Effect of organic amendments on soil characteristics and maize biomass in a greenhouse experiment

Maya Benkova, Lyuba Nenova, Tsetska Simeonova, Milena Harizanova and Irena Atanassova

Abstract: A pot experiment was performed with maize on Fluvisol. The aim of this study was to establish the effect of some soil organic amendments on the chemical properties of Fluvisol and maize biomass. Three organic products were used as ameliorants – biochar, compost of plant residue and sewage sludge and added in increasing amounts (1%, 2.5% and 10%) to the weight of soil. A soil without ameliorants was used as control. The results of the vegetation experiment with maize showed that organic amendments lead to improvement of soil properties. All amendments increased soil pH by 0.2-0.7 units, and the medium (2.5%) and highest rate (10%) of biochar and compost increased CECsa and % base saturation. The study showed that the tested organic amendments increased the ameliorative efficiency of the treatment carried out. The application of compost and sewage sludge resulted in an increase in soil available K and P, but only the addition of compost increased soil available N. The application of the three organic amendments affected plant nutrient accumulation, especially with respect to N and K, when higher rates were added. The highest percentage of the studied elements was observed in the variants with the maximum dose of ameliorants. Biochar had the least impact on maize biomass growth. The compost and the sludge were found to be equally efficient at 10%, resulting in an increase in the maize biomass. It can be concluded that compost had a greater impact on soil chemical properties, available forms of nutrients and maize growth compared to the other two organic amendments.

Keywords: biochar; biomass; compost; maize; sewage sludge; soil characteristics

Date published: 2023-02-23