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Re-examining the Antarctic Paradox: speculation on the Southern Ocean as a nutrient-limited system

  • Julian Priddle (a1), David B. Nedwell (a2), Michael J. Whitehouse (a1), David S. Reay (a2), Graham Savidge (a3), Linda C. Gilpin (a3), Eugene J. Murphy (a1) and J. Cynan Ellis-Evans (a1)...

Abstract

The Southern Ocean is the largest of the high-nutrient, low-chlorophyll (HNLC) regions of the world ocean. Phytoplankton production fails to utilise completely the pool of inorganic nutrients in the euphotic zone, giving rise to low phytoplankton bio-mass and leaving relatively high summer nutrient concentrations. This enigma is of considerable significance for our understanding of the role of the oceans in the global carbon cycle. Various limiting factors have been considered: low light, low temperature, absence of necessary trace elements, grazing pressure and other means of biomass removal.

The dynamics of nitrogen uptake by phytoplankton are of particular importance. Classically, nitrate mixed into the surface layer during winter provides the nitrogen pool for growth in the spring bloom. Some organic material is exported to depth, whilst the remainder is recycled, providing ammonium and other reduced species as nitrogenous substrates for growth during the remainder of the season. The oxidation state of the inorganic nitrogen supply thus identifies new and recycled carbon fixation. Whilst this is convenient “shorthand” for the nitrogen nutrition of carbon export in much of the ocean, it is an inappropriate model for the Southern Ocean. Here, nitrate and ammonium use are simultaneous, and nitrate is never exhausted by the annual phytoplankton production.

We speculate that a range of environmental factors combine to make the large pool of nitrate partially inaccessible to phytoplankton. in addition to the documented effects of low iron availability and high ammonium concentrations, the low temperatures characteristic of the Southern Ocean may decrease nitrate availability because of the increased energetic overheads in its uptake and reduction. This in turn makes ammonium an important nitrogenous substrate, and its production by zooplankton and heterotrophic microorganisms is an important component of the plankton nitrogen cycle. There is some evidence that ammonium production by large grazing animals may stimulate phytoplankton growth. Microbial removal of nitrogen from sedimenting phytoplankton cells may result in local decoupling between the carbon and nitrogen cycles, allowing some reduced nitrogen to remain in the euphotic zone whilst carbon is exported to depth.

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References

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Banse, K. 1996. Low seasonality of low concentrations of surface chlorophyll in the subantarctic water ring: underwater irradiance, iron, or grazing? Prog. Oceanogr., 37, 241–291.
Capriulo, G. M., Sherr, E. B. and Sherr, B. P.. 1991. Trophic behaviour and related feeding activities of heterotrophic marine protists. In Reid, P. C., Turley, C. M. and Burkill, P. H.. eds. Protozoa and their role in marine processes. Berlin, Springer-Verlag, 219265.
Coale, K. H. and 18 others. 1996. A massive phytoplankton bloom induced by an ecosystem-scale iron fertilization experiment in the equatorial Pacific Ocean. Nature. 383(6600), 495501.
Copin-Montegut, C. and Copin-Montegut, G.. 1983. Stoichiometry of carbon, nitrogen and phosphorus in marine particulate matter. Deep-Sea Res., Ser. A, 30(1). 3146.
Davies, A. G. 1990. Taking a cool look at iron. Nature, 345(6271), 114–115.
De Barr, H. J. W. and 6 others. 1995. Importance of iron for phytoplankton blooms and carbon dioxide drawdown in the Southern Ocean. Nature, 373(6513), 412–415.
Dugdale, R. C. and Goering, J. J.. 1967. Uptake of new and regenerated forms of nitrogen in primary productivity. Limnol. Oceanogr, 12(2), 196–206.
El-Sayed, S. Z. 1984. Productivity of the Antarctic waters — a reappraisal. In Holm-Hansen, O., Bolis, L. and Gilles, R., eds. Mannephytoplankton and productivity. Berlin, Springer-Verlag, 1934.
Eppley, R. W. 1972. Temperature and phytoplankton growth in the sea. Fish, Bull. (NOAA), 70(4), 1062–1090.
Eppley, R. W. and Peterson, B. J.. 1979. Particulate organic matter flux and planktonic new production in the deep ocean. Nature, 282(5740), 677680.
Flynn, K. J. 1991. Algal carbon-nitrogen metabolism: a biochemical basis for modelling the interactions between nitrate anil ammonium uptake. J. Plankton Res., 13, 373–387.
Flynn, K. J., Fasham, M. J. R. and Hipkin, C. R.. 1997. Modelling the interactions between ammonium and nitrate uplake in marine phytoplankton. Philos. Trans. R. Soc, London, Ser. B, 352, 1–22.
Gilbert, P. M., Biggs, D. C. and McCarthy, J. J.. 1982. Utilization of ammonium and nitrate during austral summer in the Scotia Sea. Deep-Sea Res., Ser. . A, 29(7), 837850.
Hart, T. J. 1934. On the phytoplankton of the south-west Atlantic and the Bellingshausen Sea, 1929 31. Discovery Rep. 8.
Hein, M. and Sand-Jensen, K.. 1997. CO2 increases oceanic primary production. Nature 388(6642), 526–527.
Hoch, M. P. and Kirchman, D. L.. 1995. Ammonium uptake by heterotrophic bacteria in the Delaware estuary and adjacent coastal waters. Limnol. Oheanogr., 40(5), 886–897.
Jacques, G. 1983. Some ecophysiological aspects of the Antarctic phytoplankton. Polar Biol, 2(1), 27–33.
Jennings, J. C. Jr. Gordon, L. I. and Nelson, D. M.. 1984. Nutrient depletion indicates high primary productivity in the Weddell Sea. Nature, 309(5963), 5154.
I., Koike, Holm-Hansen, O. and Biggs, D. G.. 1986. Inorganic nitrogen metabolism by Antarctic phytoplankton with special reference to ammonium cycling. Mar. Ecol. Prog. Ser., 30, 105–116.
Loeb, V. and 6 others. 1997. Effects of sea-ice extent and krill or salp dominance on the Antarctic food web. Nature, 387(6636), 897–900.
Longhurst, A. R. 1991. Role of the marine biosphere in the global carbon cycle. Limnol. Oceanogr., 36(8), 15071526.
Longhurst, A., Sathyendranath, S., Plau, T. and Caverhill, G. 1995. Estimate of global primary production in the ocean from satellite radiometer data. J. Plankton Res., 17(6), 1245–1271.
Löscher, B. M., de Baar, H. J. W., de Jong, J. T. M., Veth, C. and Dchairs, F.. 1997. The distribution of Fe in the Antarctic Circumpolar Current Deep-Sea Res., Ser. II 44(1-2), 143–187.
Martin, J. H. 1990. Glacial interglacial CO2 change: the iron hypothesis. Paleoeeanography, 5(1), 1–13.
Mitchell, B. G. and Holm-Hansen, O.. 1991. Observations and modelling of the Antarctic phytoplankton crop in relation to mixing depth. Deep-Sea Res., Ser. A, 38(8-9), 9811007.
Peng, T. -H. and Broecker, W. S.. 1991. Dynamic limitations on the Antarctic iron fertilization strategy. Nature, 349(6306), 227–229.
Priddle, J., Hawes, L., Ellis-Evans, J. C. and Smith, T. J.. 1986. Antarctic aquatic ecosystems as habitats for phytoplankton. Biol. Rev. Cambridge Philos. Soc, 61(3), 199–238.
Priddle, J., Waikins, J. L., Morris, D. J., Ricketts, C. and Buchholz, F.. 1990. Variation of feeding by krill in swarms. J. Planklon Res., 12(6). 11891205.
Priddle, J., Smetacek, V. and Bathmann, U. V.. 1992. Antarctic marine primary production, biogeochemical carbon cycles and climate change. Philos. Trans. R. Soc. Undon, Ser. B, 338(1285), 289–297.
Priddle, J. and 7 others. 1995. Nutrient cycling by Antarctic marine microbial plankton. Mar Ecol Prog. Ser., 116, 181198.
Priddle, J., White-house, M. J., Atkinson, A., Brierley, A. S. and Murphy, E. J.. 1997. Diurnal changes in near-surface layer ammonium concentration interplay between zooplankton and phytoplankton. J. Plankton Res., 19(9), 13051330.
Priddle, J., Boyd, I. L., Whitehouse, M. J., Murphy, E. J. and Croxall, J. P.. in press. Estimates of Southern Ocean primary production — constraints from predator carbon demand and nutrient drawdown. J. Mar. Syst.
Raven, J. A. and Geider, R. J.. 1988. Temperature and algal growth. New Phytol, 110(4), 441–461.
Redfield, A. C., Ketchum, B. H. and Richards, F. A.. 1963. The influence of organisms on the composition of seawater. In Hill, M. N., ed. The sea. New York, Wiley Interscience, 2677.
Rice, A. L and 6 others. 1986. Seasonal deposition of phytodetritus to the deep-sea floor. Prot R. Soc. Edinburgh, Sect. B, 88, 265–279.
Riebesell, U., Wblf-Gladrow, D. A. and Smetacek, V.. 1993. Carbon dioxide limitation of marine phytoplankton growth rates. Nature, 361(6409), 249–251.
Rönner, U., Sorensson, F. and Holm-Hansen, O.. 1983. Nitrogen assimilation by phytoplankton in the Scotia Sea. Polar Biol, 2(3), 137–147.
Sambrotto, R. N. and 9 others. 1993. Elevated consumption of carbon relative to nitrogen in the surface ocean. Nature, 363(6426), 248–250.
Sarmiento, J- L. and Orr, J. C.. 1991, Three-dimensional simulations of the impact of Southern Ocean nutrient depletion on atmospheric CO, and ocean chemistry. Limnol. Oceanogr., 36(8), 1928–1950.
Sathyendranath, S., Gouveia, A. D., Shetye, S. R., Ravindran, P. and Platt, T.. 1991. Biological control of surface temperature in the Arabian Sea. Nature, 349(6304), 5456.
Scientific Committee on Oceanographic Research (SCOR). 1990. The Joint Global Ocean flux Study (JGOFS): science plan. Halifax, N. S., Scientific Committee on Oceanographic Research, (JGOFS Report 5.)
Smith, D. C., Simon, M., Alldredge, A. L. and Azam, F.. 1992. Intense hydrolytic enzyme activity on marine aggregates and implications for rapid particle dissolution. Nature, 359(6391), 139–142.
Smith, W. O. 1991. Nutrient distributions and new production in polar regions: parallels and contrasts between the Arctic and Antarctic. Mar. Chem., 35(1-4), 245257.
Smith, W. O. and Gordon, L. L.. 1997. Hyper productivity of the Ross Sea (Antarctica) polynya during austral spring. Geophys. Res. Lett, 24(3). 233236.
Tett, P. B. 1990. The photic zone. In Herring, P. J., Campbell, A. K., Whitfield, M. and Maddoek, L., eds. Light and life in the sea. Cambridge, Cambridge University Press. 5987.
Tilzer, M. M., Elbrächtcr, M., Gieskes, W. W. and Beese, B.. 1986. Light temperature interactions in the control of photosynthesis in Antarctic phytoplankton. Polar Biol., 5(2), 105111.
Turner, S. M., P. D., Nightingale, L. J., Spokes, Liddicoat, M. I. and Liss, P. S.. 1996. Increased dimethylsulphide concentrations in sea water from in situ iron enrichment. Nature, 383(6600), 513–517.
Wheeler, P. A. and Kokkinakis, S. A.. 1990. Ammonium recycling limits nitrate use in the oceanic subarctic Pacific. Limnol. Oceanogr., 35(6), 1267–1278.
Whitehouse, M. J., Priddle, J., Trat han, P. N. and Brandon, M. A.. 1996. Substantial open-ocean phytoplankton blooms to the north of South Georgia, South Atlantic, during summer 1994. Mar. Ecol. Prog. Ser. 140(1-3), 187197.
Williams, P. J. LeB. and Robertson, J. E.. 1991. Overall planktonic oxygen and carbon dioxide metabolisms: the problem of reconciling observations and calculations of photosynthetic quotients. J. Plankton Res., 13, Supplement, 153169.
Williams, P. J. LeB., Rainé, R. C. T. and Bryan, J. R.. 1979. Agreement between the l4G and oxygen methods of measuring phytoplankton production: reassessment of the photosynthetic quotient. Oceanol. Acta, 2(4), 411–416.
Zeebe, R. E., Eicken, H., Robinson, D. H., Wolf-Gladrow, D. and Dieckmann, G. S.. 1996. Modelling the heating and melting of sea ice through light absorption by microalgae. J. Geophys. Res., 101 (C1), 11631181.

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