Authors:
PhD Mónika Molnár | Budapest University of Technology and Economics | Hungary
PhD Viktoria Feigl | Budapest University of Technology and Economics | Hungary
Éva Ujaczki | Budapest University of Technology and Economics | Hungary
Orsolya Klebercz | Budapest University of Technology and Economics | Hungary
Mária Tolner | Budapest University of Technology and Economics | Hungary
Emese Vaszita | Budapest University of Technology and Economics | Hungary
Katalin Gruiz | Budapest University of Technology and Economics | Hungary
Biochar produced from a wide range of organic materials by pyrolysis has been widely reported as a means to improve soil physico-chemical properties, fertility and crop productivity moreover to mitigate climate change. However, the effects of biochar on soil ecosystem and microbial activity have received much less attention than its effects on soil physico-chemical properties.
The key objective of this research was to determine the effect of biochar amendment on physico-chemical properties of sandy acidic soil as well as on activity of soil biota. Laboratory microcosm experiments were conducted to improve soil quality combining variations in biochar amounts and fertilizer application rates (N and P).
The biochars applied were produced in a PYREG® type pyrolyser at temperatures between 450 and 700 °C during 15-20 min residence time from different feedstocks such as grain husks, paper fiber sludge, wood screenings, vine, black cherry, natural biomass, straw, olive stones and meadow.
The main purpose of soil technological microcosms was to assess efficiency and applicability of different biochars as soil amendments prior to field trials and to choose the best biochars that are able to improve the fertility, biological activity and physical propoerties of degraded soils particularly acidic sandy soil furthermore to determine the optimum technological parameters in microcosms.
To assess and evaluate the potential benefits and feasibility moreover risks of biochars on soil an integrated approach was applied including physical, chemical, biological and ecotoxicological methods: water holding capacity, pH, EC, elemental concentrations, nutrient supply, nitrification, soil respiration, CO2 production and specific cell concentrations as well as toxicity for bacteria (Aliivibrio fischeri), plants (Sinapis alba and Triticum aestivum) and animals (Tetrahymena pyriformis, Folsomia candida) were determined in soil microcosms.
Acknowledgement:
The work was carried out in the frame of the „Terra Preta” project, registration number HU09-0029-A1-2013 supported by the EEA Grants and the Norway Grants within the „Green Industry Innovation Program” of the Norwegian Financial Mechanism 2009-2014.