Sulphur speciation and biogeochemical cycling in long-term arable cropping of subtropical soils: evidence fromwet-chemical reduction and SK-edge XANES spectroscopy

D. SOLOMON, J . LEHMANN, I . LOBE, C. E. MARTINEZ, S. TVEITNES, C. C. DU PREEZ & W. AMELUNG Department of Crop and Soil Sciences, Cornell University, Bradfield and Emerson Hall, Ithaca, NY 14853, USA, Berlin University of Technology, Institute of Ecology, Department of Soil Science, Salzufer 12, 10587 Berlin, Germany, Department of Crop and Soil Sciences, 418 ASI Building, The Pennsylvania State University, University Park, PA 16802, USA, Department of Soil and Water Sciences, Agricultural University of Norway, PO Box 5028, 1432 Ås, Norway, and Department of Soil, Crop and Climate Sciences, University of the Free State, PO Box 339, Bloemfontein 9300, Republic of South Africa