ŠKOLEK Matúš: Impact of biomass derived from tree harvesting on properties of sandy soil in Záhorie lowland. (Diploma thesis) Supervisor - doc. Ing. Erika Gömöryová, CSc., Technical university in Zvolen, Faculty of forestry, Department of Natural Environment. 2021, 70 p. In our diploma thesis, we focused on comparision of soil properties in two pine forests of the similar age. In the forests, different kind of mechanization for tilling the soil – milling and backfilling of tree stumps and another biomass deriving from tree harvesting into the soil by buldozer were used. The forests differ in quality and also microclimate. We collected soil samples at plot from these two stands in 2020. Then we took sandy soil samples to the laboratory, where we determined: soil reaction, soil moisture and content of total C, N, S, exchangeable K, Mg, Ca and plant available phosporus in soil. At the same time, we estimated C/N, C/P and C/K ratio. Among the physicio-chemical attributes, the biggest differences were found in soil moisture, content of C, N and also in P. In pine forest, where the soil was milling, bigger content of organic matter was observed – this forest has more favorable water holding ability.