• Journal of Forest and Environmental Science
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• v.33 no.2
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• pp.147-153
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• 2017

The purpose of this study was to examine productivity and cost of tree-length harvesting using cable yarding system in a larch (Larix leptolepis) clear-cutting stand located in Pyeongchang-gun, Gangwon-do. We used tree-length harvesting method using cable yarding system with a tower yarder HAM300. The productivity was $17.6m^3/hr$ for felling, $12.4m^3/hr$ for delimbing, $4.2m^3/hr$ for yarding, and $8.1m^3/hr$ for processing. The total cost of the harvesting system was $48,381won/m^3$, which was majorly composed of yarding operation cost, at $40,169won/m^3$ (79.3%), while felling had the lowest cost at $1,154won/m^3$ (4.1%). Major factors affecting felling and processing productivity was tree volume and the number and thickness of branches for delimbing productivity. In addition, we suggest that training and education for machine operators were critical to improve yarding productivity.

• Journal of Forest and Environmental Science
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• v.28 no.2
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• pp.106-117
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• 2012

In an effort to analyze the impact of climate change, Gangwon provincial forest was divided into three sectors; forest ecology, forest disaster, and forest productivity and analysis of their current status from 2000 to 2009 and vulnerability assessment by climate change has been carried in this study. In case of vulnerability assessment, except for the forest ecology, forest disaster (forest fires and forest pests) and forest productivity sectors were analyzed in current status, the year of 2020, and 2050. It turned out that vulnerability of forest fires in the field of disaster would become worse and forest pests also would make more impact even though there is some variation in different areas. In case of the vulnerability of forest productivity there would be not a big difference in the future compared with current vulnerability. Systematic research on the sensitivity index used for vulnerability assessment is necessary since vulnerability assessment result greatly depends on the use of climate exposure index and adaptive capacity index.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.37-51
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• 1998

This study was carried out to lead the scientific management of the urban forest by estimating the forest environment. Forest environmental information was constructed using IDRISI system based on survey data, soil, plant, and digital elevation data. Forest environmental information was consisted of soil depth, soil organic content, soil hardness and parent rock as a soil environmental factor, and forest community, tree age, crown density as a plant environmental factor. Plant activity and topographic environment also were analyzed by using remote sensing data and digital elevation data. Environmental function of urban forest was estimated based on results of soil conservation and forest productivity. 70% of urban forest is located in elevation of lower than 200m and 55% of forest area have the slope of lower than 15 degree. Analyzed soil conservation status and forest productivity were almost the same as the soil chemical properties of collected soil sample and the vegetation index estimated using remote sensing data, respectively. Thus, the constructed forest environmental information could be useful to give some ideas for management of urban forest ecosystem and establishment of environmental conservation planning, including forests, in Taejon. The best forest environmental function was appeared at the natural ecology preservation zone. Current natural parks and urban parks were appeared to establish the environmental conservation plan for further development. The worst forest environmental function was appeared at the forest near to the industrial area and an overall and systematic plan was required for the soil management and high forest productivity because these forest was developing a severe soil acidification and having a low forest productivity.

• Journal of Korean Society of Forest Science
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• v.113 no.2
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• pp.164-169
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• 2024

In South Korea, most felling operations involve the use of chainsaws due to steep and rough terrains. This felling technique is responsible for approximately 80% of all fatalities mainly due to unpredictable felling directions. Therefore, readjust monitorised felling is imperative to improve safety in different working conditions. This study examined the effect of wedging on felling direction error and productivity during felling operations. When wedging was applied, a felling direction error within 22° and a productivity of 0.63 m³/min were obtained. These results show a decrease in mean directional error and a dimish in productivity. Thus, although wedging reduces productivity, it is a necessary strategy to improve safety.

• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.300-309
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• 2017

The productivity, cost, and optimal forest road network density for tree-length yarding with K301-4 and HAM300 tower yarders were analyzed. The results showed that productivity decreased as the yarding distance increased. The productivity of the K301-4 was greater than that of the HAM300 as the maximum yarding distance was longer than 34 m. This difference increased as the load volume increased. As the K301-4 yarder had a higher purchase price and it took more time to set up compared to the HAM300, the HAM300 was cost effective. Therefore, in oder to introduce tower yarders to reduce operational cost, it is effective to increase the load volume during operations and to utilize the road network repeatedly for a long period.

• Journal of Forest and Environmental Science
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• v.32 no.3
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• pp.291-301
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• 2016

One of the most concerned topics in ecology is the relationship between biodiversity and ecosystem functioning. However, there are few field studies, carried out in forests, although many studies have been done in controlled experiments in grasslands. In this paper, we describe the relationship pattern between three facets of diversity and productivity at Ratargul Fresh Water Swamp Forest (RFWSF) in Bangladesh, which is the only remaining fresh water swamp forest of the country. Sixty sample plots were selected from RFWSF and included six functional traits including leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), tree height, bark thickness and wood density. In analyzing TD, we used Shannon diversity and richness indices, functional diversity was measured by Rao's quadratic entropy (Rao 1982) and Faith's (1992) index was used for phylogenetic diversity (PD). It was found that, TD, FD and PD were positively related with productivity (basal area) due to resource use complementarity but surprisingly the best predictor of tree productivity was FD. The results contribute to the understanding the effects of biodiversity loss and it is essential for conservation decision-making and policy-making of Ratargul Fresh Water Swamp Forest.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.107-112
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• 2014

The productivity and cost of clear cutting operations were examined to broaden our knowledge on the harvesting system in a Larix leptolepis stand of Korea. The harvesting system was divided into tree operations which were chainsaw (STIHL MS440) felling, tower yarder (Koller301-4) yarding and harvester (WOODY H50) processing. The average cycle time of felling, yarding and processing were 98 s/cycle, 245 s/cycle and 150 s/cycle. The total stump-to-pile operational productivity was 43.07 $m^3/hr$. The highest production activity was the felling 17.93 $m^3/hr$, followed by the productivity of processing 15.62 $m^3/hr$ and then by the productivity of yarding 9.52 $m^3/hr$. In addition the total stump-to-pile operational cost was 24,086 $won/m^3$. The highest cost activity was the yarding 14,557 $won/m^3$ (60.4% of the total cost), followed by the costs of processing 8,461 $won/m^3$ (35.2%) and then by the costs of felling 1,068 $won/m^3$.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.381-384
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• 2006

This study was conducted to selected Korean black raspberry (Rubus coreanus Miq.) for high productivity. The eight major agronomic traits were investigated from 198 clones of the clone bank established in Korea Forest Research Institute, Suwon, Korea. The selection levels based on number of fruit per fructify lateral (NFFL) over 20, and fruit weight (FW) over 1.3g, and yield of individual per fructify lateral (YIFL) over 25g, were applied on 198 clones, resulted in 17 clones selected. The selected superior trees, 17 clones, appeared regional differences for amount of fruiting among 4 different test sites. When number of fruit per fruit petiole (NRFP), fruit weight (FW), yield of individual (YI) and sugar content were satisfied over 20, 1.4g, 6kg and 9.5 brix, respectively, as a select condition, 5 clones were reselected as the superior trees among 17 clones. for 3 years.

• Journal of agriculture & life science
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• v.53 no.5
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• pp.37-49
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• 2019

Environmental conditions are important in increasing the fruit sugar content and productivity of the new cultivar Autumn Sense of Actinidia arguta. We analyzed various soil properties at experimental sites in South Korea. A Pearson's correlation analysis was performed between the soil properties and sugar content or productivity of Autumn Sense. Further, a decision tree was used to determine the optimal soil conditions. The difference in the fruit size, sugar content, and productivity of Autumn Sense across sites was significant, confirming the effects of soil properties. The decision tree analysis showed that a soil C/N ratio of over 11.49 predicted a sugar content of more than 7°Bx at harvest time, and soil electrical capacity below 131.83 µS/cm predicted productivity more than 50 kg/vine at harvest time. Our results present the soil conditions required to increase the sugar content or productivity of Autumn Sense, a new A. arguta cultivar in South Korea.

• Journal of Forest and Environmental Science
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• v.32 no.2
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• pp.189-195
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• 2016

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 $8.6m^3/hr$, followed by delimbing ($5.1m^3/hr$), yarding ($3.5m^3/hr$), and processing ($8.1m^3/hr$). The total cost for the tree-length logging system was $58,446won/m^3$, of which the majority was incurred by the yarding cost at $46,217won/m^3$ (79.3%), whereas the lowest cost was for felling at $2,359won/m^3$ (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.