EFFECTS OF ADDITION OF COPPER, MANGANESE, ZINC AND CHROMIUM COMPOUNDS ON AMMONIFICATION AND NITRIFICATION DURING INCUBATION OF SOIL BY P. R. PREMI and A. H. CORNFIELD

Most of the work which has been done on trace elements in soils has been in relation to deficiency or toxicity effects on plants. Although a certain amount of work has been reported on the effects of trace elements on ammonification and nitrification in soils 12 a 4 5 6 the results obtained are conflicting. Trace elements may be introduced into soil where pesticide sprays e.g. copper fungicides are used, or by application of sewage materials or town composts. In addition some soils may be fairly high in one or more trace elements due to the geology of the soil or through the application of mining wastes. In these ways the trace elements in soils may be increased to such an extent as to be toxic to plant growth and soil microbiological processes. This paper reports on the effects of adding copper, manganese, zinc and chromium as sulphates and copper and zinc as carbonates on ammonification and nitrification on subsequent incubation of soil.