Soil Recycling of Waste Biomass in the Production of Malus domestica Fruit Tree Seedlings

The production of fruit tree seedlings generates waste wood biomass, which results from the pruning of budded rootstocks in the first year of the two-year production cycle. This study proposes a new method of managing this biomass by recycling the wood chips (2, 3 and 5 t ha-1) back into the soil. The impact of different wood chip doses on selected physicochemical soil properties after the production process (especially soil organic carbon content (SOC), as well as the quantity and quality of the produced Malus domestica fruit tree seedlings, was determined. The recycling of waste biomass contributed to enriching the soil with additional components, mainly organic carbon with the potential for biotransformation into humic substances. The applied doses of wood chips, in amounts of 2, 3, and 5 t ha-1, resulted in an increase in SOC content compared to the control by 21.5%, 22.5%, and 35.8%, respectively. Additionally, the recycling of waste biomass introduced other compounds important for plant growth and development into the soil, particularly iron, zinc, magnesium, and manganese. It should be noted that the proposed method of managing waste biomass generated during the apple tree seedling production stage resulted in reduced production costs while maintaining high production indices.