ISSN:
1432-0975
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Geosciences
Notes:
Abstract Damage caused by catastrophic storm waves and subsequent recovery was investigated with a series of 15 line transects on a reef off the west coast of Hawaii over a 20-year period (1973–1993). At the initiation of the study, four zones existed across the reef, each defined by a different dominant coral species. An intermediate intensity storm in 1974 caused a decrease in coral cover from 52% to 46% of bottom cover, while breakage and transport of fragments extended the depth of peak coral cover. In 1980, a “Kona” storm, which generated the largest storm surf on record, destroyed the coral zonation pattern almost entirely. Living coral was reduced from 46% to 10% of bottom cover, with greatest damage in the zones with highest cover. Twelve years later (1992), living coral cover increased to 15% of total bottom cover. Lack of significant correlation between increase of coral cover and initial cover indicated that recovery was from larval settlement, rather than regeneration of viable fragments. Extrapolation of recovery from 1980 to 1992 indicates that the pre-storm (1973) conditions would be reached in 40 years (exponential growth) to 70 years (linear growth). In 1993, following a hurricane and unusually large northwest swell, coral cover was once again reduced to 11%; recovery was set back to a level similar to that in 1980 following the Kona storm. In 1992 and 1993 no evidence of CaCO3 accretion was observed on the reef bench. Rubble fragments created by storm stress were deposited on the reef slope with little subsequent lithification. While hurricane force waves may occur very infrequently in Hawaii, this source of stress appears to effectively limit Holocene reef growth in all areas except sheltered embayments. The pattern of damage and recovery of this coral ecosystem conforms to the intermediate disturbance hypothesis, in which storms of intermediate intensity produce either an increase or decrease in diversity and cover, depending on the timing of severe storms. On a global scale, timescales of damage and recovery cycles vary substantially depending on the frequency of severe disturbances, and the adaptive capabilities of dominant species.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00334481
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