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Transport of dissolved organic nitrogen in Mississippi River plume and Texas-Louisiana continental shelf near-surface waters

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Abstract

Dissolved organic nitrogen (DON) in near-surface (<20 m depth) waters of the Texas-Louisiana continental shelf is the predominant form of total dissolved nitrogen that is advected by the Mississippi-Atchafalaya River plume. Relatively high DON concentrations associated with low-salinity (<33 psu) waters throughout the year can be traced within the plume along the Texas-Louisiana inner shelf. DON concentrations throughout the shelf were significantly higher near the Mississippi-Atchafalaya outflow region relative to downstream inner Gulf shelf locations. Significant intercruise variations were also evident, with the highest concentrations during May 1992 and lower values in October 1992. At a fixed location off the Mississippi River outflow region DON concentration covaried inversely with salinity on time scales of hours to months, confirming that source water is a determining factor for variations of bulk DON concentrations in the region. Similar variations in upper water DON concentrations at different locations and seasons occurred in both plume and nonplume waters, which resembled the seasonal concentration changes of riverine nitrogen, and show that this pool is useful in tracing the influence of riverine-derived nitrogen on the overall nitrogen balance of the NW Gulf of Mexico’s continental shelf. Plume and nonplume DON concentrations deviated from mixing lines between riverine and oceanic endmembers, suggesting that plume waters may be a sink and nonplume waters may be a source of a labile fraction of DON in the region.

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Literature Cited

  • Abacus Concepts, Inc. 1987. StatView II. V. 1.0. Berkeley, California.

  • Benner, R., G. Chin-Leo, W. Gardner, B. Eadie, andJ. Contner. 1992. The fates and effects of riverine and shelf-derived DOM on Mississippi River plume/Gulf shelf processes, p. 84–94.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Biggs, D. C., M. A. Johnson, R. R. Bidigare, J. D. Guffy, and O. Holm-Hansen. 1982. Shipboard autoanalyzer studies of nutrient chemistry. Department of Oceanography, Texas A&M University, Tech. Rept. 82-11-T. Galveston, Texas.

  • Bratkovich, A. andS. P. Dinnel. 1992. Lower Mississippi River historical nitrate flux and Mississippi River outflow buoyancy flux, p. 37–42.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Bronk, D. A. andP. M. Glibert. 1991. A15N tracer method for the measurement of dissolved organic nitrogen release by phytoplankton.Marine Ecology Progress Series 77:171–182.

    Article  CAS  Google Scholar 

  • Cifuentes, L. A., R. A. Coffin, and D. López-Veneroni. 1993. Dissolved organic nitrogen cycling in the water column and sediments of the Mississippi River plume region. ASLO Summer Meeting, Edmonton, Canada (May 1993) (Abstract).

  • Cochrane, J. D. andF. J. Kelly. 1986. Low-frequency circulation on the Texas-Louisiana continental shelf.Journal of Geophysical Research 91:10,645–10,659.

    Article  Google Scholar 

  • Dagg, M. J. and P. B. Ortner. 1992. Mesozooplankton grazing and the fate of carbon in the northern Gulf of Mexico, p. 117–121.In NECOP Conference Proceedings. Texas Sea Grant Publications, TAMU-SG-92-109. Galveston, Texas.

  • Dagg, M. J. andT. E. Whitledge. 1992. Concentrations of copepod nauplii associated with the nutrient-rich plume of the Mississippi River.Continental Shelf Research 11:1409–1423.

    Article  Google Scholar 

  • Deltapoint, Inc. 1991. DeltaGraph Professional. V. 1.0.2. Monterey, California.

  • Dortch, Q., A. Bode, andR. R. Twilley. 1992. Nitrogen uptake and regeneration in surface waters of the Louisiana continental shelf influenced by the Mississippi River, p. 52–56.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Dortch, Q. andT. E. Whitledge. 1992. Does nitrogen or silicon limit phytoplankton production in the Mississippi River plume and nearby regions?Continental Shelf Research 12:1293–1309.

    Article  Google Scholar 

  • Fahnenstiel, G. L., M. Marcovitz, M. J. McCormick, D. G. Redalje, S. E. Lohrenz, H. J. Carrick, andM. J. Dagg. 1992. High growth and microzooplankton-grazing loss rates for phytoplankton populations from the Mississippi River plume region, p. 111–116.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Glibert, P. M., C. Garside, J. A. Furham, andM. R. Roman. 1991. Time-dependent coupling of inorganic and organic nitrogen uptake and regeneration in the plume of the Chesapeake Bay estuary and its regulation by large heterotrophs.Limnology and Oceanography 36:895–909.

    Google Scholar 

  • Harrison, W. G. 1978. Experimental measurements of nitrogen remineralization in coastal waters.Limnology and Oceanography 23:684–694.

    CAS  Google Scholar 

  • Hitghcock, G. andT. E. Whitledge. 1992. Nutrient/pigment variability in the Mississippi River plume and adjacent waters, p. 43–51.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Jackson, G. A. andP. M. Eldridge. 1992. Food web analysis of a planktonic system off Southern California.Progress in Oceanography 30:223–251.

    Article  Google Scholar 

  • Jackson, G. A. andP. M. Williams. 1985. Importance of disolved organic nitrogen and phosphorus to biological nutrient cycling.Deep-Sea Research 32:223–235.

    Article  CAS  Google Scholar 

  • Jumars, P. A., D. L. Penry, J. A. Baross, M. J. Perry, andB. W. Frost. 1989. Closing the microbial loop: Dissolved carbon pathway to heterotrophic bacteria from incomplete ingestion, digestion, and absorption in animals.Deep-Sea Research 36:483–495.

    Article  CAS  Google Scholar 

  • Kirchman, D. L., Y. Suzuki, C. Garside, andH. G. Ducklow. 1991. High turnover rates of dissolved organic carbon during a spring phytoplankton bloom.Nature 352:612–614.

    Article  CAS  Google Scholar 

  • LATEX Data Office. 1992. Field work begins on Gulf oceanography study.LATEX Fortnightly 1:1.

    Google Scholar 

  • Lohrenz, S. E., M. J. Dagg, andT. E. Whitledge. 1990. Enhanced primary production at the plume/oceanic interface of the Mississippi River.Continental Shelf Research 10:639–664.

    Article  Google Scholar 

  • Lohrenz, S. E., D. G. Redalje, G. L. Fahnenstiel, andG. A. Lang. 1992. Regulation and distribution of primary production in the northern Gulf of Mexico, p. 95–104.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • López-Veneroni, D. andL. A. Cifuentes. 1992. Dissolved organic nitrogen distribution and transport in the continental shelf of the northwest Gulf of Mexico, p. 57–68.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Rabalais, N. N., R. E. Turner, andW. J. Wiseman, Jr. 1992. Distribution and characteristics of hypoxia on the Louisiana shelf in 1990 and 1991, p. 15–20.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Rabalais, N. N., R. E. Turner, W. J. Wiseman, Jr., and D. F. Boesch. 1991. A brief summary of hypoxia on the northern Gulf of Mexico continental shelf: 1985–1988, p. 35–47.In R. V. Tyson and T. H. Pearson (eds.), Modern and Ancient Continental Shelf Anoxia. Geological Society of America Special Publication No. 58.

  • Redalje, D. G., S. E. Lohrenz, andG. L. Fahnenstiel. 1992. The relationship between primary production and the export of POM from the photic zone in the Mississippi River Plume and Inner Gulf of Mexico shelf regions, p. 105–110.In Nutrient Enhanced Coastal Ocean Productivity. Publication Number TAMU-SG-92-109, Sea Grant Program, Texas A&M University, Galveston, Texas.

    Google Scholar 

  • Sahl, L. E., W. J. Merrell, Jr., andD. C. Biggs. 1993. The influence of advection on the spatial variability of nutrient concentrations on the Texas-Louisiana continental shelf.Continental Shelf Research 13:233–251.

    Article  Google Scholar 

  • Sharp, J. H., C. H. Culberson, andT. M. Church. 1982. The chemistry of the Delaware Estuary. General considerations.Limnology and Oceanography 27:1015–1028.

    Article  CAS  Google Scholar 

  • Sklar, F. H. andR. E. Turner. 1981. Characteristics of phytoplankton production off Barataria Bay in an area influenced by the Mississippi River.Contributions in Marine Science 24:92–106.

    Google Scholar 

  • Suzuki, Y., E. Tanoue, andH. Ito. 1992. A high-temperature catalytic oxidation for the determination of dissolved organic carbon in seawater: Analysis and improvement.Deep-Sea Research 39:185–198.

    Article  CAS  Google Scholar 

  • Turner, R. E. andN. N. Rabalais. 1991. changes in Mississippi River water quality this century.BioScience 41:140–147.

    Article  Google Scholar 

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López-Veneroni, D., Cifuentes, L.A. Transport of dissolved organic nitrogen in Mississippi River plume and Texas-Louisiana continental shelf near-surface waters. Estuaries 17, 796–808 (1994). https://doi.org/10.2307/1352748

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