Peat soils

In contrast, composting processes utilize a mixture of solids and yard waste under controlled environmental conditions to produce a disinfected, humus-like product. Three common composting systems are a horizontal agitated reactor, a horizontal nonagitated reactor, and an aerated static pile system (nonproprietary). Compost can be marketed as a soil conditioner in competition with such products as peat, soil, and mulch. Although a large potential market exists, significant effort is required to penetrate this market. Yard waste revenue of 6.50/m (S5/yd ) and product revenue of 2.00/m ( 1.50/yd ) appear to be reasonable market values based on various studies reported on the Web. 

Torf-asche, /. peat ashes, -boden, m. peat soil, -eisenerz, n. bog iron ore. -erde, /. peaty soil, peat mold, -faser,/. peat fiber, -gas, n, peat gas. -geruch, m. peaty odor, -ge-schmack, m. peaty taste, fiavor of peat, torfhaltig, a. containing peat, peaty, torfig, a. peaty. 

Morris SA, S Radajewski, TW Willison, JC Murrell (2002) Identification of the functionally active methano-troph population in a peat soil microcosm by stable-isotope probing. Appl Environ Microbiol 68 1446-1453. 

Karlsson, T., Elgh-Dalgren, K., and Skyllberg, U., Modeling copper(II) complexation in a peat soil based on spectroscopic structural information, Soil Sci Soc Am J, 72 (5), 1286-1291, 2008. 

Aerts R, Toet S. Nutritional controls of carbon dioxide and methane emissions from Carex-dominated peat soils. Soil Biol. Biochem. 1997 29 1683-1690. 

For some trace elements (e.g., Zn and Cu), high organic matter leads to Zn/Cu deficiency. Zinc deficiency has been observed in muck or peat soils... 

Katase, T. (1981). The different forms in which p-coumaric acid exists in a peat soil. Soil Science 131 271-275. 

Katase, T. and Kondo, R. (1984). Distribution of different forms of some phenolic acids in peat soils in Hokkaido, Japan 1. Trans-4-hydroxycirmamic acid. Soil Science 138 220-225. 

Deitsch, J.J., Smith, J.A., Arnold, M.B., and Bolus, J. Sorption and desorption rates of carbon tetrachloride and 1,2-dichlorobenzene to three organobentonites and a natural peat soil, Environ. Sci. Technol, 32(20) 3169-3177, 1998. 

A methanotrophic biofilter is a biofilter in which methanotrophs are present. In a biofilter, a gas- or aqueous-phase contaminant stream is passed through a media on which the bacteria are growing. The media can be of several different materials, including compost, peat, soil material, or granular activated carbon. Specific strains of bacteria may be introduced into the filter and optimal conditions provided to preferentially degrade specific compounds. 

Chiou, C. T., D. E. Kile, D. W. Rutherford, G. Shung, and S. A. Boyd, Sorption of selected organic compounds from water to a peat soil and its humic-acid and humin fractions Potential sources of the sorption nonlinearity , Environ. Sci. Technol., 34,1254-1258 (2000). 

Histosois Bog or peat soils composed primarily of vegetative debris in various stages of decomposition. 

In previous studies, the solubilization of hydrophobic organic contaminants using surfactants has been shown to increase the rate of contaminant desorption from soil to water (Deitsch and Smith 1995 Yeom et al. 1995 Tiehm et al. 1997). A 3,000 mg/L solution of Triton X-100 (CMC = 140 mg/L) increased the rate of desorption of laboratory-contaminated TCE from a peat soil (Deitsch and Smith 1995). However, the solubilization effect was secondary compared to the surfactant s effect on the desorption rate coefficient. Yeom et al (1995) developed a model that satisfactorily predicted the extent of polycyclic aromatic hydrocarbon solubilization from a coal tar-contaminated soil. Only at high surfactant dosages did the model fail to accurately predict the ability of different surfactants to solubilize polycyclic aromatic hydrocarbons. It was hypothesized that mass-transfer limitations encountered by the polycyclic aromatic hydrocarbons in the soil caused the observed differences between the data and the model simulations. In another study (Tiehm et al. 1997), two nonionic surfactants, Arkopal N-300 and Saogenat T-300, increased the rate of polycyclic aromatic hydrocarbon desorption from a field-contaminated soil. The primary mechanism for the enhanced desorption of polycyclic aromatic hydrocarbons was attributed to surfactant solubilization of the polycyclic aromatic hydrocarbons. 

In the previous sections, the use of surfactants to increase the rate of desorption of hydrophobic organic contaminants was discussed. For the current study, several different surfactants were tested to determine whether the rate of TCE desorption from a peat soil could be increased. The effects of the surfactants on the rate of TCE desorption was tested using a continuous-flow stirred-tank reactor (CFSTR) methodology. The observed data were simulated using a distributed-rate kinetic desorption model. The parameters determined from the model simulation were then use to discern the effects of the surfactants on the rate of TCE desorption from the peat soil. The experimental methodology and the modeling procedure are now described in detail. 

In a previous study (Deitsch and Smith 1995), the influence of Triton X-100 on Kp for the same Picatinny peat soil was limited to Triton X-100 concentrations above 300 mg/1. At 300 mg/L and below, Triton X-100 did not affect the magnitude of Kp. Since this study has not included the effects of the surfactants on Kp, it will not be possible to identify the mechanism of increased TCE desorption for surfactant solutions that influence the magnitude of Kp. However, for the 30 and 300 mg/L concentrations of Triton X-100, Kp can be assumed to be constant. As a result, the influence of the 30 and 300 mg/L Triton X-100 concentrations on the distribution of rate coefficients can be discerned. 

Without knowing the effect of the surfactants on the distribution coefficient for TCE sorption to the peat soil, it is not possible to determine what mechanism caused the reduction in TCE removal. It is possible that the addition of sodiumdodecylsulfate, sodiumdodecylbenzenesulfonate, Tween 20, or Triton X-405 may have enhanced the sorption of TCE to the peat soil. If this were the case, the reduction in TCE removal would be attributable to a decrease in the magnitude of the concentration gradient driving the desorption process. Another possibility is that the addition of these surfactants may have inhibited the diffusion of the TCE from the peat soil to the aqueous phase. This last hypothesis could result if the surfactant... 

As described previously, Triton X-100 at concentrations of 30 mg/L and 300 mg/L should not affect the magnitude of TCE sorption to the peat soil. Therefore, for these two surfactant concentrations, the optimal distributions of rate coefficients can be compared to the distribution of rate coefficients from the water CFSTRs. The average distribution of rate coefficients for these Triton X-100 CFSTRs and the water CFSTRs are shown in Figure 9. 

Figure 3.7. Phenanthrene sorption isotherms on (A) the whole Amherst peat soil humic acid, (B) montmorillonite and a montmorillonite-humic acid complex (5 1 ratio), and (C) kaolin-ite and kaolinite-humic acid complex (5 1 ratio). Insets in parts B and C are the respective isotherms presented on a linear scale. Reprinted from Wang, K., and Xing, B. (2005). Structural and sorption characteristics of adsorbed humic acid on clay minerals. J. Environ. Qual. 34, 342-349, with permission from the Soil Science Society of America.

Meissner, R., and Leinweber, E (2004). PROWATER Prevention of diffuse water pollution with phosphorus from degraded and re-wetted peat soils—Final Report of an European Research Project, ed. UFZ Halle-Leipzig. 

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