Bacteria in the open water

With the exception of autotrophic bacteria which contribute a negligible amount of organic matter to the global primary productivity, the interest in the position of non-auto trophic bacteria as secondary producers of organic matter over recent years warrants the treatment of this subject in a separate section. 

Possible reasons for the lack of temporal correlation became more apparent as mechanisms for the production of particulate matter were discovered (Pomeroy, 1974 Wangersky, 1977). All of these mechanisms involve the collection of surface-active material, either in solution or in the form of colloidal micelles, at an interface, followed by compression of the interface, both gas-liquid interfaces and liquid—solid interfaces (Wangersky, 1977). Nevertheless, the formation and ultimate fate of organic particles in situ is still poorly understood (Conover, 1978). 

There is little doubt that marine bacteria are closely associated with the particulate matter. Microorganisms, however, are not concentrated on the particulate matter, almost every investigator, according to Wangersky (1977), has found that as much as 80% of the bacteria in the water column are to be 

There is much discrepancy in literature concerning the extent of bacterial productivity in the sea. Whittaker and Likens (1973) demonstrated a theoretical approach in treating the biosphere as a system in steady state in which total respiration of all heterotrophic organisms essentially equals total net primary productivity. Given this equality, total reducer (bacterial and fungal) assimilation should approximately equal net primary production minus animal assimilation. With an assumed growth efficiency of 5—10% for marine reducers, then marine reducer production would be 0.7 to 1.4 X 10 t C yr , or about half to about the same as the authors estimated marine animal production (= 1.376 X 10 t C yr ). 

Ferguson and Rublee (1976) estimated the amount of bacterial carbon in coastal waters as ranging between 4% and 25% of total plankton carbon biomass. Meyer-Reil (1977), using highly sensitive methods to determine the growth of bacteria under semi-natural conditions, arrived at an average bacterial biomass production in Kiel Fjord and Bight (Baltic) of 15 29% of the phytoplankton primary production. Such values may indeed approach reality. 

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