Estuarine sediments types

Ellis et al. (2003) obtained an Sse(iv)-se(o) range for Se(lV) reduction of 5.5%o to 5.7%o in three experiments with two of the three sediment slurries used for the Se(Vl) reduction experiments reviewed above. Se(lV) concentrations were 100 pmol/L and 240 nmol/L for the estuarine sediment experiments and 460 nmol/L for the wetland sediment. As with the Se(Vl) reduction experiments from this study, there was no apparent dependence on Se concentration or sediment type, though the number of experiments was small. 

Based on a full suite of sample types including soil, stream sediment, surface water, groundwater and offshore marine and estuarine sediment in the coastal zone. 

In addition to the analyses of lignin products by PGCMS as discussed here, one sample of estuarine sediment, comparable to sample S-15, was analyzed for lignin oxidation products by the CuO oxidation method (22). The distribution of various types of phenolic compounds In the sediment Is compared to that of Spartlna... 

TBT, being an organotin compound, is of particular importance for sediment samples, as this species is the main component in anti-fouling paints for boats, and thus can be found in substantial amounts in harbour and estuarine sediments. Organotin compounds also accumulate in mussels, and organotin speciation can be carried out using similar methods for both types of samples. ... 

Several factors influence the formation of CH3Hg, including temperature, mercuiy and bacteria concentrations, pH, type of soil, type of sediment, the sulphide concentration, and, of course, redox conditions. Seasonal variations in methylation in estuarine sediments, relate to bacterial activity, which may also apply to organic sediments, compared to sandy sediments. 

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