Oecologia

, Volume 148, Issue 2, pp 334–341

Stable isotope analysis of production and trophic relationships in a tropical marine hard-bottom community

Authors

  • Donald C. Behringer
    • Department of Biological SciencesOld Dominion University
    • Department of Biological SciencesOld Dominion University
Community Ecology

DOI: 10.1007/s00442-006-0360-0

Cite this article as:
Behringer, D.C. & Butler, M.J. Oecologia (2006) 148: 334. doi:10.1007/s00442-006-0360-0

Abstract

Seagrasses produce much of the organic carbon in the shallow waters of the Caribbean and it has long been assumed that a substantial portion of this carbon is exported to nearby habitats, contributing substantially to their food webs. In the shallow coastal waters of the Florida Keys (USA), seagrass intersperses with hard-bottom habitat where bushy, red macroalgae are the most prominent primary producers. However, the relative importance of seagrass-derived carbon versus autochthonous algal production or phytoplankton in supporting higher trophic levels within hard-bottom communities has never been investigated. We compared the carbon and nitrogen isotopic values of potential primary producers and representative higher trophic level taxa from hard-bottom sites on the bay-side and ocean-side of the Florida Keys. We also included in our study a set of bay-side sites that experienced significant ecological disturbances over the past decade (e.g., cyanobacteria blooms, seagrass die-off, and sponge die-offs) that may have altered trophic relationships in those regions. We did not detect any differences among regions in the trophic status of hard-bottom taxa that might be associated with ecosystem disturbance. However, our results suggest that autochthonous production of algal detritus is an important source of secondary production in these hard-bottom communities, with seagrass and phytoplankton contributing smaller fractions.

Keywords

Benthic communityLaurenciaMacroalgaeSeagrassTrophic structure

Copyright information

© Springer-Verlag 2006