Fig. 5. Seasonal fluctuations in 

 population of diatoms (D, cl/«,) and 

 veliger gastropods (V, 10^ indiv.), 

 settling each month onto an area of 

 1 m^ (according to Glynn, 1973). 



nr I I m m 7 m m m a x 



of the bacterial population, that iL furms aggregations in the pro.. ess 

 of multiplying (Sorokin, 1971a, b, 1973c), rather than a result of the 

 cementing effect of the coral mucus, as was assumed earlier (N.B. 

 Marshall, 1968; Johannes, 1967). 



The maximum values of biomass of bacterioplankton avq usually noted 

 in the shore zone, where the surf washes the microflora from the bottom 

 sediments, and also in the frontal zone of the reef (Br-FR zones). Here 

 also, we frequently see the greatest value of bacterial production. The 

 values of daily production of bacterioplankton varied within limits of 

 10-50 mg C/m^, the daily P/B ratio was 0.2-0.4 in the lagoon and 0.5-2 

 over the outer slope of the reef. The low values of P/B coefficient in 

 the lagoon, particularly along the shore, atq. apparently related to the 

 input of a large quantity of benthic microflora, slowing the 

 multiplication rate in the water column. 



The information available on the zooplankton of the reef waters is 

 sparse and contradictory (Johannes et al., 1970; Emery, 1968; Glynn, 

 1973). It is difficult to observe, since most of it hides during the 

 day in the sand and in stands of macrophytes, and appears in the water 

 only at night. Also, the biomass of mesozooplankton on the reefs is 

 subject to great seasonal variation (Fig. 5), since a significant 

 portion of it consists of the meroplanktonic larvae of benthic animals 

 (M. J. Allen, 1957). Data on the biomass and seasonal changes in 

 organisms of the microzooplankton (nauplial stages of copepoda, 

 infusoria) are severely lacking. 



The coral communities d^vQ inhabited by a rich and varied 

 ichthiofauna. A significant portion consists of benthophages, which 

 feed along with benthic animals also on detritus, algae, periphyton, and 

 also living corals. The biomass of fish in reefs was estimated as 100- 

 300 kg/ha (Glynn, 1973). The planktonophagous fish inhabiting the area 

 around reefs is dominated by juvenile oceanic pelagic species, which 

 find good feeding conditions here. 



182 



