COMPARISON OF SOIL LOSS DUE TO WATER EROSION BEFORE AND AFTER A CHANGE IN AGRONOMIC PRACTICES

Between September 13th and 16th, 2024, heavy rainfall led to widespread flooding across the municipalities in the Senica district, as well as significant soil erosion on intensively farmed arable land. According to data from the Slovak Hydrometeorological Institute (SHMU), the Senica district received a total of 230 millimeters of precipitation during this period. In the village of Smolinske, located in the lowlands of Zahorie in western Slovakia, experienced substantial flooding of agricultural areas, leading to considerable surface and gully erosion across many agricultural parcels. In this study, we present the effects of this rainfall on soil block 5002/1 Sastin (LPIS designation), with a total area of 34.86 ha. In the area, we conducted a detailed unmanned aircraft system (UAS) flight from a height of 70 m, producing an orthophotomosaic that depicted the erosion-damaged areas. These areas were vectorized and used to verify the results of the erosion rate calculation. The calculation of water erosion was performed using the Universal Soil Loss Equation methodology. The K and R factors were determined based on tabular data derived from the national soil rating system (BPEJ) and on the data of the rainfall measuring stations. The LS factor was derived from airborne laser scanning data based on DMR5.0 (1 m resolution). The support practice - P and cover management - C factors were determined through field reconnaissance conducted during the flooding event. The estimated soil loss was approximately 2.5 t.ha-1.yr-1. The proposed change to the status was implemented by altering the current land management. We proposed the measure of strip crop rotation, which significantly affects the C and P factors. The erosion loss calculation was again carried out. The two outputs were compared, and the differences were balanced. The results suggest that even a "simple" change in agrotechnical measures can mitigate the effects of extreme events.