title: Sulphur mineralization kinetics of cattle manure and green waste compost in soils.
abstract: Sulphur mineralization of cattle manure (CM) and green waste compost (GWC) added to six agricultural soils with different chemical properties was monitored over 10 weeks in a laboratory incubation experiment. Although the amount of sulphur was higher in CM than in GWC, the cumulative SO4(2-)-S values in GWC-treated soils were higher than in soil amended with CM. The percentages of mineralized S were always higher in GWC-treated soil (in the range 1.3-8.5%) than in CM-treated soil (in the range 0.9-3.8%). In three of the six soils, particularly for CM, an immobilization of sulphur was observed. Three kinetic models were evaluated for their suitability to describe the mineralization process. The first-order model best described S mineralization for both amended and control soils. The GWC substantially increased the amount of potentially mineralizable S (S0) relative to the controls. In GWC-treated soils, the rates of S mineralization (k) were higher than rates in the controls. The k of CM-amended soils was often lower than the k of control soils. Parameters derived from the model were tested as indices for assessing the relationships between S mineralization and soil characteristics. The S0 was positively correlated to the amount of cumulative SO4(2-)-S and also to the content of organic C, N and S in soil.
authors.affiliation: Department of Agricultural Chemistry and Biotechnology, University of Pisa, Pisa, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Saviozzi
authors.forename: Roberto
authors.initials: R
authors.lastname: Cardelli
authors.forename: Silvia
authors.initials: S
authors.lastname: Cipolli
authors.forename: Renato
authors.initials: R
authors.lastname: Levi-Minzi
authors.forename: Riccardo
authors.initials: R
authors.lastname: Riffaldi
mesh_terms: D000818:Animals; D002417:Cattle; D003247:Conservation of Natural Resources; D005308:Fertilizers; D007700:Kinetics; D008372:Manure; D012987:Soil; D013431:Sulfates / Q000032:analysis; D013455:Sulfur / Q000032:analysis*
chemical_list: D005308:Fertilizers; D008372:Manure; D012987:Soil; D013431:Sulfates; D013455:Sulfur