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Transformation of the natural environment of human life may have different speed, depending on the number of conditions, especially the climate. There is a long−term transformation, but also the sudden changes, often having for humans the nature of disaster. An example of sudden and undesirable changes in the environment are observed in form of movements of soil on the slopes of the mountain. One of the environmental factors that determine the slope stability is the current soil moisture. Its sudden increase caused by heavy rain or spring thaw can significantly change soil physical conditions and triger landslides. Water saturation may also occur in soils of these areas, to which water from the road drainage devices flows. The aim of the study is to determine the spatial distribution of soil moisture in the outlet of the drainage facilities for forest roads in the context of changes in selected soil characteristics affecting the possibility of landslides. We selected two culverts and two open top culverts that drain the forest road in Gorce National Park. The most important for the observations was to determine the spatial distribution of soil moisture and soil moisture differences in selected locations of an outlet of the road drainage facilities in relation to the place of outlet and the unit drain line. In the analysis of measurement results, there was no significant difference between the average humidity clustered according to ‘position' and by the ‘line'. The significance of this was obtained for the average moisture grouped according to ‘depth'. This can be explained by the impermeability of land and a large decrease in the slopes in the area of research. In general, rather small soil moisture fluctuations, despite the variability of rainfall, in conjunction with significant fraction of skeleton particles, do not create conditions conducive to the formation of landslides., Sylwan 160 (10): 861-870

The paper presents the results of the study of changes in the normal volume of absorption capacity of soil skeletons formed from the Magura sandstone in the Beskid Makowski area, and sampled from different genetic horizons. In the field of hydrology, the key issue in assessing the water storage capacity of the soil cover storage reservoir is the water storage capacity of the skeleton part. In the case of mountain soils, the issue of determining water storage capacity seems to be of importance due to the significant share of skeleton fraction in the soil cover. Moreover, the absorption capacity of the skeleton is related to the fraction volume. Soil test pits were executed in the area of Myślenice Forest District (southern Poland), in the habitat of Carpathian beech species Dentario glandulosae−Fagetum, in a stand of fir and spruce Abieti Piceetum. The scope of field work included sampling of 6 test profiles. In each profile, samples were taken from three identified genetic horizons. Sieve analysis method was used to determine the total content of skeleton and fine earth, and percentage share of each fraction. For each skeleton fractions, normal absorption capacity and bulk density were found. An important, supplementary part of the study was the isolation of fine−grained and coarse sandstone in each sample. After such processing, the collected material was compared with the material remaining after the successive stages of soil skeleton abrasion (weathering) in an aqueous medium, according to methodological assumptions. A device was used to perform this stage of the study. Changes in water storage capacity were mainly considered taking into account the fraction size and the location depth in a soil profile (without specifying the thickness changes). Differences were found between the absorption capacity of skeleton occurring naturally in the soil, and water absorption capacity of skeleton devoid of the outer layer of detritus as a result of the abrasion method. Water storage capacity values were decreasing after each successive step of the experimental run, along with increasing fraction size and the depth of their position in the profile. Preliminary results showed that the changes of absorption capacity are more strongly correlated with size of the fraction than with position in a genetic horizon., Sylwan 159 (6): 452-460

The paper analyses the possibilities of using the forest soil descriptions included in the forest management plan to draw up an initial characterization of the area in terms of their usefulness for the forest road building. That kind of data may be used in the planning of forest road network in preliminary location concept of road sections. Knowledge in the subject of the spatial distribution of ground with specific physical properties enables us to offer such options, that are likely to ensure the stability of built facilities and also lower costs of implementation and operating as well as reduce the environmental costs of the investment. The paper shows the possibilities and ways to determine the basic characteristics of the ground, such as: the type of ground, filtration coefficient and vulnerability to frost heave. Forest soil descriptions based on macroscopic studies should be regarded as insufficient. Use of the soil data is possible and gives the desired effect only when the results of the grain size analysis can be used. On the basis of these data, classification of the ground can be performed and one can determine the basic indicators of the suitability of the tested materials. We used twelve soil samples with the diverse texture (10−89% sand, 7−83% silt and 4−29% clay). On the basis of complete pedological data collected in accordance with the recommendations of the Forest Management Instruction, it was possible to classify the material in terms of engineering and calculation of relevant indicators and characteristics. It should be noted that this is the initial characteristics of the soil and as such it is not a substitute for detailed research required for the execution stage of the project of specific road sections., Sylwan 159 (6): 461-468