The recovery process in a mechanically damaged coral reef community /
| Main Author: | |
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| Other Authors: | , , , |
| Format: | Book |
| Language: | English |
| Published: |
1988.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | The recovery of an upper forereef coral community on Molasses Reef (Florida Keys), damaged by the grounding of a 122 m freighter, was studied over a 27 month period following the removal of the vessel. Regrowth of tissue on damaged corals was negligible, suggesting that recovery will depend largely on coral recruitment. Over 90% of the hard corals and 98% of the gorgonians in the most heavily damaged area of the reef (1500 m a) were destroyed. Damage consisted of fracturing, crushing, toppling, and abrading of large and small coral heads, and prolonged shading of some coral heads, resulting in zooxanthellae expulsion. In one area of moderate damage (850 m a), 42-53% of hard corals and 50-70% of the gorgonians were destroyed. Rubble produced by the grounding caused further damage during a hurricane one year after the incident, and substratum instability may have delayed recruitment. Recruitment may also have been delayed by loose sediments produced by the ship. Along with rubble, these sediments were largely removed by the hurricane. This stabilized the substratum and increased micro habitat availability, increasing successful recruitment. Recruitment was 2-6 times higher in areas only moderately damaged by the grounding than in maximally disturbed areas or control areas, suggesting 1- that proximity to adult corals affects local recruitment, 2- that recolonization rates may be more influenced by local recruitment than by recruitment of larvae dispersed over long distances, and 3- that space limitation may control recruitment in undamaged areas. Some recovery in the heavily damaged area has resulted in abundances 10% and 13% of pre-impact hard corals and gorgonian populations, respectively; recovery to pre-impact numerical abundances may require more than two decades. This recovery time estimate decreases, however, to approximately one decade if one uses recruitment rates achieved following Hurricane Kate, which were higher than estimates made prior to the storm. Complete recovery in moderately impacted areas may require less than 10 years. The dominant colonizing species have been those present in surrounding undamaged areas... |
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| Item Description: | Vita. "Major subject: Oceanography." |
| Physical Description: | xv, 228 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references (leaves 213-227). |