, Volume 17, Issue 1, pp 131–139 | Cite as

Diel oxygen dynamics and anoxic events in an eutrophic estuary of Waquoit Bay, Massachusetts

  • Charlene D’Avanzo
  • James N. Kremer


As a result of nutrient loading from septic systems, a thick canopy of macroalgae covers the bottom of Waquoit Bay, an embayment on Cape Cod, Massachusetts. Using automated conductivity-temperature-oxygen recorders and manual profiles, we measured diel water column O2 changes during summer in the Childs River, the estuary of the bay with the highest housing density. At dawn in midsummer, bottom waters in the Childs River are chronically hypoxic due to high rates of benthic respiration. On sunny days benthic photosynthesis drives bottom water O2 to 10–15 mg l−1 by afternoon. The extent of the daily O2 excursion is directly proportional to daily irradiance. Large diel O2 excursions in bottom water are due to limited mixing of surface and bottom water. Density stratification exceeded two sigma-t units 85% of the time during midsummer in the Childs River. Because of stratification, hypoxia and even anoxia occur in this estuary. The first of several anoxic events was observed in Waquoit Bay in 1988, and we have attempted to evaluate factors that trigger anoxia. High rates of benthic respiration result in anoxia when replenishment of O2 during the day is limited by insufficient light. Our analysis of meteorological records during two recent anoxic events shows that anoxia develops overnight in midsummer during periods of peak summertime temperatures after several days of cloudy, moderately calm weather. Similarly critical conditions existed most summers since 1975, yet anoxic events in the bay have not been reported historically. If climatic warming occurs, anoxic events in the bay may occur more frequently even if algal stocks remain unchanged. Eutrophication of Waquoit Bay is similar to many other embayments in populated coastal areas, and anoxic events may indicate a chronic growing problem in these important ecosystems. However, in shallow, stratified embayments, anoxia may be transient and easily missed without frequent monitoring.


Macroalgae Bottom Water Septic System Anoxic Event Oxygen Dynamics 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Literature cited

  1. Gordon, D. M., P. B. Birch, andA. J. McComb. 1980. The effect of light, temperature, and salinity on photosynthetic rates of an estuarineCladophora.Botanica Marina 23:749–755.Google Scholar
  2. Herreid, C. F. 1980. Hypoxia in invertebrates.Comparative Biochemistry and Physiology 67A:311–320.Google Scholar
  3. Lee, V. andS. Olsen. 1985. Eutrophication and management initiatives for the control of nutrient inputs to Rhode Island coastal lagoons.Estuaries 8:191–202.CrossRefGoogle Scholar
  4. Margalef, R. 1974. Ecologia. Ediciones Omega, S.A., Barcelona, Spain. 951 p.Google Scholar
  5. McComb, A. J., R. P. Atkins, P. B. Birch, D. M. Gordon, andR. J. Lukatelich. 1981. Eutrophication in the Peel-Harvey estuarine system, Western Australia, p. 324–432.In B. Nielson and E. Cronin (eds.), Estuaries and Nutrients. Humana Press, New Jersey.Google Scholar
  6. Nixon, S. W. andC. A. Oviatt. 1973. Ecology of a New England salt marsh.Ecological Monographs 43:463–498.CrossRefGoogle Scholar
  7. Nixon, S. W. 1982. Nutrient dynamics, primary production and fisheries yield of lagoons. Oceanological Acta Proceedings of the International Symposium on Coastal Lagoons. SCOR/IABO/UNESCO, Bordeaux, 8–14 September, 357–371.Google Scholar
  8. Officer, C. B., R. B. Biggs, J. L. Taft, L. E. Cronin, M. A. Tyler, andW. R. Boynton. 1984. Chesapeake Bay anoxia: Origin, development, and significance.Science 223:22–27.CrossRefGoogle Scholar
  9. Parker, C. A. andJ. E. O’Reilly. 1991. Oxygen depletion in Long Island Sound: A historical perspective.Estuaries 14:248–264.CrossRefGoogle Scholar
  10. Price, K. S., D. A. Flemer, J. L. Taft, G. B. Mackiernan, W. Nehlsen, R. B. Briggs, N. H. Burger, andD. A. Baylock. 1985. Nutrient enrichment of Chesapeake Bay and its impact on the habitat of striped bass: A speculative hypothesis.Transactions of the American Fisheries Society 114:97–106.CrossRefGoogle Scholar
  11. Rosenberg, R. 1985. Eutrophication—The future marine coastal nuisance?Marine Pollution Bulletin 16:227–231.CrossRefGoogle Scholar
  12. Saucerman, S. E. andL. A. Deegan. 1991. Lateral and cross-channel movement of young-of-the-year flounder in (Pseudopleuronectes americanus) in Waquoit Bay, Massachusetts.Estuaries 14:440–446.CrossRefGoogle Scholar
  13. Sfriso, A., A. Marcomini, andB. Pavoni. 1987. Relationship between macroalgal biomass and nutrient concentration in a hypertrophic area on the Venice lagoon.Marine Environmental Research 22:287–312.CrossRefGoogle Scholar
  14. Stanley, D. W. andS. W. Nixon. 1992. Stratification and bottom-water hypoxia in the Pamlico River estuary.Estuaries 3: 270–281.CrossRefGoogle Scholar
  15. Turner, R. E., W. W. Schroeder, andW. J. Wiseman, Jr. 1987. The role of stratification in the deoxygenation of Mobile Bay and adjacent shelf bottom waters.Estuaries 10:13–19.CrossRefGoogle Scholar
  16. Valiela, I. andJ. Costa. 1988. Eutrophication of Buttermilk Bay, a Cape Cod coastal embayment: Concentration of nutrients and watershed nutrient budgets.Environmental Management 12:539–551.CrossRefGoogle Scholar
  17. Valiela, I., K. Foremann, M. LaMontagne, D. Hersh, J. Costa, P. Peckol, B. DeMeo-Anderson, C. D’Avanzo, M. Babione, C. Sham, J. Brawley, andK. Lajtha. 1992. Couplings of watersheds and coastal waters: Sources and consequences of nutrient enrichment in Waquoit Bay.Estuaries 15:443–457.CrossRefGoogle Scholar
  18. Webb, K. L. andC. F. D’Elia. 1980. Nutrient and oxygen redistribution during a spring neap tidal cycle in a temperate estuary.Science 207:983–985.CrossRefGoogle Scholar
  19. Welsh, B. L. andF. C. Eller. 1991. Mechanisms controlling summertime oxygen depletion in western Long Island Sound.Estuaries 14:265–278.CrossRefGoogle Scholar

Copyright information

© Estuarine Research Federation 1994

Authors and Affiliations

  • Charlene D’Avanzo
    • 1
  • James N. Kremer
    • 2
  1. 1.School of Natural SciencesHampshire CollegeAmherst
  2. 2.Department of BiologyUniversity of Southern CaliforniaLos Angeles

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