Published In

Ecosystems

Document Type

Article

Publication Date

4-2009

Subjects

Mangrove forests, Seagrasses, Coastal zone management, Mangrove ecology, Coral reefs and islands, Stable isotopes in ecological research

Abstract

Coastal mangrove forests were historically considered as a source of organic matter (OM) for adjacent marine systems due to high net primary production; yet recent research suggesting little uptake through the food web because of low nutritional quality, challenges the concept of trophic linkage between mangrove forests and coral reefs. To examine the importance of mangrove forests to coral reef nutrient availability, we examined sessile reef-forming invertebrate consumers including hard corals, sponges, a bivalve mollusc, polychaete annelid and tunicate, and potential sources of OM (decaying mangrove leaves, microalgae, macroalgae, and seagrass) in Bocas del Toro, Panama. Using stable isotope analyses of δ34S and δ13C and a concentration-dependent version of the IsoSource mixing model, we were able to discriminate among and determine the range of potential contributions of our four OM sources to consumers. Contributions of microalgae and macroalgae were often indeterminate due to high variability, yet seagrass and mangrove contributions were often substantial. Mangrove OM ranged across sites and species of filter feeders from 0 to 57%, 7 to 41%, and 18 to 52% for sponges, file clams, and feather duster worms, respectively. Mangrove contribution to corals (Acropora cervicornis, Agaricia fragilis, Agaricia tenuifolia, Montastrea annularis, Diploria sp.) ranged from 0 to 44%. To examine whether OM contribution varied with distance from mangroves, we conducted a sponge transplant experiment that demonstrated declining mangrove contribution across three sponge species with increasing distance from the shore. These results supported the hypothesis of mangrove-coral reef nutrient linkages, providing the first evidence that mangrove inputs of OM to sessile invertebrates are substantial, accounting for 0–57% of the composition.

Description

To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final PDF. The published article is copyrighted by Ecosystems and can be found at: http://dx.doi.org/10.1007/s10021-009-9235-7

DOI

10.1007/s10021-009-9235-7

Persistent Identifier

http://archives.pdx.edu/ds/psu/12341

Share

COinS