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A Study on the Concentration of Nanoparticles and Heavy Metals in Indoor/Outdoor Air in a University Administrative Public Office (대학교 행정실 실내 외 공기 중 나노입자와 중금속 농도에 관한 연구)

  • Choi, Su-Hyeon;Im, Ji-Young;Park, Hee-Jin;Chung, Eun-Kyung;Kim, Jong-Oh;Son, Bu-Soon
    • Journal of Environmental Health Sciences
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    • v.38 no.6
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    • pp.493-502
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    • 2012
  • Objectives: The purpose of this study is to investigate the mass concentration of nanoparticles and understand the characteristics of elements of heavy metal concentrations within nanoparticles in the air using Micro-Orifice Uniform Deposit Impactor Model-110 (MOUDI-110), based on indoor and outdoor air. Methods: This Study sampled nanoparticles using MOUDI-110 indoors (office) and outdoors at S University in Asan, Korea in order to reveal the concentration of nanoparticles in the air. Sampling continued for nine months (10 times indoors and 14 times outdoors) from March to November 2010. Mass concentrations of nanoparticle and concentrations of heavy metals (Al, Mn, Zn, Ni, Cu, Cr, Pb) were analyzed. Results: Indoors, geometric mean concentration of nanoparticles ranged in size from 0.056 ${\mu}m$ to 0.10 ${\mu}m$ and those of 0.056 ${\mu}m$ or less recorded 0.929 ${\mu}g/m^3$ and 1.002 ${\mu}g/m^3$, respectively. On the other hand, the levels were lower outdoors with 0.819 ${\mu}g/m^3$ and 0.597 ${\mu}g/m^3$. Mann-Whitney U tests showed that the difference between the indoors and the outdoors was statistically meaningful in terms of particles of 0.056 ${\mu}m$ or less (p<0.05) in size. These results are possibly influenced by the use of printers and duplicators as the factor that increased the concentration of nanoparticles. In seasonal concentration distribution, the level was higher during the summer compared to in the autumn. Those of 0.056 ${\mu}m$ or less in size presented a statistically meaningful difference during the summer (p<0.05). These results may be influenced by photochemical event as the factor that makes the levels high. Regarding zinc, among the other heavy metals, the fine particles ranged in size from 0.056 ${\mu}m$ to 0.10 ${\mu}m$ and those of 0.056 ${\mu}m$ or less recorded 1.699 $ng/m^3$ and 1.189 $ng/m^3$ in the outdoors. In the indoors, the levels were lower, with 0.745 $ng/m^3$ and 0.617 $ng/m^3$. Cr and Ni at the size of 0.056 ${\mu}m$ or less, both of which have been known to pose severe health effects, recorded higher concentrations indoors with 0.736 $ng/m^3$ and 0.177 $ng/m^3$, compared to 0.444 $ng/m^3$ and 0.091 $ng/m^3$ outdoors. By season, Zn, Ni, Cu and Pb posted a high level of indoor concentration during the fall. As for Cr, the level of concentration indoors was higher than outdoors both during the summer and the autumn. Conclusion: This study indicates the result of an examination of nano-sized particles and heavy metal concentrations. It will provide useful data for the determination of basic nanoparticle standards in the future.

Limitations on Exclusive Rights of Authors for Library Reprography : A Comparative Examination of the Draft Revision of Korean Copyright Law with the New American Copyright Act of 1976 (저작권법에 준한 도서관봉사에 관한 연구 -미국과 한국의 저자재산권의 제한규정을 중시으로-)

  • 김향신
    • Journal of Korean Library and Information Science Society
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    • v.11
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    • pp.69-99
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    • 1984
  • A dramatic development in the new technology of copying materials has presented us with massive problems on reconciling the conflicts between copyright owners and potential users of copyrighted materials. The adaptation to this changing condition led some countries to revise their copyright laws such as in the U. S. in 1976 and in Korea in 1984 for merging with the international or universal copyright conventions in the future. Copyright defined as exclusive rights given to copyright owners aims to secure a fair return for an author's creative labor and to stimulate artistic creativity for the general public good. The exclusive rights on copyrightable matters, generally for reproduction, preparation of derivative works, public distribution, public performance, and public display, are limited by fair use for scholarship and criticism and by library reproduction for its preservation and interlibrary loan. These limitations on the exclusive rights are concerned with all aspects of library services and cause a great burden on librarian's daily duty to provide balance between the rights of creators and the needs of library patrons. The fair use as one of the limitations on it has been coupled with enormous growth of a new technology and extended from xerography to online database systems. The implementation of the fair use and library reprography in Korean law to the local practices is examined on the basis of the new American copyright act of 1976. Under the draft revision of Korean law, librarians will face many potential problems as summarized below. 1. Because the new provision of 'life time plus 50 years' will tie up substantial bodies of material longer than the old law, until that date librarians would need permissions from the owners and should pay attention to the author's death date. 2. Because the copyright can be sold, distributed, given to the heirs, donated, as a whole or a part, librarians should chase down the heirs and other second owners. In case of a derivative work, this is a real problem. 3. Since a work has its protection from the moment of its creation, the coverage of copyrightable matter would be extended to the published or the unpublished works and librarian's work load would be heavier. Without copyright registration, no one can be certain that a work is in the public domain. Therefore, librarians will need to check with an authority. 4. For implementation of limitations on exclusive rights, fair use and library reproduction for interlibrary loan, there can be no substantial aggregate use and there can be no systematic distribution of multicopies. Therefore, librarians should not substitute reproductions for subscriptions or purchases. 5. For the interlibrary loan by photocopying, librarians should understand the procedure of royalty payment. 6. Compulsory licenses should be understood by librarians. 7. Because the draft revision of Korean law is a reciprocal treaty, librarians should take care of other countries' copyright law to protect foreign authors from Korean law. In order to solve the above problems, some suggestions are presented below. 1. That copyright clearinghouse or central agency as a centralized royalty payment mechanism be established. 2. That the Korean Library Association establish a committee on copyright. 3. That the Korean Library Association propose guidelines for each occasion, e.g. for interlibrary loan, books and periodicals and music, etc. 4. That the Korean government establish a copyright office or an official organization for copyright control other than the copyright committee already organized by the government. 5. That the Korean Library Association establish educational programs on copyright for librarians through seminars or articles written in its magazines. 6. That individual libraries provide librarian's copyright kits. 7. That school libraries distribute subject bibliographies on copyright law to teachers. However, librarians should keep in mind that limitations on exclusive rights are not for an exemption from library reprography but as a convenient access to library resources.

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The Pattern of Pusan Station Shopping District( I ) (부산역(釜山驛) 상점가(商店街)의 패턴( I ))

  • Kim, Won-Kyung
    • Journal of the Korean association of regional geographers
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    • v.5 no.1
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    • pp.25-75
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    • 1999
  • This study concern with the pattern of Pusan Station Shopping District within Pusan City, Korea, one of the third ranked centers within Pusan-the first ranked is CBD, the second is subCBD, the third are Spa Shopping district, Tongnae shopping district, Jobang-Ap shopping district and Yangjeong shopping district. This paper serves as a part of series studies which attempt to clarify the internal structure of Pusan as a whole. Part(I) of this study deals with the pattern of functions including information & culture, business, recreation and retailing. The results are as follows. 1. Pusan Station is one of higher ranked class of central places within Pusan City. But the ratio of dwelling houses is the highest in Pusan Station among the 9 higher ranked central places within Pusan. It means that the residential areas still remain along the maze type of narrower streets inner part of the blocks, especially western belt of this shopping district. 2. Business functions are one of the important criteria which classified the central places within the city and Pusan Station is the first ranked shopping districts in terms of these criteria among the 9 higher ranked central places including CBD within Pusan City. It suggests that Pusan Station is the miniature of the CBD, SubCBD is not the miniature of CBD in the view point of business function. It also means that Pusan Station Shopping District has been developed as a special shopping district or as a special central place. It has not been evolved as a center of the hierarchy of central places within the city by the natural or organic growth. 3. Pusan Station as 'the third space or drinking place' and it's characteristics as a amusement center presents at so called the 'Texas Town'-free tax area- whose customers are mainly U. S. soldiers and foreign sailors. But from the 1990s, this 'Town' changed to 'Russian Town', You can easy to meet many Russians and Russian lettered signboards-not English- along the street. 4. Convenient stores distribute mainly at back streets or along the narrower streets. It means that this kinds of stores have a residential oriented character. And a certain convenient stores locate with almost same distances. It suggests that it's hinterland is limited in nearer neighborhoods.

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육계사료에 CLA와 다른 유지의 첨가.급여가 생산능력에 미치는 영향비교

  • 류명선;김은성;김상호;최형송;정문웅;류경선
    • Proceedings of the Korea Society of Poultry Science Conference
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    • 2001.11a
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    • pp.89-91
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    • 2001
  • Two experiments were conducted to compare the dietary supplemental influence of conjugated linoleic acid(CLA), soybean oil(SBO) and commercial tallow(U) on performance and physiological related factor of broiler chicks. Diets contained CP 21.5, 19% and ME 3,100, 3,100kcal/kg for starting and finishing period. Each three levels(1.0, 2.0, 3.0%) of CLA, SBO, CT were supplemented to basal diets. Five hundred forty and three hundred sixty chicks were applied to 3${\times}$3, 2${\times}$3 factorial design with four replicates in Expt 1 and 2. Weight gain, food intake and feed conversion were weekly examined. Blood cholesterol, ND antibody titer, blood components and were measured at the end of experiment. Metabolizable energy(ME) were measured through the metabolic feeding trial in each oil. ME was 8,542, 9,179, 8,133 kcal/kg in CLA, SBO and CT, respectively. In Expt 1, weight gain of chicks fed 1% dietary oil was significantly lower than other treatments(P<0.05). Feed conversion was significantly improved in SBO supplemental groups of all treatments(P<0.05). In Expt 2, CLA supplements increased weight gain significantly for finishing period(P<0.05) compared to that of other treatments. Feed conversion of chicks fed 2% dietary oil was significantly improved relative that of 3%(P<0.05). HDL of 3% dietary supplemental oil treatments was significantly higher for finishing and starting period in Expt 1 and 2, respectively than other treatments(P<0.05). There were no significantly different M Antibody titer in Expt 1, but showed significance between dietary supplemental oil in Expt 2(P<0.05). CLA content of breast meat was 12.23, 18.74, 25.67 mg/g in 1, 2, and 3% CLA treatments and significantly different between them(P<0.05). As the results of these experiments, feeding CLA tended to improve the weight gain compared In that of other dietary oil, but was not increase the ND antibody titer of broiler chciks. CLA content of breast meat also showed the significance at different level of dietary supplement.

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High-Resolution of Paleoenvironmental Reconstruction and Sea-Level History in Delaware Bay, the East Coast of U.S.A. (미국동부 델라웨어만의 고정밀도 해수면 역사와 고환경 복원)

  • YI, HI-IL;WEHMILLER, JOHN F.
    • 한국해양학회지
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    • v.30 no.4
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    • pp.320-331
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    • 1995
  • The closely spaced cores were analyzed to find detailed reconstruction of paleoenvironments and sealable changes along the Delaware Bay coast. Three areas, Kitts Hummock Beach mars, the St. Jones River marsh, and Bowers marsh near the St. Jones River's mouth, were chosen because these areas are compose of their own geomorphic characteristics and sea-level history. since significance of the stratigraphic correlations was to determine sedimentary fancies and paleoenvironments, multidisciplinary methods such as lithological description, grain-size analysis, organic/inorganic content, water content, mineral composition, botanical analysis, micropaleontological analysis, and /SUP 14/C datings were performed. Five major divisions of marsh environments were recognized in the stratigraphic sections: freshwater marsh, initialfreshwater marsh, slightly brackish marsh, brackish marsh, and salt marsh. Most of the lower part in the stratigraphic sections show freshwater marsh. On the top of this, either brackish marsh or tidal flat/tidal stream was recorded. The pro-Holocene sediments consist of sand, mud, and sandy mud, The pre-Holocene configuration played an important role for developing the Holocene Paleoenvironmental changes. The irregular configuration of the pre-Holocene sediments consist of sand, mud, and sandy mud. The pre-Holocene configuration played an important role for developing the Holocene Paleoenvironmental changes. The irregular configuration of the pre-Holocene surface within short distances permitted the concurrent development of variable environments such as freshwater marsh, brackish marsh or salt marsh at similar elevations. The freshwater marsh in this case was formed in the areas of isolation, so saline-water cannot encroach upon these areas. This complex development of paleoenvironments leads to a difficulty in stratigraphic correlation and interpretation of local relative sea-level changes. The deposition of subsurface sediments was affected by sediment supply, compaction, fluvial activity, biological competition, local tectonics and isostacy, climate and local relative sea-level changes. It was interpreted that the positions in the changes from freshwater environments to brackish environments or ice versa are the turning points of transgressions and regressions. Therefore, multiple transgressions and regressions were identified in the stratigraphic sections of the study area.

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Effect of Moutan Cortex Radicis on gene expression profile of differentiated PC12 rat cells oxidative-stressed with hydrogen peroxide (모단피의 PC12 cell 산화억제 효과 및 neuronal 유전자 발현 profile 분석에 대한 연구)

  • Kim Hyun Hee;Rho Sam Woong;Na Youn Gin;Bae Hyun Su;Shin Min Kyu;Kim Chung Suk;Hong Moo Chang
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.2
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    • pp.529-541
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    • 2003
  • Yukmijihwang-tang has been widely used as an and-aging herbal medicine for hundred years in Asian countries. Numerous studies show that Yukmijihwangtang has anti-oxidative effect both in vivo and in vitro. It has been reported that Moutan Cortex Radicis extract (MCR) was the most effective herb in Yukmijihwang-tang on undifferentiated PC12 cells upon oxidative-stressed with hydrogen peroxide. The purpose of this study is to; 1) evaluate the recovery of neuronal damage by assessing the anti-oxidant effect of MCR on PC12 cells differentiated with nerve growth factor (NGF), 2) identify candidate genes responsible for anti-oxidative effect on differentiated PC12 cells by oligonucleotide chip microarray. PC12 cells, which were differentiated by treating with NGF, were treated without or with hydrogen peroxide in the presence or absence of various concentration of MCR. Cell survival was determined by using MTS assay. Measurement of intracellular reactive oxygen species (ROS) generation was determined using the H2DCFDA assay The viability of cells treated with MCR was significantly recovered from stressed PC12 cell. In addition, wide rage of concentrations of MCR shows dose-dependent inhibitory effect on ROS production in oxidative-stressed cells. Total RNAs of cells without treatment(Control group), only treated with H₂O₂ (stressed group) and treated with both H₂O₂ and of MCR (MCR group) were isolated, and cDNAs was synthesized using oligoT7(dT) primer. The fragmented cRNAs, synthesized from cDNAs, were applied to Affymetrix GeneChip Rat Neurobiology U34 Array. mRNA of Calcium/calmodulin-dependent protein kinase II delta subunit(CaMKII), neuron glucose transporter (GLUT3) and myelin/oligodendrocyte glycoprotein(MOG) were downregulated in Stressed group comparing to Control group. P2X2-5 receptor (P2X2R-5), P2X2-4 receptor (P2X2R-4), c-fos, 25 kDa synaptosomal attachment protein(SNAP-25a) and GLUT3 were downregulated, whereas A2 adenosine receptor (A2AR), cathechol-O-methyltransferase(COMT), glucose transporter 1 (GLUT1), EST223333, heme oxygenase (HO), VGF, UI-R-CO-ja-a-07-0-Ul.s1 and macrophage migration inhibitory factor (MIF) were upregulated in MCA group comparing to Control group. Expression of Putative potassium channel subunit protein (ACK4), P2X2A-5, P2X2A-4, Interferon-gamma inducing factor isoform alpha precursor (IL-18α), EST199031, P2XR, P2X2 purinoceptor isoform e (P2X2R-e), Precursor interleukin 18 (IL-18) were downregulated, whereas MOO, EST223333, GLUT-1, MIF, Neuronatin alpha, UI-R-C0-ja-a-07-0-Ul.s1, A2. adenosine receptor, COMT, neuron-specific enolase (NSE), HO, VGF, A rat novel protein which is expressed with nerve injury (E12625) were upregulated in MCR group comparing to Stressed group. The results suggest that decreased viability and AOS production of PC12 cell by H₂O₂ may be, at lease, mediated by impaired glucose transporter expression. It is implicated that the MCR treatment protect PC12 cell from oxidative stress via following mechanisms; improving glucose transport into the cell, enhancing expression of anti-oxidative genes and protecting from dopamine cytotoxicity by increment of COMT and MIF expression. The list of differentially expressed genes may implicate further insight on the action and mechanism behind the anti-oxidative effects of herbal extract Moutan Cortex Radicis.

Study on the Acceptability and Effectiveness of an Oral Contraceptive Among Iud Drop-outs in Rural Korea

  • Yang, J.M.;Bang, S.;Song, S.W.;Youn, B.B.
    • Journal of Preventive Medicine and Public Health
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    • v.1 no.1
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    • pp.51-66
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    • 1968
  • During a period of about one year(November '66 to December '67), the Yonsei University College of Medicine conducted a field trial of the oral contraceptive(Ovulen) in order to study its acceptability and use-effectiveness among IUD drop-outs in Koyang county. We can summarize the outstanding findings from this investigation as follows; 1. 61.4% of the IUD drop-outs interviewed (911 women) wanted to use the pill. Most of the reasons for not wanting to use it(352 women) pertained to either use of other contraceptive methods(98) or subfecundity(150) following IUD terminations. Only 83 out of 911 women gave reasons related to the difficulty of obtaining pills. Therefore, we can state that most IUD drop-outs if still in need of a contraceptive methods are in favor of trying the pill, and especially so if this method is conveniently available. 2. The 467 women or 37% of those who terminated IUD use actually visited the clinic for medical screening, and only 11 of them or 2.4% were rejected because of pregnancy and other medical reasons such as cervical erosion, myoma, breast mass, etc. 5.5% or 25 of the 456 women who received the first cycle did not take a single pill during the study period. 3. When we defined those 431 women who accepted and took one or more tablets we found that women over age 30, with 4 or more children, and/or with a higher educational level were the best prospects for recruitment. 4. In accuracy of use, about two thirds of the users started taking the pill on the 5 th day as directed for the first three cycles, but the percentages rose sharply to about 80% in later cycles. Tardiness in starting pill use in the first cycle may have occurred partly because they had to return to the clinic monthly to get each new cycle. Among acceptors who did not quit between cycles, 80 to 90% were regular users, missing two or less tablets in each cycle. 5) More than 60% of the users felt well and sometimes lost their pre-acceptance symptoms. especially dysmenorrhea. However, 27.4% (58 women) had side effects attributable to the pill compund as nausea, vomiting, indigestion, breast tenderness, decreased lactation or breakthrough bleeding. 25.0% (53 women) also complained of medical diseases or symptoms not related to the pill, especially during the first three cycles. However, as the confidence and experience of the client and the field workers grew, the incidence of unrelated medical complaints quickly fell to a lower level in the later cycles. 6. As of the end of this study, on December 31, 1967, 49.2% (212 women) had discontinued the use of the pill for medical reasons as well as for the non medical reasons. Only one case terminated use due to a pregnancy after taking pills. The cumulative continuation rates (by the life table method), were 58.9%, 51.9%, 41.0% at the end of 3 months, 6 months and one year, respectively. These rates are lower than in the U.S. studies. Even when we add the retaking group to the first segment, the continuation rate goes up only about 5% above the first segment rates mentioned above. Possible explanations are different dosages, the newerness of the method and the use of only one point for pill distribution in the country together with a monthly return for cycle 1, 2, 3, and 4-6.

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Chronic Renal Failure in Children: A Nationwide Survey in Korea (소아 만성 신부전증의 전국적인 조사연구)

  • Kim, KyoSun;Jeon, Jeong-Sik;Lee, Ik-Jun;Go, Dae-Gyun;Lee, Gyeong-Il;Yun, Hui-Sang;Gu, Ja-Hun;Go, Cheol-U;Jo, Byeong-Su;Kim, Jun-Sik;Son, Chang-Seong;Yu, Gi-Hwan;An, Yeong-Ho
    • Childhood Kidney Diseases
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    • v.4 no.2
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    • pp.92-101
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    • 2000
  • Purpose : We analyzed the demogaphic data md clinical course of Korean children with chronic renal failure (CRF) observed between 1990 and 1999. Patients and Methods : Questionnaires were mailed to all children's hospitals ail through the country. We asked for primary renal disease age and serum creatinine levels at first presentation with CRF and end-stage renal disease (ESRD), and modes of renal replacement therapy (RRT). Results : 401 children (254 boys, 147 girls) with CRF, defined as a permanent increase of serum creatinine above 1.2 mg/dl for at least 3 months or until death, were identified. This represents an incidence of 3.68 per million child population per year. Of these patients, 22$\%$ on younger than 5 years, 28$\%$ 5 to 10 years and 50$\%$ 10 to 15 year. Eight five $\%$ of the patients could be classified with a primary renal disease. The most frequent cause is glomerulonephritis (36$\%$), followed by chronic pyelonephritis (21$\%$), renal hrpo/dylplasia (9$\%$), and hereditary nephropathies (7$\%$). Reflux nephropathy (16$\%$) was the most common single cause of CRF. ESRD was reached in 70$\%$ of all patient. 99.3$\%$ of these started RRT. Hemodialysis (HD, 42$\%$), peritoneal dialysis (PD, 35$\%$) and transplantation (TP, 23$\%$) were performed as the initial mode of RRT. A total of 161 TPs were performed (159 first grafts, 2 second grafts). A total of 32 patients died. The main causes of death were dialysis related complication in HD patients and infections in PD patients. Survival rate on any form of RRT was 88.7$\%$ during the mean follow-up period of 37 months. Conclusion Major efforts should be directed toward earlier diagnosis and treatment of reflux nephropathy to prevent occurrence of Of. Dialysis and TP have now become well accepted forms of treatment in Korean children with ESRD.

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Weed Community Analysis on the Roadways of Kyungnam and Kyungpook Provinces (경남북(慶南北) 도로변(道路邊)에 발생(發生)하는 잡초(雜草)의 생태분석(生態分析))

  • Kim, K.U.;Chung, J.S.;Back, K.W.;Kwon, S.T.;Kim, H.Y.
    • Korean Journal of Weed Science
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    • v.10 no.4
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    • pp.312-327
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    • 1990
  • Weed species investigated on the roadways of Kyungnam and Kyungpook provinces in September, 1989 were 75 species in 31 families and 89 species in 31 families, respectively. Five weed community types were observed on the roadway of Kyungnam province, namely, Kummerowis striata, Humulus japonicum-Artermisia princeps, Digitaria sanguiralis-Eleusine indica, Artermisia princeps-Degitarin sanguinalis and Digilaria sanguinalis-Setaria viridis. In contrast, Kyungpook province had six community types which were Eleusine indica, Humulus japonicum-Commelina communis, Ihgitaria sanguinalis-Eeusine indica, Digitaria sanguinalis-Artermisia princeps, Dzgitaria sanguinalis-Setaria viridis and Setaria viridis community types. Ten major weed species on the roadway of Kyungnam province were Dtgitaria sanguinalis(23.3%). Setaria viradis(8.3%). Edeusine indica(7.3%). Kummerowis striata(6.0%). Humulus japonicum(5.2%), Phaseolus nipponensis(3.5%), Echinochloa crusgalli (2.9%) and Imperata cyliudrica(2.0%). On the roadway of Kyungpook province, ten major weeds were Digitaria sanguinalis (25.4%). Setaria viridis (10.5%). Eleusine indica(9.0%). Humulus japonicum(8.6%). Eragrostis fernsginea(6.5%), Artermisia princeps(3.8%), commelia communis(2.2%), Irexis dentata(1.8%), Equisetum arvense(1.8%) and Kummerowis striata (1.7%).

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Weed Flora of Cultivated Land and Its Surrounding Area in Cheju Island (제주도(濟州道) 농경지(農耕地) 및 그 주변(周邊)에 발생(發生)하는 잡초종(雜草種))

  • Kim, K.U.;Kim, J.H.;Back, K.W.;Lee, I.J.;Kim, S.H.;Choi, Y.S.
    • Korean Journal of Weed Science
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    • v.9 no.3
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    • pp.201-213
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    • 1989
  • About 233 weed species belonging to 54 families mainly occurring in summer were observed in cultivated land and its surrounding area in Cheju Island. The compositae was the most widely occurring family covering 41 weed species, followed by 28 species in gramineae, 14 in labiatae, 13 in leguminasae and 12 in polygonaceae etc.. In terms of the lands classified about 126 species in 39 families were observed in upland ared and 38 species in 20 families occurred in lowland area, 108 species in 36 families in orchard and 214 species in 50 families observed in non-cultivated area. The most dominant weed species in Cheju Island were Portulaca oleracea, Digitaria sanguinalis in both the upland and orchard, Monochoria vaginalis, Cyperus amuricus in lowland, and Digitaria sanguinalis, Artemisia princeps, Partulaca oleracea in non-cultivated land area. There were two communities in upland area, such as Phyllanthus urinaria, Siegesbeckia orinexitalis etc., and Cephalonaplos segetum, Mosla dianthera etc.. The lowland area composed of one major community like Onenanthe javanica, and Eleocharis acicularis. The orchard consisted of the communities of Stellaria aquatics, Viola mandshurica etc., and Justicia procumbens, Varedellia crustacea etc.. The non-cultivated land composed of two major communities like Amplicarpaed edgeworthii, Lactuca indica etc., and Clematis appiiforia, Aster hispidus etc..

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