Sulphur and phosphorus in some Eastern Australian soils

Abstract

One hundred and fifty-five soils of differing soil types and collected from a wide range of parent materials, climatic conditions, and topography were examined for carbon, nitrogen, sulphur, and phosphorus. A close relationship between carbon, nitrogen, and non-sulphate sulphur was found, although alkaline soils contained a slightly higher relative proportion of non-sulphate sulphur than did acid soils. Water-soluble sulphate comprised only a small proportion of the total sulphur in the majority of the soils. Organic phosphorus, although correlated with carbon and nitrogen, showed much wider variation than did sulphur, and it seemed likely that part at least of the organic phosphorus was not closely associated with the carbon, nitrogen, and sulphur in the soil organic matter. The mean relative proportions of carbon, nitrogen, non-sulphate sulphur, and organic phosphorus were 150: 10: 1.26: 0.66.