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Title: Oyster Reef Restoration May Influence Local Sediment Geochemistry Prior to Introduction of Live Oysters

Oyster reefs provide crucial ecosystem services, but their populations are declining worldwide. Oyster reef restoration efforts are underway in many regions, including the Gulf Coast of the United States, where the intertidal oyster populations of the eastern oyster, Crassostrea virginica, have experienced significant declines. A novel method of restoration aimed at decreasing oyster mortality from predators through induction of predatory defenses has been implemented in coastal Alabama. The first step in this novel oyster reef restoration method is the deployment of a base layer of uninhabited oyster shells directly on the sediment prior to the introduction of live oysters. This study evaluated the impacts of the first step of this novel method of restoration, construction of the reef structure, on local sediment physicochemical characteristics. Results indicate that the vertical structure of the oyster reef affects sediment grain size and physicochemical properties. After 47 days, sediment pH increased from 8.29 ± 0.04 to 8.86 ± 0.03 with a concomitant increase in calcium carbonate from 0.509 ± 0.021 % to 0.818 ± 0.112 %. Despite many positive geochemical effects of oyster reef restoration being mediated by the presence of live oysters, the increased pH and calcium carbonate demonstrated herein represent more ideal conditions for oyster growth and survivability, potentially increasing the long-term efficacy of oyster reef restoration via this method.

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Award ID(s):
2150347
NSF-PAR ID:
10494141
Author(s) / Creator(s):
; ;
Publisher / Repository:
The University of Southern Mississippi, Aquila
Date Published:
Journal Name:
Gulf and Caribbean Research
Volume:
34
ISSN:
2572-1410
Page Range / eLocation ID:
SC40 to SC44
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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