organic matter in the waters of the ocean--dbout 2 mg C/£--is controlled 

 to some extent by the periodic passage of the entire volume of water in 

 the world ocean over coral reefs as global circulation occurs. 

 According to our calculations, the time required for this process is not 

 so great in the geologic scale of time: about 40,000 years. 



Investigators studying coral biogeocenoses report a high degree of 

 maturity of the coral reef ecosystems (Grassle, 1973). The signs of 

 maturity include the predominance of long-living forms with slow growth 

 rates, as well as the high predictability of conditions of the growth 

 medium and a high degree of specialization of many mass species which we 

 mentioned earlier (Golikov et al., 1972). The maturity of the reef 

 community is also revealed as we analyze the inherent complex 

 interactions between organisms as, for example, the hierarchy of 

 antagonistic interactions between corals (Lang, 1973), as well as the 

 developed ecologic metabolism. 



The maturity of the reef biogeocenosis is also manifested in the 

 close energy interaction of the component communities. This interaction 

 basically follows two paths. The first path is the transfer of 

 dissolved organic matter liberated by autotrophs, detritus, periphyton 

 and benthic bacteria and algae, washed by the surf from the epibiotic 

 associations and bottom sediments. The tide currents over the reef are 

 mostly of an advancing and retreating nature. As the tide rises, 

 practically the same water which left the reef when the tide fell 

 returns to it. At low tide, the water leaving the reef passes over its 

 frontal slope, where an intensive multiplication of microplankton 

 occurs, and is held there. Therefore, the corals and other benthic 

 filter feeders and sediment feeders, living on the outer slope of the 

 reef, can utilize the energy reserves of the organic suspended matter 

 washed from the shallow zone of the reef. Another path in the trophic 

 connection of the biotope of the outer slope with the shallow zone is 

 the "runoff" of detritus, bottom sediments and clastic material in the 

 direction of the fore-reef. At the same time, the corals and macroalgae 

 growing abundantly on the outer slope enrich the water with dissolved 

 organic matter, which is carried by the tidal flow into the shallow 

 portion of the reef and there consumed by the periphyton microflora. We 

 must, therefore, consider the point of view (Yonge, 1963; Ladd, 1969) 

 that the biotopes of the outer slope of the reef Are not connected in 

 any way with the biotopes of the shallow portion of the reef (reef flat 

 and lagoon) to be incorrect. 



The complex and intensively functioning ecosystem of the coral reef 

 is \iery sensitive to anthropogenic effects: pollution, eutrophication , 

 overfishing. Pollution and eutophication result in a shift of the cycle 

 of organic matter in the direction of predominance of destructive 

 processes, decrease of the oxygen content, development of the process of 

 reduction of sulfates to hydrogen sulfide, appearance of reducing 

 sediment. All of this may cause massive death of corals and of the 

 fauna which populate it, rapid development of macrophytes, Zoantharia 

 and Actinia , which inhibit the growth of corals and replace them 

 (DiSalvo, 1973i Banner, 1974; Sorokin, 1971b, Sorokin, 1973b). It is 

 thought that the harvesting for their beautiful shells of large numbers 

 of some gastropod mollusks such as Hazonia tritonis, which are the 



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