Sager


Die Bodenkultur - Journal for Land Management, Food and Environment

M. Sager:

Possible trace metal load from fertilizers

Summary

The annual load of various trace elements (As, Cd, Co, Cr, Ni, Pb) deriving from the application of mineral fertilizers to arable soils, has been calculated. As a data base, averaged trace element contents of fertilizers, sampled due to state control of fertilizers within the period 1986-94, as well as the amount of mineral fertilizers sold in Austria in the cropping season 1992/93, are compiled. The phosphate component supplies significantly higher trace element loads than the nitrogen components. The well-known correlation between nominal phosphorus contents and cadmium contents found, is reconfirmed. In comparison with the application of sewage sludge, the input of lead and nickel from mineral fertilizers into arable soils is significantly lower. Approximately 80 % of total chromium from mineral fertilizers emanates from basic slag and basic slag potash. Regional differences in application rates and crops lead to differences in trace element loads per farmed area up to 6-fold. Further on, inputs from fertilizers have been compared with input by atmospheric deposition, based on data from 1989/90. On the whole, as a source of lead and cadmium, long-range transport via the atmosphere supersedes the input from mineral fertilizers, whereas in case of chromium, it is reverse.

Key words: fertilizers, trace element load, atmospheric deposition, Cd, Cr.