TY - JOUR
T1 - Method for the partitioning of organic sulphur in forest soil O layers
AU - Strehl, C.
AU - Prietzel, J.
N1 - Funding Information:
We gratefully acknowledge the funding of our work by the Federal State of Baden-Württemberg (Forschungszentrum Karlsruhe, Projekt Europäisches Forschungszentrum für Maßnahmen zur Luftreinhaltung) and the excellent technical assistance of Mrs. K. Kellersmann.
PY - 1998/11
Y1 - 1998/11
N2 - A new method for the partitioning of total sulphur and organic S species (C-bonded S, ester sulphate S) in different humus fractions of forest soil O layers is presented and discussed. Our method combines an adopted version of the sequential humus fractionation procedure of Schnitzer and Schuppli (1989; Soil Science Society of America Journal 53, 1418-1424) with wet-chemical procedures for analysis of C(org), S(tot), and hydriodic acid (HI)-reducible S in soils. The procedures were modified for the determination of micro-amounts of these compounds in aqueous and non-aqueous solvents. The applicability of our method was tested with samples taken from of and Oh layers of two acidic forest soils and compared with results of a traditional humic acid:fulvic acid:humin fractionation. The average recoveries of C(org) and S(tot) for the proposed fractionation method were 91% (C(org)) and 100% (S(tot)), compared to 96% (C(org)) and 87% (S(tot) for the traditional procedure. Average HI-reducible S recoveries of > 110% in both methods suggest a conversion of C-bonded S during the sequential extraction into ester sulphate or SO4/2-S. On average, polycondensed humins accounted for 70% of the organic matter of the O layers from acid forest soils. The percentage of hydrophilic compounds soluble in alkaline extractants was 18%, that of hydrophobic substances extractable with solvents of low polarity 12%. About 37% of the forest floor S pool were bound in ecologically labile hydrophilic humus compounds, indicating a considerable S enrichment of the latter fraction. Contrarily, hydrophobic organic matter extractable with solvents of low polarity was depleted in total S and particularly in HI-reducible S.
AB - A new method for the partitioning of total sulphur and organic S species (C-bonded S, ester sulphate S) in different humus fractions of forest soil O layers is presented and discussed. Our method combines an adopted version of the sequential humus fractionation procedure of Schnitzer and Schuppli (1989; Soil Science Society of America Journal 53, 1418-1424) with wet-chemical procedures for analysis of C(org), S(tot), and hydriodic acid (HI)-reducible S in soils. The procedures were modified for the determination of micro-amounts of these compounds in aqueous and non-aqueous solvents. The applicability of our method was tested with samples taken from of and Oh layers of two acidic forest soils and compared with results of a traditional humic acid:fulvic acid:humin fractionation. The average recoveries of C(org) and S(tot) for the proposed fractionation method were 91% (C(org)) and 100% (S(tot)), compared to 96% (C(org)) and 87% (S(tot) for the traditional procedure. Average HI-reducible S recoveries of > 110% in both methods suggest a conversion of C-bonded S during the sequential extraction into ester sulphate or SO4/2-S. On average, polycondensed humins accounted for 70% of the organic matter of the O layers from acid forest soils. The percentage of hydrophilic compounds soluble in alkaline extractants was 18%, that of hydrophobic substances extractable with solvents of low polarity 12%. About 37% of the forest floor S pool were bound in ecologically labile hydrophilic humus compounds, indicating a considerable S enrichment of the latter fraction. Contrarily, hydrophobic organic matter extractable with solvents of low polarity was depleted in total S and particularly in HI-reducible S.
UR - http://www.scopus.com/inward/record.url?scp=0032214006&partnerID=8YFLogxK
U2 - 10.1016/S0038-0717(98)00024-8
DO - 10.1016/S0038-0717(98)00024-8
M3 - Article
AN - SCOPUS:0032214006
SN - 0038-0717
VL - 30
SP - 1725
EP - 1731
JO - Soil Biology and Biochemistry
JF - Soil Biology and Biochemistry
IS - 13
ER -