Physical Properties of Texturally Different Soils After Application of Biochar Substrates

Scientific studies show that the efficiency of biochar can be improved by its combination with other fertilisers. For this reason, fertiliser manufacturers are working to create products that combine biochar with other soil fertility enhancers suitable for different soil-climatic conditions. In this study, two types of biochar substrates (1. biochar blended with farmyard manure, and 2. biochar blended with farmyard manure as well as with digestate) at rates of 10 and 20 t/ha were applied alone or in combination with other manure and mineral fertilisers. These were added to Arenosol (sandy soil, Dolná Streda, Slovakia) and Chernozem (loamy soil, Veľké Úľany, Slovakia) to evaluate the soil physical properties to test the potential of these amendments for soil amelioration in texturally different soils. The results showed that the application of biochar substrates alone increased soil moisture, the volume of capillary pores, and decreased aeration and volume of non-capillary pores. The application of biochar substrates with mineral fertilisers increased aeration, content of water-stable macro-aggregates (WSA_ma), total porosity, and decreased soil moisture and the content of water-stable micro-aggregates (WSA_mi) in sandy soil. In loamy soil, when compared to unfertilised control, the biochar treatments increased content of WSA_ma, content of dry-sieved macro-aggregates, and decreased content of WSA_mi and content of dry-sieved micro-aggregates. The combination of biochar substrates together with manure had no effect on changes in the physical properties of loamy soil.