ISSN:
1573-5036
Keywords:
organic sulphur
;
soil testing
;
sulphate
;
wheat
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Ten soils collected from the major arable areas in Britain were used to assess the availability of soil sulphur (S) to spring wheat in a pot experiment. Soils were extracted with various reagents and the extractable inorganic SO4-S and total soluble S(SO4-S plus a fraction of organic S) were determined using ion chromatography (IC) or inductively-coupled plasma atomic emission spectrometry (ICP-AES), respectively. Water, 0.016 M KH2PO4, 0.01 M CaCl2 and 0.01 M Ca(H2PO4)2 extracted similar amounts of SO4-S, as measured by IC, which were consistently smaller than the total extractable S as measured by ICP-AES. The amounts of organic S extracted varied widely between different extractants, with 0.5 M NaHCO3 (pH 8.5) giving the largest amounts and 0.01 M CaCl2 the least. Organic S accounted for approximately 30–60% of total S extracted with 0.016 M KH2PO4 and the organic C:S ratios in this extract varied typically between 50 and 70. The concentrations of this S fraction decreased in all soils without added S after two months growth of spring wheat, indicating a release of organic S through mineralisation. All methods tested except 0.5 M NaHCO3-ICP-AES produced satisfactory results in the regression with plant dry matter response and S uptake in the pot experiment. In general, 0.016 M KH2PO4 appeared to be the best extractant and this extraction followed by ICP-AES determination was considered to be a good method to standardise on.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00010076
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