Wood Biomass Ash (WBA) from the Heat Production Process as a Mineral Amendment for Improving Selected Soil Properties

Abstract

This research concerned the possibilities of the natural management of ash, which is a waste product obtained in the process of burning wood chips in a bio-heating plant. The basis of the research was a pot experiment, which was carried out in a greenhouse of the University of Warmia and Mazury in Olsztyn, Poland. This experiment dealt with the influence of increasing doses of wood biomass ash added to soil on selected soil properties. The soil used for the pot experiment was taken from the arable layer (0–25 cm) of the soil. It was characterized by acidic reaction, low salinity, and an average content of total carbon (TC). The test plant was corn. Soil analysis after plant harvest showed an increase in pH and a significant improvement of soil sorption properties, without causing an excessive increase in soil salinity. In addition, a significant increase in the content of available K, P, and Mg was observed, which at the highest dose of WBA reached: 121.9; 109.3, and 41.33 mg kg−1 of soil, respectively. The content of trace metals: iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), cadmium (Cd), lead (Pb), cobalt (Co), chrome (Cr), and nickel (Ni) in the soil was quite varied but did not exceed the permissible values for agricultural soils. The content of available forms of these trace metals at the highest dose of WBA was, respectively, 1004, 129.9, 8.70, 2.08, 5.54, 0.195, 1.47, 0.97, and 1.92 kg−1 of soil. The results confirmed the significant fertilizing potential of wood biomass ash.