Influence of Ponsse Gazzelle forwarder passes on 2 the soil environment and soil deformation

: During the harvesting and skidding process, machine runs have a strong influence on the 6 soil environment. The study analyzed the influence of 20 runs of the Ponsse Gazzelle forwarder on 7 the change of soil compactness, moisture and deformation. The research were carried out in Gidle 8 Forest District, located in southern Poland. Analyzed areas was differing in soil type and 9 hydrological conditions. On the investigated forest areas control sections were established for 10 measurements.The data of changes in soil compactness were gained by using a handheld 11 penetrometer at a depth of 10 and 20 cm. The soil compactnes were measured after each forwarder 12 pass. Soil moisture was also assessed at a depth of 10 and 20 cm before the start of the forwareder 13 operation, and after 20 passes. To obtain data for determining soil deformation UAV were used. 14 Terrain models were created using Agisoft Metashape software. From the generated 3D terrain 15 models, changes in the cross-sections of operational routes were determined.The data were 16 subjected to statistical analysis to determine the relationship between the rate of changes in soil and 17 terain conditions. The increase of soil compactness was linear on all the examined plots. Statistically 18 significant differences were found in the soil compaction rate.After 20 runs of the forwarder, the 19 humidity in the tested sections decreased almost 3 timesCorrelation analysis showed a moderate 20 relationship with the extent of soil deformation and the type of soil 21 and the type of forest habitat.


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The use of forwarders during forest work enabled a significant increase in the efficiency of

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The aim of the research was to analyze the influence of 20 forwarder runs on soil moisture and 36 increase of its compactness. By using aerial photography and geomatic software, an analysis of the 37 logging area, distribution and condition of the network of logging routes was carried out.

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The research was carried out in the Gidle Forest District in the southern Poland. For the study, 40 4 cutting areas were selected, differing in the type of soil, stand type and site wetness index (Tab. 1).

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This model is equipped with a camera with a 1-inch CMOS sensor and a resolution of 20 megapixels, 57 allowing to take photos with a maximum resolution of 5472 × 3078 pixels. The flights were made at 58 an altitude of 30 meters, and the overlap index of the photos was 80%, both horiontally and vertically.

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The obtained photos were used to create digital elevation models [DEM] of the terrain and 60 orthomosaic using Agisoft Metashape software. Obtained data allowed to create numerical models 61 where a single pixel represents a square with a side of 1.5 cm in the terrain. By assesment of 62 orthomosaics in Qgis te the skid trail area, lenght and codition was analyzed. By analyzing the DEM 63 in Qgis software, the soil displacement and rutting depth during forestry work was determined.

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R studio software was used to perform statistical analyzes. The Kruskal-Wallis test was used to 65 determine the significance of differences between the studied surfaces. The correlation was calculated 66 using Pearson correlation test.

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The forwarder travels had a greater impact on the compactness of the soil at a depth of 20 cm 80 than on the depth of 10 cm, regardless of the tested section on all tested surfaces.

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In the left and right rut, the pace of increasing soil compaction was similar in all sections. In 82 some cases, soil compactness increased almost 4 times at a depth of 10 cm and almost 5 times at a 83 depth of 20 cm. The t test proven that there is statistically significant differences between soil density 84 before and after 20 forwarder passes (p value = 0,0000).

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At a depth of 20 cm, a greater ingresem in compactness can be noticed and that the forwarder 86 wheels have a stronger impact on the ground between the ruts (Tab. 2).

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On the examined plots, differences were found between the area declared and the area measured 102 on the basis 103 of orthophotomaps (Table 4). There was an average of 0.91 km of skidding trails per 1 hectare of the 104 studied site. These values are in the range of 0.67 to 1.00 km / ha (Table 4). During the research, the 105 area of the operational routes was determined, on which deformation and damage to the soil 106 structure caused by machine passes can be expected. Moreover, the area of places where machine 107 runs caused the uncovery of the mineral layer of the soil were identified (Table 4.).

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The kruskal-wallis test was used to assess whether there were any statistically significant