Abstract
Six years after application of ammonium nitrate and urea to a podzolic soil, samples from the humus layer (A01/A02) were extracted with ethanol or diethyl ether, and the extracts were pyrolysed. The pyrograms were statistically analysed with a pattern recognition computer program (SIMCA). Pyrolysis of ethanol extracts resulted in pyrograms that allowed separation between control soil and ammonium nitrate-treated soil. Pyrograms of ether extracts allowed separation between urea-treated and control soil. The results indicate that the methodology can be used for separating closely related soils.