Some factors affecting the extraction of sulphate from selected Lower Fraser Valley and Vancouver Island soils

A study was undertaken to determine some of the factors which affected the extraction of sulphur from seven selected soils of the Lower Fraser Valley and Vancouver Island; with particular reference to the effect of pH concentration and cation of phosphate buffers. In all cases the presence of phosphate resulted in more sulphur being extracted, than extraction with water only. In every instance increasing the concentration of neutral sodium phosphate buffers from 0.005M to 0.5M resulted in increasing sulphur extraction. Using a 0.5M sodium phosphate buffer and increasing the pH from 4 to 8 generally resulted in maximum extraction at pH 7, except notably in the Langford soil in which the amount of sulphur extracted increased as the pH was changed from 4 to 8. The behaviour of four surface soils when extracted with 0.5M sodium phosphate at varying pH levels was quite similar, the mineralogy of the