Submarine Groundwater Discharge Estimates Using Radium Isotopes and Related Nutrient Inputs into Tauranga Harbour (New Zealand)

  • Benjamin T. Stewart
  • Karin R. Bryan
  • Conrad A. Pilditch
  • Isaac R. Santos
Article

Abstract

Land-based pollutants such as fertilizers and wastewater can infiltrate into aquifers and discharge into surrounding coastal water bodies as submarine groundwater discharge (SGD). Oceanic islands, with a large coast length to land area ratio, may be hot spots of SGD into the global ocean. Although SGD may be a major pathway of dissolved nutrients, carbon and metals to coastal waters, studies have been limited due to the difficulties in measuring this often diffuse process. This study used radium isotopes (223Ra, 224Ra, 226Ra) to investigate SGD and the associated fluxes of nutrients into Tauranga Harbour, New Zealand. We calculated the apparent water mass ages of the harbour to be between ~4.1 and 7.8 days, which was similar to a previous numerical model of ~2–8 days. A 226Ra mass balance was constructed to quantify SGD fluxes at the harbour scale. A minimum SGD flux rate of 0.53 cm day−1 was calculated by using the maximum groundwater end-member value from 22 sample sites. However, using the geometric mean from these samples as a representative end-member, a final value of 2.83 cm day−1 or a flux of 3.09 × 106 m3 day−1 was calculated. These values were between ~1 and 2.8 times greater than all the major river and creeks discharging into the harbour during the sampling period. Due to the higher observed nutrient concentrations in groundwater, the SGD-derived dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON) and total dissolved phosphorus (TDP) fluxes were calculated to be 1.07, 0.87 and 0.05 mmol m2 day−1, respectively. These SGD inputs were ~5 times (for nitrogen) and ~8 times (for phosphorus) greater than the input from surrounding rivers and streams. The average N:P ratio in groundwater samples was 36:1 (which was greatly in excess of the Redfield ratio of 16). The harbour water had a N:P ratio of ~17:1. A positive relationship between radium isotopes and N:P ratios in the harbour further supported the hypothesis that SGD can have major implications for primary production, including recurrent algal bloom events which occur in the harbour. We suggest SGD as a major driver of nutrient dynamics in Tauranga Harbour and potentially other similar coastal lagoon systems and estuaries on oceanic islands.

Keywords

Volcanic island Radium Subterranean estuary Nitrogen Nitrate 

References

  1. Beck, M., and H.J. Brumsack. 2012. Biogeochemical cycles in sediment and water column of the Wadden Sea: the example Spiekeroog Island in a regional context. Ocean & Coastal Management 68: 102–113.CrossRefGoogle Scholar
  2. Beck, A.J., J.P. Rapaglia, J.K. Cochran, and H.J. Bokuniewicz. 2007. Radium mass-balance in Jamaica Bay, NY: evidence for a substantial flux of submarine groundwater. Marine Chemistry 106 (3–4): 419–441.CrossRefGoogle Scholar
  3. Beck, A.J., J.P. Rapaglia, J.K. Cochran, H.J. Bokuniewicz, and S. Yang. 2008. Submarine groundwater discharge to Great South Bay, NY, estimated using Ra isotopes. Marine Chemistry 109 (3–4): 279–291.CrossRefGoogle Scholar
  4. Beck, A.J., A.A. Kellum, J.L. Luek, and M.A. Cochran. 2016. Chemical flux associated with spatially and temporally variable submarine groundwater discharge, and chemical modification in the subterranean estuary at Gloucester Point, VA (USA). Estuaries and Coasts 39 (1): 1–12.CrossRefGoogle Scholar
  5. Beusen, A.H.W., C.P. Slomp, and A.F. Bouwman. 2013. Global land–ocean linkage: direct inputs of nitrogen to coastal waters via submarine groundwater discharge. Environmental Research Letters 8 (3): 034035.CrossRefGoogle Scholar
  6. Briggs, R.M., G.J. Hall, G.R. Harmsworth, A.G. Hollis, B.F. Houghton, G.R. Hughes, M.D. Morgan, and A.R. Whitbread-Edwards. 1996. Geology of the Tauranga area. Department of Earth Sciences Occasional Report, (22). Hamilton: University of Waikato.Google Scholar
  7. Burnett, W.C., et al. 2006. Quantifying submarine groundwater discharge in the coastal zone via multiple methods. Science of the Total Environment 367 (2–3): 498–543.CrossRefGoogle Scholar
  8. Charette, M.A., and E.R. Sholkovitz. 2002. Oxidative precipitation of groundwater-derived ferrous iron in the subterranean estuary of a coastal bay. Geophysical Research Letters 29 (10).Google Scholar
  9. Charette, M.A., K.O. Buesseler, and J.E. Andrews. 2001. Utility of radium isotopes for evaluating the input and transport of groundwater-derived nitrogen to a Cape Cod estuary. Limnology and Oceanography 46 (2): 465–470.CrossRefGoogle Scholar
  10. Charette, M.A., W.S. Moore, and W.C. Burnett. 2008. Uranium-and thorium-series nuclides as tracers of submarine groundwater discharge. Radioactivity in the Environment 13: 155–191.CrossRefGoogle Scholar
  11. Charette, M.A., P.B. Henderson, C.F. Breier, and Q. Liu. 2013. Submarine groundwater discharge in a river-dominated Florida estuary. Marine Chemistry 156 (0): 3–17.CrossRefGoogle Scholar
  12. Cho, H.M., and G. Kim. 2016. Determining groundwater Ra end-member values for the estimation of the magnitude of submarine groundwater discharge using Ra isotope tracers. Geophysical Research Letters 43 (8): 3865–3871.CrossRefGoogle Scholar
  13. Corbett, D., W. Burnett, J.E. Cable, and S.B. Clark. 1998. A multiple approach to the determination of radon fluxes from sediments. Journal of Radioanalytical and Nuclear Chemistry 236: 247–252.CrossRefGoogle Scholar
  14. Cyronak, T., I.R. Santos, D. Erler, and B.D. Eyre. 2013. Groundwater and porewater as a major source of alkalinity to a fringing coral reef lagoon (Muri Lagoon, Cook Islands). Biogeosciences 10 (4): 2467–2480.CrossRefGoogle Scholar
  15. Davis, R.A., and T.R. Healy. 1993. Holocene coastal depositional sequences on a tectonically active setting: southeastern Tauranga Harbour, New Zealand. Sedimentary Geology 84(1–4): 57–69.Google Scholar
  16. Dulaiova, H., and W.C. Burnett. 2008. Evaluation of the flushing rates of Apalachicola Bay, Florida via natural geochemical tracers. Marine Chemistry 109 (3–4): 395–408.CrossRefGoogle Scholar
  17. Eller, K., W. Burnett, L. Fitzhugh, and J. Chanton. 2014. Radium sampling methods and residence times in St. Andrew Bay, Florida. Estuaries and Coasts 37 (1): 94–103.CrossRefGoogle Scholar
  18. Garcia-Solsona, E., J. Garcia-Orellana, P. Masqué, and H. Dulaiova. 2008. Uncertainties associated with 223Ra and 224Ra measurements in water via a delayed coincidence counter (RaDeCC). Marine Chemistry 109 (3–4): 198–219.CrossRefGoogle Scholar
  19. Garcia-Orellana, J., J.K. Cochran, H. Bokuniewicz, S. Yang, and A.J. Beck. 2010. Time-series sampling of 223Ra and 224Ra at the inlet to Great South Bay (New York): a strategy for characterizing the dominant terms in the Ra budget of the bay. Journal of Environmental Radioactivity 101(7): 582–588.Google Scholar
  20. Gleeson, J., I.R. Santos, D.T. Maher, and L. Golsby-Smith. 2013. Groundwater–surface water exchange in a mangrove tidal creek: evidence from natural geochemical tracers and implications for nutrient budgets. Marine Chemistry 156: 27–37.Google Scholar
  21. Gonneea, M.E., P.J. Morris, H. Dulaiova, and M.A. Charette. 2008. New perspectives on radium behavior within a subterranean estuary. Marine Chemistry 109 (3–4): 250–267.CrossRefGoogle Scholar
  22. Hancock, N., Hume, T.M. and Swales, A., 2009. Tauranga harbour sediment study: harbour bed sediments. NIWA.Google Scholar
  23. Heath, R.A. 1985. A review of the physical oceanography of the seas around New Zealand—1982. New Zealand Journal of Marine and Freshwater Research 19 (1): 79–124.CrossRefGoogle Scholar
  24. Howarth, R.W., and R. Marino. 2006. Nitrogen as the limiting nutrient for eutrophication in coastal marine ecosystems: evolving views over three decades. Limnology and Oceanography 51 (1part2): 364–376.CrossRefGoogle Scholar
  25. Hu, C., F.E. Muller-Karger, and P.W. Swarzenski. 2006. Hurricanes, submarine groundwater discharge, and Florida’s red tides. Geophysical Research Letters 33: L11601.CrossRefGoogle Scholar
  26. Hwang, D.W., Y.W. Lee, and G. Kim. 2005. Large submarine groundwater discharge and benthic eutrophication in Bangdu Bay on volcanic Jeju Island, Korea. Limnology and Oceanography 50: 1393–1403.CrossRefGoogle Scholar
  27. Kim, G., Lee, K.K., Park, K.S., Hwang, D.W. and Yang, H.S., 2003. Large submarine groundwater discharge (SGD) from a volcanic island. Geophysical Research Letters, 30(21).Google Scholar
  28. Kim, G., J.W. Ryu, H.S. Yang, and S.T. Yun. 2005. Submarine groundwater discharge (SGD) into the Yellow Sea revealed by Ra-228 and Ra-226 isotopes: implications for global silicate fluxes. Earth and Planetary Science Letters 237 (1–2): 156–166.CrossRefGoogle Scholar
  29. Kim, G., J.W. Ryu, and D.W. Hwang. 2008. Radium tracing of submarine groundwater discharge (SGD) and associated nutrient fluxes in a highly-permeable bed coastal zone, Korea. Marine Chemistry 109 (3): 307–317.CrossRefGoogle Scholar
  30. Kim, G., J.S. Kim, and D.W. Hwang. 2011. Submarine groundwater discharge from oceanic islands standing in oligotrophic oceans: implications for global biological production and organic carbon fluxes. Limnology and Oceanography 56 (2): 673–682.CrossRefGoogle Scholar
  31. Kim, T.H., E. Kwon, I. Kim, S.A. Lee, and G. Kim. 2013. Dissolved organic matter in the subterranean estuary of a volcanic island, Jeju: importance of dissolved organic nitrogen fluxes to the ocean. Journal of Sea Research 78: 18–24.CrossRefGoogle Scholar
  32. Knee, K., and A. Paytan. 2011. 4.08 submarine groundwater discharge: a source of nutrients, metals, and pollutants to the coastal ocean. Treatise on Estuarine and Coastal Science 4: 205–234.CrossRefGoogle Scholar
  33. Knee, K.L., J.H. Street, E.E. Grossman, A.B. Boehm, and A. Paytan. 2010. Nutrient inputs to the coastal ocean from submarine groundwater discharge in a groundwater-dominated system: relation to land use (Kona Coast, Hawai’i, USA). Limnology and Oceanography 55 (3): 1105.CrossRefGoogle Scholar
  34. Knee, K.L., E. Garcia-Solsona, J. Garcia-Orellana, A.B. Boehm, and A. Paytan. 2011. Using radium isotopes to characterize water ages and coastal mixing rates: a sensitivity analysis. Limnology and Oceanography-Methods 9: 380–395.CrossRefGoogle Scholar
  35. Knee, K.L., Crook, E.D., Hench, J.L., Leichter, J.J. and Paytan, A., 2016. Assessment of submarine groundwater discharge (SGD) as a source of dissolved radium and nutrients to Moorea (French Polynesia) coastal waters. Estuaries and Coasts, pp.1–18.Google Scholar
  36. Kroeger, K.D., P.W. Swarzenski, W.J. Greenwood, and C. Reich. 2007. Submarine groundwater discharge to Tampa Bay: nutrient fluxes and biogeochemistry of the coastal aquifer. Marine Chemistry 104 (1): 85–97.CrossRefGoogle Scholar
  37. Kwon, E.Y., G. Kim, F. Primeau, W.S. Moore, H.M. Cho, T. DeVries, J.L. Sarmiento, M.A. Charette, and Y.K. Cho. 2014. Global estimate of submarine groundwater discharge based on an observationally constrained radium isotope model. Geophysical Research Letters 41 (23): 8438–8444.CrossRefGoogle Scholar
  38. Liu, Q., et al. 2012. How significant is submarine groundwater discharge and its associated dissolved inorganic carbon in a river-dominated shelf system? Biogeosciences 9 (5): 1777–1795.CrossRefGoogle Scholar
  39. Liu, Q., et al. 2014. Effect of submarine groundwater discharge on the coastal ocean inorganic carbon cycle. Limnology and Oceanography 59 (5): 1529–1554.CrossRefGoogle Scholar
  40. Lorite-Herrera, M., K. Hiscock, and R. Jiménez-Espinosa. 2009. Distribution of dissolved inorganic and organic nitrogen in river water and groundwater in an agriculturally-dominated catchment, south-east Spain. Water, Air, and Soil Pollution 198 (1–4): 335–346.CrossRefGoogle Scholar
  41. Luek, J.L., and A.J. Beck. 2014. Radium budget of the York River estuary (VA, USA) dominated by submarine groundwater discharge with a seasonally variable groundwater end-member. Marine Chemistry 165 (0): 55–65.CrossRefGoogle Scholar
  42. Luo, X., and J.J. Jiao. 2016. Submarine groundwater discharge and nutrient loadings in Tolo Harbor, Hong Kong using multiple geotracer-based models, and their implications of red tide outbreaks. Water research 102: 11–31.Google Scholar
  43. Michael, H.A., M.A. Charette, and C.F. Harvey. 2011. Patterns and variability of groundwater flow and radium activity at the coast: a case study from Waquoit Bay, Massachusetts. Marine Chemistry 127 (1–4): 100–114.CrossRefGoogle Scholar
  44. Monsen, N.E., J.E. Cloern, L.V. Lucas, and S.G. Monismith. 2002. A comment on the use of flushing time, residence time, and age as transport time scales. Limnology and Oceanography 47 (5): 1545–1553.CrossRefGoogle Scholar
  45. Moore, W.S. 1996. Large groundwater inputs to coastal environments revealed by 226Ra enrichments. Nature 380: 612–614.CrossRefGoogle Scholar
  46. Moore, W.S. 1999. The subterranean estuary: a reaction zone of ground water and sea water. Marine Chemistry 65 (1): 111–125.Google Scholar
  47. Moore, W.S. 2000a. Ages of continental shelf waters determined from 223Ra and 224Ra. Journal of Geophysical Research 105 (C9): 117–122.Google Scholar
  48. Moore, W.S. 2000b. Determining coastal mixing rates using radium isotopes. Continental Shelf Research 20 (15): 1993–2007.Google Scholar
  49. Moore, W.S. 2007. Seasonal distribution and flux of radium isotopes on the southeastern US continental shelf. Journal of Geophysical Research: Oceans 112 (C10).Google Scholar
  50. Moore, W.S. 2010a. The effect of submarine groundwater discharge on the ocean. Annual Review of Marine Science 2: 59–88.CrossRefGoogle Scholar
  51. Moore, W.S. 2010b. A reevaluation of submarine groundwater discharge along the southeastern coast of North America. Global Biogeochemical Cycles 24 (4): GB4005.CrossRefGoogle Scholar
  52. Moore, W.S., and R. Arnold. 1996. Measurement of 223Ra and 224Ra in coastal waters using a delayed coincidence counter. Journal of Geophysical Research 101 (C1): 1321–1329.CrossRefGoogle Scholar
  53. Moore, W.S., and D.F. Reid. 1973. Extraction of radium from natural waters using manganese-impregnated acrylic fibers. Journal of Geophysical Research 78: 8880–8886.CrossRefGoogle Scholar
  54. Moore, W.S., and A.M. Wilson. 2005. Advective flow through the upper continental shelf driven by storms, buoyancy, and submarine groundwater discharge. Earth and Planetary Science Letters 235 (3–4): 564–576.CrossRefGoogle Scholar
  55. Moore, W.S., J.O. Blanton, and S.B. Joye. 2006. Estimates of flushing times, submarine groundwater discharge, and nutrient fluxes to Okatee Estuary, South Carolina. Journal of Geophysical Research 111: C09006. doi:10.1029/2005JC003041.CrossRefGoogle Scholar
  56. Moore, W.S., M. Beck, T. Riedel, M.R. Van Der Loeff, O. Dellwig, T.J. Shaw, B. Schnetger, and H.J. Brumsack. 2011. Radium-based pore water fluxes of silica, alkalinity, manganese, DOC, and uranium: A decade of studies in the German Wadden Sea. Geochimica et Cosmochimica Acta 75 (21): 6535–6555.Google Scholar
  57. Moosdorf, N., T. Stieglitz, H. Waska, H.H. Dürr, and J. Hartmann. 2015. Submarine groundwater discharge from tropical islands: a review. Grundwasser 20 (1): 53–67.CrossRefGoogle Scholar
  58. Park, S. 2004. Aspects of mangrove distribution and abundance in Tauranga Harbour. Report prepared by Stephen Park for Environment Bay of Plenty (Environmental Publication 2004/16).Google Scholar
  59. Park, S.G., 2011. Sea lettuce and nutrient monitoring in Tauranga Harbour 1991–2010. Bay of Plenty Regional Council.Google Scholar
  60. Peterson, R.N., et al. 2008a. Radon and radium isotope assessment of submarine groundwater discharge in the Yellow River Delta, China. Journal of Geophysical Research 113: C09021. doi:10.1029/2008JC004776.CrossRefGoogle Scholar
  61. Peterson, R.N., W.C. Burnett, N. Dimova, and I.R. Santos. 2009a. Comparison of measurement methods for radium-226 on manganese-fiber. Limnology and Oceanography: Methods 7: 196–205.CrossRefGoogle Scholar
  62. Peterson, R.N., W.C. Burnett, C.R. Glenn, and A.G. Johnson. 2009b. Quantification of point-source groundwater discharges to the ocean from the shoreline of the Big Island, Hawaii. Limnology and Oceanography 54 (3): 890–904.CrossRefGoogle Scholar
  63. Povinec, P.P., W.C. Burnett, A. Beck, H. Bokuniewicz, M. Charette, M.E. Gonneea, M. Groening, T. Ishitobi, E. Kontar, L.L.W. Kwong, and D.E.P. Marie. 2012. Isotopic, geophysical and biogeochemical investigation of submarine groundwater discharge: IAEA-UNESCO intercomparison exercise at Mauritius Island. Journal of Environmental Radioactivity 104: 24–45.CrossRefGoogle Scholar
  64. Rapaglia, J., C. Ferrarin, L. Zaggia, W.S. Moore, G. Umgiesser, E. Garcia-Solsona, J. Garcia-Orellana, and P. Masqué. 2010. Investigation of residence time and groundwater flux in Venice lagoon: comparing radium isotope and hydrodynamical models. Journal of Environmental Radioactivity 101 (7): 571–581.CrossRefGoogle Scholar
  65. Rodellas, V., J. Garcia-Orellana, P. Masqué, M. Feldman, and Y. Weinstein. 2015. Submarine groundwater discharge as a major source of nutrients to the Mediterranean Sea. Proceedings of the National Academy of Sciences 112 (13): 3926–3930.CrossRefGoogle Scholar
  66. Rodellas, V., J. Garcia-Orellana, G. Trezzi, P. Masqué, T.C. Stieglitz, H. Bokuniewicz, J.K. Cochran, and E. Berdalet. 2017. Using the radium quartet to quantify submarine groundwater discharge and porewater exchange. Geochimica et Cosmochimica Acta 196: 58–73.CrossRefGoogle Scholar
  67. Rosen, M.R. and White, P.A., 2001. Hydrochemistry of New Zealand’s aquifers. Groundwaters of New Zealand, pp. 77–110.Google Scholar
  68. Sadat-Noori, M., I.R. Santos, D.R. Tait, A. McMahon, S. Kadel, and D.T. Maher. 2016a. Intermittently closed and Open Lakes and/or lagoons (ICOLLs) as groundwater-dominated coastal systems: evidence from seasonal radon observations. Journal of Hydrology 535: 612–624.CrossRefGoogle Scholar
  69. Sadat-Noori, M., I.R. Santos, D.R. Tait, and D.T. Maher. 2016b. Fresh meteoric versus recirculated saline groundwater nutrient inputs into a subtropical estuary. Science of the Total Environment 566: 1440–1453.CrossRefGoogle Scholar
  70. Sanford, L.P., W.C. Boicourt, and S.R. Rives. 1992. Model for estimating tidal flushing of small embayments. Journal of Waterway, Port, Coastal, and Ocean Engineering 118 (6): 635–654.CrossRefGoogle Scholar
  71. Santos, I.R., and B.D. Eyre. 2011. Radon tracing of groundwater discharge into an Australian estuary surrounded by coastal acid sulphate soils. Journal of Hydrology 396 (3): 246–257.CrossRefGoogle Scholar
  72. Santos, I.R., W.C. Burnett, J. Chanton, B. Mwashote, I.G.N.A. Suryaputra, and T. Dittmar. 2008. Nutrient biogeochemistry in a Gulf of Mexico subterranean estuary and groundwater-derived fluxes to the coastal ocean. Limnology and Oceanography 53 (2): 705.CrossRefGoogle Scholar
  73. Santos, I.R., D. Erler, D. Tait, and B.D. Eyre. 2010. Breathing of a coral cay: tracing tidally driven seawater recirculation in permeable coral reef sediments. Journal of Geophysical Research 115: C12010.CrossRefGoogle Scholar
  74. Santos, I.R., P.L. Cook, L. Rogers, J.D. Weys, and B.D. Eyre. 2012. The “salt wedge pump”: convection-driven pore-water exchange as a source of dissolved organic and inorganic carbon and nitrogen to an estuary. Limnology and Oceanography 57 (5): 1415–1426.CrossRefGoogle Scholar
  75. Santos, I.R., J. de Weys, D.R. Tait, and B.D. Eyre. 2013. The contribution of groundwater discharge to nutrient exports from a coastal catchment: post-flood seepage increases estuarine N/P ratios. Estuaries and Coasts 36 (1): 56–73.CrossRefGoogle Scholar
  76. Santos, I.R., K.R. Bryan, C.A. Pilditch, and D.R. Tait. 2014. Influence of porewater exchange on nutrient dynamics in two New Zealand estuarine intertidal flats. Marine Chemistry 167 (0): 57–70.CrossRefGoogle Scholar
  77. Slomp, C.P., and P. Van Cappellen. 2004. Nutrient inputs to the coastal ocean through submarine groundwater discharge: controls and potential impact. Journal of Hydrology 295 (1–4): 64–86.CrossRefGoogle Scholar
  78. Smith, C.G., and P.W. Swarzenski. 2012. An investigation of submarine groundwater—borne nutrient fluxes to the west Florida shelf and recurrent harmful algal blooms. Limnology and Oceanography 57 (2): 471–485.CrossRefGoogle Scholar
  79. Smith, S.V., D.P. Swaney, L. Talaue-Mcmanus, J.D. Bartley, P.T. Sandhei, C.J. McLaughlin, V.C. Dupra, C.J. Crossland, R.W. Buddemeier, B.A. Maxwell, and F. Wulff. 2003. Humans, hydrology, and the distribution of inorganic nutrient loading to the ocean. AIBS Bulletin 53 (3): 235–245.Google Scholar
  80. Spiers, K.C., T.R. Healy, and C. Winter. 2009. Ebb-jet dynamics and transient eddy formation at Tauranga harbour: implications for entrance channel shoaling. Journal of Coastal Research 25(1): 234–247.CrossRefGoogle Scholar
  81. Spiteri, C., C.P. Slomp, K. Tuncay, and C. Meile. 2008. Modeling biogeochemical processes in subterranean estuaries: Effect of flow dynamics and redox conditions on submarine groundwater discharge of nutrients. Water Resources Research 44 (2). doi:10.1029/2007WR006071.
  82. Stewart, B.T., I.R. Santos, D.R. Tait, P.A. Macklin, and D.T. Maher. 2015. Submarine groundwater discharge and associated fluxes of alkalinity and dissolved carbon into Moreton Bay (Australia) estimated via radium isotopes. Marine Chemistry 174: 112.CrossRefGoogle Scholar
  83. Stokes, D.J., T.R. Healy, and P.J. Cooke. 2010. Expansion dynamics of monospecific, temperate mangroves and sedimentation in two embayments of a barrier-enclosed lagoon, Tauranga Harbour, New Zealand. Journal of Coastal Research 26 (1): 113–122.CrossRefGoogle Scholar
  84. Street, J.H., K.L. Knee, E.E. Grossman, and A. Paytan. 2008. Submarine groundwater discharge and nutrient addition to the coastal zone and coral reefs of leeward Hawai’i. Marine Chemistry 109 (3): 355–376.CrossRefGoogle Scholar
  85. Su, N., W.C. Burnett, H.L. MacIntyre, J.D. Liefer, R.N. Peterson, and R. Viso. 2014. Natural radon and radium isotopes for assessing groundwater discharge into Little Lagoon, AL: implications for harmful algal blooms. Estuaries and Coasts 37 (4): 893–910.CrossRefGoogle Scholar
  86. Swarzenski, P.W. 2007. U/Th series radionuclides as coastal groundwater tracers. Chemical Reviews 107 (2): 663–674.CrossRefGoogle Scholar
  87. Swarzenski, P.W., C. Reich, K.D. Kroeger, and M. Baskaran. 2007. Ra and Rn isotopes as natural tracers of submarine groundwater discharge in Tampa Bay, Florida. Marine Chemistry 104 (1): 69–84.CrossRefGoogle Scholar
  88. Tait, D.R., I.R. Santos, D.V. Erler, K.M. Befus, M.B. Cardenas, and B.D. Eyre. 2013. Estimating submarine groundwater discharge in a South Pacific coral reef lagoon using different radioisotope and geophysical approaches. Marine Chemistry 156: 49–60.CrossRefGoogle Scholar
  89. Tait, D.R., D.V. Erler, I.R. Santos, T.J. Cyronak, U. Morgenstern, and B.D Eyre. 2014. The influence of groundwater inputs and age on nutrient dynamics in a coral reef lagoon. Marine Chemistry 166: 36–47.Google Scholar
  90. Tay, H.W., K.R. Bryan, C.A. Pilditch, S. Park, and D.P. Hamilton. 2012. Variations in nutrient concentrations at different time scales in two shallow tidally dominated estuaries. Marine and Freshwater Research 63 (2): 95–109.CrossRefGoogle Scholar
  91. Tay, H.W., K.R. Bryan, W.P. de Lange, and C.A. Pilditch. 2013. The hydrodynamics of the southern basin of Tauranga Harbour. New Zealand Journal of Marine and Freshwater Research 47 (2): 249–274.CrossRefGoogle Scholar
  92. Thrush, S.F., J.E. Hewitt, V.J. Cummings, J.I. Ellis, C. Hatton, A.M. Lohrer, and A. Norkko. 2004. Muddy waters: elevating sediment input to coastal and estuarine habitats. Frontiers in Ecology and the Environment 2: 299–306.CrossRefGoogle Scholar
  93. Tomasky-Holmes, G., I. Valiela, and M.A. Charette. 2013. Determination of water mass ages using radium isotopes as tracers: implications for phytoplankton dynamics in estuaries. Marine Chemistry 156: 18–26.CrossRefGoogle Scholar
  94. Waska, H., and G. Kim. 2011. Submarine groundwater discharge (SGD) as a main nutrient source for benthic and water-column primary production in a large intertidal environment of the Yellow Sea. Journal of Sea Research 65 (1): 103–113.CrossRefGoogle Scholar
  95. Waska, H., S. Kim, G. Kim, R.N. Peterson, and W.C. Burnett. 2008. An efficient and simple method for measuring 226Ra using the scintillation cell in a delayed coincidence counting system (RaDeCC). Journal of Environmental Radioactivity 99 (12): 1859–1862.CrossRefGoogle Scholar
  96. White, P.A., 2005. Future use of groundwater resources in the Bay of Plenty region. Institute of Geological & Nuclear Sciences, Wairakei Research Centre.Google Scholar
  97. White, P.A., C. Meilhac, G. Zemansky, and G. Kilgour. 2008. Groundwater resource investigations of the Western Bay of Plenty area stage 1—conceptual geological and hydrological models and preliminary allocation assessment. GNS Science Consultancy Report 240: 221.Google Scholar

Copyright information

© Coastal and Estuarine Research Federation 2017

Authors and Affiliations

  • Benjamin T. Stewart
    • 1
  • Karin R. Bryan
    • 1
  • Conrad A. Pilditch
    • 1
  • Isaac R. Santos
    • 2
  1. 1.School of ScienceUniversity of WaikatoHamiltonNew Zealand
  2. 2.National Marine Science Centre, School of Environment, Science and EngineeringSouthern Cross UniversityCoffs HarbourAustralia

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