Sulfur speciation in some Chesapeake Bay tidal marsh soils

Haering, K.C.; Rabenhorst, M.C.; Fanning, D.S.

Sulfur speciation in some Chesapeake Bay tidal marsh soils

1989

Haering, K.C. | Rabenhorst, M.C. | Fanning, D.S.

In order to study S compounds and processes in Chesapeake Bay marshes, Sulfihemist profiles were sampled along a transect from inland to streamside marsh areas of Cedar Creek Marsh and in seven marshes along the Nanticoke River in Dorchester County, MD. In both areas, higher concentrations of pyrite were found in areas that received Fe inputs from tidal overwash or from diffusion from mineral layers within the profile. Pyrite accumulation was favored in streamside profiles that were subjected to frequent tidal flushing. Pyrite was the major form of S in most of the organic horizons of the Cedar Creek streamside pedons and in several of the Nanticoke pedons. Organic S was the major form of S in the Cedar Creek inland pedons. In both study areas, organic C was correlated with total S, apparently because of the S associated with organic materials and the ability of organic matter to hold sulfate-containing tidal water. High total S values were found to be indicators of areas of organic S accumulation. Pyrite content was not significantly correlated with total S or organic C. Identification of "sulfidic materials" for purposes of soil classification should be based on analysis of pyrite S, as total S may be a poor estimate of oxidizable sulfides.

اظهر المزيد [+]