Impact Assessment of Skidding Extraction: Effects on Physical and Chemical Properties of Forest Soils and on Maple Seedling Growing along the Skid Trail

Several studies investigated soil disturbances caused on skid trailsby forest logging. However, there is still a lack of knowledge about the severity and the distance of disturbances along both sides from the trails. The aimsof this study were: i)to investigate the changes in physical and chemical properties of soil along the sides of skidding trails; ii) tomeasure the effects of soil compactionon of maple seedlingsgrowth.Two levels of trail gradient (< 20% and >20 %), four levels of traffic frequency (3, 8, 15,and 30 passes) and four distance buffer stripzones (0.5 m intervals from 0 to 2 m in distance) on both sides of skid trail edges were analyzed. Each treatment included three replicate plots. In order to investigate the effect of compactionon seedlings emergence and growth, maple seeds were sown after logging. The results highlighted significant changes in physical and chemical properties of soil foreach traffic frequency in theclosest buffer strip (from 0 to 0.5 m from the skid trailedges). The largest changes in soil properties were identified at 0.5 m distance zones for a slope gradient > 20% after 3, 8, 15,and 30 skidding cycles. The highest changes were recorded onslopecategory >20%.The higher the soil compaction the lower the germination rate, root length, and stem height of seedlings.