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Characterising the seasonal cycle of dissolved organic nitrogen using Cefas SmartBuoy high-resolution time-series samples from the southern North Sea

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Abstract

The Cefas SmartBuoy network provides a unique insight into the biogeochemical dynamics of the Northern European shelf seas, particularly the North Sea, through high-resolution automated offshore water sampling. We present total dissolved nitrogen and dissolved organic nitrogen (DON) from the Dowsing SmartBuoy site (53.531° N, 1.053° E) from January to October 2010, the first high resolution seasonal (winter-autumn) cycle of DON from the open North Sea. On top of a refractory background DON concentration of approximately 5 μM, a rapid increase in DON of a further ∼5 μM is observed over the course of the spring bloom. This rapidly produced DON declines at an estimated net decay rate of between 0.6 and 1.8 μM month−1. The slow decay suggests that the majority of the additional DON produced during the spring bloom is of semi-labile nature and has a lifetime of weeks to months. The dataset allows us to tightly constrain the budget for water column nitrogen over the winter, spring and summer of 2010 and clearly demonstrates the ‘sawtooth’ nature of the seasonal cycle of DON in the open North Sea, which has been impossible to resolve with a more traditional ship-based mode of operation. This work highlights the importance of autonomous sampling approaches in better understanding shelf sea biogeochemistry in the future.

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References

  • Agedah EC, Binalaiyifa HE, Ball AS, Nedwell DB (2009) Sources, turnover and bioavailability of dissolved organic nitrogen (DON) in the Colne estuary, UK. Mar Ecol Prog Ser 382:23–33. doi:10.3354/meps07938

    Article  Google Scholar 

  • Asman WA, Harrison RM, Ottley C (1994) Estimation of the net air-sea flux of ammonia over the southern bight of the North Sea. Atmos Environ 28(22):3647–3654. doi:10.1016/1352-2310(94)00192-N

    Article  Google Scholar 

  • Bange HW, Bell TG, Cornejo M, Freing A, Uher G, Upstill-Goddard RC, Zhang G (2009) Memento: a proposal to develop a database of marine nitrous oxide and methane measurements. Environ Chem 6(3):195–197

    Article  Google Scholar 

  • Berman T, Bronk D (2003) Dissolved organic nitrogen: a dynamic participant in aquatic ecosystems. Aquat Microb Ecol 31(1981):279–305. doi:10.3354/ame031279

    Article  Google Scholar 

  • Brandes J, Devol A (2007) New developments in the marine nitrogen cycle. Chem Rev 107(2):577–589. doi:10.1021/cr050377t

    Article  Google Scholar 

  • Brion N, Baeyens W, De Galan S, Elskens M, Laane RW (2004) The North Sea: source or sink for nitrogen and phosphorus to the Atlantic Ocean. Biogeochemistry 68(3):277–296. doi:10.1023/B:BIOG.0000031041.38663.aa

    Article  Google Scholar 

  • Bronk DA (2002) Dynamics of DON. In: Hansell DA, Carlson CA (eds) Biogeochemistry of marine dissolved organic matter. Elsevier Academic Press, San Diego, Chap 5, pp 153–247

  • Bronk DA, See JH, Bradley P, Killberg L (2007) DON as a source of bioavailable nitrogen for phytoplankton. Biogeosciences 4(3):283–296

    Article  Google Scholar 

  • Bushaw KL, Zepp RG, Tarr MA, Schulz-Jander D, Bourbonniere RA, Hodson RE, Miller WL, Bronk DA, Moran MA (1996) Photochemical release of biologically available nitrogen from aquatic dissolved organic matter. Nature 381(6581):404–407

    Article  Google Scholar 

  • Caetano M, Falco M, Vale C, Bebianno MJ (1997) Tidal flushing of ammonium, iron and manganese from inter-tidal sediment pore waters. Mar Chem 58(1–2):203–211

    Article  Google Scholar 

  • Capuzzo (2011) TBC. Biogeochemistry (this issue)

  • Church MJ, Ducklow HW, Karl DM (2002) Multiyear increases in dissolved organic matter inventories at station ALOHA in the North Pacific Subtropical Gyre. Limnol Oceanogr 47(1):1–10

    Article  Google Scholar 

  • Costanza R, D’Arge R, de Groot R, Farber S, Grasso M, Hannon B, Limburg K, Naeem S, O’Neill RV, Paruelo J, Raskin RG, Sutton P, van den Belt M (1997) The value of the world’s ecosystem services and natural capital. Nature 387(6630):253–260. doi:10.1038/387253a0

    Article  Google Scholar 

  • Ducrotoy JP, Elliott M, de Jonge VN (2000) The North Sea. Mar Pollut Bull 41(1–6):5–23. doi:16/S0025-326X(00)00099-0

    Article  Google Scholar 

  • Elliott A, Clarke T, Li Z (1991) Monthly distributions of surface and bottom temperatures in the northwest European shelf seas. Cont Shelf Res 11(5):453–466. doi:16/0278-4343(91)90053-9

    Article  Google Scholar 

  • Eppley RW, Peterson BJ (1979) Particulate organic matter flux and planktonic new production in the deep ocean. Nature 282(5740):677–680. doi:10.1038/282677a0

    Article  Google Scholar 

  • Fitzsimons MF, Millward GE, Revitt DM, Dawit MD (2006) Desorption kinetics of ammonium and methylamines from estuarine sediments: consequences for the cycling of nitrogen. Mar Chem 101(1–2):12–26. doi:16/j.marchem.2005.12.006

    Article  Google Scholar 

  • Greenwood N, Parker ER, Fernand L, Sivyer DB, Weston K, Painting SJ, Kr S (2010) Detection of low bottom water oxygen concentrations in the North Sea; implications for monitoring and assessment of ecosystem health. Biogeosciences 7:1357–1373. doi:10.5194/bg-7-1357-2010

    Article  Google Scholar 

  • Hansell DA (2005) Dissolved organic carbon reference material program. Eos 86(35):318. doi:200510.1029/2005EO350003

    Article  Google Scholar 

  • Hansell DA, Carlson CA (2001) Biogeochemistry of total organic carbon and nitrogen in the sargasso sea: control by convective overturn. Deep Sea Res Part II 48(8–9):1649–1667

    Article  Google Scholar 

  • Holmes RM, Aminot A, Kérouel R, Hooker BE, Peterson BJ (1999) A simple and precise method for measuring ammonium in marine and freshwater ecosystems. Can J Fish Aquat Sci 56:1801–1808. doi:10.1139/cjfas-56-10-1801

    Google Scholar 

  • Hughes C, Kettle AJ, Unazi GA, Weston K, Jones MR, Johnson MT (2010) Seasonal variations in the concentrations of methyl and ethyl nitrate in a shallow freshwater lake. Limnol Oceanogr 55(1):305–314

    Article  Google Scholar 

  • Hydes D, Kelly-Gerreyn B, Le Gall A, Proctor R (1999) The balance of supply of nutrients and demands of biological production and denitrification in a temperate latitude shelf sea—a treatment of the southern North Sea as an extended estuary. Mar Chem 68(1–2):117–131. doi:10.1016/S0304-4203(99)00069-9

    Article  Google Scholar 

  • Jickells T (2005) External inputs as a contributor to eutrophication problems. J Sea Res 54(1):58–69. doi:16/j.seares.2005.02.006

    Article  Google Scholar 

  • Jickells TD (1998) Nutrient biogeochemistry of the coastal zone. Science 281(5374):217–222. doi:10.1126/science.281.5374.217

    Article  Google Scholar 

  • Johnson M, Sanders R, Avgoustidi V, Lucas M, Brown L, Hansell D, Moore M, Gibb S, Liss P, Jickells T (2007) Ammonium accumulation during a silicate-limited diatom bloom indicates the potential for ammonia emission events. Mar Chem 106(1–2):63–75. doi:10.1016/j.marchem.2006.09.006

    Article  Google Scholar 

  • Johnson MT, Liss PS, Bell TG, Lesworth TJ, Baker AR, Hind AJ, Jickells TD, Biswas KF, Woodward EMS, Gibb SW (2008) Field observations of the ocean-atmosphere exchange of ammonia: fundamental importance of temperature as revealed by a comparison of high and low latitudes. Glob Biogeochem Cycles 22:15. doi:200810.1029/2007GB003039

    Article  Google Scholar 

  • Joint I, Pomroy A (1993) Phytoplankton biomass and production in the southern North Sea. Mar Ecol Prog Ser 99(1–2):169–182

    Article  Google Scholar 

  • Kirchman DL (2000) Uptake and regeneration of inorganic nutrients by marine heterotrophic bacteria. In: Kirchman DL (ed) Microbial ecology of the oceans. Wiley, New York, pp 261–289

    Google Scholar 

  • Kirkwood DS (1996) Nutrients: practical notes on their determination in seawater. In: ICES techniques in marine environmental sciences, no. 17. International Council for the Exploration of the Seas, Copenhagen, p 23

  • Kitidis V, Uher G (2008) Photochemical mineralisation of dissolved organic nitrogen. In: Mertens LP (ed) Biological oceanography research trends. Nova Science Publishers, New York, pp 131–156

    Google Scholar 

  • Knapp AN, Sigman DM, Lipschultz F (2005) N isotopic composition of dissolved organic nitrogen and nitrate at the Bermuda Atlantic time-series study site. Glob Biogeocheml Cycles 19:15. doi:200510.1029/2004GB002320

    Article  Google Scholar 

  • Lohse L, Malschaert J, Slomp C, Helder W, Vanraaphorst W (1993) Nitrogen cycling in north sea sediments—interaction of denitrification and nitrification in offshore and coastal areas. Mar Ecol Prog Ser 101(3):283–296

    Article  Google Scholar 

  • Lønborg C, Davidson K, Álvarez Salgado XA, Miller AE (2009) Bioavailability and bacterial degradation rates of dissolved organic matter in a temperate coastal area during an annual cycle. Mar Chem 113(3–4):219–226. doi:10.1016/j.marchem.2009.02.003

    Article  Google Scholar 

  • McCarthy M, Pratum T, Hedges J, Benner R (1997) Chemical composition of dissolved organic nitrogen in the ocean. Nature 390(6656):150–154. doi:10.1038/36535

    Article  Google Scholar 

  • Mills DK, Laane RWPM, Rees JM, Rutgers vander Loeff M, Suylen JM, Pearce DJ, Sivyer DB, Heins C, Platt K, Rawlinson M (2003) Smartbuoy: a marine environmental monitoring buoy with a difference. Elsevier Oceanogr Ser 69(C):311–316

    Article  Google Scholar 

  • Mills DK, Greenwood N, Kröger S, Devlin M, Sivyer DB, Pearce D, Cutchey SJ, Malcolm SJ (2005) New approaches to improve the detection of eutrophication in UK coastal waters. Environ Res Eng Manag 2(32):36–42

    Google Scholar 

  • Moll A (1998) Regional distribution of primary production in the North Sea simulated by a three-dimensional model. J Mar Syst 16(1–2):151–170. doi:16/S0924-7963(97)00104-8

    Article  Google Scholar 

  • Morin J, Morse JW (1999) Ammonium release from resuspended sediments in the laguna madre estuary. Mar Chem 65(1–2):97–110

    Article  Google Scholar 

  • Proctor R, Holt JT, Allen JI, Blackford J (2003) Nutrient fluxes and budgets for the North West European Shelf from a three-dimensional model. Sci Total Environ 314(316):769–785. doi:10.1016/S0048-9697(03)00083-4

    Article  Google Scholar 

  • Queste (2011) TBC. Biogeochemistry (this issue)

  • Simpson KG, Tremblay JE, Gratton Y, Price NM (2008) An annual study of inorganic and organic nitrogen and phosphorus and silicic acid in the southeastern Beaufort Sea. J Geophys Res 113:16. doi:200810.1029/2007JC004462

    Article  Google Scholar 

  • Suratman S, Jickells T, Weston K, Fernand L (2008) Seasonal variability of inorganic and organic nitrogen in the North Sea. Hydrobiologia 610(1):83–98. doi:10.1007/s10750-008-9424-y

    Article  Google Scholar 

  • Suratman S, Weston K, Greenwood N, Sivyer DB, Pearce DJ, Jickells T (2010) High frequency measurements of dissolved inorganic and organic nutrients using instrumented moorings in the southern and central North Sea. Estuar Coast Shelf Sci 87(4):631–639. doi:10.1016/j.ecss.2010.03.001

    Article  Google Scholar 

  • Taylor BW, Keep CF, Hall RO, Koch BJ, Tronstad LM, Flecker AS, Ulseth AJ (2007) Improving the fluorometric ammonium method: matrix effects, background fluorescence, and standard additions. J North Am Benthic Soc 26(2):167–177. doi:10.1899/0887-3593(2007)26[167:ITFAMM]2.0.CO;2

    Article  Google Scholar 

  • Van Engeland T (2010) Dissolved organic nitrogen dynamics in coastal ecosystems. PhD thesis, Universiteit Utrecht

  • Van Engeland T, Soetaert K, Knuijt A, Laane R, Middelburg J (2010) Dissolved organic nitrogen dynamics in the North Sea: A time series analysis (1995–2005). Estuar Coast Shelf Sci 89(1):31–42. doi:10.1016/j.ecss.2010.05.009

    Article  Google Scholar 

  • Weston K, Jickells TD, Fernand L, Parker ER (2004) Nitrogen cycling in the southern North Sea: consequences for total nitrogen transport. Estuar Coastal Shelf Scie 59(4):559–573. doi:10.1016/j.ecss.2003.11.002

    Article  Google Scholar 

  • Winther N, Johannessen J (2006) North Sea circulation: Atlantic inflow and its destination. J Geophys Res 111:C12,018. doi:10.1029/2005JC003310

    Article  Google Scholar 

  • Yool A, Martin AP, Fernandez C, Clark DR (2007) The significance of nitrification for oceanic new production. Nature 447(7147):999–1002

    Article  Google Scholar 

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Acknowledgments

Thanks are owed to Liz Claxton, Kimberly Wright and Jim Hunter (University of East Anglia, Norwich) for technical support with TDN analysis. Thanks are also due to the Cefas SmartBuoy team particularly Dave Pearce, Jennie Keable, Tom Hull and Chris Read. The officers and crew of RV Cefas Endeavour and THV Alert are to be commended for their skillful handling of the SmartBuoys. TDN sample analysis was funded by the Natural Environment Research Council of the United Kingdom under grant NE/F017359/1. The SmartBuoy at Dowsing and measurement of core parameters was funded by Defra contract ME5304.

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Johnson, M.T., Greenwood, N., Sivyer, D.B. et al. Characterising the seasonal cycle of dissolved organic nitrogen using Cefas SmartBuoy high-resolution time-series samples from the southern North Sea. Biogeochemistry 113, 23–36 (2013). https://doi.org/10.1007/s10533-012-9738-8

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  • DOI: https://doi.org/10.1007/s10533-012-9738-8

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