• Title/Summary/Keyword: clear cutting

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Initial Change of Coleopteran Insect Community Affected by Anthropogenic Disturbances within Pine tree Forest (소나무림내 인위적 간섭에 따른 딱정벌레류 곤충 군집의 초기 변화에 관한 연구)

  • Roh, Seung Jin;Son, Jae Deok;Jeon, Jun Hyoung;Bae, Kwan-Ho;Kim, Hyun-Seop;Park, Sang Wook;Byun, Bong-Kyu
    • Korean Journal of Environment and Ecology
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    • v.29 no.4
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    • pp.539-551
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    • 2015
  • This study was carried out to investigate the changing pattern of forest insect communities in 2013 after harvesting of forest in 2012, and provide a basic data for the method of efficient management for preservation of forest biodiversity. Five types of cutting method in pine tree forest were selected to compare the coleopteran insect communities at Hajang-myeon, Gangwon-do, Korea, in 2013. In this study, we investigated the effects of timber harvest with green-tree retention on coleopteran insects. They were sampled with Lindgren funnel traps for five experimental sites during July to October, 2013. A total of 1,112 individuals in 156 species of 40 families by Lindgren funnel traps. Also, the analysis of coleopteran insects community was performed. Although the difference of density is not prominent among the survey areas in the early stages, it was appeared a tendency to increase in density and abundance of insects in the experimented sites excluding the control areas. Among them, strip clear-cutting area showed a increase of density and abundance in this study.

Monitoring the Restoration of Evergreen Broad-Leaved Forests in the Warm-Temperate Region(III) (난온대 기후대의 상록활엽수림 복원 모니터링(III))

  • Kang, Hyun-Mi;Kang, Ji-Woo;Kim, Ji-Hae;Sung, Chan-Yong;Park, Seok-Gon
    • Korean Journal of Environment and Ecology
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    • v.36 no.1
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    • pp.87-101
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    • 2022
  • This study analyzed changes in the vegetation structure of 16 permanent plots (experimental and control) installed in Wando Arboretum in 1996 to monitor the long-term change process of evergreen broad-leaved forests in warm temperate. Especially, this study discusses the effects of trial treatment (selection cutting and plant introduction), introduced as a restoration technique in 1996, on vegetation development. In communities dominated by Quercus acuta in the canopy (permanent plots 1 through 3), this species's mean important percentage (MIP) decreased, and the evergreen broad-leaved species was introduced from outside increased, likely to change the vegetation structure in the future. The expansion of the evergreen broad-leaved species group was also confirmed in Q. acuta-deciduous broad-leaved forests (permanent plots 5 and 7) and Pinus densifloraforests (permanent plots 9 and 10). In the experimental plots where thinning was carried out, the zoochory (the dispersal of seeds by birds), Cinnamomum yabunikkei, Neolitsea sericea, Machilus thunbergii, etc., and the expansion of the influence of evergreen broad-leaved species were remarkable, so it is considered to have effectively promoted the vegetation development in warm temperate forests. Although evergreen broad-leaved species were planted in the experimental plot to change vegetation structure, it seems the effect on the change was weak due to the small amount of planting. Compared to other vegetation types, the change in the vegetative structure of the pine forest to an evergreen broad-leaved forest was clear due to the decline of P. densiflora and P. thunbergii.

Seed Fructification and Seed Dispersal Characteristics by Harvest Types in Natural Regeneration Sites of Larix kaempferi (일본잎갈나무 천연갱신지의 종자 결실 및 벌채 유형별 종자 비산 특성)

  • Chung, Junmo;Kim, Hyun Seop;Chung, Sanghoon
    • Journal of Korean Society of Forest Science
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    • v.110 no.3
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    • pp.295-307
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    • 2021
  • This study proposed a field-applicable natural regeneration method using natural seeding to afforest a secondary growth forest after felling in Larix kaempferi plantations. In 2016, an experimental site was established usingseed-tree and clear-cutting methods in Gapyeong, Gyeonggi-do, South Korea. Characteristics of seed fructification and inflow in the natural regeneration site were analyzed along with an experimental site in Bonghwa, Gyeongsangbuk-do, which was established in 2014. As a result, the number of seeds per individual tree of V age class L. kaempferi was 690,340 seeds in a good year, with an estimated 13.8 million seeds per ha fruited in natural regeneration sites of L. kaempferi with 25 seed-trees per ha. Seed dispersal began in September and germination rates of seeds dispersed until November were greater than 40%. Reserved seed-tree sites showed the highest amount of seed inflow, followed by the seed-tree site and clear-cut site in descending order. The reserved seed-tree method performed better than other methods for evenly scattering seeds. Therefore, the timing of logging and seedbed generation for natural regeneration of L. kaempferi is estimated to be most effective before September when seeds are purposefully scattered using the reserved seed-tree method as an effective method for uniform seed supply.

Comparison of the Timber Harvesting Productivity and Cost of Single-operation using a Forestry Combi-machine Versus Multi-operation using a Tower-yarder and Processor (타워야더+프로세서 기반의 작업시스템에서 단공정 및 다공정작업의 생산성 및 비용분석)

  • Min-Jae, Cho;Yun-Sung, Choi;Ho-Seong, Mun;Jae-Heun, Oh
    • Journal of Korean Society of Forest Science
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    • v.111 no.4
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    • pp.583-593
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    • 2022
  • The harvesting system in South Korea faces the problems of aging workers and high wages, so it is necessary to improve the operation system and train workers to use high-performance forestry machines. This study compared the effectiveness and costs of yarding and processing operations between a multi-operation system using a tower yarder (HAM300) and a processor (KESLA 20SH) with those of a single-system using a forestry combi-machine. A whole-tree (cable) yarding operation was conducted in the clear-cutting area located at Compartment 15, Gwangneung Experimental Forest, National Institute of Forest Science, and the productivity and cost of multi- and single-system were analyzed. The productivity of the single-system was 1.5 m3/PMH and 1.6 m3/PMH higher than that of the multi- system because the single-system produced 1 log/cycle more than the multi-system in the yarding operation. The cost was approximately 12.1% lower for the single-system (₩36,113/m3) than for the multi-system (₩41,065/m3). The costs of the single-system and multi-system were decreased by maximums of 22.6% and 15.9%, respectively, by decreasing the idle time.

1.6 M SOLAR TELESCOPE IN BIG BEAR - THE NST

  • GOODE PHILIP R.;DENKER CARSTEN.J.;DIDKOVSKY LEONID I.;KUHN J. R.;WANG HAIMIN
    • Journal of The Korean Astronomical Society
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    • v.36 no.spc1
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    • pp.125-133
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    • 2003
  • New Jersey Institute of Technology (NJIT), in collaboration with the University of Hawaii (UH), is upgrading Big Bear Solar Observatory (BBSO) by replacing its principal, 65 cm aperture telescope with a modern, off-axis 1.6 m clear aperture instrument from a 1.7 m blank. The new telescope offers a significant incremental improvement in ground-based infrared and high angular resolution capabilities, and enhances our continuing program to understand photospheric magneto-convection and chromospheric dynamics. These are the drivers for what is broadly called space weather - an important problem, which impacts human technologies and life on earth. This New Solar Telescope (NST) will use the existing BBSO pedestal, pier and observatory building, which will be modified to accept the larger open telescope structure. It will be operated together with our 10 inch (for larger field-of-view vector magnetograms, Ca II K and Ha observations) and Singer-Link (full disk H$\alpha$, Ca II K and white light) synoptic telescopes. The NST optical and software control design will be similar to the existing SOLARC (UH) and the planned Advanced Technology Solar Telescope (ATST) facility led by the National Solar Observatory (NSO) - all three are off-axis designs. The NST will be available to guest observers and will continue BBSO's open data policy. The polishing of the primary will be done in partnership with the University of Arizona Mirror Lab, where their proof-of-concept for figuring 8 m pieces of 20 m nighttime telescopes will be the NST's primary mirror. We plan for the NST's first light in late 2005. This new telescope will be the largest aperture solar telescope, and the largest aperture off-axis telescope, located in one of the best observing sites. It will enable new, cutting edge science. The scientific results will be extremely important to space weather and global climate change research.

A Study on Perceived Problems of and Improvement Measures for Asbestos Abatement Companies in Support of Related Policies (석면 해체 및 제거 업체가 느끼는 관련 제도의 문제점 및 개선방안에 관한 연구)

  • Chang, Jaepil;Rho, Youngman;Jung, Kihyo
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.30 no.1
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    • pp.28-38
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    • 2020
  • Objectives: The purpose of this study is to identify the perceived problems of and suggest improvement measures for asbestos abatement companies in support of asbestos-related systems and policies. Methods: For this study a questionnaire was prepared consisting of current work (two questions), the contribution and necessity of a risk assessment system for asbestos abatement (two questions), and problems with and improvement measures for systems and policies (nine questions). The questionnaires were sent to 2,170 asbestos abatement companies and were returned by 83 companies (return rate = 3.8%). We conducted frequency analysis, ANOVA, and a Chi-squared test at the 5% significance level. Results: Asbestos abatement companies expressed difficulties with complying with wet work (43% of unenrolled managers), negative pressure enclosure (36% of all respondents), and installation and use of decontamination units (26% of all respondents) as stipulated in the relevant regulations. In addition, 43% of the respondents expressed concerns that the expertise of the company was not considered during bidding for asbestos abatement and hoped that an advantage (e.g., bid point) would be given to the upper grades for asbestos risk assessment (38%). Asbestos abatement companies generally rented and used negative pressure devices (including negative pressure recording devices) and suggested that periodic calibration (32%) is needed to ensure the performance of the rented equipment. Finally, the respondents asked for clear definitions for three situations specified in the Occupational Safety and Health Acts: (1) temporarily leaving the asbestos abatement workplace; (2) tasks with less airborne asbestos; and (3) physically breaking or cutting using a machine. Conclusions: The problems and improvement measures identified in this study of asbestos abatement companies can be utilized as fundamental information for the improvement of the systems and policies for safe asbestos abatement.

Site suitability for conifer plantation and a new challenge to utilize deciduous trees

  • NAGASHIMA, Keiko
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.24-24
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    • 2018
  • Degraded plantation forests are increasing because of unfavorable forestry conditions prevailing in Japan, including falling timber prices, increasing operational costs, and aging and declining forestry workforce. To remedy this situation, appropriate management strategy is required. This study introduces the challenges of Odai Town, Mie Prefecture that employed a new management strategy by evaluating site suitability for conifer forests and that proposes a new forest management regime of planting deciduous trees in unsuitable sites. The site suitability for conifer forests was evaluated from two aspects: the natural site conditions and the relationship among site conditions, growth, and damage by Anaglyptus subfasciatus Pic. in Cryptomeria japonica D. Don and Chamaecyparis obtusa Sieb. Et Zucc. forests. By analyzing the relationship among site conditions, growth, and insect damage based on field data obtained in plantation forests, growth evaluation and insect damage evaluation maps were developed. Based on the natural forest investigation, natural site condition maps for C. japonica and C. obtusa were established. Furthermore, by integrating these evaluation maps with the forest road maps showing the accessibility to the forest, the forest management regime for the whole plantation area of Odai Town was established. The forest management regime map indicates the sites suitable for forestry: suitable for long-rotation, short-rotation, and potential sites for short-rotation. The sites unsuitable for forestry were considered to be more suitable for broadleaved forests. Clear-cutting was conducted in a small area and different seral stage saplings (approximately 20 deciduous tree species) suitable to the site conditions were planted in an area of $80-120m^2$ protected by deer-fences. This might establish a forest composed of many species with a multilayer vertical forest structure in a short period. The planted saplings were distributed neither randomly nor uniformly to reflect the natural distribution of trees in the forest. A challenge to develop new products using the deciduous trees has started, such as wood chips for preparing smoked food, essential oil, and deodorizer. As these challenges have just begun, their effects on enhancing sustainable resource management are still being monitored. Even with the challenges, this regime can be of high value as a management strategy to remedy the situation of expansion of degraded forests in Japan.

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Classification of Shopping Information Services on the Web in Korea (국내의 웹 상의 쇼핑 정보 서비스 분류)

  • 강대기;함호상;박상봉
    • The Journal of Society for e-Business Studies
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    • v.4 no.2
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    • pp.1-22
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    • 1999
  • In this paper, we review and classify shopping information services for electronic commerce in Korea. Shopping information services for electronic commerce can be divided into shopping mall information service and product information service. Shopping mall information service simply shows and suggests information on the shopping malls that it has in its data store. But product information service provides information about the items of the shopping malls the service has and therefore gives more powerful and convenient interfaces to users. Cutting-edge product information services can perform online comparison shopping facility, which searches and compares the items what the users want on the reasonable basis of economical criteria, such as price. Books, CDs, and Personal Data Assistant(PDA)s are the products of which the specification is clear enough to be described on the Web. And the comparison of the products by the information service is performed on the basis of "price" of the product item. The approach to design and implement product information service can be divided into two categories. The one is an application of data warehousing mechanism, which stores the product information on the regular basis of time and provide it when the users query over the Web-database gateway. The other approach is a shopping agent mechanism, which stores information on "how to shop" and the shopping agent collects the information of product items just after users query about the product and provide the information in real time or notify them by alerting service. Thirty nine shopping information services are compared and classified in this paper and they are extracted from "Naver" and "Yahoo! Korea". The final result shows that most services are just a simple shopping mall information service in growing stage, product information services with data warehousing are lack in product ontology in middle stage, and that product information services with shopping agent are in early stage.

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Analysis the actual Conditions for the Effect Management on Livelihood Environment Forest Protected Areas (생활환경보호구역의 효율적 산림관리를 위한 실태 분석)

  • Park, Jae Hyeon;Lee, Sang Tae
    • Journal of Korean Society of Forest Science
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    • v.101 no.2
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    • pp.279-285
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    • 2012
  • This study was conducted to offer preliminary data for forest management from March and December 2011. Based on the number of standing trees by DBH classes, it is recommended to practice thinning and pruning to change the current young stand to mature stand. In Livelihood Environment Forest Protected Areas, young (0-10 years or 0-10 cm DBH) and detected trees need to be removed and selected healthy trees need to be heavily tended. Also, selected trees in age 20-30 (20-30 cm DBH class) need to receive concentrated tending. Since Livelihood Environment Forest Protected Areas had been vulnerable for erosion, the diversity of understory layer is low. In order to diversify deciduous trees, it is recommended to introduce new species and thin and prune existing trees. It is not proper to adapt clear cutting in a short time and should be partially regenerated using shelter-wood method or proper tending practices to the Pinus rigida dominanted forest. Tending existing under-story species including Quercus alina, Quercus variabilis, and Quercus serrata would be important.

A Study on the Cooking in 'The Ryuk-Jab-Rok' ("역잡록"의 조리가공에 대한 분석적 고찰)

  • 김성미;이성우
    • Journal of the East Asian Society of Dietary Life
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    • v.3 no.1
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    • pp.12-17
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    • 1993
  • This book is named 'The Ryuk-Jab-Rok' because it was written in the last page of 1820's almanac. This book is written purely in Korean and has not been published yet. This book comprises twenty eight items, among which there are eight items of vegetable preserving method, ten items of Jook preparation methods(a kind of cereal soup), nine items of Pyun-Myun methods(a kind of rice cakes and noodles) and Yak-Bab(a kind of spiced rice). In vegetable preserving method, the eggplant, the cucumber and a songi mushroom were preserved with the drying method., A radish, a sorojangii, and the root of white cabbage were used with the cold temperature preservation. A garlic was dried after salting. The sprouts of DooRub, which were coming in the hot room, were used. In the Jook preparations, there were five animal materials which were lamb, chick, crudian, oyster and abalone. In nine Pyun-Myun methods, Jap-Gua-Sil was illegible because the letters were not clear. Among eight items, the stick rice was used in four cases, the regular rice in two cases. The ground pine nuts, honey and the Chinese date were used most ofter. And the sesame salt and the chestnut were next. The analysis of the terms I this book revealed that 26 items were used for cooking processes. And it also showed us that there were seven kind of cutting procedure and eight kinds of heating procedure. The shapes and size of foods were revealed at only three places in all items. The one-chi(chi ; abut three cm) and three-Ja(Ja ; about thirty cm) which the terms represent the length were revealed twice and once respectively in this book. In the taste description, 'the good', the most common word, was used in seven times, and which was the most frequently introduce case. The measuring unit is hard to revive since the measurements were taken by the container, which were Jong-Ja, Sabal and Tang-gii, then in use. Fifteen kinds of containers and cookers were used for preparing foods. And all of them are now I use.

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