HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Skyllberg, U. Articles by Bleam, W. F. Search for Related Content PubMed Articles by Skyllberg, U. Articles by Bleam, W. F. Agricola Articles by Skyllberg, U. Articles by Bleam, W. F.

Binding of Mercury(II) to Reduced Sulfur in Soil Organic Matter along Upland-Peat Soil Transects

Dep. of Soil, Water and Climate, Univ. of Minnesota, 1991 Upper Buford Circle, St. Paul, MN 55108;
Dep. of Agronomy, Kansas State Univ.;
Soil Science Dep., Univ. of Wisconsin, Madison WI 53706.

^* Corresponding author (ulf.skyllberg{at}sek.slu.se).

ABSTRACT

The binding of Hg²⁺ in organic matter of soils and waters controls the transport and transformations of Hg in terrestrial and aquatic ecosystems. We developed a competitive complexation method using the strong complexation of Hg²⁺ by Br^– for determining the Hg²⁺ binding strength in organic soils at native and elevated Hg concentrations. The distribution coefficients determined in KBr suspensions for sorption of native Hg²⁺ to soil organic carbon (SOC) (K_SOC) are in the range of 10²² to 10²³. The K_SOC significantly decreased with increased additions of Hg²⁺ and with decreasing pH. Using data for reduced organic S concentrations determined by x-ray absorption near-edge structure spectroscopy (XANES), we calculated surface complex formation constants on the order of 10³² for a model site having acidity constants of mercaptoacetic acid. This value is in fair agreement with the tabulated value of 10³⁴⁵ for Hg²⁺ binding in mercaptoacetic acid. At native Hg concentrations, formation constants and K_SOC values were similar for different types of soil organic matter along transects from uplands into wetlands, despite varying concentrations of Hg and reduced organic S. Our adsorption data are consistent with the conclusions from our previous extended x-ray absorption fine structure spectroscopy (EXAFS) study that in a humic acid and soil, Hg²⁺ ions bond in two-fold coordination involving one reduced S and one O or N.

U. Skyllberg present address: Dep. of Forest Ecology, Swedish Univ. of Agricultural Sciences, S-901 83 Umeå, Sweden.

Received for publication April 13, 1999.

This article has been cited by other articles:

				S. D. Siciliano, A. Sangster, C. J. Daughney, L. Loseto, J. J. Germida, A. N. Rencz, N. J. O'Driscoll, and D. R. S. Lean Are Methylmercury Concentrations in the Wetlands of Kejimkujik National Park, Nova Scotia, Canada, Dependent on Geology? J. Environ. Qual., November 1, 2003; 32(6): 2085 - 2094. [Abstract] [Full Text] [PDF]

				M. Cruz-Guzman, R. Celis, M. C. Hermosin, P. Leone, M. Negre, and J. Cornejo Sorption-Desorption of Lead (II) and Mercury (II) by Model Associations of Soil Colloids Soil Sci. Soc. Am. J., September 1, 2003; 67(5): 1378 - 1387. [Abstract] [Full Text] [PDF]

				D. F. Grigal Mercury Sequestration in Forests and Peatlands: A Review J. Environ. Qual., March 1, 2003; 32(2): 393 - 405. [Abstract] [Full Text] [PDF]