Identification of organic matter from peat, leonardite and lignite fertilisers using humification parameters and electrofocusing

The organic matter extracted from peats (P), leonardites (Le) and lignites (Li) was characterised by humification parameters and electrofocusing (EF). The degree of humification and the humification index might be used to distinguish P from Le and Li, but not Le from Li because they showed overlapped values, while the humification rate could be used only for the identification of Le and EF profiles of P, Le and Li fertilisers revealed different band patterns: P samples did not show bands in the region with isoelectric point, pI > 4.4; Le samples showed very intense bands in the region with pI > 4.4; Li samples showed a very different band pattern with poorly resolved bands in the region with pI > 3.8. P, Le and Li samples can be distinguished by combining humification parameters and EF. (C) 2002 Elsevier Science Ltd. All rights reserved.