Fe, Al, Mn, and S chemistry of Sphagnum peat in four peatlands with different metal and sulfur input.
Comparisons among 4 peatland sites representing a gradient of increasing Fe, Al, Mn, and S loading revealed significant accumulation of total Fe, Al, and S, but not Mn, in surface (0 to 20 cm deep) peat along the gradient. Iron and Al accumulation were contributed mainly by organically bound fractions, with oxides contributing to a lesser extent. Although SO4 2- and Fe sulfides showed significant increases in concentration along the gradient, most of the accumulation of total S was contributed by organic, rather than inorganic S. Laboratory studies of Fe2+ adsorption by peat indicated that increasing the pH of added Fe2+ solutions (pH values of 3, 4, 5, and 6) did not significantly affect Langmuir equation estimates of either maximum Fe2+ adsorption capacity or the affinity of peat for Fe2+. Regardless of the pH of the added Fe2+ solutions, final solution pH values were relatively uniform, averaging about 3.4, reflecting a considerable bufferring capacity of Sphagnum peat. Factors affecting the accumulation of metals and S in peat remain topics for further investigation
|Main Author:||Wieder, R Kelman.|
|Other Authors:||Lang, Gerald.|