Keywords: Sulfur fertilizers, Fertilizer recommendations.
The last quarter of the 20th Century has seen the introduction of significant legislation in Europe designed to reduce the extent and quantity of atmospheric pollution. A major result of this has been the decline in the burning of sulfur-containing fossil fuels, particularly coal, and the introduction of sulfur recovery systems to flue stacks.
In addition to this there has been a major change at the same time in the composition of fertilizers. The current use of ammonium nitrate, urea, ammonium phosphates and triple superphosphate has resulted in very low adventitious sulfur inclusion compared with less concentrated historical fertilizers which often contained ammonium sulfate and single superphosphate.
The reduction in anthropogenic emissions of sulfur and the replacement of sulfur-containing fertilizer raw materials has led to a situation in which for the first time since the initial development of the fertilizer industry, at least in the industrialised countries of Europe and their near neighbours, deficiencies of sulfur have appeared in many agricultural crops.
The paper attempts to examine the various current recommendations for the use of sulfur-providing fertilizers from seventeen different European countries, at a time when the use of fertilizer sulfur is still developing.
It is concluded that there are some similarities but also wide differences in the advice being offered in the various countries, which is only in part explained by differences in sulfur deposition, soil types, potentials for leaching losses and crop demand.
Dr Kerr Walker, Scottish Agricultural College, Bucksburn, Aberdeen, Scotland.
Chris J Dawson, International Fertilizer Society, PO Box 4, York, UK.
20 Pages, 17 Tables.
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