Enzymatic activity and metabolic potential of microorganisms in flood-affected soils analysed in the short and long term after flooding – preliminary studies

Abstract Floods are becoming increasingly common in Poland and throughout Europe. The microbiological activity of flooded soils changes, but research in this area, especially long-term research, is lacking. This experiment aimed to compare the enzymatic and metabolic activities of soil microorganisms in two flood-affected fields in the Lower Silesia and Opole voivodeships in 2024. Soil samples were taken seven days and seven months after the floodwaters receded. Dehydrogenases activity, acid and alkaline phosphatases activities, and metabolic potential of microorganisms were determined. It was demonstrated that the activity of the measured enzymes in both soils was lower in 2024, seven days after the flood, compared to the activity measured seven months later. However, metabolic activity was higher seven days after the flood than in 2025, although the statistically significant difference only concerned soil O1 measurements. Although these studies only provide a preliminary insight into the basic parameters of soil biological activity, they enable us to observe trends in changes to the soil following flooding and emphasising the importance of long-term research.