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Estuaries and Coasts

, Volume 41, Issue 3, pp 734–750 | Cite as

Freshwater-Saltwater Mixing Effects on Dissolved Carbon and CO2 Outgassing of a Coastal River Entering the Northern Gulf of Mexico

  • Songjie He
  • Y. Jun XuEmail author
Article

Abstract

The delivery of dissolved carbon from rivers to coastal oceans is an important component of the global carbon budget. From November 2013 to December 2014, we investigated freshwater-saltwater mixing effects on dissolved carbon concentrations and CO2 outgassing at six locations along an 88-km-long estuarine river entering the Northern Gulf of Mexico with salinity increasing from 0.02 at site 1 to 29.50 at site 6 near the river’s mouth. We found that throughout the sampling period, all six sites exhibited CO2 supersaturation with respect to the atmospheric CO2 pressure during most of the sampling trips. The average CO2 outgassing fluxes at site 1 through site 6 were 162, 177, 165, 218, 126, and 15 mol m−2 year−1, respectively, with a mean of 140 mol m−2 year−1 for the entire river reach. In the short freshwater river reach before a saltwater barrier, 0.079 × 108 kg carbon was emitted to the atmosphere during the study year. In the freshwater-saltwater mixing zone with wide channels and river lakes, however, a much larger amount of carbon (3.04 × 108 kg) was emitted to the atmosphere during the same period. For the entire study period, the river’s freshwater discharged 0.25 × 109 mol dissolved inorganic carbon (DIC) and 1.77 × 109 mol dissolved organic carbon (DOC) into the mixing zone. DIC concentration increased six times from freshwater (0.24 mM) to saltwater (1.64 mM), while DOC showed an opposing trend, but to a lesser degree (from 1.13 to 0.56 mM). These findings suggest strong effects of freshwater-saltwater mixing on dissolved carbon dynamics, which should be taken into account in carbon processing and budgeting in the world’s estuarine systems.

Keywords

Dissolved inorganic carbon Dissolved organic carbon CO2 outgassing Calcasieu River Gulf of Mexico 

Notes

Acknowledgements

This study was financially supported through grants from the National Fish and Wildlife Foundation (Project # 8004.12.036402) and the US Department of Agriculture Hatch Funds (Project # LAB94230). The data used are listed in the tables, figures, and supporting information of the paper. Thanks go to the US Geological Survey for making the river discharge and gage height data available for this study and to Syam K. Dodla and Manoch Kongchum for laboratory carbon analysis at the Central Analytical Instruments Research Laboratory, Louisiana State University Agricultural Center. Thanks also go to Yuyan Zhou and Bo Wang for drainage area and water surface area calculations and to Daniel Cohen for proofreading the manuscript. The authors are grateful to many students including, among others, Kaci Fisher, Paula Castello Blindt, Sanjeev Joshi, and Zhen Xu for their outstanding field assistance. Finally, the authors thank the editor and anonymous reviewers for their careful readings of the manuscript and constructive suggestions.

Conflict of Interest

The authors declare that they have no conflict of interest.

Supplementary material

12237_2017_320_MOESM1_ESM.docx (1.2 mb)
ESM 1 (DOCX 1215 kb)

References

  1. Abril, G., J.-M. Martinez, L.F. Artigas, P. Moreira-Turcq, M.F. Benedetti, L. Vidal, et al. 2014. Amazon River carbon dioxide outgassing fueled by wetlands. Nature 505: 395–398.CrossRefGoogle Scholar
  2. Aitkenhead, J.A., and W.H. McDowell. 2000. Soil C:N ratio as a predictor of annual riverine DOC flux at local and global scales. Global Biogeochemical Cycles 14: 127–138.CrossRefGoogle Scholar
  3. Aitkenhead, J.A., D. Hope, and M.F. Billett. 1999. The relationship between dissolved organic carbon in stream water and soil organic carbon pools at different spatial scales. Hydrological Processes 13: 1289–1302.CrossRefGoogle Scholar
  4. Amiotte Suchet, P., J.L. Probst, and W. Ludwig. 2003. Worldwide distribution of continental rock lithology: implications for the atmospheric/soil CO2 uptake by continental weathering and alkalinity river transport to the oceans. Global Biogeochemical Cycles 17: 1038.CrossRefGoogle Scholar
  5. Amon, R.M.W., and R. Benner. 1996. Photochemical and microbial consumption of dissolved organic carbon and dissolved oxygen in the Amazon River system. Geochimica et Cosmochimica Acta 60: 1783–1792.CrossRefGoogle Scholar
  6. Aucour, A.M., S.M.F. Sheppard, O. Guyomar, and J. Wattelet. 1999. Use of 13C to trace origin and cycling of inorganic carbon in the Rhône river system. Chemical Geology 159: 87–105.CrossRefGoogle Scholar
  7. Aufdenkampe, A.K., E. Mayorga, P.A. Raymond, J.M. Melack, S.C. Doney, S.R. Alin, et al. 2011. Riverine coupling of biogeochemical cycles between land, oceans, and atmosphere. Frontiers in Ecology and the Environment 9: 53–60.CrossRefGoogle Scholar
  8. Benner, R., and S. Opsahl. 2001. Molecular indicators of the sources and transformations of dissolved organic matter in the Mississippi River plume. Organic Geochemistry 32: 597–611.CrossRefGoogle Scholar
  9. Bianchi, T.S., T. Filley, K. Dria, and P.G. Hatcher. 2004. Temporal variability in sources of dissolved organic carbon in the lower Mississippi River. Geochimica et Cosmochimica Acta 68: 959–967.CrossRefGoogle Scholar
  10. Bodin, S., P. Meissner, N.M.M. Janssen, T. Steuber, and J. Mutterlose. 2015. Large igneous provinces and organic carbon burial: controls on global temperature and continental weathering during the Early Cretaceous. Global and Planetary Change 133: 238–253.CrossRefGoogle Scholar
  11. Borges, A.V., and G. Abril. 2011. Carbon dioxide and methane dynamics in estuaries. In Treatise on Estuarine and Coastal Science - Volume 5: Biogeochemistry, ed. E. Wolanski and D.S. McLusky, 119–161. Waltham: Academic Press.CrossRefGoogle Scholar
  12. Borges, A.V., F. Darchambeau, C.R. Teodoru, T.R. Marwick, F. Tamooh, N. Geeraert, et al. 2015. Globally significant greenhouse gas emissions from African inland waters. Nature Geoscience 8: 637–642.CrossRefGoogle Scholar
  13. Brunet, F., D. Gaiero, J.L. Probst, P.J. Depetris, F. Gauthier Lafaye, and P. Stille. 2005. δ13C tracing of dissolved inorganic carbon sources in Patagonian rivers (Argentina). Hydrological Processes 19: 3321–3344.CrossRefGoogle Scholar
  14. Butman, D., and P.A. Raymond. 2011. Significant efflux of carbon dioxide from streams and rivers in the United States. Nature Geoscience 4: 839–942.CrossRefGoogle Scholar
  15. Cai, W.J. 2003. Riverine inorganic carbon flux and rate of biological uptake in the Mississippi River plume. Geophysical Research Letters 30: 1032.Google Scholar
  16. Cai, W.-J., and Y. Wang. 1998. The chemistry, fluxes, and sources of carbon dioxide in the estuarine waters of the Satilla and Altamaha rivers, Georgia. Limnology and Oceanography 43 (4): 657–668.CrossRefGoogle Scholar
  17. Cai, W.-J., L.R. Pomeroy, M.A. Moran, and Y. Wang. 1999. Oxygen and carbon dioxide mass balance for the estuarine–intertidal marsh complex of five rivers in the southeastern U.S. Limnology and Oceanography 44 (3): 639–649.CrossRefGoogle Scholar
  18. Cai, W.J., X.H. Guo, C.T.A. Chen, M.H. Dai, L.J. Zhang, W.D. Zhai, et al. 2008. A comparative overview of weathering intensity and HCO3 flux in the world’s largest rivers with emphasis on the Changjiang, Huanghe, Zhujiang (pearl) and Mississippi rivers. Continental Shelf Research 28: 1538–1549.CrossRefGoogle Scholar
  19. Cai, Y., M.J. Shim, L. Guo, and A. Shiller. 2016. Floodplain influence on carbon speciation and fluxes from the lower Pearl River, Mississippi. Geochimica et Cosmochimica Acta 186: 189–206.CrossRefGoogle Scholar
  20. Cauwet, G. 2002. DOM in the coastal zone. In Biogeochemistry of marine dissolved organic matter, ed. D.A. Hansell and C.A. Carlson, 579–609. Cambridge: Academic Press.CrossRefGoogle Scholar
  21. Cole, J.J., Y.T. Prairie, N.F. Caraco, W.H. McDowell, L.J. Tranvik, R.G. Striegl, et al. 2007. Plumbing the global carbon cycle: integrating inland waters into the terrestrial carbon budget. Ecosystems 10: 172–185.CrossRefGoogle Scholar
  22. Cory, R.M., C.P. Ward, B.C. Crump, and G.W. Kling. 2014. Sunlight controls water column processing of carbon in arctic fresh waters. Science 345: 925–928.CrossRefGoogle Scholar
  23. Dai, M., Z. Yin, F. Meng, Q. Liu, and W.J. Cai. 2012. Spatial distribution of riverine DOC inputs to the ocean: an updated global synthesis. Current Opinion in Environmental Sustainability 4: 170–178.CrossRefGoogle Scholar
  24. Dixon, T.H., F. Amelung, A. Ferretti, F. Novali, F. Rocca, R. Dokka, et al. 2006. Space geodesy: Subsidence and flooding in New Orleans. Nature 441: 587–588.CrossRefGoogle Scholar
  25. Doi, T., S. Osafune, N. Sugiura, S. Kouketsu, A. Murata, S. Masuda, et al. 2015. Multidecadal change in the dissolved inorganic carbon in a long-term ocean state estimation. Journal of Advances in Modeling Earth Systems 7: 1885–1900.CrossRefGoogle Scholar
  26. Dubois, K.D., D. Lee, and J. Veizer. 2010. Isotopic constraints on alkalinity, dissolved organic carbon, and atmospheric carbon dioxide fluxes in the Mississippi River. Journal of Geophysical Research: Biogeosciences 115: G02018.CrossRefGoogle Scholar
  27. Etcheber, H., A. Taillez, G. Abril, J. Garnier, P. Servais, F. Moatar, et al. 2007. Particulate organic carbon in the estuarine turbidity maxima of the Gironde, Loire and Seine estuaries: origin and lability. Hydrobiologia 588: 245–259.CrossRefGoogle Scholar
  28. Fichot, C.G., and R. Benner. 2014. The fate of terrigenous dissolved organic carbon in a river-influenced ocean margin. Global Biogeochemical Cycles 28: 300–318.CrossRefGoogle Scholar
  29. Forsgren, G., M. Jansson, and P. Nilsson. 1996. Aggregation and sedimentation of iron, phosphorus and organic carbon in experimental mixtures of freshwater and estuarine water. Estuarine, Coastal and Shelf Science 43: 259–268.CrossRefGoogle Scholar
  30. Fransner, F., J. Nycander, C.M. Mörth, C. Humborg, H.E.M. Meier, R. Hordoir, et al. 2016. Tracing terrestrial DOC in the Baltic Sea—a 3-D model study. Global Biogeochemical Cycles 30: 134–148.CrossRefGoogle Scholar
  31. Gao, J.H., Y.P. Wang, S.M. Pan, R. Zhang, J. Li, and F.L. Bai. 2008. Distribution of organic carbon in sediments and its influences on adjacent sea area in the turbidity maximum of Changjiang Estuary in China. Acta Oceanologica Sinica 27: 83–94.Google Scholar
  32. Goolsby, D.A., W.A. Battaglin, B.T. Aulenbach, and R.P. Hooper. 2001. Nitrogen input to the Gulf of Mexico. Journal of Environmental Quality 30: 329–336.CrossRefGoogle Scholar
  33. Guo, L., Y. Cai, C. Belzile, and R. Macdonald. 2012. Sources and export fluxes of inorganic and organic carbon and nutrient species from the seasonally ice-covered Yukon River. Biogeochemistry 107: 187–206.CrossRefGoogle Scholar
  34. Harrison, J.A., N. Caraco, and S.P. Seitzinger. 2005. Global patterns and sources of dissolved organic matter export to the coastal zone: results from a spatially explicit, global model. Global Biogeochemical Cycles 19: GB4S04.Google Scholar
  35. He, S., and Y.J. Xu. 2015. Three decadal inputs of total organic carbon from four major coastal river basins to the summer hypoxic zone of the Northern Gulf of Mexico. Marine Pollution Bulletin 90: 121–128.CrossRefGoogle Scholar
  36. He, S., and Y.J. Xu. 2016. Spatiotemporal distributions of Sr and Ba along an Estuarine River with a large salinity gradient to the Gulf of Mexico. Water 2016 (8): 323.CrossRefGoogle Scholar
  37. He, S., and Y.J. Xu. 2017. Assessing dissolved carbon transport and transformation along an estuarine river with stable isotope analyses. Estuarine, Coastal and Shelf Science.  https://doi.org/10.1016/j.ecss.2017.08.024.
  38. Hedges, J.I., and R.G. Keil. 1995. Sedimentary organic matter preservation: an assessment and speculative synthesis. Marine Chemistry 49: 81–115.CrossRefGoogle Scholar
  39. Hope, D., M.F. Billet, and M.S. Cresser. 1994. A review of the export of carbon in river water: fluxes and processes. Environmental Pollution 84: 301–324.CrossRefGoogle Scholar
  40. Hope, D., M.F. Billett, and M.S. Cresser. 1997. Exports of organic carbon in two river systems in NE Scotland. Journal of Hydrology 193: 61–82.CrossRefGoogle Scholar
  41. Hu, X., W.J. Cai, N.N. Rabalais, and J. Xue. 2016. Coupled oxygen and dissolved inorganic carbon dynamics in coastal ocean and its use as a potential indicator for detecting water column oil degradation. Deep Sea Research Part II: Topical Studies in Oceanography 129: 311–318.CrossRefGoogle Scholar
  42. Huang, W.J., W.J. Cai, Y. Wang, X. Hu, B. Chen, S.E. Lohrenz, et al. 2015. Hopkinson. The response of inorganic carbon distributions and dynamics to upwelling-favorable winds on the northern Gulf of Mexico during summer. Continental Shelf Research 111: 211–222.CrossRefGoogle Scholar
  43. Humborg, C., C.M. Mörth, M. Sundbom, H. Borg, H. Blenckner, R. Giesler, et al. 2009. CO2 supersaturation along the aquatic conduit in Swedish watersheds as constrained by terrestrial respiration, aquatic respiration and weathering. Global Change Biology 16: 1966–1978.CrossRefGoogle Scholar
  44. Ivins, E.R., R.K. Dokka, and R.G. Blom. 2007. Post-glacial sediment load and subsidence in coastal Louisiana. Geophysical Research Letters 34: L16303.CrossRefGoogle Scholar
  45. Johnson, M.S., J. Lehmann, S.J. Riha, A.V. Krusche, J.E. Richey, J.P.H.B. Ometto, et al. 2008. CO2 efflux from Amazonian headwater streams represents a significant fate for deep soil respiration. Geophysical Research Letters 35: L17401.CrossRefGoogle Scholar
  46. Kempe, S., M. Pettine, and G. Cauwet. 1991. Biogeochemistry of European rivers. In Biogeochemistry of Major World Rivers, SCOPE 42, ed. E.T. Degens, S. Kempe, and J.E. Richey, 169–212. Hoboken: John Wiley.Google Scholar
  47. Kim, Y., T.H. Kim, and T. Ergun. 2015. The instability of the Pearson correlation coefficient in the presence of coincidental outliers. Finance Research Letters 13: 243–257.CrossRefGoogle Scholar
  48. Lambert, T., S. Bouillon, F. Darchambeau, P. Massicotte, and A.V. Borges. 2016. Shift in the chemical composition of dissolved organic matter in the Congo River network. Biogeosciences 13: 5405–5420.CrossRefGoogle Scholar
  49. Lerman, A., L. Wu, and F.T. Mackenzie. 2007. CO2 and H2SO4 consumption in weathering and material transport to the ocean, and their role in the global carbon balance. Marine Chemistry 106: 326–350.CrossRefGoogle Scholar
  50. Li, G.J., J. Hartmann, L.A. Derry, A.J. West, C.F. You, X.Y. Long, et al. 2016. Temperature dependence of basalt weathering. Earth and Planetary Science Letters 443: 59–69.CrossRefGoogle Scholar
  51. Lucotte, M. 1989. Organic carbon isotope ratios and implications for the maximum turbidity zone of the St Lawrence upper estuary. Estuarine, Coastal and Shelf Science 29: 293–304.CrossRefGoogle Scholar
  52. Ludwig, W., J.L. Probst, and S. Kempe. 1996. Predicting the oceanic input of organic carbon by continental erosion. Global Biogeochemical Cycles 1996 (10): 23–41.CrossRefGoogle Scholar
  53. Mannino, A., and H.R. Harvey. 2001. Terrigenous dissolved organic matter along an estuarine gradient and its flux to the coastal ocean. Organic Geochemistry 31: 1611–1625.CrossRefGoogle Scholar
  54. Mantoura, R.F.C., and E.M.S. Woodward. 1983. Conservative behaviour of riverine dissolved organic carbon in the Severn Estuary: chemical and geochemical implications. Geochimica et Cosmochimica Acta 47: 1293–1309.CrossRefGoogle Scholar
  55. Meybeck, M. 1982. Carbon, nitrogen, and phosphorus transport by world rivers. American Journal of Science 282: 401–450.CrossRefGoogle Scholar
  56. Meybeck, M. 1993. Riverine transport of atmospheric carbon: sources, global typology and budget. Water, Air, & Soil Pollution 70: 443–463.CrossRefGoogle Scholar
  57. Moran, M.A., W.M. Sheldon Jr., and J.E. Sheldon. 1999. Biodegradation of riverine dissolved organic carbon in five estuaries of the southeastern United States. Estuaries 22: 55–64.CrossRefGoogle Scholar
  58. Mulholland, P.J. 1981. Formation of particulate organic carbon in water from a southeastern swamp-stream. Limnology and Oceanography 26: 790–795.CrossRefGoogle Scholar
  59. Mulholland, P.J., G.V. Wilson, and P.M. Jardine. 1990. Hydrogeochemical response of a forested watershed to storms: effects of preferential flow along shallow and deep pathways. Water Resources Research 26: 3021–3036.CrossRefGoogle Scholar
  60. Powell, R.T., W.M. Landing, and J.E. Bauer. 1996. Colloidal trace metals, organic carbon and nitrogen in a southeastern U.S. estuary. Marine Chemistry 55: 165–176.CrossRefGoogle Scholar
  61. Raymond, P.A., and J.J. Cole. 2001. Gas exchange in rivers and estuaries: choosing a gas transfer velocity. Estuaries 24: 312–317.CrossRefGoogle Scholar
  62. Raymond, P.A., N.H. Oh, R.E. Turner, and W. Broussard. 2008. Anthropogenically enhanced fluxes of water and carbon from the Mississippi River. Nature 451: 449–452.CrossRefGoogle Scholar
  63. Raymond, P.A., C.J. Zappa, D. Butman, T.L. Bott, J. Potter, P. Mulholland, A.E. Laursen, et al. 2012. Scaling the gas transfer velocity and hydraulic geometry in streams and small rivers. Limnology and Oceanography Fluids and Environments 2: 41–53.CrossRefGoogle Scholar
  64. Raymond, P.A., J. Hartmann, R. Lauerwald, S. Sobek, C. McDonald, M. Hoover, et al. 2013. Global carbon dioxide emissions from inland waters. Nature 503: 355–359.CrossRefGoogle Scholar
  65. Roberts, B.J., and S.M. Doty. 2015. Spatial and temporal patterns of benthic respiration and net nutrient fluxes in the Atchafalaya River Delta Estuary. Estuaries and Coasts 38: 1918–1936.CrossRefGoogle Scholar
  66. Schlesinger, W.H., and J.M. Melack. 1981. Transport of organic carbon in the world’s rivers. Tellus 33: 172–181.CrossRefGoogle Scholar
  67. Schurr, J.M., and J. Ruchti. 1977. Dynamics of O2 and CO2 exchange, photosynthesis, and respiration in rivers from time-delayed correlations with ideal sunlight. Limnology and Oceanography 22: 208–225.CrossRefGoogle Scholar
  68. Servais, P., and J. Garnier. 2006. Organic carbon and bacterial heterotrophic activity in the maximum turbidity zone of the Seine estuary (France). Aquatic Sciences 68: 78–85.CrossRefGoogle Scholar
  69. Shen, Y., C.G. Fichot, and R. Benner. 2012. Floodplain influence on dissolved organic matter composition and export from the Mississippi-Atchafalaya River system to the Gulf of Mexico. Limnology and Oceanography 57: 1149–1160.CrossRefGoogle Scholar
  70. Shilla, D.J., M. Tsuchiya, and D.A. Shilla. 2011. Terrigenous nutrient and organic matter in a subtropical river estuary, Okinawa, Japan: origin, distribution and pattern across the estuarine salinity gradient. Journal of Chemical Ecology 27: 523–542.CrossRefGoogle Scholar
  71. Søndergaard, M., C.A. Stedmon, and N.H. Borch. 2003. Fate of terrigenous dissolved organic matter (DOM) in estuaries: aggregation and bioavailability. Ophelia 57: 161–176.CrossRefGoogle Scholar
  72. Tian, H., W. Ren, J. Yang, B. Tao, W.J. Cai, S.E. Lohrenz, et al. 2015. Climate extremes dominating seasonal and interannual variations in carbon export from the Mississippi River basin. Global Biogeochemical Cycles 29: 1333–1347.CrossRefGoogle Scholar
  73. USACE (United States Army Corps of Engineers). 2010. Calcasieu River and Pass, Louisiana dredged material management plan and supplemental environmental impact statement. http://www.mvn.usace.army.mil/Portals/56/docs/PD/Projects/CalcasieuDMMP/DMMP_SEIS%20Main%20Report-November%2022%202010.pdf. Accessed 16 April 2017.
  74. USACE (United States Army Corps of Engineers). (n.d.). The Calcasieu Saltwater Barrier, http://www.mvn.usace.army.mil/Portals/56/docs/PAO/Brochures/CalcasieuSWB.pdf. Accessed 16 April 2017.
  75. USDA (United States Department of Agriculture) NRCS (National Resources Conservation Service). 1988. Soil survey of Calcasieu Parish, Louisiana. http://www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/louisiana/LA019/0/calcasieu.pdf. Accessed 16 April 2017.
  76. USDA (United States Department of Agriculture) NRCS (National Resources Conservation Service). 1995. Soil survey of Cameron Parish, Louisiana. http://www.nrcs.usda.gov/Internet/FSE_MANUSCRIPTS/louisiana/LA023/0/Cameron.pdf. Accessed 16 April 2017.
  77. van Geldern, R., P. Schulte, M. Mader, A. Baier, and J.A.C. Barth. 2015. Spatial and temporal variations of pCO2, dissolved inorganic carbon and stable isotopes along a temperate karstic watercourse. Hydrological Processes 29: 3423–3440.CrossRefGoogle Scholar
  78. Wehr, J.D., S.P. Lonergan, and J.H. Thorp. 1997. Concentrations and controls of dissolved organic matter in a constricted-channel region of the Ohio River. Biogeochemistry 38: 41–65.CrossRefGoogle Scholar
  79. Weiss, R.F. 1974. Carbon dioxide in water and seawater: the solubility of a non-ideal gas. Marine Chemistry 2: 203–215.CrossRefGoogle Scholar
  80. Wu, K., and Y.J. Xu. 2007. Long-term freshwater inflow and sediment discharge into Lake Pontchartrain in Louisiana, USA. Hydrological Sciences Journal 52 (1): 166–180.CrossRefGoogle Scholar
  81. Xu, Y.J. 2013. Transport and retention of nitrogen, phosphorus and carbon in north America’s largest river swamp basin, the Atchafalaya River Basin. Water 5: 379–393.CrossRefGoogle Scholar
  82. Xue, J., W.J. Cai, X. Hu, W.J. Huang, S.E. Lohrenz, and K. Gundersen. 2015. Temporal variation and stoichiometric ratios of organic matter remineralization in bottom waters of the northern Gulf of Mexico during late spring and summer. Journal of Geophysical Research, Oceans 120: 8304–8326.CrossRefGoogle Scholar
  83. Zhang, N., D. Kee, and P. Li. 2013. Investigation of the impacts of gulf sediments on Calcasieu Ship Channel and surrounding water systems. Computers & Fluids 77: 125–133.CrossRefGoogle Scholar

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© Coastal and Estuarine Research Federation 2017

Authors and Affiliations

  1. 1.School of Renewable Natural ResourcesLouisiana State University Agricultural CenterBaton RougeUSA

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