Development and Application of the SEDCON Index for Resource and Risk Assessment of Coral Ecosystems
Abstract
Resource managers need inexpensive bioindicators to evaluate the health of coral ecosystems and to guide decisions on when and where to utilize more expensive assessment techniques. Following USEPA Guidelines for Evaluating Ecological Indicators, we are developing a rapid-assessment protocol, termed the SEDCON Index (SI), that utilizes reef sediment constituents to assess the integrity of coral-reef communities. Key advantages of this index are that it only requires small sediment samples and is applicable to reefs worldwide. The underlying assumption of the index is that community structure is reflected by proportions of recognizable remnants of calcareous shells and skeletal remains of autotrophic (calcareous and coralline algae), mixotrophic (zooxanthellate corals and larger foraminifers) and heterotrophic (e.g., bryozoans, molluscs, smaller foraminifers) benthic organisms, and of unrecognizable debris as a proxy for bioerosion. Implementation and assessment of this diagnostic tool is currently underway for the Florida Middle Grounds (FMG) and the Coral Reef Monitoring Program (CRMP) sites in the Florida Keys National Marine Sanctuary (FKNMS). We are calibrating SI data with benthic community data from CRMP. Data from samples collected in FKNMS between 2001 and 2004 indicate dominance of the sediments by bioerosional debris, while data from samples collected in the early 1980s from the FKNMS and from the FMG in 2003 indicate higher proportions of identifiable components of mixotrophic origin. Application of the SI provides an assessment of ecosystem condition on scales of years and will be used to supply reef baseline data for detecting changes associated with the Comprehensive Everglades Restoration Plan.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2004
- Bibcode:
- 2004AGUFMOS51C1312D
- Keywords:
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- 4815 Ecosystems;
- structure and dynamics;
- 4894 Instruments and techniques