Logging equipment and method have a major influence on harvesting productivity and cost. This study investigated the productivity and operational costs of tree-length cable yarding system using HAM300, a domestically developed tower yarder. We tested HAM300 for thinning operation in Pinus densiflora stands at Gangreung, Gangwon-do on April, 2014. To assess the productivity we conducted time study for each stage of the operation. When the average time/cycle was examined for each stage of the operation, the longest was for yarding (241 sec), followed by delimbing (237 sec), felling (153 sec), and processing (103 sec). Furthermore, productivity for felling was 8.6 m 3 /hr, followed by delimbing (5.1 m 3 /hr), yarding (3.5 m 3 /hr), and processing (8.1 m 3 /hr). The total cost for the tree-length logging system was 58,446 won/m 3 , of which the majority was incurred by the yarding cost at 46,217 won/m 3 (79.3%), whereas the lowest cost was for felling at 2,359 won/m 3 (4.1%). We suggest that it is necessary to foster specialized operators and provide training in operating the tower yarder thereby implementing efficient harvesting system resulting from low-cost yarding.

Existing forest roads that are the base infrastructure foundation for forest management have been built with a focus on structural stability rather than ecological impact. In recent, however, the concerns on the ecological and environmental impacts on the forest road construction has been increased with the emphasis of sustainable forest management and the improvement of public awareness. Especially, the cut slopes that occurred on the forest road construction are known to affect the movement and habitat of wild animals living in the forest. This study aims to establish environmental and structural standards for the cut slopes by identifying the effect of forest road cut slopes on the movement of wild animals based on a survey of national forest roads in South Korea (30 km in total). Seven factors associated with forest road cut slopes, including cut slope length, cut slope gradient, soil type, longitudinal position, crossing position, aspect, and vegetation coverage, as well as wildlife tracks were investigated. As a result of statistical analysis using cross tabulation to determine the correlation of wildlife tracks with each cut slope factor, five factors (soil type, cut slope gradient, cut slope length, vegetation coverage, and crossing position) were significantly identified. Using these five factors, a prediction model to predict whether wildlife move or not on the cut slope was developed, and the discriminant hit ratio was 76.0%. Thus, using such models, there is a need to develop the guidelines of forest road installation considering the wildlife movement and of ecological corridor installation for more eco-friendly forest road construction and design in the future.

No abstract