Influence organic carbon

Canfield, D.E. (1994) Factors influencing organic carbon preservation in marine sediments. Chem. Geol. 114, 315-329. 

Davis C., Pratt L. M., Sliter W. V., Mompart L., and Murat B. (1999) Eactors influencing organic carbon and trace metal accumulation in the Upper Cretaceous La Luna Eormation of the western Maracaibo Basin, Venezuela. In Evolution of the Cretaceous Ocean-Climate System. Geological Society of America Special Paper 332 (eds. E. Barrera and C. Johnson). Geological Society of America, Boulder, pp. 203 -230. 

Arthur, M.A. Sageman, B.B. Marine black shales a review of depositional mechanisms and significance of ancient deposits. Annual Review of Earth Planetary Science 22,499-551. Canfield, D.E. (1994) Factors influencing organic carbon preservation in marine sediments. Chemical Geology, 1994,114, 315-329. 

Chemical composition data for CPM and FPM for a variety of locations are summarized in Table 5. These data illustrate several important points. First, the distributions of the PM q between CPM and FPM vary from about 0.4 to 0.7. Second, the ratio of PM q to TSP varies from 0.58 to 0.79. In general, both this ratio and the ratio of FPM to PM q tend to be higher at mral sites, but Bermuda, because of the large influence of sea salt in the CPM, is an exception. Sulfate (SO ), carbon (as organic carbon, OC, and elemental carbon, EC), and nitrate (NO3 ) compounds generally account for 70—80% of the FPM. In the eastern United States, compounds are the dominant species, although very Httie is emitted directiy into the atmosphere. Thus... 

Research into the aquatic chemistry of plutonium has produced information showing how this radioelement is mobilized and transported in the environment. Field studies revealed that the sorption of plutonium onto sediments is an equilibrium process which influences the concentration in natural waters. This equilibrium process is modified by the oxidation state of the soluble plutonium and by the presence of dissolved organic carbon (DOC). Higher concentrations of fallout plutonium in natural waters are associated with higher DOC. Laboratory experiments confirm the correlation. In waters low in DOC oxidized plutonium, Pu(V), is the dominant oxidation state while reduced plutonium, Pu(III+IV), is more prevalent where high concentrations of DOC exist. Laboratory and field experiments have provided some information on the possible chemical processes which lead to changes in the oxidation state of plutonium and to its complexation by natural ligands. 

Houser JN, Bade DL, Cole JJ, Pace ML (2003) The dual influences of dissolved organic carbon on hypolimnetic metabolism organic substrate and photosynthetic reduction. Biogeochemistry 64 247-69... 

Rates of hydrolysis may be influenced by the presence of dissolved organic carbon, or organic components of soil and sediment. The magnitude of the effect is determined by the structure of the compound and by the kinetics of its association with these components. For example, whereas the neutral hydrolysis of chlorpyrifos was unaffected by sorption to sediments, the rate of alkaline hydrolysis was considerably slower (Macalady and Wolf 1985) humic acid also reduced the rate of alkaline hydrolysis of 1-octyl 2,4-dichlo-rophenoxyacetate (Perdue and Wolfe 1982). Conversely, sediment sorption had no effect on the neutral hydrolysis of 4-chlorostilbene oxide, although the rate below pH 5 where acid hydrolysis dominates was reduced (Metwally and Wolfe 1990). 

Torrents A, BG Anderson, S Bilboulian, WE Johnson, CJ Hapeman (1997) Atrazine photolysis mechanistic investigations of direct and nitrate-mediated hydroxyl radical processes and the influence of dissolved organic carbon from the Chesapeake Bay. Environ Sci Technol 31 1476-1482. 

Miskimmin BM, Rudd JWM, Kelly CA. 1992. Influence of dissolved organic carbon, pH, and microbial respiration rates on mercury methylation and demethylation in lake water. Can J Fish Aquat Sci 49 17-22. 

J, K. Martin, Factors influencing the loss of organic carbon from wheat roots. Soil Biol. Biochem. 9 1 (1977). 

The vacuum extraction method has been effectively applied to removing VOCs with low organic carbon content from well-drained soil, although it may also be effective for finer and wetter soils, but with comparatively slower removal rates. There are generally significant differences in the air permeability of various strata, which can influence process performance. Contaminants with low vapor pressure or high water solubilities are difficult to remove. 

The conclusions of Hurt s study of year-by-year oxygen isotope ratios in 72 years of S. gigantea are thus supportive of the conclusions of the CIAP study [49] that solar variations influence the abundances of many kinds of chemical species in the stratosphere, and therefore influence the.amount of solar energy they absorb and re-radiate to earth, and therefore influence the surface temperature of the earth and especially the surface temperatures of the oceans. It is the surface temperature of the oceans which produces the phenomena we have discussed the isotope ratio variations in rain and hence in tree rings, the isotope ratio variations in the Greenland ice cap, in the organic carbon and uranium concentrations in sea cores, and furthermore variations of the sea surface temperature produces variations in the carbon-14 to carbon-12 ratio fractionation at the sea air interface and hence in the carbon-14 content of atmospheric carbon dioxide and hence in the carbon-14 content of tree rings. 

Hapeman, C J., S. Bilboulian, B.G. Anderson, and A. Torrents. 1998. Structural influences of low-molecular weight dissolved organic carbon mimics on the photolytic fate of atrazine. Environ. Toxicol. Chem. 17 975-981. 

VandenBygaart AJ, Gregorich EG, Angers DA (2003) Influence of agricultural management on soil organic carbon a compendium and assessment of Canadian studies. Can J Soil Sci 83 363-380... 

Holten Liitzhoft, H.-C., Yaes, W. H. J., Freidig, A. P., Halling-Sorensen, B. and Hermens, J. L. M. (2000). 1-Octanol/water distribution coefficient of oxolinic acid influence of pH and its relation to the interaction with dissolved organic carbon, Chemosphere, 40, 711-714. 

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