Microbial processes anaerobic incubations

The rate of methylation of mercury in anaerobically incubated estuarine sediments proved to be inversely related to salinity (267) this is consistent with results reported in Section II,A. Methylmercuric ion forms in sediments upon addition of HgCl2, with a lag phase of 1 month (268). Biomethylation by lake water columns and by sediments coincided, apparently being related to overall microbial activity, and showed periodic fluctuations (269). Topping and Davies have demonstrated that mercury can be methylated in the water column of a sea loch (270). As has previously been noted, tin compounds can be methylated by sediments (121-124), and this is also true for lead (134-136, 271). The relative proportions of biotic and abiotic methylation processes for such systems still remain to be determined. 

This is an important parameter particularly for naturally occurring mixed cultures of organisms in the natural environment temperature may result in important changes in the composition of the microbial flora as well as on the rates for different processes. An illustrative example of its importance includes the following. An anaerobic sediment sample was incubated with... 

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