Influence of biomass ash fertilization on soil pH, CaCO3, K2O and P2O5 under Miscanthus x giganteus

Abstract

The cultivation of energy crops and the use of biomass ash are part of a sustainable energy economy and have a major impact on the environment. Biomass ash can be used as a soil conditioner due to its chemical composition with essential micro- and macronutrients and has a proven positive effect on the physicochemical properties of soils. With the increasing interest and use of bioenergy species, the production of biomass ash is also increasing and is expected to increase further in the future. Therefore, the correct use of this product is important. Ensuring its use to enrich soils will strengthen the ecological aspect and close the gaps in the circular economy. In this context, investigating the influence of biomass ash on individual soil properties under different agro-ecological conditions is important to determine its possible uses and limitations. The aim of the study was therefore to determine the influence of different ash dosages (2 and 5 t/ha) on soil pH, carbonate content (CaCO3), the content of plant-available phosphorus (P2O5) and plant-available potassium (K2O) under the perennial energy crop Miscanthus x giganteus. The study was conducted in the years 2016-2019 in the continental part of Croatia near Zagreb city. The study showed that the application of ash had no significant effect on soil pH, but did have an effect on CaCO3, P2O5 and K2O. At both ash doses studied, there was a significant decrease in P2O5 and a significant increase in CaCO3, while the K2O content only increased significantly at the higher ash dose compared to the control treatment. Biomass ash proved to be a good soil conditioner in terms of CaCO3 and K2O content under the agroecological conditions studied. Further studies on various agroecological conditions such as soil types, vegetation and climate will provide further insights into the effective use of biomass ash. Likewise, research on the influence of biomass ash on other important soil properties in combination with studies on plant uptake is necessary to understand the complex interaction of biomass ash.

Keywords

• forest biomass ash
• chemical soil properties
• perennial energy grass
• sustainability
• circular economy