Animal logging is one of the most ancient wood extraction methods and it is still applied in different parts of the world, including industrialised countries. Animal logging is often imagined as a low-impact method and sometimes, or rather often, it is recommended as a best-management practice. However, the literature findings depict a more complex scenario, and the goal of the present review is to shed light on the topic of environmental sustainability of logging operations performed by animals. Usually, animal logging causes less pollutant emissions and less damage to the residual stand in comparison to ground-based mechanised extraction methods. However, when applied in commercial forestry interventions such as coppicing, animal logging showed levels of soil compaction in line with those of ground-based machinery like tractors, skidders and forwarders. Specifically developed trials revealed that in the animal skid trails a strong disturbance to the soil microarthropod community occurred. Furthermore, the soil features in the animal trails seemed to get worse over time after logging, thus suggesting the possible presence of strong localised erosion along these trails. Despite the strong need to further investigate this topic, concerning the ecological aspects of forest soil which were generally neglected by the literature, the use of animal logging can be recommended in the case of small-scale forestry with wooden material sparsely located throughout the logging site. In the case of commercial logging on steep slopes instead it is recommended to replace animal logging with cable-based extraction systems.

The behavior of the vehicle-soil interaction and reduction of the possible soil damage to an acceptable level is one of the goals of forest engineering. This study aimed to analyze the impact of a 6-wheeled forwarder on water-physical soil characteristics on lowland soil - pseudogley. The research was conducted using a 17-ton Timberjack 1710B forwarder, which forwarded 694.1 m3 volume of oak (Quercus robur L.) assortments. Soil characteristics were measured after each of the eight passes of the loaded forwarder. Bulk density measured on the surface layer ranged from 1.01-1.23 (Me=1.10) g/cm3 (undisturbed soil); 1.14-1.70 g/cm3 (multiple passes of the loaded forwarder). The highest soil density increase was observed after the first pass of the loaded forwarder (16%). Soil solid phase ranged from 2.49 to 2.73 g/cm3 with no statistically significant difference between undisturbed soil and soil after multiple passes of the vehicle. The highest porosity decrease was observed after the first pass of the loaded forwarder (10%). The highest soil water retention capacity decrease was observed after the first pass of the loaded forwarder (3%). The highest soil air capacity decrease was observed after the first pass of the loaded forwarder (30%) compared to the undisturbed soil of the forest stand.