Composts and Water Extracts of Lignocellulosic Composts in the Aspect of Fertilization, Humus-Forming, Sanitary, Phytosanitary and Phytotoxicity Value Assessment

摘要

Purpose Lignocellulosic biomass waste is produced in large quantities and only a small part is used for utility purposes. The aim of the work was to assess the fertilization value of the solid fraction and water extract of lignocellulosic composts. Methods Compost I contained 42.86% pine bark, 34.28% grass, 20.0% sawdust and 2.86% chicken feathers; compost II contained 25.54% pine bark, 10.63% wheat straw, 51.07% sawdust and 12.76% chicken feathers. Seldom described physical properties and phytosanitary and sanitary status of composts as well as macro- and micronutrients and heavy metals concentrations were determined in the solid fraction and water extracts of composts and their impact on the germination of Lepidium sativum L. using PC analysis. Results Composts were characterized by good physical properties and a light product, safe phytosanitary status, which was related to the prevalence of potentially antagonistic fungi, especially in compost II. The frequency of Aspergillus fumigatus, considered an opportunistic human pathogen, decreased during the composting. Heavy metal concentrations did not exceed permissible values for improvers and cultivation media in the solid and aqueous compost fractions. The tested composts were sanitary safe. Both composts were non-toxic to plants, because the germination index in compost I was 70-195% and 95-195% in compost II. PCA analysis demonstrated that the majority of micro- and macronutrients and heavy metals had a significantly negative effect on root elongation and germination of the test plant (cress) seeds, especially in compost I. Conclusions Lignocellulosic waste after composting is a valuable and safe organic fertilizer.