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Sangkyun Han
Division of Forest Sciences, College of Forest and Environmental Sciences, Kangwon National University, 1, Kangwondaehak-gil, Chuncheon-si 24341, Korea

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Review
Published: 12 July 2021 in Forests
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Cable yarding technology remains the most effective operation in steep terrain harvesting systems; however, it has limitations and challenges. Using cable yarders (tractor-, truck-, and excavator-based) to extract tree lengths and whole trees has been common since the late 20th century in South Korea, and cable yarding operations were developed in the late 1800s in the United States and Europe. Machine potential and limitations must be understood to ensure the widespread use of technology, strong cooperation, and optimal selection of machinery size. We reviewed the literature on tower yarder performances from 1990–2021 to determine the alteration of yarders and its productivity pattern and obtained 23 papers; <2 publications per year discussed the determination of cable yarding productivity. We selected independent variables (e.g., silvicultural treatment, harvesting method, and cycle log volume) for cable yarding that would likely affect productivity. Data were analyzed to compare productivities under silvicultural treatment, the harvesting method, and yarding direction and identify the interaction mechanical power (i.e., lifting capacity and machine power), yarding distance, and slope. Cable yarder productivity rates generally depended on the silvicultural treatment, harvesting method, and yarding direction, particularly in clear-cut, tree-length, and uphill yarding operation activities. The lifting capacity, machine power, and slope had no significant correlation with yarders’ productivity, particularly in thinning operations, whereas, in clear-cut productivity, it was influenced by these variables. The results contribute to improving operation activities for cable yarding systems and towards future research directions.

ACS Style

Eunjai Lee; Yunsung Choi; Minjae Cho; Koohyun Cho; Jaeheun Oh; Sangkyun Han; Sangjun Im. A Literature Review on Cable Extraction Practices of South Korea: 1990–2020. Forests 2021, 12, 908 .

AMA Style

Eunjai Lee, Yunsung Choi, Minjae Cho, Koohyun Cho, Jaeheun Oh, Sangkyun Han, Sangjun Im. A Literature Review on Cable Extraction Practices of South Korea: 1990–2020. Forests. 2021; 12 (7):908.

Chicago/Turabian Style

Eunjai Lee; Yunsung Choi; Minjae Cho; Koohyun Cho; Jaeheun Oh; Sangkyun Han; Sangjun Im. 2021. "A Literature Review on Cable Extraction Practices of South Korea: 1990–2020." Forests 12, no. 7: 908.

Journal article
Published: 24 June 2021 in Forests
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On an international comparison basis, Australia’s utilisation of forest residues remains very low. While there are numerous factors contributing to this low utilisation, this is greatly explained by the limited timely and accurate data on availability, quality, and location of residues generated during harvesting operations. This manuscript reports on the development and testing of a new freeware tool called FIELD (Forest Inventory Electronic Live Data), which supports the real-time monitoring and estimation of forestry harvesting residues. As inputs, FIELD uses StanForD pri files and geo-location data extracted from the harvester’s onboard computer in combination with locally developed species-specific allometric equations. Using a case study, this paper describes how FIELD works operationally and illustrates the range of support features that the tool can provide to decision-makers by producing real-time data on the availability, quality, and location of harvesting residues. In addition, it is discussed how the tool can contribute to supporting decisions during forest operations associated with the feasibility of residue utilisation in specific site conditions. Our results show that it is possible to estimate the availability of harvesting residues at geo-located sites dynamically, although further testing of the tool is required for a more accurate estimation and monitoring of harvesting residues.

ACS Style

Heesung Woo; Mauricio Acuna; Byoungkoo Choi; Sang-Kyun Han. FIELD: A Software Tool That Integrates Harvester Data and Allometric Equations for a Dynamic Estimation of Forest Harvesting Residues. Forests 2021, 12, 834 .

AMA Style

Heesung Woo, Mauricio Acuna, Byoungkoo Choi, Sang-Kyun Han. FIELD: A Software Tool That Integrates Harvester Data and Allometric Equations for a Dynamic Estimation of Forest Harvesting Residues. Forests. 2021; 12 (7):834.

Chicago/Turabian Style

Heesung Woo; Mauricio Acuna; Byoungkoo Choi; Sang-Kyun Han. 2021. "FIELD: A Software Tool That Integrates Harvester Data and Allometric Equations for a Dynamic Estimation of Forest Harvesting Residues." Forests 12, no. 7: 834.

Journal article
Published: 28 February 2020 in Korean Journal of Medicinal Crop Science
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Background: This study was conducted to investigate the effects of NaCl concentration on the photosynthetic parameters, chlorophyll fluorescence and growth characteristics of Crepidiastrum sonchifolium. Methods and Results: As treatments, we subjected C. sonchifolium plants to four different concentrations of NaCl (0, 50, 100 and 200 mM). We found that the photosynthetic parameters maximum photosynthesis rate (PN max), net apparent quantum yield (Φ), maximum carboxylation rate (Vcmax), and maximum electron transport rate (Jmax) were significantly reduced at an NaCl concentration greater than 100 mM. In contrast, there was an increase in water-use efficiency with increasing NaCl concentration, although in terms of growth performances, leaf dry weight, root dry weight, stem length, and total dry weight all decreased with increasing NaCl concentration. Furthermore, leakage of electrolytes, as a consequence of cell membrane damage, clearly increased in response to an increase in NaCl concentration. Analysis of the polyphasic elevation of chlorophyll a fluorescence transients (OKJIP) revealed marked decrease in flux ratios (ΦPO, ΨO and ΦEO) and the PIabs, performance index in response to treatment with 200 mM NaCl, thereby reflectings the relatively reduced state of photosystem II. This increase in fluorescence could be due to a reduction in electron transport beyond Q−A . We thus found that the photosynthetic parameters, chlorophyll fluorescence and growth characteristics of C. sonchifolium significantly increased in response to treatment with 200 mM NaCl. Conclusions: Collectively, the findings of this study indicate that C. sonchifolium shows relatively low sensitivity to NaCl stress, although photosynthetic activity was markedly reduced in plants exposed to 200 mM NaCl.

ACS Style

Kyeong Cheol Lee; Sang Kyun Han; Kyeong Kyu Yoon; Hak Bong Lee; Jae Mo Song. Effects of NaCl on the Growth and Physiological Characteristics of Crepidiastrum sonchifolium (Maxim.) Pak & Kawano. Korean Journal of Medicinal Crop Science 2020, 28, 1 -8.

AMA Style

Kyeong Cheol Lee, Sang Kyun Han, Kyeong Kyu Yoon, Hak Bong Lee, Jae Mo Song. Effects of NaCl on the Growth and Physiological Characteristics of Crepidiastrum sonchifolium (Maxim.) Pak & Kawano. Korean Journal of Medicinal Crop Science. 2020; 28 (1):1-8.

Chicago/Turabian Style

Kyeong Cheol Lee; Sang Kyun Han; Kyeong Kyu Yoon; Hak Bong Lee; Jae Mo Song. 2020. "Effects of NaCl on the Growth and Physiological Characteristics of Crepidiastrum sonchifolium (Maxim.) Pak & Kawano." Korean Journal of Medicinal Crop Science 28, no. 1: 1-8.

Journal article
Published: 28 February 2019 in Korean Journal of Medicinal Crop Science
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Background: This study was conducted to investigate the changes in the photosynthetic parameters, chlorophyll content, chlorophyll fluorescence, and growth characteristics of Aruncus dioicus var. kamtschaticus seedlings under different shading treatments. Methods and Results: The shading treatment was regulated with the shading level (non-shaded, 35%, 55%, and 75% shading). Photosynthetic activities, such as net photosynthetic rate, stomatal conductance, stomatal transpiration rate, and performance index on absorption basis ($PI_{ABS}$)were the highest under 35% shading ($4.36{\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$, $54.2mmol\;H_2O{\cdot}m^2{\cdot}s^{-1}$, $0.66mmol\;H_2O{\cdot}m^{-2}{\cdot}s^{-1}$, and 1.3, respectively), and the lowest under 75% shading. This implies that the decrease in net photosynthetic rate may be due to an inability to regulate water and $CO_2$ exchanged through the stomata. Thechlorophylla, b, and a + b contents were increased with elevating shading level and the chlorophyll a/b ratio showed non-significant differences. It was found that the dry weight (leaf, shoot, and whole) was the highest (1.14 g, 0.49 g, and 2.31 g, respectively) under 35% shading and the t/R ratio was the highest under 75% shading. Conclusions: It is concluded that 75% shading exhibited a strong reduction of photosynthetic activity, and 35% shading showed the best conditions for the early growth and cultivation of A. dioicus var. kamtschaticus.

ACS Style

Kyeong Cheol Lee; Sang Kyun Han; Young Hyoo Kwon; Seong Ryeol Jeon; Chang Woo Lee; Dong Jin Seo; Wan Geun Park. Effects of Shading Treatments on Growth and Physiological Characteristics of Aruncus dioicus var. kamtschaticus (Maxim.) H. Hara Seedling. Korean Journal of Medicinal Crop Science 2019, 27, 30 -37.

AMA Style

Kyeong Cheol Lee, Sang Kyun Han, Young Hyoo Kwon, Seong Ryeol Jeon, Chang Woo Lee, Dong Jin Seo, Wan Geun Park. Effects of Shading Treatments on Growth and Physiological Characteristics of Aruncus dioicus var. kamtschaticus (Maxim.) H. Hara Seedling. Korean Journal of Medicinal Crop Science. 2019; 27 (1):30-37.

Chicago/Turabian Style

Kyeong Cheol Lee; Sang Kyun Han; Young Hyoo Kwon; Seong Ryeol Jeon; Chang Woo Lee; Dong Jin Seo; Wan Geun Park. 2019. "Effects of Shading Treatments on Growth and Physiological Characteristics of Aruncus dioicus var. kamtschaticus (Maxim.) H. Hara Seedling." Korean Journal of Medicinal Crop Science 27, no. 1: 30-37.