Abstract
Although denitrification has the potential to reduce nitrate (NO −3 ) pollution of surface waters, the quantification of denitrification rates is complex because it requires differentiation from other mechanisms and is highly variable in both space and time. This study first measured potential denitrification rates at a wetland forest site in south Louisiana before receipt of secondary wastewater effluent, and then, following 30 months of effluent application, landscape gradients of dissolved nitrate (NO −3 ) and nitrous oxide (N2O) were measured. A computer model was developed to quantify N transformations. Floodwater NO −3 and N2O concentrations were higher in the forest receiving effluent than in the adjacent control forest. Denitrification rates of NO −3 -amended soil cores ranged from 0.03–0.45 g N m−2 d−1 with an overall mean of 0.10 g N m−2 d−1. Effluent N is being applied at a rate of approximately 0.034 g N m−2 d−1, with approximately 95% disappearing along a 1 km transect. In the treatment forest, floodwater NO −3 concentrations decreased from 1000 μM at the inflow point to 50 μM along the 1 km transect. Nitrous oxide concentrations increased from 0.25 μM to 1.2 μM within the first 100 m, but decreased to 0.1 μM over the next 900 m. The initial increase in N2O was presumably a result ofin situ denitrification. Model analyses indicated that denitrification was directly associated with nitrification and was limited by the availability of NO −3 produced by nitrification. Due to different redox potential optima, coupling of nitrification and denitrification was a function of a balance of environmental conditions that was moderately favorable to both processes. N removal efficiency was largely dependent on the proportion of effluent NH +4 to NO −3 . When NH +4 /NO −3 was ≤1, average N removal efficiency ranged from 95–100%, but ratios that were >1 reduced average efficiencies to as low as 57%. Actual effluent NH +4 /NO −3 loading ratios at this site are approximately 0.2 and are consistently <1.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Explore related subjects
Discover the latest articles, news and stories from top researchers in related subjects.References
Ambus, P. and Christensen, S. 1995. Spatial and seasonal nitrous oxide and methane fluxes in Danish forest-, grassland-, and agroecosystems. J. Environ. Qual. 24: 993–1001.
Anthony, W.H., Hutchinson, G.L. and Livingston, G.P. 1995. Chamber measurement of soil-atmosphere gas exchange: linear vs. diffusion-based flux models. Soil Sci. Soc. Am. J. 59: 1308–1310.
Conner, W.H. and Day, J. W. 1989. A use attainability analysis of forested wetlands for receiving treated municipal wastewater. Report to the city of Thibodaux, Louisiana.
Davidson, E.A. and Firestone, M.K. 1988. Measurement of nitrous oxide dissolved in soil solution. Soil Sci. Soc. Am. J. 52: 1201–1203.
Davidson, E.A. and Swank, W.T. 1990. Nitrous oxide dissolved in soil solution: an insignificant pathway of nitrogen loss from a southeastern hardwood forest. Water Resour. Res. 26: 1687–1690.
Dieberg, F.E. and Brezonik, P.L. 1984. Nitrogen and phosphorus mass balances in a cypress dome receiving wastewater.In: Ewel, K.C. and Odum, H.T. (eds). Cypress Swamps. pp. 112–118. University Presses of Florida, Gainsville, FL.
Engler, R.M. and Patrick, Jr. W.H. 1974. Nitrate removal from floodwater overlying flooded soils and sediments. J Environ. Qual. 3: 409–413.
Flessa, H. and Fischer, W.R. 1992. Plant-induced changes in the redox potentials of rice rhizospheres. Plant and Soil 143: 55–60.
Focht, D.D. and Verstraete, W. 1977. Biochemical ecology of nitrification and denitrification.In: Alexander, M. (ed.), Advances in Microbial Ecology. Volume 1. pp. 135–214. Plenum Press, New York.
Groffman, P.M. 1994. Denitrification in freshwater wetlands. Current Topics in Wetland Biogeochemistry 1: 15–35.
Groffman, P.M., Axelrod, E.A., Lemunyon, J.L. and Sullivan, W.M. 1991. Denitrification in grass and forest vegetated filter strips. J. Environ. Qual. 20: 671–674.
Healy, R.W., Striegl, R.G., Russell, T.F., Hutchinson, G.L. and Livingston, G.P. 1996. Numerical evaluation of staticchamber measurements of soil-atmosphere gas exchange: identification of physical processes. Soil Sci. Soc. Am. J. 60: 740–747.
Kemp, G.P. and Day, Jr. J.W. 1984. Nutrient dynamics in a Louisiana swamp receiving agricultural runoff.In: Ewel, K.C. and Odum, H.T. (eds). Cypress Swamps. pp. 286–293. University Presses of Florida, Gainesville, FL.
Lamontagne, M.G. and Valiela I. 1995. Denitrification measured by a direct N2 flux method in sediments of Waquoit Bay, MA. Biogeochemistry 31: 63–83.
McKenney, D.J., Drury, C.F. and Wang, S.W. 1996. Effect of acetylene on nitric oxide production in soil under denitrifying conditions. Soil Sci. Soc. Am. J. 60: 811–820.
Minami, K. and Ohsawa, A. 1990. Emission of nitrous oxide dissolved in drainage water from agricultural land.In: Bouwman, A.F. (ed.). Soils and the Greenhouse Effect. pp. 503–509, John Wiley and Sons Ltd., Chichester, England.
Mosier, A.R. and Mack, L. 1980. Gas chromatographic system for precise, rapid analysis of nitrous oxide. Soil Sci. Soc. Am. J. 44: 1121–1123.
Nichols, D.S. 1983. Capacity of natural wetlands to remove nutrients from wastewater. J. Water Pollut. Control Fed. 55: 495–505.
Nishio, T., Koike, I., and Hattori, A. 1981. N2/Ar and denitrification in Tama estuary sediments. Geomicrobiol. J. 2: 193–209.
Nowicki, B.L. 1994. The effect of temperature, oxygen, salinity, and rutrient enrichment on estuarine denitrification rates measured with a modified nitrogen gas flux technique. Estuar., Coastal Shelf Sci. 38: 137–156.
Parkin, T.B. 1987. Soil microsites as a source of denitrification variability. Soil Sci. Soc. Am. J. 51: 1194–1199.
Payne, W.J. 1973. Reduction of nitrogenous oxides by microorganisms. Bacteriol. Rev. 37: 409.
Reddy, K.R., Patrick, Jr. W.H. and Lindau, C.W. 1989. Nitrification-denitrification at the plant root-sediment interface in wetlands. Limnol. Oceanogr. 34: 1004–1013.
Rybczyk, J.M., Zhang, X.W., Day, Jr. J.W., Hesse, I. and Feagley, S. 1995. The impact of Hurricane Andrew on tree mortality, litterfall, nutrient flux, and water quality in a Louisiana coastal swamp forest. J. Coastal Res. 21: 340–353.
Strickland, J.D.H. and Parsons, T.R. 1972. A practical handbook of seawater analysis. Bulletin 167 (2nd edn). Fisheries Research Board of Canada. Ottawa, Canada.
Tiedje, J.M. 1982. Denitrification.In: Page, A.L. (ed.), Methods of Soil Analysis, Part 2. Chemical and Microbiological Properties—Agronomy Monograph no. 9 (2nd edn). pp. 1011–1026. American Society of Agronomy, Madison, WI.
Twilley, R.R. and Kemp, W.M. 1986. The relation of denitrification potentials to selected physical and chemical factors in sediments of Chesapeake Bay.In: Wolfe, D.A. (ed.), Estuarine Variability. pp. 277–293. Academic Press. Inc., Orlando, FL.
U.S. Environmental Protection Agency. 1979. Methods for chemical analysis of water and wastes. USEPA-600/4-79-020, Cincinnati, OH.
van Kessel, C., Pennock, D.J. and Farrell, R.E. 1993. Seasonal variations in denitrification and nitrous oxide evolution at the landscape scale. Soil Sci. Soc. Am. J. 57: 988–995.
Weier, K.L., Doran, J.W., Power, J.F. and Walters, D.T. 1993. Denitrification and the dinitrogen/nitrous oxide ratio as affected by soil water, available carbon, and nitrate. Soil Sci. Soc. Am. J. 57: 66–72.
Zhang, X. 1995. Use of a natural swamp for wastewater treatment. Ph.D. Dissertation. Louisiana State University, Baton Rouge, LA.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Boustany, R.G., Crozier, C.R., Rybczyk, J.M. et al. Denitrification in a South Louisiana wetland forest receiving treated sewage effluent. Wetlands Ecol Manage 4, 273–283 (1996). https://doi.org/10.1007/BF02150540
Issue Date:
DOI: https://doi.org/10.1007/BF02150540