Organic sulfur forms in mineral top soils of the Marsh in Schleswig-Holstein, Northern Germany

Little is known about the nature of, organic sulfur (S) in soils of the Marsh in Schleswig-Holstein, Northern Germany. In addition to total and inorganic S, we determined two organic S fractions, (ester sulfate-sulfur and carbon-bonded sulfur) in 14 aerated. mineral top horizons of two salt marshes and ten dyked polder soils of different age. All soils, developed from marine sediments. Total S concentrations ranged from 153 to 950 mg kg(-1). Organic S was the main S constituent (range from 53 to 99% with a median of 97%). Higher inorganic S levels were found Only in the salt marshes due to soluble sulfate (15 to 47%). The younger marsh soils (salt marshes and soils of a polder dyked in 1978) had unique high S, contents of 0.9 to 2.4% in their, organic matter, whereas the S contents of the organic matter in older marsh soils were at only 0.6%, This S-rich organic matter is a heritage of a former anoxic marine environment. In most horizons the carbon-bonded S was the dominant sulfur form. However, both carbon-bonded S and ester sulfate-S did not relate to soil age. This limits the benefit of the wet chemical fractionation procedure used,for,studying the fate of organic S in marsh soils.