A temporal investigation of grazer dynamics, nutrients, seagrass leaf productivity, and epiphyte standing stock Article

cited authors

  • Frankovich, TA; Zieman, JC

fiu authors

abstract

  • An investigation of seagrass-epiphyte controlling factors was conducted within a Thalassia testudinum meadow in Florida Bay from March 2000 to April 2001. Univariate and multivariate analyses were performed using water column nutrient concentrations, temperature, salinity, and turbidity, and gastropod grazer abundances, seagrass leaf area index, and leaf turnover rate data to explain the variation in total epiphyte standing stock, epiphyte chlorophyll a, and epiphyte autotrophic index. Turbidity was positively correlated with total epiphyte standing stock and accounted for the most variation. Observations of adhered sediment on T. testudinum leaves and the combination of increased total epiphyte standing stocks and low autotrophic indices observed in February and April 2001 suggest that the settling of resuspended sediments following turbidity events is one of the temporal mechanisms for increased epiphyte accumulation. Total epiphyte standing stock was also negatively correlated with the abundance of a robust gastropod grazer community dominated by Turbo castanea, Tegula fasciata, and Modulus modulus. Distinct temporal size cohorts of T. castanea and T. fasciata throughout the study period suggest recruitment in spring and an annual lifespan. Nutrient concentrations can also account for some of the temporal variation in total epiphyte standing stock, epiphyte chlorophyll a, and autotrophic index. The low variation of T. testudinum leaf turnover rates was unable to account for any of the variation in the epiphyte parameters. © 2005 Estuarine Research Federation.

publication date

  • January 1, 2005

Digital Object Identifier (DOI)

start page

  • 41

end page

  • 52

volume

  • 28

issue

  • 1