Hydrobiologia

, Volume 569, Issue 1, pp 437–447 | Cite as

Nutrient impacts on epifaunal density and species composition in a subtropical seagrass bed

  • Melissa Gil
  • Anna R. Armitage
  • James W. Fourqurean
Article

Abstract

The capacity of epifauna to control algal proliferation following nutrient input depends on responses of both grazers and upper trophic level consumers to enrichment. We examined the responses of Thalassia testudinum (turtle grass) epifaunal assemblages to nutrient enrichment at two sites in Florida Bay with varying levels of phosphorus limitation. We compared epifaunal density, biomass, and species diversity in 2 m2 plots that had either ambient nutrient concentrations or had been enriched with nitrogen and phosphorus for 6 months. At the severely P-limited site, total epifaunal density and biomass were two times higher in enriched than in unenriched plots. Caridean shrimp, grazing isopods, and gammarid amphipods accounted for much of the increase in density; brachyuran crabs, primary predatory fish, and detritivorous sea cucumbers accounted for most of the increase in biomass. At the less P-limited site, total epifaunal density and biomass were not affected by nutrient addition, although there were more caridean shrimp and higher brachyuran crab and pink shrimp biomass in enriched plots. At both sites, some variation in epifaunal density and biomass was explained by features of the macrophyte canopy, such as T. testudinum and Halodule wrightii percent cover, suggesting that enrichment may change the refuge value of the macrophyte canopy for epifauna. Additional variation in epifaunal density and biomass was explained by epiphyte pigment concentrations, suggesting that enrichment may change the microalgal food resources that support grazing epifauna. Increased epifaunal density in enriched plots suggests that grazers may be able to control epiphytic algal proliferation following moderate nutrient input to Florida Bay.

Keywords

Direct and indirect epiphytes Halodule wrightii structure Thalassia testudinum trophic 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Supplementary material

supp.pdf (12 kb)

References

  1. Armitage, A. R., Fong, P. 2004Upward cascading effects of nutrients: shifts in a benthic microalgal community and a negative herbivore responseOecologia139560567PubMedCrossRefGoogle Scholar
  2. Armitage, A. R., Frankovich, T. A., Fourqurean, J. W. 2006Variable responses within epiphytic and benthic microalgal communities to nutrient enrichmentHydrobiologia569423435Google Scholar
  3. Armitage, A. R., Frankovich, T. A., Heck, K. L.,Jr., Fourqurean, J. W. 2005Experimental nutrient enrichment causes complex changes in seagrass, microalgae, and macroalgae community structure in Florida BayEstuaries28422434Google Scholar
  4. Bologna, P. A. X., Heck, K. L. 1999Macrofaunal associations with seagrass epiphytes: relative importance of trophic and structural characteristicsJournal of Experimental Marine Biology and Ecology2422139CrossRefGoogle Scholar
  5. Bustamante, R. H., Branch, G. M., Eekhout, S., Robertson, B., Zoutendyk, P., Schleyer, M., Dye, A., Hanekom, N., Keats, D., Jurd, M., McQuaid, C. 1995Gradients of intertidal primary productivity around the coast of South Africa and their relationships with consumer biomassOecologia102189201CrossRefGoogle Scholar
  6. Cardoso, P. G., Pardal, M. A., Lillebø, A. I., Ferreira, S. M., Raffaelli, D., Marques, J. C. 2004Dynamic changes in seagrass assemblages under eutrophication and implications for recoveryJournal of Experimental Marine Biology and Ecology302233248CrossRefGoogle Scholar
  7. Clarke, K. R. 1993Nonparametric multivariate analyses of changes in community structureAustralian Journal of Ecology18117143Google Scholar
  8. Deegan, L. A., Wright, A., Ayvazian, S. G., Finn, J. T., Golden, H., Merson, R. R., Harrison, J. 2002Nitrogen loading alters seagrass ecosystem structure and support of higher trophic levelsAquatic Conservation: Marine and Freshwater Ecosystems12193212CrossRefGoogle Scholar
  9. Duarte, C. M. 1995Submerged aquatic vegetation in relation to different nutrient regimesOphelia4187112Google Scholar
  10. Dyer, L. A., Stireman, J. O.,III 2003Community-wide trophic cascades and other indirect interactions in an agricultural communityBasic and Applied Ecology4423432CrossRefGoogle Scholar
  11. Ferdie, M., Fourqurean, J. W. 2004Responses of seagrass communities to fertilization along a gradient of relative availability of nitrogen and phosphorus in a carbonate environmentLimnology and Oceanography4920822094CrossRefGoogle Scholar
  12. Fourqurean, J. W., Durako, M. J., Hall, M. O., Hefty, L. N. 2002

    Seagrass distribution in South Florida: a multi-agency coordinated monitoring program

    Porter, J. W.Porter, K. G. eds. The Everglades, Florida Bay, and Coral Reefs of the Florida Keys: An Ecosystem SourcebookCRC PressBoca Raton497522
    Google Scholar
  13. Fourqurean, J. W., Powell, G. V. N., Kenworthy, W. J., Zieman, J. C. 1995The effects of long-term manipulation of nutrient supply on competition between the seagrasses Thalassia testudinum and Halodule wrightii in Florida BayOikos72349358Google Scholar
  14. Fourqurean, J. W., Zieman, J. C. 2002Nutrient content of the seagrass Thalassia testudinum reveals regional patterns of relative availability of nitrogen and phosphorus in the Florida Keys USABiogeochemistry61229245CrossRefGoogle Scholar
  15. Frankovich, T. A., Zieman, J. C. 2005A temporal investigation of grazer dynamics, nutrients, seagrass leaf productivity, and epiphyte standing stockEstuaries284152Google Scholar
  16. Goecker, M. E., Heck, K. L. J., Valentine, J. F. 2005Effects of nitrogen concentrations in turtlegrass Thalassia testudinum on consumption by the bucktooth parrotfish Sparisoma radiansMarine Ecology Progress Series286239248Google Scholar
  17. Hauxwell, J., Cebrian, J., Furlong, C., Valiela, I. 2001Macroalgal canopies contribute to eelgrass (Zostera marina) decline in temperate estuarine ecosystemsEcology8210071022CrossRefGoogle Scholar
  18. Hays, C. G. 2005Effect of nutrient availability, grazer assemblage and seagrass source population on the interaction between Thalassia testudinum (turtle grass) and its algal epiphytesJournal of Experimental Marine Biology and Ecology3145368CrossRefGoogle Scholar
  19. Hemmi, A., Jormalainen, V. 2002Nutrient enhancement increases performance of a marine herbivore via quality of its food algaEcology8310521064CrossRefGoogle Scholar
  20. Howarth, R. W. 1988

    Nutrient limitation of net primary production in marine ecosystems

    Johnston, R. F. eds. Annual Review of Ecology and SystematicsAnnual Reviews, IncPalo Alto, CA89110
    Google Scholar
  21. Hughes, A. R., Bando, K. J., Rodriguez, L. F., Williams, S. L. 2004Relative effects of grazers and nutrients on seagrasses: a meta-analysis approachMarine Ecology Progress Series2828799Google Scholar
  22. Hunter, M. D., Price, P. W. 1992Playing chutes and ladders: heterogeneity and the relative roles of bottom-up and top-down forces in natural communitiesEcology73724732Google Scholar
  23. Isaksson, I., Pihl, L. 1992Structural changes in benthic macrovegetation and associated epibenthic faunal communitiesNetherlands Journal of Sea Research30131140CrossRefGoogle Scholar
  24. Keats, R. A., Osher, L. J., Neckles, H. A. 2004The effect of nitrogen loading on a brackish estuarine faunal community: a stable isotope approachEstuaries27460471Google Scholar
  25. Krebs, C. J. 1994Ecology: The Experimental Analysis of Distribution and Abundance4Addison-Wesley Publishers, IncMenlo Park, CAGoogle Scholar
  26. Leibold, M. A. 1999Biodiversity and nutrient enrichment in pond plankton communitiesEvolutionary Ecology Research17395Google Scholar
  27. McManus, J. W., Polsenberg, J. F. 2004Coral-algal phase shifts on coral reefs: ecological and environmental aspectsProgress in Oceanography60263279CrossRefGoogle Scholar
  28. Moncreiff, C. A. & M. J. Sullivan, 2001. Trophic importance of epiphytic algae in subtropical seagrass beds: evidence from multiple stable isotope analyses. Marine Ecology Progress Series: 93–106Google Scholar
  29. Nixon, S. W. 1995Coastal marine eutrophication: a definition, social causes, and future concernsOphelia41199219Google Scholar
  30. Nixon, S. W., Buckley, B. A. 2002“A strikingly rich zone” – nutrient enrichment and secondary production in coastal marine ecosystemsEstuaries25782796Google Scholar
  31. Ostertag, R., Verville, J. H. 2002Fertilization with nitrogen and phosphorus increases abundance of non-native species in Hawaiian montane forestsPlant Ecology1627790CrossRefGoogle Scholar
  32. Parker, J. D., Duffy, J. E., Orth, R. J. 2001Plant species diversity and composition: experimental effects on marine epifaunal assemblagesMarine Ecology Progress Series2245567CrossRefGoogle Scholar
  33. Pinckney, J. L., Paerl, H. W., Harrington, M. B. 1999Responses of the phytoplankton community growth rate to nutrient pulses in variable estuarine environmentsJournal of Phycology3514551463CrossRefGoogle Scholar
  34. Posey, M. H., Alphin, T. D., Cahoon, L. B., Lindquist, D. G., Mallin, M. A., Nevers, M. B. 2002Top-down versus bottom-up limitation in benthic infaunal communities: direct and indirect effectsEstuaries259991014CrossRefGoogle Scholar
  35. Short, F. T., Burdick, D. M., Kaldy, J. E. 1995Mesocosm experiments quantify the effects of eutrophication on eelgrass, Zostera marinaLimnology and Oceanography40740749Google Scholar
  36. Smith, V. H., Tilman, G. D., Nekola, J. C. 1999Eutrophication: impacts of excess nutrient inputs on freshwater, marine, and terrestrial ecosystemsEnvironmental Pollution100179196PubMedCrossRefGoogle Scholar
  37. Tolan, J. M., Holt, S. A., Onuf, C. P. 1997Distribution and community structure of ichthyoplankton in Laguna Madre seagrass meadows: potential impact of seagrass species changeEstuaries20450464CrossRefGoogle Scholar
  38. Valiela, I., McClelland, J., Hauxwell, J., Behr, P. J., Hersh, D., Foreman, K. 1997Macroalgal blooms in shallow estuaries: controls and ecophysiological and ecosystem consequencesLimnology and Oceanography4211051118CrossRefGoogle Scholar
  39. Valiela, I., Rutecki, D., Fox, S. 2004Salt marshes: biological controls of food webs in a diminishing environmentJournal of Experimental Marine Biology and Ecology300131159CrossRefGoogle Scholar
  40. Widbom, B., Elmgren, R. 1988Response of benthic meiofauna to nutrient enrichment of experimental marine ecosystemsMarine Ecology Progress Series42257268Google Scholar
  41. Williams, S. L., Ruckelshaus, M. H. 1993Effects of nitrogen availability and herbivory on eelgrass (Zostera marina) and epiphytesEcology74904918CrossRefGoogle Scholar
  42. Wootton, J. T., Power, M. E., Paine, R. T., Pfister, C. A. 1996Effects of productivity, consumers, competitors, and El Niño events on food chain patterns in a rocky intertidal communityProceedings of the National Academy of Sciences of the United States of America931385513858PubMedCrossRefGoogle Scholar
  43. Zupo, V., Nelson, W. G. 1999Factors influencing the association patterns of Hippolyte zostericola and Palaemonetes intermedius (Decapoda: Natantia) with seagrasses of the Indian River Lagoon, FloridaMarine Biology134181190CrossRefGoogle Scholar

Copyright information

© Springer 2006

Authors and Affiliations

  • Melissa Gil
    • 1
  • Anna R. Armitage
    • 1
  • James W. Fourqurean
    • 1
  1. 1.Department of Biological Sciences and Southeast Environmental Research CenterFlorida International UniversityMiamiUSA

Personalised recommendations