• Title/Summary/Keyword: Ha-Do

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Biomass and Energy Content of Quercus mongolica Stands in Gwangyang and Jeju Areas (광양 및 제주 지역 신갈나무림의 바이오매스와 에너지량)

  • Kwon, Ki-Cheol;Lee, Don Koo
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.4
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    • pp.54-65
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    • 2006
  • This study was conducted to examine the biomass and energy content of 60- to 70-year-old Quercus mongolica stand facing northern and southern aspect in Mt. Baekwoon (800 m above sea level), Gwangyang, Jeollanam-do and in Mt. Halla (1,000 m above sea level), Jeju-do. The total biomass was 288.4 ton/ha in northern aspect and 241.9 ton/ha in southern aspect of Mt. Baekwoon while 368.4 ton/ha in northern aspect and 364.3 ton/ha in southern aspect of Mt. Halla. Annual net production was 20.7 ton/ha/yr in northern aspect and 17.7 ton/ha/yr in southern aspect of Mt. Baekwoon while 19.0 ton/ha/yr in northern aspect and 21.2 ton/ha/yr in southern aspect of Mt. Halla. Total biomass and annual net production of Mt. Halla were greater than those of Mt. Baekwoon. The net assimilation rate (NAR) was 5.05 in northern aspect and 4.09 in southern aspect of Mt. Baekwoon, while 4.60 in northern aspect and 3.66 in southern aspect of Mt. Halla, Total energy content was 5,666 GJ/ha in northern aspect and 4,793 GJ/ha in southern aspect of Mt. Baekwoon while 6,550 GJ/ha in northern aspect and 6,435 GJ/ha in southern aspect of Mt. Halla. Annual energy content was 365 GJ/ha/yr in northern aspect and 360 GJ/ha/yr in southern aspect of Mt. Baekwoon while 351 GJ/ha/yr in northern aspect and 347 GJ/ha/yr in southern aspect of Mt. Halla. Annual energy content of Mt. Baekwoon was greater than that of Mt. Halla.

New Estimates of CH4 Emission Scaling Factors by Amount of Rice Straw Applied from Korea Paddy Fields (볏짚 시용에 따른 벼 재배 논에서의 메탄 배출계수 개발에 관한 연구)

  • Ju, Okjung;Won, Tae-Jin;Cho, Kwang-Rae;Choi, Byoung-Rourl;Seo, Jae-Sun;Park, In-Tae;Kim, Gun-Yeob
    • Korean Journal of Environmental Agriculture
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    • v.32 no.3
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    • pp.179-184
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    • 2013
  • BACKGROUND: Accurate estimates of total direct $CH_4$ emissions from croplands on a country scale are important for global budgets of anthropogenic sources of $CH_4$ emissions and for the development of effective mitigation strategies. Methane production resulted by the anaerobic decomposition of organic compounds where $CO_2$ acts as inorganic electron acceptor. This process could be affected by the addition of rice straw, water management and rice variety itself. METHODS AND RESULTS: Rice (Oryza sativa L. Japonica type, var Samkwangbyeo) was cultivated in four plots: (1) Nitrogen-Phosphorus-Potassium (NPK) ($N-P_2O_5-K_2O$:90-45-57 kg/ha); (2) NPK plus 3 Mg/ha rice straw (RS3); (3) NPK plus 5 Mg/ha rice straw (RS5); (4) NPK plus 7 Mg/ha rice straw (RS7) for 3 years (2010-2012) and the rice straw incorporated in fall (Nov.) in Gyeonggi-do Hwaseong-si. Gas samples were collected using the closed static chamber which were installed in each treated plot of $152.9m^2$. According to application of 3, 5, 7 Mg/ha of rice straw, methane emission increased by 46, 101, 190%, respectively, compared to that of the NPK plot. CONCLUSION(S): We obtained a quantitative relationship between $CH_4$ emission and the amount of rice straw applied from rice fields which could be described by polynomial regression of order 2. The emission scaling factor estimated by the relationship were in the range of IPCC GPG (2000).

Simultaneous Maxillo-Mandibular Distraction Osteogenesis in Hemifacial Microsomia: a Case Report (상하악에 동시 다발성 골신장술을 이용한 반안면왜소증의 치험례)

  • Kim, Il-Kyu;Park, Jong-Won;Lee, Eon-Hwa;Yang, Jung-Eun;Chang, Jae-Won;Pyun, Yeong-Hun;Ju, Sang-Hyun;Wang, Boon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.32 no.5
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    • pp.447-453
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    • 2010
  • The hemifacial microsomia is characterized by variable underdevelopment of the craniofacial skeleton, external ear, and facial soft tissues. So, patients with hemifacial microsomia have an occlusal plane canting and malocclusion with facial asymmetry. Distraction osteogenesis (DO) with an intraoral or extraoral device is a technique using tension to generate new bone with gradual bone movement and remodeling. DO has especially been used to correct craniofacial deformities such as a hemifacial microsomia, facial asymmetry, and mandible defect that could not adequately be treated by conventional reconstruction with osteotomies. It has a significant advantage to lengthen soft and hard tissue of underdeveloped site without bone graft and a few complication such as nerve injury or muscle contracture. A 13-years old girl visited our clinic for the chief complaint of facial asymmetry. She had a left hypoplastic maxilla and mandible, occlusal plane canting and malocclusion. We diagnosed hemifacial microsomia and lanned DO to lengthen the affected side. Le Fort I osteotomy, left mandibular ramus and symphysis osteotomy were performed. The internal distraction devices fixed with screw on maxillary and mandibular ramus osteotomy sites. External devices were adapted to lower jaw for DO on symphysis osteotomy site and to upper jaw for rapid maxillary expansion (RME). At 7days after surgery, distraction was started at the rate of 1mm per day for 13days, and after 4months consolidation periods, distraction devices were removed. Simultaneous multiple maxillo-mandibular distraction osteogenesis with RME resulted in a satisfactory success in correcting facial asymmetry as well as occlusal plane canting for our hemifacial microsomia.

Productive Structure and Net Production of Quercus mongolica forest in Mt. Taehwa (Kwangju, Kyonggi-do) (경기도 광주시 태화산 신갈나무림의 생산구조와 생산성)

  • 손석용;권기철;정택상
    • Journal of Korea Foresty Energy
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    • v.21 no.1
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    • pp.76-82
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    • 2002
  • This study was to investigate the productivity of 30-year-old Quercus mongolica forest in the Experimental Forest of Seoul National University located in Mt. Taehwa, Kyonggi-do, Korea. Eight sample trees were selected and cut off. Stem, branches and leaves were weighed respectively with the stratified clipping method, and analyzed for productive struts lure. The allometric regression equations between dry weight of each component(stem, branches, and needles) and D$^2$H were obtained. The results obtained are summarized as follows; (1) Photosynthetic layer of Quercus mongolica was shown at about 4m in height, and maximum needle amount of crown at 10m in height. (2) The total biomass of aboveground was 67.886ton/ha(75.5% from stem, 19.4% from branches and 5.1% from needles). (3) Annual net production of aboveground was 12.76ton/ha/yr, and the ratios of stem, branches and needles to that of aboveground, 44.1%, 28.7% and 27.2%, respectively.

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Occurrence Trends of SU-Herbicide Resistant Weeds in Paddy Fields in Korea (설포닐우레아계 제초제 저항성 논잡초 발생동향)

  • Lee, In-Yong;Won, Tae-Jin;Seo, Young-Ho;Kim, Eun-Jung;Yun, Yeo-Tack;Cho, Seng-Hyun;Kwon, Oh-Do;Kim, Sang-Kuk;Chung, Wan-Gyu;Park, Tae-Seon;Kim, Chang-Seok;Lee, Jeongran;Moon, Byung-Chul;Park, Jae-Eup
    • Weed & Turfgrass Science
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    • v.2 no.3
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    • pp.318-321
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    • 2013
  • National Academy of Agricultural Science and eight province Agricultural Research & Extension Services investigated the occurring area of herbicide resistant weeds in paddy field of Korea. In order to estimate the occurring areas of herbicide resistant weeds, we collected paddy soils randomly from 3,200 sites in 2011 and 2012, and treated 30 kg $ha^{-1}$ of pyrazosulfuron-ethyl+pyriminobac-methyl GR to the paddy soil. 176,870 ha, approximately 22.1% of cultivated area excluding organic and eco-friendly cultivated area, was estimated to be infested by SUherbicide resistant paddy field weeds. Several species of resistant weeds were occurred at Jeonranam-do with 44.3%, followed by 30.5% at Chungchungnam-do, 27.8% at Chungchungbuk-do, and 24.5% at Jeonrabuk-do, respectively. Monochoria vaginalis showed the highest distribution with 57,018 ha, 32.2% followed by Scirpus juncoides, and Lindernia procumbens, respectively.

Resistance to ACCase Inhibitor Cyhalofop-butyl in Echinochloa oryzicola Collected in Gyeongsangnam-do Province of Korea (ACCase 저해 제초제 cyhalofop-butyl에 대한 경남지방 수집종 피의 저항성)

  • Won, Jong Chan;Won, Ok Jae;Ha, Jun;Im, Il-Bin;Kang, Kwang Sik;Pyon, Jong Yeong;Park, Kee Woong;Lee, Jeung Joo
    • Weed & Turfgrass Science
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    • v.7 no.2
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    • pp.166-169
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    • 2018
  • Repeated use of ACCase inhibiting herbicides for a long time has resulted in increases of resistant Echinochloa oryzicola populations in paddy fields in middle west area of Korea. This study aims to investigate current status of herbicide resistant E. oryzicola in Gyeongsangnam-do, in which there is less information about herbicide resistance. For resistance frequency and dose-response study, seeds from 100 individual plants of E. oryzicola in Gyeongsangnam-do were collected and tested with cyhalofop-butyl. Seven percent of plants from Gyeongsangnam-do was resistant at a recommended rate of cyhalofop-butyl. $GR_{50}$ values (herbicide rates required to reduce plant growth 50%) for one representative resistant populations and five susceptible populations were $738g\;a.i.\;ha^{-1}$ and 66-234 (average 147)$g\;a.i.\;ha^{-1}$, respectively, indicating average 5 times difference in resistance. Although lower rate of frequency of herbicide resistance in Gyeongsangnam-do than in Jeollabuk-do, increases of herbicide resistance are expected in this area because of increases of direct seeded rice fields and increases of dependence on a specific herbicide. Therefore, it is necessary to monitor herbicide resistance regularly and conduct integrated herbicide resistance management in this area.

Fusion and (-ko) ha-: Focusing on the [tae]- type expressions (융합 현상과 '(-고) 하-'의 관련성:[대]형 표현의 분석을 중심으로)

  • Chae Hee-Rahk
    • Language and Information
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    • v.10 no.1
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    • pp.1-20
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    • 2006
  • We can distinguish two different groups of 'fusion expressions' depending on whether the verb (-ko) ha- 'do' can be recovered from the contracted expression concerned or not: recoverable and unrecoverable fusion expressions. Many expressions belonging to the former group show alternations between the [da]-type and the [dae]-type: e.g., o-nta-nta and o-ntae-nta '...says... is coming.' On the other hand, some expressions like ka-ntae can only be realized as the [dae]-type. The main purpose of this paper is to account for these [dae]-type expressions. First, we assume that they have an inaudible/invisible quotation $verb\;{\phi}-$, which takes as its complement a verb phrase with a neutral speech-level ending. This quotation verb is derived from the quotation verb ha-. Second, we assume that the quotation $verbs\;{\phi}-$ and ha- have the [j] sound as their stem-final element, which means that these verbs are actually represented as ${\phi}-j-$ and ha-j-, respectively. In this system, the [tae]-type expressions come out naturally from the behavior of the [j] sound. We do not employ any ad hoc phonological rules to derive the [dae]-type expressions from the corresponding [da]-type expressions.

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An Analysis of the Hail Damages to Korean Forests in 2017 by Meteorology, Species and Topography (2017년 우박에 의한 산림피해의 기상, 수종 및 지형 특성 분석)

  • Lim, Jong-Hwan;Kim, Eunsook;Lee, Bora;Kim, Sunhee;Jang, Keunchang
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.19 no.4
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    • pp.280-292
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    • 2017
  • Hail is not a frequently occurring weather event, and there are even fewer reports of hail damages to forest stands. Since the 2000s, an increase in hail incidence has been documented in Europe and the United States. In Korea, severe hails occurred in Jeollanam-do province on May 31 and in Gyeongsangbuk-do province on June 1, 2017. Hail size was ranged from 0.5 to 5.0 cm in diameter in Jeollanam-do, and from 1.5 to 3.0 cm in Gyeongsangbuk-do. This study was aimed to analyze the hail damages to forests by species and topography based on damage-categorized maps created by using drones and aerial photographs, and to analyze relationships of the damages with meteorological factors. The total damaged forest area was 1,163.1ha in Jeollanam-do, and 2,942.3ha in Gyeongsangbuk-do. Among the 'severe' damaged area 326.7ha, 91% was distributed in Jeollanam-do, and concentrated in the city of Hwasun which covers 57.2% of the total 'severe' damaged area. The most heavily damaged species was Korean red pine(Pinus densiflora S. & Z.) followed by P. rigida. Most broad-leaved trees species including oaks were recovered without any dead trees found. Liliodendron tulipifera was the most severely damaged in terms of the rate of 'severe' degree individuals which are needed to be checked whether they will die or be recovered. Cause of the death of pines was considered as the combination of physical damage caused by the hail and long-lasting drought with high air temperature that occurred before and after the hail event. No pathogens and insects were found which might have affected to tree deaths. We suggested a dieback mechanism of the pine trees damaged by hail and drought.