Soils chemical speciation

Gamble, D.S. and S.U. Khan (1990). Atrazine in organic soil Chemical speciation during heterogeneous catalysis. J. Agric. Food Chem., 38 297-308. 

Gamble, D.S. and S.U. Khan (1988). Atrazine hydrolysis in aqueous suspensions of humic acid at 25°C. Can. J. Chem., 66 2605-2617. Gamble, D.S. and S.U. Khan (1990). Atrazine in organic soil Chemical speciation during heterogeneous catalysis. J. Agric. Food Chem., 38 297-308. 

Preventive Measures. The intake uptake biokinetic model (lUBK) projects the impact of lead in the environment on blood lead. This model assumes conservatively high levels of intake and cannot account for chemical speciation, thus over-predictions of blood lead levels often occur. Nonetheless, because of the allegations of the impact of blood lead and neurobehavioral development, blood lead levels in children are being reduced adrninistratively to below 10 //g/dL. In order to do so, soil leads are being reduced to a level of between 500—1000 ppm where remediation is required. 

A method for estimating the TSCF for equation 14.24 is given in Table 14.10. The root concentration factor is also defined in Table 14.10 as the ratio of the contaminant in the roots to the concentration dissolved in the soil water (pg/kg root per pg/L). This is important in estimating the mass of contaminant sorbed to roots in phytoremediation systems. The values of TSCF and RCF for metals depend on the metals redox states and chemical speciation in soil and groundwater. 

This paper discusses (1) soil and groundwater and (2) aquatic equilibrium and ranking models. The second category deals with the chemical speciation in soil and groundwater, and with the environmental rating of waste sites, in cases where detailed modeling is not desirable. 

Nolan A.L., McLaughlin M. J., Mason S.D. Chemical speciation of Zn, Cd, Cu and Pb in pore waters of agricultural and contaminated soils using donnan dialysis. Environ Sci... 

The term bioavailability has different meanings in different contexts and disciplines. Numerous definitions of bioavailability exist. Research on the relationship between bioavailability and chemical speciation (forms) originated in the field of soil fertility in the search for a good predictor for the bioavailability of essential plant nutrients (Traina and Laperche 1999). It is well accepted that dissolved nutrients are more labile and bioavailable to plants than solid-phase forms (including sorbed species). The same has been considered to be true for organic contaminants and their availability for microbial degradation. 

Parker, D.R., W. A. Norvell and R. L. Chaney, 1995, GEOCHEM-PC, a chemical speciation program for IBM and compatible personal computers. In R. H. Loep-pert, A. P. Schwab and S. Goldberg (eds.), Chemical Equilibrium and Reaction Models. Soil Science Society of America Special Publication 42,253-269. 

Sauve, S., Dumestre, A., McBride, M. and Hendershot, W. (1998). Derivation of soil quality criteria using predicted chemical speciation of Pb2+ and Cu2+, Environ. Toxicol. Chem., 17, 1481-1489. 

Ure AM, Davidson CM. Chemical speciation in soils and related materials by selective chemical extraction. In Ure AM, Davidson CM (eds.), Chemical Speciation in the Environment, 2nd ed. Malden, MA Wiley-Blackwell Science, Inc. 2002, pp. 265-299. 

Keywords Solid-phase Al, soils, mobility, chemical speciation, selective extractions, Alpsioi. Alr Alpy Alox- AIdcb. fCpy, Feox, Fcdcb... 

An earlier study on the speciation of heavy metals and geochemical mapping of the total metal content of the surface soils of Delhi7 showed the total Al content to vary between 1.87 to 5.34% with a mean of 3.57%. In view of the above, the objective of this research was to ascertain primarily the status of Aluminum in Delhi soils by studying its chemical speciation in the soil profile in order to improve the understanding of its distribution in the solid-phase pool of the soil. More precisely, the objectives were ... 

To study the chemical speciation of Aluminum in the solid - phase of the selected soil samples by selective chemical extraction procedures,... 

The major part of the biosphere is aerobic and consequently priority has been given to the study and assessment of biodegradability under aerobic conditions. Nevertheless, there are environmental compartments that can be permanently (e.g. anaerobic digesters) or temporarily anaerobic (e.g. river sediments and soils) and surfactants do reach these. The majority of surfactants entering the environment is exposed to and degraded under aerobic conditions. This is the predominant mechanism of removal even in cases of absence of wastewater treatment practices (direct discharge) and it is estimated that less than 20% of the total surfactant mass will potentially reach anaerobic environmental compartments [1]. Only in a few cases, however, will the presence of surfactants in these compartments be permanent. The presence of surfactants in anaerobic zones is not exclusively due to the lack of anaerobic degradation. Physico-chemical factors such as adsorption or precipitation play an important role as well as the poor bioavailability of surfactant derivatives (chemical speciation) in these situations. 

Sauve S, Parker DR (2000) Chemical speciation of trace elements in soil solution. In Tabatabai MA and Sparks DL (eds) Chemical processes in soils. Soil Sci Soc Am Book Series no 8, Madison, Wisconsin... 

Bertsch, P. M., Hunter, D. B., Sutton, S. R., Bajt, S. Rivers, M. L. 1994. In situ chemical speciation of uranium in soils and sediments by micro x-ray absorption spectroscopy. Environmental Science and Technology, 28, 980-984. 

Nico, P.S., Ruby, M.V., Lowney, Y.W. and Holm, S.E. (2006) Chemical speciation and bioaccessibility of arsenic and chromium in chromated copper arsenate-treated wood and soils. Environmental Science and Technology, 40(1), 402-8. 

Schulton and Sorge [274] used laser Raman spectroscopy to provide detailed information on the location, elemental composition and chemical speciation of organic compounds in soil. 

Part II considers speciation in specific compartments of the environment viz. the atmosphere, biological systems, soils, sediments and natural waters, and with particular aspects of the speciation of environmentally important radionuclides. Two new chapters have been added to make the coverage even more comprehensive. These new chapters are Chapter 10, Chemical Speciation in Soib and Related Materials by Selective Chemical Extraction by the editors, and Chapter 12, Speciation in Seawater by R.H. Byrne of the University of South Florida. 

Sposito, G. and Coves, J. (1988) SOILCHEM A Computer Program for the Calculation of Chemical Speciation in Soils. The Kearny Foundation of Soil Science, University of California, CA. 

In this chapter, we shall introduce soil speciation concepts by consideration of inorganic trace elements in dissolved and adsorbed forms, with reference to both their molecular speciation and their operationally defined soil component speciation. We shall then consider the implications of chemical speciation in soils for agriculture and soil pollution. 

Chemical speciation in soils and related materials by selective chemical extraction... 

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