The effect of different tree plantings and soil preparation methods on contents of selected heavy metals in post-fire soils

Authors:

• Monika Jakubus,
• Zbigniew Kaczmarek,
• Jerzy Franciszek Michalik,
• Mieczyslaw Grzelak

Abstract

In the current study, we present contents of heavy metals determined in two upper post-fire forest soil horizons after an 8-year reclamation process. The study was conducted on selected plots established on a fragment of a large post-fire area developed after a total fire of a Scots pine stand in the Notecka Forest. Soil samples were taken from three plots, which differed in methods of soil preparation applied prior to seedling planting: I - no-till treatment (holes dug with a shovel), II - shallow ploughing with a disk plough, III - ploughing of furrows;- and in forest tree species used in artificial reforestation: P- pine (Pinus silvestris) and A - gray alder (Alnus incana). The performed analysis showed that concentrations of heavy metals in the podzolic-rusty soils occurring on the examined plots reached a similar level to that observed in such soils unaffected by a fire. The recorded changes in quantities of analysed heavy metals depended mainly on soil horizons, whereas the effect of soil preparation as well as tree species used for reforestation was found to be less significant. Among chemical elements analysed in the study; the lowest value was recorded for cadmium (range: 0.27 - 0.60 mg kg ^-1) irrespective of the tree species and soil cultivation methods. The highest concentration of lead was observed in the upper horizon of 0 - 0.1 m (range: 10.33 - 22.67 mg- kg^-1), whereas the highest zinc accumulation (range: 10.98 - 12.97 mg- kg^-1) was found in the deeper soil layer of 0.1 - 0.2 m. Generally, concentrations of Pb, Cu and Zn were lower in the 0.1 - 0.2 m layer in comparison with values recorded in samples collected from a depth of 0-0.1 m. © by PSP.