Increasingly intensive and mechanized clear-cutting may deplete the forest ecosystem of essential nutrients. A clear-cut area near Växjö, southern Sweden, was investigated for changes in Mn, Cu and Zn in soil (NH4NO3 extractable and HNO3 soluble) and wavy hair grass (Deschampsia flexuosa) after conventional (CC) and whole-tree clear-cutting (WTC). The soil samples were mostly iron podzols. The area consisted of four clear-cut sites, respectively 2, 4, 6 and 8 years old, and an uncut forest reference stand. Each of the clear-cuts was split in two parts representing WTC and CC sites. Manganese showed the most definite trends after clear-cutting, exhibiting higher extractable concentrations in Oe, Oa and E horizons (4-8 years after clear-cutting) and B horizons (6-8 years after clear-cutting). The increase of exchangeable Mn in the E (2-8 years) and B (4-8 years) horizons was particularly strong. Zn concentrations tended to fluctuate with time. There was a tendency to higher Mn and Zn concentrations in the humus layer especially 2 years after CC-treatment compared with WTC, whereas the opposite trend was apparent for Cu. Mn, Cu and Zn concentrations decreased in Deschampsia flexuosa 2 years after clear-cutting, possibly due to increased soil pH.
