Precipitation interception, the process by which various vegetation retains precipitation, greatly affects natural processes (e.g. soil erosion). When dealing with precipitation, it is important to consider the microstructure of precipitation, since precipitation is a process consisting of a finite number of individual drops that appear in different sizes and fall at different velocities. Precipitation data were obtained with the help of 1-minute measurements of three disdrometers (under the birch canopy, under the pine canopy and above them). The considered period (between July 12, 2022 and February 16, 2023) was divided into 48 rainfall events, and then the rainfall duration, amount of precipitation, average intensity of precipitation, and microstructure of raindrops (size, velocity, and number of drops) were calculated for individual events. Finally, we calculated kinetic energy (KE), maximum 30-minute intensity (max I30) and rainfall erosivity factor (R). All variables were calculated for data above and below both canopies. It can be seen from the results that the interception of precipitation decreases with the duration of the events for both birch and pine tree. The size of droplets increased as they passed through the tree canopy during the vegetation season. During the leafless period, however, they decreased, but the diameter of the drops increased compared to the entire considered period (under the birch tree by 46 %, under the pine tree by 25.5 %). Droplet velocity decreased on average by 38 % under the pine tree. Under the birch tree, however, it increased by 0.7 %, which is the result of an increase in the average speed under it during the dormant period (by 7 %). From the obtained results, we found that the rainfall interception has a great influence on soil erosion, since the rainfall erosivity factor (R) was significantly reduced when raindrops passed through both tree canopies.
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