Soluble Organic Matter

B. Inorganic seawater plus soluble organic matter (2.3 mg C/L) ... 

There are two main aims in applications of PTLC in organic geochemistry (1) assessment of the bulk group composition of soluble organic matter by its fractionation and (2) separation of a particular selected group of compounds with geochemical meaning. The important factor in technique selection should be the repeatability of... 

Column Chromatography in Soluble Organic Matter Fractionation... 

Radke et al. [28] described an automated medium-pressure liquid chromatograph, now commonly called the Kohnen-Willsch instrument. At present, the method is widely used to isolate different fractions of soluble organic matter (for instance, as described in Reference 29 to Reference 31). A combination of normal phase and reversed-phase liquid chromatography has been used by Garrigues et al. [32] to discriminate between different aromatic ring systems and degrees of methylamine in order to characterize thermal maturity of organic matter. 

Another variation of the preceding method is to apply HPLC to fractionate the cleaned-up aliphatic-aromatic fraction from flash colurim separation of soluble organic matter as it is performed in the Chevron laboratory, for example, as described in Reference 2. A Waters HPLC system equipped with a preparative Whatman Partisil 10 silica column (9.4 X 500 mm), a HPLC pump, and two detectors for separation monitoring (a UV and refractive index detector) are used, giving three fractions of aliphatic hydrocarbons, mono-, di-, and triaromatics and polar compounds. The hrst two fractions are eluted with hexane, whereas polar compounds are eluted with... 

FIGURE 15.1 Scheme showing PLC group fractionation of soluble organic matter into fractions of aliphatic hydrocarbons, aromatic compounds with application of urea clathra-tion, and methylation of carboxylic acids in polar fractions based on experimental data given in Reference 36 to Reference 52, Reference 77 to Reference 81, and Reference 88 to Reference 89. 

FIGURE 15.2 Group fractionation of soluble organic matter with application of argentation PLC based on Reference 61 and Reference 89 to Reference 93. 

FIGURE 15.3 PLC separation of carboxylic acids from soluble organic matter with the use of carboxylic acids esterification based on experimental data given in Reference 36, Reference 67 to Reference 69, and Reference 102 to Reference 104. 

The detailed information concerning geochemical factors, which influence the group composition of soluble organic matter, can be found in numerous general geochemical publications [e.g., 2,114—117]. The most important factors are described briefly in the following subsections. 

FIGURE 15.7 Secondary changes in the total group composition of soluble organic matter as a result of simulated water washing extracts of the Miocene lignite and shale (both of the Bechatow open cast mine, Poland), the Upper Devonian shale (the Holy Cross Mountains, Poland), and the Upper Carboniferous bituminous coal (the Upper Silesia Coal Basin, Poland). 

Dissolved organic matter can be thought of, for simplicity, as soluble organic matter present in soil solution. However, although some workers have measured dissolved organic matter in soil leachates or extracted soil solutions, many use the extract from a 1 2 w/v soil/water extraction... 

As with particulate and soluble organic matter, seasonal fluctuations in potentially mineralizable C and N can occur in field soils (Boone 1994 Bonde and Rosswall 1987 Campbell et al.1999 a,b). These are normally related to seasonal inputs of readily mineralizable organic matter through rhizodeposition of root material during crop growth and/or inputs of litter and crop residues. 

Soluble organic matter About 0.05-0.40% organic C and total N Water soluble organic compounds present in soil solution including simple compounds of plant and microbial origin. 

Hernandez D, Fernandez JM, Plaza C, Polo A (2007) Water-soluble organic matter and biological activity of a degraded soil amended with pig slurry. Sci Total Environ 378 101-103... 

The (aerobic) biodegradability of the organic matter in wastewater affects the anaerobic formation rate of Ss. The results shown in Figure 7.14 correspond to the findings that a soluble COD value, CODs, below 50 gCOD m-3 has no real potential for sulfide formation (cf. Section 6.2.4), as this value typically corresponds to non- and slowly biodegradable, soluble organic matter. 

Chen Y, Katan J, Gamliel A, Aviad T, Schnitzer M (2000) Involvement of soluble organic matter in increased plant growth in solarized soils. Biol Fert Soils 32 28-34. doi 10.1007/ S003740000209... 

Mercury has several other characteristics that make it of particular environmental concern and make it likely to be found as many different species. It is a natural constituent of soil, although it occurs at low concentrations. It is widely used both in industry and in the laboratory, making it a common contaminant of reference soils. Metallic mercury has a relatively high vapor pressure, which means that it can occur in measurable amounts in the soil atmosphere. It has a high affinity for reduced sulfur compounds in soil solids and soluble organic matter that allows species to be present in the soil solution above mercury s solubility limit. 

Prior work has been concentrated mostly on the isolation of distinct NSO compound classes from soluble organic matter. Often, selective extraction methods are applied as described for the isolation of, for example, phenols, [39,40] fatty acids [41] and basic nitrogen compounds such benzoquinolines... 

Table 16.1 Characteristics of the investigated soils and parameters affecting redox of chromium TOC total organic carbon, SOM soluble organic matter. Reprinted with permission from Kozuh N, Stupar 1, Gorenc B (2000) Reduction and oxidation processes of chromium in soils. Environ Sci Technol 34 112-119. Copyright 2000 American Chemical Society...

Teranishi, K., K. Hamada, and H. Watanabe, Mutagenicity in Salmonella typhimurium Mutants of the Benzene-Soluble Organic Matter Derived from Airborne Particulate Matter and Its Five Fractions, Mutat. Res., 56, 273-280 (1978). 

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