• Title/Summary/Keyword: introduced

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Distribution of Taraxacum in the Western Area of Kyonggido, Korea (경기도 서부 일원의 민들레속 식물의 분포)

  • 박헌우;박인근
    • The Korean Journal of Ecology
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    • v.20 no.1
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    • pp.1-8
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    • 1997
  • This study was conducted to investigate the distributions of the native and introduced dandelins in the western Kyonggido area and to determine the environmental factor influencing distribution of dandelions. One hundered and thirty seven study sites were randomly selected along roadsides in urban areas, arable lands, apartment areas and industry regions, and vegetation, dandelion's seed characters and soil acidity were sureyed. Throughout the areas the introduced dandelions were more widely distributed than the native ones. The native dandelions were scarcely distributed in the developed areas and roadsides. The introduced dandelions were dominantly distributed in the new environments where soils were alkalized by the trban development, road pavement, and construction of new buildings, while the native ones were mostly distributed in the rural area with weakly acid soil. The seed production of the introduced ones were two times more than that of the native ones. The seed of the introduced ones were lighter than that of the native ones. The introduced ones yield seeds more than four times a year. These results suggested the urbanization and the seed characters to bet the two dominant factors influencing the distribution of dandelions.

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A Vegetation Characteristics of Native and Introduced Kentucky bluegrass Cultivars Seeded on Cut-Slop (자생 및 도입 켄터키 블루그래스 품종의 훼손비탈면 녹화 특성)

  • Jeong, Dae-Young;Shim, Sang-Ryul;Ahn, Byung-Joon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.12 no.1
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    • pp.82-91
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    • 2009
  • Research was initiated to investigate vegetation characteristics of native ('Pureundle' and 'Sewon') and introduced ('Brilliant' and 'Midnight') Kentucky bluegrass (KB, Poa pratensis L.) varieties by soil-seed applying system on a cut-slope in May 17, 2008. There were no statistic differences observed in soil hardness and soil moisture content while significant differences were observed in surface coverage rate, height and disease occurrence in native and introduced KB varieties. The introduced 'Brilliant' KB was highest in the surface coverage rate from the early period of seeding to August 11, 2008. The surface coverage rate of introduced varieties were high when compared to native varieties in their early growth stage. But native varieties reached to equal surface coverage rate with the introduced varieties when three months after seeding. The height of 'Pureundle' and 'Brilliant' KBs were high compared with Midnight and Sewon KBs. 'Pureundle' and 'Brilliant' KBs were damaged by disease whereas there were no disease occurrence in 'Midnight' and 'Sewon' KBs. Probably, the disease occurrence was close related with the height of KBs not with native and introduced KB varieties. These results indicate that the growth of KB on a cut-slope are statistically affected by varieties in early growth stage of this experiment but reach equal rate between native and introduced KB varieties in three months after seeding. This growth characteristics implies the huge potential of native KB varieties seeding for cut-slope vegetation. Considering that native KB varieties are adapted to a environment and have no risk of causing disturbance to the ecosystem compared to the introduced KB varieties, the use of them as native varieties for a cut-slope vegetation can be increased.

A Study on the Utilization of Interior Lanscape Plant through the Investigation of Image -Focused on the Tall Trees- (이미지 조사를 통한 자생수종 활용에 관한 연구 -상층목을 중심으로-)

  • 조현진;방광자;이남현;이영현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.25 no.3
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    • pp.210-221
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    • 1997
  • This study was conducted to investigte the visual preference and response between introduced and native trees for utilization of the south native trees in interior space. 1. The intensity of illumination was below 500lux at 24 buildings of interior spaces surveyed. Generally the temperature was 24~$26^{\circ}C$, and humidity was 60~70%. 2. Total number of introduced tree species were 9 familiar, 16 genus, 18 species, especially palm genus were the largest tree among them at these surveyed interior spaces, but native trees were only 2 species. The introduced tree of 2 to 3m in height was 46 percent, and the case of 1.2 to 2m was 42 percent. 3. The mean of visual preference was the highest at Rhapis excelsa and howeia belmoreana, and followed with Neolitsea sericea, Daphniphllum macropodum, Listsea japonicum. In the mean of visual preference for selected tree groups, native tree was not different as compared with introduced tree. 4. Visual image factor of the native and introduced trees at interior spaces was classified by individual factor and emotional factor. These 2 factors were shown 66.5% total variance. The native tree was strongly recognized on individual factor, as , and introduced tree was also strongly recognized on emotional factor. 5. In the analysis of visual preference and image, a difference between the selected groups of the introduced and native trees were not shown significant, and the introduced trees were similar to the native trees on the visual image. This result was as follow There was an analogy between Cinnamomum camphora, Ligustrum japonicum and Ficus retusa, Ficus benjamina. There is an analogy between Castanopsis cuspidata var. sieboldii, Cinnamomum japonicum and Ficus retusa, Ficus benjamina. There was an analogy between Elaeocarpus sylvestris var. ellipticus, Fatsia japonica and Rhapis excelsa, Howeia belmoreana. There was an analogy between Neolitsea sericea, Daphniphyllum macropo여, Listsea japonica and Rhapis excelsa, Howeia belmoreana. There was an analogy between Elaeocarpus sylvestris var. ellipticus, Fatsia japonica and Dracaena fragranse, Ficus elastica, Monstera deliciosa.

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Analysis Growth Characteristics of the Introduced Species Revegetated on the Highway Cut-slopes (고속도로 비탈면 녹화용 도입초종의 생육특성 분석)

  • 우보명;오구균;김봉년;조영채;전기성
    • Journal of the Korean Institute of Landscape Architecture
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    • v.26 no.1
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    • pp.12-20
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    • 1998
  • This study was carried out from June 1996 to November 1997 to analyze the growth characteristics of the introduced species revegetated on highway cut-slopes. The number of revegetation measures type surveyed were fourteen such as seed-spraying measures, block-sod pitching measures, and hydro-seeding measures with seed-fertilizer-soil materials. The introduced species for revegetation measures were mostly Festuca arundinancea(cool season grass), Eragrostic curvula(warm season grass), Lolium perenne(cool season grass), Dactylis glomerata(cool season grass), Poa pratensia(cool season grass). The species diversity index of the upper part on highway cut-slopes were greater than that of the middle part and lower part. The growth of introduced species was good on north-facing cut-slope than the others and that was flourish in temperate north forest zone. Also, the introduced species seemed to decrease or disappear, while the ratio of native woody and herb species which were in mature stage seemed to increase.

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A Numerical Study on Plastic Shrinkage Cracking of Concrete Slabs (콘크리트 슬래브의 소성수축균열에 대한 해석적 연구)

  • Kwak-Hyo-Gyoung;Ha, Soo-Jun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.11a
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    • pp.785-788
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    • 2005
  • In this paper, the influence of many factors related to the concrete mixture and the weather condition on plastic shrinkage cracking are analyzed through parametric studies using the numerical models introduced in the companion paper. First of all, through a systematic calculation of bleeding, the relationship between the bleeding constants and concrete mixture is proposed on the basis of the experimental data obtained by many researchers. Moreover, an equation, which can directly determine a critical point at which the evaporation and bleeding is balanced, is introduced, and the efficiency of the introduced equation is verified through the correlation study between the obtained results by the introduced equation and those by the rigorous analyses. The introduced equation can effectively be used to predict and to prevent plastic shrinkage cracking without any rigorous analysis and, in advance, to cope with the sudden changes in the concrete mixture and/or weather condition.

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Properties and Repair-Reinforcement of Concrete Introduced Crack (균열이 발생된 콘크리트의 특성 및 보수.보강(구조 및 재료 \circled2))

  • 김영익;윤준노;민정기;김경태;박필우;성찬용
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2000.10a
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    • pp.284-289
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    • 2000
  • This study is performed to evaluate an the crack properties and repair-reinforcement of concrete introduced crack. Materials used are portland cement, coarse aggregate, fine aggregate, unsaturated polyester resin and fly ash. Specimen is used beam of 76${\times}$76${\times}$412mm for measurement of pulse velocity, dynamic modulus of elasticity and bending strength and is introduced crack artificially. The following conclusions are drawn; Pulse velocity, dynamic modulus of elasticity and bending strength of concrete introduced crack is shown the lower 1.24∼11.91%, 3.42∼17.21% and 38.17∼61.0% than that of the control concrete, respectively. Pulse velocity, dynamic modulus of elasticity and bending strength of concrete repaired and reinforced crack is shown the higher 0.5∼2.60%, 1.57∼3.07% and 28.17∼47.25% than that of the concrete introduced crack and the lower than that of the control concrete, respectively.

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An inventory of alien mammals for ecological risk assessment in South Korea (생태계위해성평가 기반 마련을 위한 한국 도입 외래 포유류 목록 구축)

  • Park, Su-Gon;Lee, Do-Hun
    • Korean Journal of Environmental Biology
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    • v.38 no.1
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    • pp.165-178
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    • 2020
  • This study investigated the exotic mammals introduced to Korea to present the basic data necessary for ecological risk assessment and the establishment of an alien species management database. For this purpose, a list of alien mammals introduced to Korea was established by investigating alien mammals introduced for zoo exhibits purposes, alien mammals in breeding environments traded between individuals, and alien mammals introduced into nature. A total of 163 taxa were identified as alien mammals introduced to Korea. There were 139 taxonomic groups of ornamental alien mammals, including 11 orders, 44 families, 129 species and 10 subspecies; 28 taxonomic groups of alien mammals traded between individuals, including five orders and 19 families; and eight taxonomic groups of alien mammals introduced into nature, including four orders, seven families, seven species, and one subspecies. For the effective management of alien mammals introduced to Korea, it is important to collect basic information, such as a list of all species introduced, their populations, and introduced areas. It is also necessary to apply proactive management policies according to the degree of potential risk by preemptively evaluating the ecological risks that may arise from the introduction of alien species into natural ecosystems. For the eight taxonomic groups of Capra hircus, Cervus nippon taiouanus, Felis catus, Myocastor coypus, Oryctolagus cuniculus, Ondatra zibethicus, Ovis aries, and Rattus norvegicus identified to be introduced into the natural ecosystem of Korea, the provision of proliferation control measures at the national level, continuous monitoring of changes in diffusion trends, and immediate response based on the degree of change are required.

Study on Origin of Korea Tobacco by Homogeneity of the Names and Folk Tales in the Tobaccos introduced among Three Countries (삼국에 전래된 담배의 이름과 설화에서 동질성으로 본 한국 담배의 기원 연구)

  • Jeong, Kee-Taeg
    • Journal of the Korean Society of Tobacco Science
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    • v.37 no.1
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    • pp.1-7
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    • 2015
  • The purpose of this study was to establish the origin of Korea tobacco, by homogeneity of the names and folk tales for the tobaccos introduced among three countries. According to the literatures that had written the origin concerning tobacco during the survival period of the Korean author, Korea tobacco came from Japan, for the first time, in 1611~1612. Six year s after the tobacco was introduced, in 1617~1618, tobacco seed also came from Japan. And 10 year safter the tobacco was introduced, in 1621~1622, there was no person that do not smoke. The Korea tobacco name, Dambago(淡婆姑), was the same as Japan tobacco name, Dambago(淡婆姑), but it was not the same as China tobacco name, Tambaku(淡巴菰). The Korea tobacco's folk tale, Dambago(淡婆姑) story, was the same as Japan tobacco's folk tale, Dambago(淡婆姑) story, but it was not the same as China tobacco's folk tale, Tambaku(淡巴菰) or Banhonhyang(返魂香) stories. This finding suggests that Korea tobacco may surely came from Japan, considering homogeneities of the names and the folk tales in the tobaccos introduced among three countries.

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Analysis on productivity and stability of introduced sweet corn hybrids (도입종 단옥수수 교잡종에 대한 생산성 및 안정성 분석)

  • Na, Woong-Hyun;Ha, Ji-Hyoung;Lee, Jae-Heung;Lee, Hee-Bong
    • Korean Journal of Agricultural Science
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    • v.40 no.4
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    • pp.277-280
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    • 2013
  • This study was carried out to compare the productivity and to evaluate the stability for the introduced sweet corn hybrids; Sunnychocolat, 7168Y and Gammiok as a check hybrids. The used materials were planted at Anseong and Daejeon by randomized block design with 3 replications on 21 April, 2013. In productivity of the used hybrid corns, plant and ear height showed comparatively stable as a 183.5 cm to 226.5 cm and 45.8 cm to 80.9 cm, respectively. In yield per 10a, number of ears was higher in Sunnychocolat than check, while Gammiok was very poor in kernel setting length and marketability. Beside, stability of the used hybrids also showed highly in the introduced hybrids than check in the ratio of ear to plant height, tolerance to environmental stress and low lodging. As results above, we thought that these introduced hybrids will be well adapted in domestic cultivation and growth habit as like other hybrid corns.

Studies on Some Characters of Local and Introduced Varieties of Sunflower in Two Different Planting Date (해바라기 국내 재래품종과 도입품종에 대한 소고)

  • Hyun-Ok Choi;Ik-Sang Yu;Kwang-He Kang;Jun-Ho Cho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.21 no.1
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    • pp.132-135
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    • 1976
  • To obtain information on the characters of local and introduced varieties of sunflower, 492 varieties were planted on May 1. and June 15, 1974. Results observed were as flowers; 1) In flowering date, local varieties showed no significant difference between planting date, however introduced varieties were late in the delayed planting date. 2) Local varieties were more sensitive at the response of day length effect than introduced ones. 3) Introduced varieties were recommandable than local in growing them after barley harvest. But local varieties were stable in transplanting.

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