Assessing the potential toxicity for freshwater ecosystem from chemical protection of maize in different soil tillage systems

The aim of the study was to assess the impact of the use of plant protection products on the freshwater ecosystem in the production of maize for grain in different soil tillage systems. The analyzes were performed on the basis of data on chemical protection of maize in conventional tillage, reduced tillage and direct sowing. The data were obtained from 15 selected farms located in the Wielkopolskie Voivodeship. The studies were conducted in accordance with the life cycle assessment methodology. Using the PestLCI 2.08 model, emissions to the environment from the use of plant protection products were determined. The calculated emissions were used to assess the freshwater ecotoxicity potential using the USEtox 2.02 model. It was found that in all soil tillage systems, the largest stream of emissions of active substances to the environment was the amount of substances available for leaching and surface runoff, followed by emissions to air and emissions to groundwater. Herbicides were the main source of emissions from plant protection products used. A greater threat of toxic effects on the freshwater ecosystem was observed on farms producing maize for grain in direct sowing due to the greater use of herbicides than on farms with conventional and reduced tillage.