EDTA-extractable copper, zinc, and manganese in soils of the canterbury plains

Abstract

A large number of topsoil and subsoil samples from the Canterbury Plains were analysed for EDT A-extractable copper, zinc, and manganese. The data obtained for all 3 elements were found to be lognormally distributed. Marked differences were apparent in the mean extractable copper and zinc contents of different soil series. Younger soils contained greater amounts of extractable copper and zinc than more strongly developed soils — this trend was not apparent for manganese. Overall correlations between extractable soil copper and zinc levels, and the concentrations of these elements in lucerne grown at the sampling sites were poor. However, highly significant correlations were obtained between the mean extractable copper and zinc levels for individual soil series and the mean copper and zinc concentrations of lucerne growing on the same series. In general, the levels of extractable copper and zinc in the soils on the Canterbury Plains are very low, and many soils should be regarded as potentially copper and zinc deficient. Manganese levels appear to be adequate. Information on trace element levels in soil series could be a useful aid in predicting the probability of trace element deficiencies. © 1984 Taylor & Francis Group, LLC.