Skip to main content

An in situ mesocosm method for quantifying nitrogen cycling rates in oligotrophic wetlands using 15N tracer techniques

Abstract

Short term nitrogen uptake dynamics in the marshes of the southern Everglades, USA, were determined through implementation of a field mesocosm and isotopic enrichment method. The approach was tested using six mesocosms, three enriched with a 300‰ 15N tracer, Ca(NO3)2 (± 98% 15N) and three unenriched mesocosms. This 15N tracer technique allowed the determination of nitrogen fluxes between key ecosystem components. The in situ mesocosm experiment was conducted in a freshwater marl prairie marsh habitat for a period of 21 days. Macrophytes (Cladium jamaicense), periphyton, soil, and consumers (Gambusia holbrooki) were sampled at prescribed intervals to determine the optimal sampling periods necessary to capture peak 15N tracer uptake. Over the course of the study period, 15N tracer was detected in all ecosystem components sampled except for soils. Periphyton exhibited the most rapid initial 15N tracer uptake, with an increase of 3.86‰ to 7.79‰ (± 1.70) only 5 minutes after tracer addition. Periphyton 15N signatures continued to increase to 16.49‰ (± 6.45) and 108.15‰ (± 49.40) after 10 minutes and 6 hours, respectively. Increased 15N signatures were also noted in the macrophyte and consumer components, with peak tracer uptake values occurring in aboveground macrophyte tissue at t = 9 day (26.62‰ (± 5.00)), the belowground macrophyte tissue at t = 15 day (22.01‰ (± 5.83)), and in consumers at t = 15 day (297.09‰ (± 127.36)). Tracer uptake by the soil component was minimal with no significant amount of tracer being detected in any of the three soil layers sampled (0–1, 1–5, and 5–10 cm). This testing of the in situ mesocosm and 15N isotopic enrichment approach provides a foundation for further experimentation with the method at this and other wetland study sites.

This is a preview of subscription content, access via your institution.

Literature Cited

  • Adey, W. H., M. Finn, P. Kangas, L. Lange, C. Luckett, and D. M. Spoon. 1996. A Florida Everglades mesocosm — model veracity after four years of self-organization. Ecological Engineering 6: 171–224.

    Article  Google Scholar 

  • Ahn, C. and M. J. Mitsch. 2002. Scaling considerations of mesocosm wetlands in simulating large created freshwater marshes. Ecological Engineering 18: 327–42.

    Article  Google Scholar 

  • Banse, K. 1982. Experimental marine ecosystems enclosures in a historical perspective. p. 11–24. In G. D. Grice and M. R. Reeve (eds.) Marine Mesocosms. Springer-Verlag, New York, NY, USA.

    Google Scholar 

  • Carpenter, S. R. 1996. Microcosm experiments have limited relevance for community and ecosystem ecology. Ecology 77: 677–80.

    Article  Google Scholar 

  • Chambers, R. M. 1992. A fluctuating water-level chamber for biogeochemical experiments in tidal marshes. Estuaries 15: 53–58.

    Article  CAS  Google Scholar 

  • Connolly, R. M., M. A. Guest, A. J. Melville, and J. M. Oakes. 2004. Sulfur stable isotopes separate producers in marine foodweb analysis. Oecologia 138: 161–67.

    Article  PubMed  Google Scholar 

  • Craft, C. B. and C. J. Richardson. 1993. Peat accumulation and N, P and organic accumulation in nutrient-enriched and unenriched Everglades peatlands. Ecological Applications 3: 446–58.

    Article  Google Scholar 

  • Drenner, R. W. and A. Mazumder. 1999. Microcosm experiments have limited relevance for community and ecosystem ecology: comment. Ecology 80: 1081–85.

    Article  Google Scholar 

  • Duever, M. J., J. F. Meeder, L. C. Meeder, and J. M. McCollom. 1994. The climate of south Florida and its role in shaping the Everglades ecosystem. p. 225–48. In S. M. Davis and J. C. Ogden (eds.) Everglades: The Ecosystem and Its Restoration. St. Lucie Press, Delray Beach, FL, USA.

    Google Scholar 

  • Finn, M. 1996. The mangrove mesocosm of Biosphere 2: design, establishment and preliminary findings. Ecological Engineering 6: 21–56.

    Article  Google Scholar 

  • Gaiser, E. E., A. Zafiris, P. L. Ruiz, F. A. C. Tobias, and M. S. Ross. 2006. Tracking rates of ecotone migration due to saltwater encroachment using fossil mollusks in coastal South Florida. Hydrobiologia 569: 237–57.

    Article  Google Scholar 

  • Geddes, P. and J. C. Trexler. 2003. Uncoupling of omnivoremediated positive and negative effects on periphyton mats. Community Ecology 136: 585–95.

    Google Scholar 

  • Gehart, D. Z. and G. E. Likens. 1975. Enrichment experiments for determining nutrient limitation: four methods compared. Limnology and Oceanography 20: 649–53.

    Google Scholar 

  • Gleason, P. J. and W. Spackman. 1974. Calcareous periphyton and water chemistry in the Everglades. In P. J. Gleason (ed.) Environments of South Florida: Present and Past. University of Miami Press, Miami, FL, USA.

    Google Scholar 

  • Grice, G. D. and M. R. Reeve (eds.). Marine Mesocosms, Biological and Chemical Research in Experimental Ecosystems. Springer-Verlag, New York, NY, USA.

  • Gry, M. B., P. M. Gilbert, and C. C. Chen. 1999. Dimension effects of enclosures on ecological processes in pelagic systems. Limnology and Oceanography 44: 1331–40.

    Article  Google Scholar 

  • Hendry, M. J., L. I. Wassenaar, and T. K. Birkham. 2002. Microbial respiration and diffusive transport of O2, 16O2, and 18O16O in unsaturated soils: a mesocosm experiment. Geochimica et Cosmochimica Acta 66: 3367–74.

    Article  CAS  Google Scholar 

  • Holmes, R. M., B. J. Peterson, L. A. Deegan, J. E. Hughes, and B. Fry. 2000. Nitrogen biogeochemistry in the oligohaline zone of a New England estuary. Ecology 81: 416–32.

    Google Scholar 

  • Howarth, R. W., T. Butler, K. L. Lunde, D. Swaney, and C. R. Chu. 1993. Turbulence and planktonic nitrogen fixation: a mesocosm study. Limnology and Oceanography 38: 1696–1711.

    Article  Google Scholar 

  • Hughes, J. E., L. A. Deegan, B. J. Peterson, R. M. Holmes, and B. Fry. 2000. Nitrogen flow through the food web in the oligohaline zone of a New England estuary. Ecology 81: 433–52.

    Article  Google Scholar 

  • Iwaniec, D. M., D. L. Childers, D. Rondeau, C. J. Madden, and C. Saunders. 2006. Effects of hydrologic and water quality drivers on periphyton dynamics in the southern Everglades. Hydrobiologia 569: 223–35.

    Article  CAS  Google Scholar 

  • Kadlec, R. H., C. C. Tanner, V. M. Hally, and M. M. Gibbs. 2005. Nitrogen spiraling in subsurface-flow constructed wetlands: implications fro treatment response. Ecological Engineering 25: 365–81.

    Article  Google Scholar 

  • Kemp, W. M., W. R. Boynton, J. J. Cunningham, and J. C. Stevenson. 1980. Microcosms, macrophytes, and hierarchies: environmental research in the Chesapeake Bay. p. 911–36. In J. P. Giesy (ed.) Microcosms in Ecological Research. (DOE Symposium Series 52). US Department of Energy, Washington DC, USA.

    Google Scholar 

  • Kim, J. G. and E. Rejmankova. 2002. Recent history of sediment deposition in marl- and sand-based marshes of Belize, Central America. Catena 48: 267–91.

    Article  CAS  Google Scholar 

  • Light, S. S. and J. W. Dineen. 1994. Water control in the Everglades: a historical perspective. p. 47–84. In S. M. Davis and J. C. Ogden (eds.) Everglades: The Ecosystem and Its Restoration. St. Lucie Press, Delray Beach, FL, USA.

    Google Scholar 

  • MacNally, R. 1997. Scaling artifacts in confinement experiment: a simulation model. Ecological Modeling 99: 229–45.

    Article  Google Scholar 

  • Noe, G. B., D. L. Childers, and R. D. Jones. 2001. Phosphorus biogeochemistry and the impact of phosphorus enrichments: why is the Everglades so unique? Ecosystems 4: 603–24.

    Article  CAS  Google Scholar 

  • Noe, G. B., L. J. Scinto, J. Taylor, D. L. Childers, and R. D. Jones. 2003. Phosphorus cycling and partitioning in an oligotrophic Everglades wetland ecosystem: a radioisotope tracing study. Freshwater Biology 48: 1993–2008.

    Article  CAS  Google Scholar 

  • Odum, E. P. 1984. The mesocosm. BioScience 34: 558–62.

    Article  Google Scholar 

  • Parent, S. and A. Morin. 2000. N budget as water quality management tool in closed aquatic mesocosms. Water Research 34: 1846–56.

    Article  CAS  Google Scholar 

  • Parker, F. M., III. 2000. Quantifying spatial and temporal variability in marsh-water column interactions in a southern Everglades marsh. M.S. Thesis. Florida International University, Miami, FL, USA.

    Google Scholar 

  • Rejmankova, E. and J. Komarkova. 2000. A function of cyanobacterial mats in phosphorus-limited tropical wetlands. Hydrobiologia 431: 135–53.

    Article  CAS  Google Scholar 

  • Ross, M. S., J. F. Meeder, J. P. Sah, P. L. Ruiz, and G. J. Telesnicki. 2000. The Southeast Saline Everglades revisited: 50 years of coastal vegetation change. Journal of Vegetation Science 11: 101–12.

    Article  Google Scholar 

  • Rudnick, D. T., Z. Chen, D. L. Childers, J. N. Boyer, and T. D. Fontaine, III. 1999. Phosphorus and nitrogen inputs to Florida Bay: the importance of the Everglades watershed. Estuaries 22: 398–416.

    Article  CAS  Google Scholar 

  • Schaffranek, R. W. 1996. Coupling models for canal and wetland interactions in the south Florida ecosystem. U.S. Geological Survey. Fact Sheet FS-139096:4.

  • Schindler, D. W. 1998. Replication versus realism: the need for ecosystem-scale experiments. Ecosystems 1: 323–34.

    Article  Google Scholar 

  • Stephenson, G. L., P. Hamilton, N. K. Kaushik, J. B. Robinson, and K. R. Solomon. 1984. Spatial distribution of plankton in enclosures of three sizes. Canadian Journal of Fisheries and Aquatic Science 41: 1048–54.

    Article  Google Scholar 

  • Sutula, M. A., B. C. Perez, E. Reyes, D. L. Childers, S. Davis, J. W. Day, Jr., D. Rudnick, and F. Sklar. 2003. Factors affecting spatial and temporal variability in material exchange between the Southern Everglades wetlands and Florida Bay (USA). Estuarine, Coastal and Shelf Science 57: 757–81.

    Article  CAS  Google Scholar 

  • Svendsen, C. and J. M. Weeks. 1997. A simple low-cost field mesocosm for ecotoxicological studies on earthworms. Comparative Biochemical Physiology 117: 31–40.

    Google Scholar 

  • Trexler, J. C., W. F. Loftus, F. Jordan, J. H. Chick, K. L. Kandl, T. C. McElroy, and O. L. Bass, Jr. 2002. Ecological Scale and Its Implications for Freshwater Fishes in the Florida Everglades. p. 154–81. In J. W. Porter and K. G. Porter (eds.) The Everglades, Florida Bay, and Coral Reefs of the Florida Keys: An Ecosystem Sourcebook. CRC Press, Boca Raton, FL, USA.

    Google Scholar 

  • Vanni, M. J., C. D. Layne, and S. E. Arnott. 1997. “Top down” trophic interactions in lakes: effects of fish on nutrient dynamics. Ecology 78: 1–20.

    Google Scholar 

  • Zavarzin, G. A., V. K. Orleanskii, L. M. Gerasimenko, S. N. Pushko, and G. T. Ushtinskaya. 2003. Laboratory simulations of cyanobacterial mats of the alkaline geochemical barrier. Microbiology 72: 80–85.

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Wozniak, J.R., Childers, D.L., Anderson, W.T. et al. An in situ mesocosm method for quantifying nitrogen cycling rates in oligotrophic wetlands using 15N tracer techniques. Wetlands 28, 502–512 (2008). https://doi.org/10.1672/07-29.1

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1672/07-29.1

Key Words

  • Cladium jamaicense
  • Everglades
  • freshwater flow
  • hydrology
  • marl
  • nitrogen cycle
  • periphyton
  • restoration