As a result of recreation in the forests of Krasno-yarsk Academic Town the tracks on which physical properties of the soil are subject to the greatest changes were formed. The determination of character and extent of these changes also made the main objective of the research. For its achievement researches of density, porosity and structure of the soil on a roadside and in the center of tracks in a birch forest mixed grasses, growing in the lower part of Krasnoyarsk Academic Town were conducted. Three upper layers of gray me-dium-thick loamy soils (0-5; 5--10; 10-20 cm) were studied using standard field and laboratory methodolo-gies. The results revealed greater increase of soil densi-ty in the center of trails, especially in the upper layer (1.36 vs 0.65 g/cm3 in control site), which negatively impacted the soil structure. Most of its aggregates ac-quire a plate-shaped form and grow larger to macro-structure size (more than 10 mm), the share of which reaches 34.3 %, while the content of the most valuable aggregates (2-5 mm) is 23.3 % with corresponding con-trol parameters 4.1 and 43.2 %. The same is observed in the 0-5 cm layer on the roadside, while in the deeper layers the differences with control sites are less signifi-cant. At the same time, the water resistance of the structure in them is somewhat lower (the coefficients of water resistance are 0.86-0.69 vs. 0.90-0.88 at the control site), which is caused by a lower content of or-ganic matter and humus. The increase of soil density on the trails and changes in its structure resulted in a cor-responding decrease of the total pore space (from 71.6-54.4 to 49.8-41.6 %) due to large non-capillary pores, the volume of which decreased from 45.9-22, 1 to 19.4-9.1 %. The latter is the main reason of the sharp de-crease in water and air permeability of the soil on the trails, as a result of which its water and air regime dete-riorates. Therefore, in order to minimize these negative phenomena, the improvement of trails is required to improve their soil physical parameters.
recreation, pathways, soil density, po-rosity, types of porosity, soils structure, deterioration of agrophysical parameters
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