Abstract
A diel biogeochemical study was performed to assess the influence that periods of elevated biological activity have on the biogeochemical cycling of macronutrients and redox-sensitive elements in a natural estuarine environment. High-resolution data (15 min sampling) illustrates periodic extreme variations in dissolved oxygen (DO) in the shallow waters of Azevedo Pond, Elkhom Slough, California. During periods of low tidal flushing, DO values can range from highly oxic (>560 μM O2: >250% saturation) during sunny days to suboxic conditions (<5 μM) at night. Nutrient cycling and redox-sensitive trace element biogeochemistry were evaluated in response to the extreme daily DO fluctuations. A diel sampling study was conducted over a 26-h period, where O2 concentrations ranged from 346 μM to sustained non-detectable levels in the night hours. In concert with the DO fluctuations, diel phosphate cycling was on the order of 4 μM in response to tidal flushing events and biological assimilation and regeneration. The IO3 −/I− redox couple quickly responded to suboxic conditions in the water column by a marked increase in I− concentrations and corresponding depletion of IO3 −. The extreme fluctuations of the p∈ in the water column resulted in diel dissolved Mn2+ variations of nearly 5 μM, with observed dissolved Mn removal rates on the order of 1 μM h−1. The elevated biogeochemical cycling of oxygen, nitrogen, phosphorus, iodine, manganese, and iron found in this shallow estuarine environment suggest that tidal restrictions and anthropogenic nutrient enrichments can amplify diel variations and potentially hinder the functional and ecological stability of these systems. These data suggest that accurate chemical monitoring of the health of an estuarine ecosystem must account for the diel variability inherent in these highly productive environments.
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Literature Cited
Ansfield, H. C. and G. Benott. 1997. Impacts of flow restrictions on salt marshes: An instance of acidification. Environmental Science and Technology 31:1650–1657.
Attwood, D. K., A. Bratkovich, M. Gallager, and G. L. Hitchoock (eds.). 1994. Papers from NOAA's Nutrient Enhanced Coastal Ocean Productivity Study. Esturies 17:729–903.
Bender, M. L. 1971. Does upward diffusion supply the excess manganese in pelagic sediments? Journal of Geophysical Research 76:4214–4215.
Bruland, K. W., R. P. Franks, G. A. Knauer, and J. H. Martin. 1979. Sampling and analytical methods for the determination of copper, cadmium and nickel in seawater. Analytica Chimica Acta 105:233–245.
Cline, J. D., and F. A. Richards. 1972. Oxygen deficient conditions and nitrate reduction in the eastern tropical North Pacific. Limnology and Oceanography 17:885–900.
Cloern, J. E. 1996. Phytoplankton bloom dynamics in coastal ecosystems: A review with some general lessons from sustained investigation of San Francisco Bay, California. Reviews of Geophysics 34:127–168.
Cooper, S. R. 1995. Chesapeake Bay watershed historical land use: Impact on water quality and diatom communities. Ecological Applications 5:703–723.
D'Avanzo, C. and J. N. Kremer. 1994. Diel oxyge dynamics and anoxic events in an eutrophic estuary of Waquoit Bay, Massachusetts. Estuaries 17:131–139.
Emerson, S., R. E. Cranston, and P. S. Liss. 1979. Redox species in a reducing fjord: equilibrium and kinetic considerations. Deep Sea Research 26:859–873.
Epping, E. H. G., V. Schoemann, and H. de Heij. 1998. Manganese and iron oxidation during benthic oxygenic photosynthesis. Estuarine, Coastal and Shelf Science 47:753–767.
Evans, G. T. and J. S. Parslow. 1985. A model of annual plankton cycles. Biological Oceanography 3:327–347.
Fiaderiro, M. and J. D. H. Strickland. 1968. Nitrate reduction and the occurrence of a deep nitrite maximum in the ocean off the west coast of South America. Journal of Marine Research 26:187–207.
Froelich, P. N., G. P. Klinkhammer, M. L. Bender, N. A. Luedtke, G. R. Heath, D. Cullen, P. Dauphin, D. Hammond, B. Hartman, and V. Maynard. 1979. Early oxidation of organic matter in pelagic sediments of the eastern equatorial Atlantic: Suboxic diagenesis. Geochimica et Cosmochimica Acta 43:1075–1090.
Hinga, K. R. 1992. Co-occurrence of dinoflagellate blooms and high pH in marine enclosures. Marine Ecological Progress Series 86:181–187.
Houghton, R. A. and D. L. Skole. 1990. Carbon, p. 393–308. In B. L. Turner, W. C. Clark, R. W. Kates, J. F. Richards, J. T. Mathew, and W. B. Meyer (eds.). The Earth as Transformed by Human Action. Cambridge University Press, Cambridge, Massachusetts.
Hunt, C. D. and J. R. Kelly. 1988. Manganese cycling in coastal regions: Response to eutrophication. Estuarine, Coastal and Shelf Science 26:527–558.
Johnson, K. S., W. M. Berelson, J. E. Coale, T. L. Coley, V. A. Elrod, W. R. Fairly, H. D. Iams, T. A. Kilgore, and J. L. Nowicki. 1992. Manganese flux from continental margin sediments in a transect through the oxygen minimum. Science 257:1242–1245.
Landing, W. M. and K. W. Bruland. 1987. The contrasting biogeochemistry of iron and manganese in the Pacific Ocean. Geochimica et Cosmochinica Acta 51:29–43.
Lewis, B. L. and W. M. Landing. 1991. The biogeochemistry of managanese of iron in the Black Sea. Deep-Sea Research 38:S773-S804.
Liss, P. S., F. R. Herring, and E. D. Goldberg. 1973. The iodide/iodate system in seawater as a possible measure of redox potential. Nature Physical Science 242:108–109.
Lucia, M. and A. M. Campos. 1997. New approach to evaluating dissolved iodine speciation in natural waters using cathodic stripping voltammetry and a storage study for preserving iodine species. Marine Chemistry 57:107–117.
Martin, J. H. and F. A. Knauer. 1984. VERTEX: Manganese transport through oxygen minima. Earth and Planetary Science Letters 67:35–47.
Nixon, S. W. 1995. Coastal marine eutrophication: A definition, social causes, and future concerns. Ophelia 41:199–219.
Officer, C. B., R. B. Biggs, J. L. Taft, L. E. Cronin, M. A. Tyler, and W. R. Boynton. 1984. Chesapeake Bay anoxia: Origin, development, and significance. Science 223:22–27.
Portnoy, J. W. 1991. Summer oxygen depletion in a diked New England Estuary. Estuaries 14:122–129.
Richards, F. A. and W. W. Broenkow. 1971. Chemical changes, including nitrate reduction, in Darwin Bay, Galapagos Archipelago, over a 2-month period. Limnology and Oceanography 16: 758–765.
Rue, E. L., G. J. Smith, G. A. Cutter, and K. W. Bruland. 1997. The response of trace element redox couples to suboxic conditions in the water column. Deep-Sea Research Part I Oceanographic Research Papers 44:113–134.
Smith, R. E. 1973. The hydrography of Elkhorn Slough a shallow California coastal embayment. Technical Publication 73-2, Annual Report, Part 2. Moss Landing Marine Laboratories, California.
Stumm, W. and J. J. Morgan. 1996. Aquatic Chemistry: Chemical Equilibria and Rates in Nature Waters, 3rd edition, John Wiley & Sons, New York.
Sunda, W. G. and S. A. Huntsman. 1987. Microbial oxidation of manganese in a North Carolina estuary. Limnology and Oceanography 32:552–564.
Sunda, W. G. and S. A. Huntsman. 1990. Diel cycles in microbial manganese oxidation and manganese redox speciation coastal waters of the Bahama Islands. Limnology and Oceanography 35:325–338.
Taft, J. L., E. O. Hartwig, and R. Loftus. 1980. Seasonal oxygen depletion in Chesapeake Bay. Estuaries 3:242–247.
Tebo, B. M. 1991. Manganese (II) oxidation in the suboxic zone of the black Sea. Deep-Sea Research 38:S883-S905.
Welsh, B. L. and F. C. Eller. 1991. Mechanisms controlling summertime oxygen depletion in western Long Island Sound. Estuaries 14:265–278.
Wetzel, R. G. 1975. Limnology. W.B. Saunders Company, Philadelphia, Pennsylvania.
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Beck, N.G., Bruland, K.W. Diel biogeochemical cycling in a hyperventilating shallow estuarine environment. Estuaries 23, 177–187 (2000). https://doi.org/10.2307/1352825
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DOI: https://doi.org/10.2307/1352825