +2.9 +15.9 +11.3 +2.6 Two forested watersheds in the Catskill Mountains, New York, source: mainly nitrification, during a high-flow event precipitation major source (Burns and Kendall 2002) -0.2 +50.5 +35 +70 +1.5* +16.1* +13.2* +16.0* +2.3 -1 +4 +17.7 Biscuit Brook (1.row) and Buck Creek (2.row); source: mainly nitrification of soil N (Burns et al. 2009) +1.9 +2.8 -0.8 -3.5 +1.9 +77.8 +69.7 +85.9 +1.9 +3.8 Two watersheds in the Adirondack Mountains, New York, source watershed-derived source, atmospheric contributions relatively minor (Campbell et al. 2006) -3 3 +54 +82 -1 +3 0 +19 +1 0 +2 0 +14 7 to 13 catchments, Upper Susquehanna River Basin, New York; sources: mainly microbial nitrate, some March sample snowmelt/atmospheric nitrate up to 47% (Goodale et al. 2009) -1 -3 +2 +77 +71 81 -2 +6 +1 -7 +34 Two subwatersheds in Vermont, USA, source: microbial nitrate (Hales et al. 2007) -4.5 +2.0 +46.8 +35.3 +58.3 -10.3 +6.2 +14.5 +10.3 +18.7 +0.3 +3.1 +13.2 +8.9 +17.5 *nitrate derived by incubation of soil Table to be continued next page Continuation Table 3: Nitrate isotope data (in ‰) reported in forested watersheds studies
Atmospheric deposition Soil water Surface water δ15N δ18O δ15N δ18O δ15N δ18O mean min max mean min max mean min max mean min max mean min max mean min max Six forested watersheds; source: mainly nitrification (Mayer et al. 2002) +3.6 +7.8 +11.7 +18.5 Sleepers River Research Watershed in Vermont; sources: atmospheric nitrate, soil nitrate, suggesting a mix of snowmelt, soil water, and groundwater (Ohte et al. 2004) +90 -7 +70 -8 +18 three watersheds in the White Mountains, New Hampshire, USA, source: 55-100% nitrification in the watershed (Pardo et al. 2004) -2 -5 +2 +62 +44 +77 0 -3 +6 +18 +12 +33 Subcatchment of Arbutus Watershed in the Huntington Wildlife Forest, Adirondack Region, New York, USA, source: nitrification (and groundwater) (Piatek et al. 2005) -6 +4 +41 +73 +7 +17 +10 +6 +16 +10 +6 +16 +1 -6 +3 Western Oldman River, Canada (data of the western tributaries in the same range, with 2 exceptions); mainly soil nitrification (Rock and Mayer 2004) 2.7 -1 5.5 -1.0 -3.7 2.2 3 rivers in Watershed 9 at the Sleepers River Research Watershed, Danville VT, USA; sources: atmospheric sources, nitrified sources (Sebestyen et al. 2008) -4 +3 +76 +101 -12 +7 -11 +71 0 +7 -5 +43 (Schiff et al. 2002) -5 -2 +42 +30 +54 -5 -2 +5 +24 0 +5 Two catchments in the Turkey Lakes Watershed source: mainly nitrification (Spoelstra et al. 2007) -2 -4 +1 +50 +35 +59 +1 +6 +5 +20 +1 +6 +3 +15 Mid-Appalachian forested watersheds; sources: (Williard et al. 2001) +57 +17 +76 +8* 0* +14* +2 +22 Table 4: Nitrate isotope data (in ‰) reported in agricultural watershed studies
Sources Surface water Reference δ15N δ18O δ15N δ18O Watershed/rive analyzed mean min max mean min max mean min max mean min max r/lake or mean SD or mean SD or mean SD or mean SD Tile drain out 1 +9.6 +12.6 +4.1 +6.6 Tile drain out 2 +4.3 +10.9 +3.4 +14.6 Warnow River, Ditch 1 +8.6 +11.9 +4.2 +5.2 Deutsch et al. Germany, +8.2 +9.6 +5.3 +6.5 2006 Ditch 2 +7.4 +9.3 +3.6 +6.5 Europe Groundwater -0.5 +3.5 +0.5 +2.5 Atm. deposition +0.4 +3.7 +49.1 +60.7 rain +0.5 Mineral fertilizer +1.5 Prescott Kellman and Soil org. matter +4 +9 Drainage Basin/ +10 +19 Hillaire-Marcel Prescott river, Hog manure +12.5 2003 Canada Tile drain 4 +11 +17 Branch ~+10 ~+26 1000-m reach, 3.63 4.63 7.87 0.12 Hermitage Interstial water 8.00 7.43 7.20 0.10 stream, France - 9.97 10.6 5.63 0.38 upstream Lefebvre et al. 1000-m reach, 2007 3.97 4.09 8.00 0.10 Hermitage Groundwater 7.70 2.57 7.35 0.05 stream, France - -1.5 4.91 downstream 6.10 0.40 *classified as agricultural land use (> 75%); **Oldman River Basin Table 5: Nitrate isotope data (in ‰) reported in urban and mixed watershed studies Sources Surface water Reference δ15N δ18O δ15N δ18O Watershed/ analyzed mean min max mean min max mean min max mean min max river/lake or mean SD or mean SD or mean SD or mean SD Atm. deposition -4 +52.1 Pintloopd) +9.8 +14.6 +4.6 +10.3 Accoe et al. a) e) 2008 Manure (Ntotal) +11.7 +13.1 Hirkenloop +11 +13.1 +4.7 +5.0 Greenhouse +2.9 +22.1 Koningsvenloop +14.1 17.5 +7.4 +9.2 discharge b) f)
KNO3 fertilizer 0.5 +25.2 Leyloop – +11.6 +16.5 +6.8 +12.2 Ossevenneloopg)
Ca(NO3) 1.4 +24.4 Kasteelbeek- +8.3 +18.7 +6.3 +17.5 fertilizer Heesbeekh) Sewage c) 11.3 9.4 Sluiskensvijver +10.1 +12.2 +5.5 +12.2 Sewage +4.7 +17.7 -2.2 +4.4 Quinnipiac and ~+1 ~+13 Anisfeld et al. Naugatuck 2007 Atm. deposition -2.4 2.5 70.5 6.0 Rivers Microbial nitrate 4.6 1.0 0.9 0.8 precipitation -6.8 +3.0 +33.3 +55.9 Upper Illinois +7.1 +11.7 +0.9 +9.7 Panno et al. Treated +3.6 +15.5 0.6 8.1 River 2008 wastewater Agricultural +6.0 +12.4 +6.9 14.8 Lower Illinois +5.0 +14.4 +5.8 +9.5 tiles River Agricultural soil +6.5 +7.3 +7.4 +10.4 water Shallow +3.8 14.1 +5.2 +11.6 Fox River +3.49 <0.01 +4.69 +7.9 +6.6 +11.4 Groundwater Pristine soil +1.0 +3.1 +2.6 +9.3 Shangamon +3.88 +5.0 +22.5 +7.7 +6.0 +18.5 water river Livestock +7.1 +18.8 +7.1 +18.8 manure 11B of sources a) +15.5; b) 0.7c) +7.2 (another sewage sample: -1.5) MAP sampling point / 11B of sample: d) 79670 / +19.7; e) 79700/ +17.3; f) 71200 / +14.5; g) 85400 /+19.2 to 19.7 h) 69000/ +16.4; i) 82870 / +21.3 References Accoe F, Berglund M, Duta S, Hennessy C, Taylor P, Hoof KV, Smedt SD (2008) Source apportionment of nitrate pollution in surface water using stable isotopes of N and O in nitrate and B. European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Geel, EUR 23425 EN Altabet MA, Deuser WG, Honjo S, Stienen C (1991) Seasonal and depth-related changes in the source of sinking particles in the North Atlantic. Nature 354: 136-139 Altabet MA, Pilskaln C, Thunell R, Pride C, Sigman D, Chavez F, Francois R (1999) The nitrogen isotope biogeochemistry of sinking particles from the margin of the Eastern North Pacific. Deep Sea Research Part I: Oceanographic Research Papers 46: 655-679 Anisfeld SC, Barnes RT, Altabet MA, Wu T (2007) Isotopic Apportionment of Atmospheric and Sewage Nitrogen Sources in Two Connecticut Rivers. Environ Sci Technol 41: 6363-6369 Barford CC, Montoya JP, Altabet MA, Mitchell R (1999) Steady-State Nitrogen Isotope Effects of
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12 Pardo LH, Kendall C, Pett-Ridge J, Chang CCY (2004) Evaluating the source of streamwater nitrate using delta 15N and delta 18O in nitrate in two watersheds in New Hampshire, USA. Hydrological Processes 18: 2699-2712 Pennock JR, Velinsky DJ, Ludlam JM, Sharp JH, Fogel ML (1996) Isotopic fractionation of ammonium and nitrate during uptake by Skeletonema costatum: Implications for δ15N dynamics under bloom conditions. Limnology and Oceanography 41: 451-459 Piatek KB, Mitchell MJ, Silva SR, Kendall C (2005) Sources of Nitrate in Snowmelt Discharge: Evidence From Water Chemistry and Stable Isotopes of Nitrate. Water, Air, & Soil Pollution 165: 13-35 Pintar M, Bolta SV, Lobnik F (2008) Nitrogen isotope enrichment factor as an indicator of denitrification potential in top and subsoil in the ApaÄe Valley, Slovenia. Australian Journal of Soil Research 46: 719-726 Robinson D (2001) 15N as an integrator of the nitrogen cycle. Trends in Ecology & Evolution 16: 153-162 Rock L, Mayer B (2004) Isotopic assessment of sources of surface water nitrate within the Oldman River Basin, Southern Alberta, Canada. Water, Air, and Soil Pollution: Focus 4: 545-562 Schiff SL, Devito KJ, Elgood RJ, McCrindle PM, Spoelstra J, Dillon P (2002) Two adjacent forested catchments: Dramatically different NO3− export. Water Resour Res 38: 1292 Sebestyen SD, Boyer EW, Shanley JB, Kendall C, Doctor DH, Aiken GR, Ohte N (2008) Sources, transformations, and hydrological processes that control stream nitrate and dissolved organic matter concentrations during snowmelt in an upland forest. Water Resour Res 44: W12410 Sebilo M, Billen G, Grably M, Mariotti A (2003) Isotopic composition of nitrate-nitrogen as a marker of riparian and benthic denitrification at the scale of the whole Seine River system. Biogeochemistry 63: 35-51 Sebilo M, Billen G, Mayer B, Billiou D, Grably M, Garnier J, Mariotti A (2006) Assessing Nitrification and Denitrification in the Seine River and Estuary Using Chemical and Isotopic Techniques. Ecosystems 9: 564-577 Sigman DM, Altabet MA, McCorkle DC, Francois R, Fischer G (1999) The δ15N of nitrate in the southern ocean: Consumption of nitrate in surface waters. Global Biogeochem Cycles 13: 1149- 1166 Sigman DM, Robinson R, Knapp AN, van Geen A., McCorkle DC, Brandes JA, Thunell RC (2003) Distinguishing between water column and sedimentary denitrification in the Santa Barbara Basin using the stable isotopes of nitrate. Geochem. Geophys. Geosyst. 4: 1040 Søvik AK, Mørkved PT (2008) Use of stable nitrogen isotope fractionation to estimate denitrification in small constructed wetlands treating agricultural runoff. Science of The Total Environment 392: 157-165 Spoelstra J, Schiff SL, Hazlett PW, Jeffries DS, Semkin RG (2007) The isotopic composition of nitrate produced from nitrification in a hardwood forest floor. Geochimica et Cosmochimica Acta 71: 3757-3771 Sugimoto R, Kasai A, Miyajima T, Fujita K (2008) Nitrogen isotopic discrimination by water column nitrification in a shallow coastal environment. Journal of Oceanography 64: 39-48
13 Sugimoto R, Kasai A, Miyajima T, Fujita K (2009) Controlling factors of seasonal variation in the nitrogen isotope ratio of nitrate in a eutrophic coastal environment. Estuarine, Coastal and Shelf Science 85: 231-240 Sutka RL, Adams GC, Ostrom NE, Ostrom PH (2008) Isotopologue fractionation during N2O production by fungal denitrification. Rapid Communications in Mass Spectrometry 22: 3989-3996 Vogel JC, Talma AS, Heaton THE (1981) Gaseous nitrogen as evidence for denitrification in groundwater. Journal of Hydrology 50: 191-200 Voss M, Dippner JW, Montoya JP (2001) Nitrogen isotope patterns in the oxygen-deficient waters of the Eastern Tropical North Pacific Ocean. Deep Sea Research Part I: Oceanographic Research Papers 48: 1905-1921 Wada E, Hattori A (1978) Nitrogen isotope effects in the assimilation of inorganic nitrogenous compounds by marine diatoms. Geomicrobiology Journal 1: 85 - 101 Waser NA, Yin K, Yu Z, Tada K, Harrison PJ, Turpin DH, Calvert SE (1998) Nitrogen isotope fractionation during nitrate, ammonium and urea uptake by marine diatoms and coccolithophores under various conditions of N availability. Marine Ecology Progress Series 169: 29-41 Waser NA, Yin K, Yu Z, Tada K, Harrison PJ, Turpin DH, Calvert SE (1998) Nitrogen isotope fractionation during nitrate, ammonium and urea uptake by marine diatoms and coccolithophores under various conditions of N availability. Marine Ecology Progress Series 169: 29-41 Waser NA, Yin K, Yu Z, Tada K, Harrison PJ, Turpin DH, Calvert SE (1998b) Nitrogen isotope fractionation during nitrate, ammonium and urea uptake by marine diatoms and coccolithophores under various conditions of N availability. Marine Ecology Progress Series 169: 29-41 Waser NAD, Harrison PJ, Nielsen B, Calvert SE, Turpin DH (1998a) Nitrogen isotope fractionation during the uptake and assimilation of nitrate, nitrite, ammonium, and urea by a marine diatom. Limnology and Oceanography 43: 215-224 Williard KWJ, DeWalle DR, Edwards PJ, Sharpe WE (2001) 18O isotopic separation of stream nitrate sources in mid-Appalachian forested watersheds. Journal of Hydrology 252: 174-188
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