Impacts of modern mechanised skidding on the natural and cultural heritage of the Polish Carpathian Mountains

- LiDAR confirmed to be an adequate tool by which to map networks of logging roads under the tree canopy.
- The density of logging roads in the Carpathians is among the highest reported in the literature.
- Due to skidding, 5% of the forest analysed has had its surface topography altered.
- Skidding now appears to be a bottleneck of sustainable forest management in the Carpathians.
- Actions aimed at mapping and preserving the cultural heritage of forests are needed urgently.

The aim of the research was to determine the scale and forms of logging road impacts on the natural environment and residual cultural heritage of Ruthenian Highlanders that characterise the Polish part of the north-eastern Carpathians. To this end, we used LiDAR-derived DEM to detect and map forest roads and skid trails, and to estimate road density, in 60 forest divisions sampled at random from among the 2639 km2 of forest managed in the above region by the State Forests National Forest Holding. The determined road network was then validated by GPS ground control. Supplementary, detailed LiDAR data were used to detect features of the past cultural landscape, and to determine the interference in that due to contemporary logging roads. Overall skidder traffic was estimated on the basis of a thorough analysis of State Forests documents, including legal acts, guidelines, management plans, detailed databases and maps of planned cuts.LiDAR data proved to be an adequate tool in the mapping of the network of logging roads present under the tree canopy, although it slightly underestimates road density in a densely vegetated, post-landslide topography. Our LiDAR-assessed density of Carpathian logging roads (at 108.5-140.7 m ha−1, including skid trails) is nevertheless among the highest reported in the literature, and one that far exceeds recommended values. Spatial pattern analysis further revealed the unfavourable phenomenon of multiple parallel roads forming contiguous areas of disturbed soil and constituting dispersal paths for invasive plants. Many examples of cultural remains being run over and destroyed by skidders could also be reported.The observed process of log extraction is one of the least sustainable aspects to forest management in the Carpathians, and our results emphasise very clearly the need for rules to support the preservation of cultural heritage in forested areas, as well as improved tools by which skidding practices can be monitored.