INFLUENCE OF SOIL SAMPLING TECHNIQUES ON THE RESULTS OF HEAVY-METAL TRANSPORT INTO THE SUBSOILS AFTER LONG-TERM APPLICATION OF SEWAGE-SLUDGE

In a long-term field experiment with application of sewage sludge on a loess derived Luvisol samples from the subsoil (30 cm to 60 cm) taken with a 1-partite ''PORKHAUER'' auger had higher total contents of Cd, Zn and Pb than samples taken with a 3-partite ''Nmin'' sampler. The h igher heavy metal contents in the subsoil samples taken with the ''PUR KHAUER'' auger are obviously due to contamination of the subsoil sampl es by topsoil and thus overestimate the transport of heavy metals in t he soil profile. After longterm application of sewage sludge the actua l transport of dissolved Cd into the subsoil of the Luvisol is probabl y not higher than 10 g to 20 g ha(-1) a(-1).