DeGeorges A.,Global Coral Reef Alliance |
DeGeorges A.,Tshwane University of Technology |
Goreau T.J.,Global Coral Reef Alliance |
Reilly B.,Tshwane University of Technology
Sustainability | Year: 2010
This paper discusses land-sourced pollution with an emphasis on domestic sewage in the Caribbean in relation to similar issues in the Indian Ocean and Pacific. Starting on a large-scale in the 1980s, tropical Atlantic coastlines of Florida and Caribbean islands were over-developed to the point that traditional sewage treatment and disposal were inadequate to protect fragile coral reefs from eutrophication by land-sourced nutrient pollution. This pollution caused both ecological and public health problems. Coral reefs were smothered by macro-algae and died, becoming rapidly transformed into weedy algal lawns, which resulted in beach erosion, and loss of habitat that added to fisheries collapse previously caused by over-fishing. Barbados was one of the first countries to recognize this problem and to begin implementation of effective solutions. Eastern Africa, the Indian Ocean Islands, Pacific Islands, and South East Asia, are now starting to develop their coastlines for ecotourism, like the Caribbean was in the 1970s. Tourism is an important and increasing component of the economies of most tropical coastal areas. There are important lessons to be learned from this Caribbean experience for coastal zone planners, developers, engineers, coastal communities and decision makers in other parts of the world to assure that history does not repeat itself. Coral reef die-off from land-sourced pollution has been eclipsed as an issue since the ocean warming events of 1998, linked to global warming. Addressing ocean warming will take considerable international cooperation, but much of the land-sourced pollution issue, especially sewage, can be dealt with on a watershed by watershed basis by Indian Ocean and Pacific countries. Failure to solve this critical issue can adversely impact both coral reef and public health with dire economic consequences, and will prevent coral reef recovery from extreme high temperature events. Sewage treatment, disposal options, and nutrient standards are recommended that can serve as a reference point but must be fine-tuned to local ecology. © 2010 by the authors; licensee MDPI, Basel, Switzerland.
Stromberg S.M.,Gothenburg University |
Lundalv T.,Gothenburg University |
Goreau T.J.,Global Coral Reef Alliance
Journal of Experimental Marine Biology and Ecology | Year: 2010
Extensive areas of the cold-water scleractinian Lophelia pertusa have been damaged due to the impact of bottom-trawling and natural recovery is slow or absent. Here we evaluate a method for coral reef rehabilitation intended to enhance coral transplant survival and growth, i.e. mineral accretion by electrolysis in seawater. Electrolysis in seawater produces a semi-natural substrate in the form of aragonite (CaCO 3). The method has been used in coral reef rehabilitation programmes in tropical coral habitats but has so far not been tested in temperate deep-water habitats. A controlled laboratory experiment was performed to test the effect of the substrate per se and different levels of applied current densities (0.00-2.19Am -2), including galvanic elements (Fe|Zn), on coral fragments attached to the cathodes. The studied responses were; growth rate, budding frequency, mortality, and general health status (degree of polyp activity). We found that the budding frequency differed significantly between treatments, with higher frequencies in low current density treatments. Significant differences were also found in the frequency distribution of calices displaying a growth of ≥2mmyr -1, with higher frequencies in the lowest applied current density (LI), controls, and galvanic elements. Growth rates were slightly higher in LI, although non-significant. Zero mortality was observed in the control group as well as in LI. The degree of polyp activity was not affected by the treatments. These results are in part congruent with earlier studies and the method is found suitable for L. pertusa. The positive effects were mainly restricted to the lowest applied current density treatment (0.06Am -2). The optimal current density level is hereby found to be considerably lower than levels used in previous studies and provide new guidelines for what levels to use in rehabilitation programmes with this method. © 2010 Elsevier B.V.
Wells L.,Grand Turk |
Perez F.,Grand Turk |
Hibbert M.,Grand Turk |
Clerveaux L.,Grand Turk |
And 2 more authors.
Revista de Biologia Tropical | Year: 2010
Artificial reefs are often discouraged in shallow waters over concerns of storm damage to structures and surrounding habitat. Biorock coral reef restoration projects were initiated in waters around 5m deep in Grand Turk, at Oasis (October 2006) and at Governor's Beach (November 2007). Hemi-cylindrical steel modules, 6m long were used, four modules at Oasis and six at Governor's Beach. Each project has over 1200 corals transplanted from sites with high sedimentation damage, and are regularly monitored for coral growth, mortality and fish populations. Corals show immediate growth over wires used to attach corals. Growth has been measured from photographs using a software program and is faster at Governor's Beach. After hurricanes Hanna and Ike (September 2008) the Governor's Beach structure was fully standing since the waves passed straight through with little damage, the Oasis structures which were tie-wired rather than welded had one module collapse (since been replaced with a new, welded structure). Hurricane Ike was the strongest hurricane on record to hit Grand Turk. Most cables were replaced following the hurricanes due to damage from debris and high wave action. The projects lost about a third of the corals due to hurricanes. Most of those lost had only been wired a few days before and had not yet attached themselves firmly. These projects have regenerated corals and fish populations in areas of barren sand or bedrock and are now attractive to snorkelers. High coral survival and low structural damage after hurricanes indicate that Biorock reef restoration can be effective in storm-impacted areas.