Coral reef restoration and artificial reef management, future and economic.

On a global scale, the value of the total economic goods and services provided by coral reefs have been esti- mated to be US$375 billion per year with most of this coming from recreation, sea defence services and food production, this equates to an average value of around US$6,075 per hectare of coral reef per year. Degradation of reefs means the loss of these economic goods and services, and the loss of food security and employment for coastal peoples, many of them in developing countries and many of them living in poverty. In a healthy reef system which has not been physically damaged, an impacted area might be expected to recover naturally to its pre-disturbance state along a successional trajec- tory. If degradation is sufficiently severe or spatially extensive, then active restoration e.g. transplantation, in combination with management actions to reduce anthropogenic stress are necessary. Recoverability depends on the stressor, the im- pacted species/community and the temporal and spatial intensities of the stressor. Artificial reef is any structure built or placed on the sea bed, water column or floating on its surface, with the purpose of creating a new attraction to scuba di- vers or to concentrate or attract plants or animals for fishing purposes. These artificial reefs can be designed for different purposes like: (1) Tourism {SCUBA diving, recreational angling, surfing and beach enhancement} (2) Fisheries (3) Na- ture conservation (4) Science. This paper reviews conditions driving the need for restoration, and the questions that must be considered to identify the type of restoration necessary or possible. Artificial reefs around the world, their uses, social and economic impacts, liability, the use of novel technology approaches in artificial reefs and future applications were also reviewed. Artificial reefs can have positive economic impacts which are significant and may be several hundreds of million dollars per year. For future application, need is urgent for: 1- Link biological, physical and economic issues within reef development 2- Continue biological and engineering research to refine reef design and modeling.