Details:

Journal Title:
Coral Reefs
Personal Author:
Storlazzi, C. D. ; Cheriton, O. M. ; Messina, A. M. ; Biggs, T. W.
Storlazzi, C. D. ; Cheriton, O. M. ; Messina, A. M. ; Biggs, T. W. Less -
NOAA Program & Office:
NOS (National Ocean Service) ; CoRIS (Coral Reef Information System)
NOS (National Ocean Service) ; CoRIS (Coral Reef Information System) Less -
Description:
Water circulation over coral reefs can determine the degree to which reef organisms are exposed to the overlying waters, so understanding circulation is necessary to interpret spatial patterns in coral health. Because coral reefs often have high geomorphic complexity, circulation patterns and the duration of exposure, or “local residence time” of a water parcel, can vary substantially over small distances. Different meteorologic and oceanographic forcings can further alter residence time patterns over reefs. Here, spatially dense Lagrangian surface current drifters and Eulerian current meters were used to characterize circulation patterns and resulting residence times over different regions of the reefs in Faga’alu Bay, American Samoa, during three distinct forcing periods: calm, strong winds, and large waves. Residence times varied among different geomorphic zones of the reef and were reflected in the spatially varying health of the corals across the embayment. The relatively healthy, seaward fringing reef consistently had the shortest residence times, as it was continually flushed by wave breaking at the reef crest, whereas the degraded, sheltered, leeward fringing reef consistently had the longest residence times, suggesting this area is more exposed to land-based sources of pollution. Strong wind forcing resulted in the longest residence times by pinning the water in the bay, whereas large wave forcing flushed the bay and resulted in the shortest residence times. The effect of these different forcings on residence times was fairly consistent across all reef geomorphic zones, with the shift from wind to wave forcing shortening mean residence times by approximately 50%. Although ecologically significant to the coral organisms in the nearshore reef zones, these shortened residence times were still 2–3 times longer than those associated with the seaward fringing reef across all forcing conditions, demonstrating how the geomorphology of a reef environment sets a first-order control on reef health.
Keywords:
[+]
Aquatic Science
Source:
Coral Reefs, 37(2), 457-469
DOI:
https://doi.org/10.1007/s00338-018-1671-4
ISSN:
0722-4028;1432-0975;
Format:
PDF
Publisher:
Springer Science and Business Media LLC
Document Type:
Journal Article
Funding:
Grant no. NA13NOS4820025
License:
https://creativecommons.org/publicdomain/zero/1.0/
Rights Information:
CC0 Public Domain
Compliance:
Library
Main Document Checksum:
[+]
urn:sha256:ef06b8105b7807d09860ad1da7cdc8738f7576f997b7e535e9f68b8dabf57c42
Download URL:
https://repository.library.noaa.gov/view/noaa/59603/noaa_59603_DS1.pdf
File Type:

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