The economy of Vietnam is developing rapidly. The coastline of Vietnam has become a site of intense house- and road-building; dozens of new hotels and diving centers have recently appeared here, and sea farming is developing extensively. This intensification has become a cause of increased terrigenous effluent into waters of local bays. Local coral reefs are subjected to deposition of 70-100 g/m2 a day, and this estimate grows one order higher during typhoons (Vo, Hodgson,1997; 2003). Erosion processes along the coastal line at the city and port of Nha Trang, as well as developing sea farming in coastal waters of neighboring islands, aggravate the sedimentation and eutrophication impact in Nha Trang Bay. (An et aI., 2000; 2004). An increased amount of microparticles of different origins increases water turbidity caused by deposition, leads to impairment of photosynthetic abilities of reef building corals and other benthic organisms, and reduces physical and biological processes in the sea (Soong, Chen, 2003). As a result, coral cover of the substrate reduces to 20-40 percent, while the portion of substrate cover by macrophytes Chnoospora and Halimeda grows to 60-80 percent: General reduction of the area of coral reefs has recently been documented (Latypov, 2006). Many publications are available on transplantation and cultivation of coral fragments; they cover various methodical, physical and biological problems connected with coral cultivation. A majority of researchers believe that the attention of those engaged in the matter should be focused on the size of coral fragments, the season of their transplantation, orientation in the place of transplanting, and selection of substrate. These factors are most important for restoration of reproductive abilities of new coral colonies reared from fragments (Okubo, 2005). Based on the positive experience in cultivation of corals, the authors analyzed presumably species-specific peculiarities of regeneration of fragments and growth of new coral colonies of the genera Acropora and Porites, belonging to the families Acroporidae and Poritidae.
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