The rainfall erosivity is a worldwide challenge. Rainfall microstructure is one of the key properties of precipitation, which affects forest water balance and soil erosion, but it is rarely considered during the research processes.
The master’s thesis deals with the 14 - month period of precipitation measurements using two disdrometers above and below the birch tree canopy. We excluded erosive precipitation events from the obtained data, calculated the duration of individual events, obtained the amount of accumulated precipitation and determined data on the drop size, velocity and number of raindrops detected above and below the canopy. We also calculated the kinetic energy of precipitation and the erosion factor R of individual precipitation events and performed a comparison of potential soil loss in the case of precipitation above and below the tree canopy.
The results show that throughfall under the birch increasing with a longer duration of the precipitation event. The interception by the birch canopy was 33% of precipitation during the vegetation period, and 25% during the dormant period. Droplet sizes and velocities were generally higher above the canopy than below it throughout the period considered, but they largely retained their size and velocity as they passed through the canopy during the dormancy period. The kinetic energy of raindrops was maintained during the dormancy period as they passed through the canopy, while it decreased by 31% during the growing season.
During the vegetation period, the erosion factor R decreased by 50% when passing through the canopy, and during the dormancy period the value under the canopy decreased by 21%.