• Title/Summary/Keyword: random environment

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Epidemiological study of bacterial diseases of cultured olive flounder, Paralichthys olivaceus from 2005 to 2006 in Korea (2005년부터 2006년 사이 우리나라 양식 넙치, Paralichthys olivaceus의 세균성 질병에 대한 역학조사)

  • Cho, Mi-Young;Kim, Myoung-Sug;Kwon , Mun-Gyeong;Jee, Bo-Young;Choi, Hye-Sung;Choi, Dong-Lim;Park, Gyeong-Hyun;Lee, Chang-Hoon;Kim, Jin-Do;Lee, Joo-Seok;Oh, Yun-Kyeong;Lee, Deok-Chan;Park, Shin-Hoo;Park, Myoung-Ae
    • Journal of fish pathology
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    • v.20 no.1
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    • pp.61-70
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    • 2007
  • The epidemiological study was performed to survey the prevalence of bacterial disease of cultured olive flounder, Paralichthys olivaceus from October, 2004 to August, 2006 in Korea. A total of 1,271 of fish samples were collected at random includes fish exhibiting clinical signs of the disease in question. The total 331 samples among 738 cases of infectious diseases were infected with 366 bacteria isolates including Vibrio spp. (42.1%), Streptococcus spp. (16.9%), Edwardsiella tarda (12.3%), Photobacterium damselae subsp. damselae (8.2%), Pseudomonas spp. (2.2%) or others (18.3%). Vibrio spp. and P. damselae subsp. damselae were continually isolated through all seasons but Streptococcus spp. and E. tarda were mainly isolated from May to November. The 206 cases were showed mixed infection with other bacteria (3.6%), parasites (31.4%) or virus (41.7%); Vibrio spp. (n=21), Streptococcus spp. (n=13), Trichodina (n=76), Scutica (n=31), VNNV (n=112), VHSV (n=46).

A study on Heavy metal of soil in the Vicinity of Nanjido (난지도 주변 지역 토양 중금속 오염 특성에 관한 연구)

  • 오현정;김민영;이재영
    • Journal of Soil and Groundwater Environment
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    • v.7 no.3
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    • pp.71-77
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    • 2002
  • This research was carried out from 2001. 4 until 2001. 5 in order to examine the level of soil contamination in the vicinity of Nanjido. The sampling was done at near the Nanjido soil. At the each sampling site we did the sampling at different depth- surface(0~15cm deep), 1m deep, 2m deep, 3m deep. The contamination of Cd, Cu, Pb, As, $Cr^{+6}$, and Hg were tasted and analysed by spectra AA. The examination showed that the average concentration level of the entire sampled soil was Cd, 0.229mg/kg, Cu 8.349mg/kg, Pb : 11.083mg/kg, As : 0.298mg/kg, $Cr^{+6}$ : 0.124mg/kg, and Hg : 0.134mg/kg. The concentration level of at the depth of 0-l5cm, came out to be Cd : 0.305mg/kg, Cu : 8.464mg/kg, Pb : 11 383mg/kg, As : 0.128mg/kg, $Cr^{+6}$ : 0.153mg/kg, and Hg : 0.092mg/kg. It shows that in the cases of Cd and C $r^{+6}$ the average concentration level of the whole sampled soil was about 80% of that of 0-l5cm depth. And as for Hg and As. the average concentration level of the entire sampled soil came out to be approximately twice as high as the sample soil from the depth surface, As for Cu and Pb, there was not much difference between the entire samples average concentration level and the concentration level of surface. It was hard to find much relationship between the depth of each site where sampling was done and the level of concentration, the concentration level of Pb and Cu at the sampling site C and E was quite high, which suggests that it has been affected by the polluted the hyang-dong stream and fill random up waste.

Spatial Distribution of Epilithic Diatom Communities in the Estuary of Korean Peninsula (한반도 하구역 부착돌말류의 공간적 분포)

  • Kim, Ha-Kyung;Cho, In-Hwan;Kim, Young-Hyo;Lee, Min-Hyuk;Kim, Yong-Jae;Won, Du-Hee;Hwang, Su-Ok;Byun, Jung-Hwan;Hwang, Soon-Jin;Kim, Baik-Ho
    • Korean Journal of Ecology and Environment
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    • v.51 no.1
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    • pp.1-15
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    • 2018
  • With land-use (cover) and water quality, the distributional characteristics of epilithic diatom communities were studied with 193 samples from estuaries of Korean peninsula between 2015 and 2016. Of total 394 taxa classified, Nitzschia perminuta (19.6%) and N. inconspicua (14.0%) were the 1st and 2nd dominant species. Using a cluster analysis, the epilithic diatom communities of Korean estuaries were divided into four groups (G1-G4). Ecological characteristics of each group were followed: G1 was located in estuaries of the East Sea, and characterized by high forest land-use and high DO and low nutrients; G2 was the eastern part of the South Sea, and characterized by low turbidity and nutrients; G3 was the western part of the South Sea, and characterized by high agriculture, low electric conductivity and low salinity; G4 was the Yellow Sea, and characterized by high nutrients. The environmental factors having significant correlation with diatom distributions were as follows: TN to G1, turbidity to G2, agriculture to G3, and TP to G4. Moreover, the important factors affecting the occurrence of indicator species were forest land-use for Fragilaria construens var. venter in G1, turbidity for Rhoicosphenia abbreviata in G2, urban land- use and total phosphorus (TP) for Bacillaria paradoxa and Hantzschia amphioxys of G3, and TP and turbidity for N. ovalis and Stephanodiscus invistatus of G4. These results collectively indicate that the distribution of epilithic diatom communities in Korean peninsula was largely effected by water quality and land cover/use.

Vegetation Structure of the Chilseon Valley in the Jirisan National Park (지리산국립공원 칠선계곡지역의 식생구조)

  • Choo, Gab-Cheul;An, Hyun-Cheul;Cho, Hyun-Seo;Kim, Im-Kyu;Park, Eun-Hee;Park, Sam-Bong
    • Korean Journal of Environment and Ecology
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    • v.23 no.1
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    • pp.22-29
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    • 2009
  • To investigate the vegetation structure of mountain valley from Cheonwangbong to Seonneotang, 23 plots($400m^2$) set up with random sampling method were surveyed. Two groups of Abies koreana community, Fraxinus mandshurica-Acer pseudo-sieboldianum community were classified by cluster analysis. Abies koreana was a major woody plant species in the valley area from Cheonwangbong to Mapogpo, and Pinus koraiensis, Acer pseudo-sieboldianum and Sorbus amurensis was partly occupied. High positive correlations was proved between Picea jezoensis and Sorb us amurensis, Taxus cuspidata, Fraxinus sieboldiana, Kalopanax pictus; Betula costata and Betula platyphylla var. japonica, Corn us controversa; Abies koreana and Pinus koraiensis; Stephanandra incisa and Betula ermani, Acer tegmentosum, Prunus sargentii; Acer pseudo-sieboldianum and Betula ermani; Fraxinus mandshurica and Deutzia prunifolia, Acer tschonoskii var. rubripes; Sorbus amurensis and Kalopanax pictus; Betula platyphylla var.japonica and Cornus controversa; Lindera erythrocarpa and Lespedeza maximowiczii, Quercus serrata, Styrax obassia; Lindera obtusi/oba and Abies holophylla; Carpinus laxiflora and Lespedeza maximowiczii; Fraxinus sieboldiana and Acer tschonoskii var. rubripes, Pinus koraiensis, Taxus cuspidata; Acer tschonoskii var. rubripes and Taxus cuspidata; Quercus mongolia and Rhododendron schlippenbachii; Quercus serrata and Styrax obassia, and relatively high negative correlations was proved between Abies koreana and Deutzia prunifolia; Lindera obtusi/oba and Pinus koraiensis. Species diversity(H') of investigated groups was ranged $2.7478{\sim}2.9573$.

The Personal characteristics of university students participating in leisure activities and the impact of their leisure experience on job-seeking Stress (여가활동에 참가하는 대학생들의 개인적 특성과 여가참가경력이 취업스트레스에 미치는 영향)

  • Seo, Soo-Jin
    • Journal of Digital Convergence
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    • v.18 no.10
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    • pp.501-507
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    • 2020
  • The purpose of this study is to identify the personal characteristics of college students participating in leisure activities and the impact of their leisure experience on job-seeking Stress, To achieve this purpose, subjects of this study were sampled 264 university students participant using purposeful sampling method for 2 months from september to october of 2019. Using questionnaires stratified cluster random sampling in university students in C city. Studies have shown that first, looking at gender, women receive more academic stress than men. Second, looking at the results of the school year, the first and fourth graders received more personality stress than the second and third graders. Third, if you look at the results of the major category, it turns out that students in the natural major receive more personality stress than in the social major category. In addition, students in the humanities major are more stressed out about the Family environment stress than in the natural major. Fourth, if you look at the results of the allowance, students who receive 400,000 won to 500,000 won and those who receive 100,000 won to 200,000 won or less are under stress from the family environment stress than those who receive 500,000 won or more. Fifth, if you look at the results of your experience in leisure activities, the more experience you have in leisure Therefore, college students will have to lay the groundwork for self-control through various leisure activities for job stress. activities, the lower your job-seeking Stress.

Forest Structure of the Region from Dongchanggyo to Deogjusa in Woraksan National Park, Korea (월악산국립공원 덕주사-동창교 지역의 산림군집구조)

  • Kim Gab-Tae;Choo Gab-Cheul
    • Korean Journal of Environment and Ecology
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    • v.19 no.2
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    • pp.75-82
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    • 2005
  • To investigate the vegetation structure of the region from Dongchanggyo to Deogjusa in Woraksan National Park, 23 plots$(400m^2)$ set up with random sampling method were surveyed. Three groups Quercus mongolica-pinus densiflora community, Pinus densiflora-Quercus molica community, Mixed Broad-leaved community were classified by cluster analysis. Quercus mongolica, pinus densiflora, Quercus serrata and Fraxinus rhynchophyllai were found as a major woody plant species in Woraksan National Park region. In this area, Quercus mongolica and Pinus densiflora were dominated partially. In the future, the importance percentage of Pinus densiflora might be decreased, but those of Quercus mongolica, Quercus serrata and Fraxinus rhynchophyllai might be increased. High positive correlations were proved between Acer pic tum and Corylus heterophylla, Betula schimidtii; Acer pseudosieboldianum, Cornus controversa ; Stephanandra incisa and Symplocos sawafutagi, Lespedeza maximowixzii ; Symplocos sawafutagi and Fraxinus rhynchophyllai, Lespedeza maximowixzii; Fraxinus rhynchophyllai and Acer pseudosieboldianum, Lespedeza maximowixzii; Quercus variabilis and Fraxinus sieboldiana; Corylus heterophylla, and Rhododendron schlippenbachii; Acer pseudo sieboldianum and Lespedeza maximowixzii, and relatively high negative corrlations was proved between Quercus serrata and Betula schimidtii; Quercus mongolica and Quercus serrata; Corylus heterophylla and Lindera erythrocarpa. Species diversity(H') of investigated groups were ranged from $1.2393\~1.3674$ and it was relatively high compared to those of the ridge area of other national parks.

Vegetation Structure of Mountain Ridge from Miwangjae to Cheonwhangbong in Weolchulsan National Park (월출산국립공원 미왕재-천황봉 구간의 능선부 식생구조)

  • Choo Gab-Cheul;Kim Gab-Tae;Cho Hyun-Seo
    • Korean Journal of Environment and Ecology
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    • v.20 no.2
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    • pp.114-121
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    • 2006
  • To investigate the vegetation structure of mountain ridge from Miwangjae to Cheonwhangbong, 11 plots($2000m^2$) set up with random sampling method were surveyed. Three groups of Quercus mongolica community, Quercus mongolica-Styrax japonica community, Q. mongolica-Pinus densiflora community were classified by cluster analysis. Quercus mongolica was a major woody plant species in the ridge area from Miwangjae to Cheonwhangbong, and Styrax japonica and Pinus densiflora was partly occupied. High positive correlations was proved between Prunus sargentii and Euonymus alatus for. ciliato-dentatus; Quercus serrata and Euonymus alatus; Sorbus alnifolia and Euonymus alatus, Magnolia sieboldii; Acer pseudo-sieboldianum and Euonymus alatus for. ciliato-dentatus; Rhododendron schlippenbachii and Euonymus alatus for. ciliato-dentatandus; Euonymus alatus and Lindera obtusiloba, Castanea crenata, Lindera erythrocarpa; Lespedeza bicolor and Rhododendron schlippenbachii; Castanea crenata and Magnolia sieboldii; Magnolia sieboldii and Lindera erythrocarpa, and relatively high negative correlations was proved between Rhododendron schlippenbachii and Euonymus alatus; Lespedeza bicolor and Castanea crenata; Stephanandra incisa and Magnolia sieboldii; Rhododendron yedoense var. poukhanense and Lindera erythrocarpa; Euonymus alatus for. ciliato-dentatus and Magnolia sieboldii; Fraxinus sieboldiana and Sapium japonicum; Prunus sargentii and Lespedeza maximowiczii; Lespedeza maximowiczii and Lindera erythrocarpa. Species diversity(H') of investigated groups was ranged $2.3225{\sim}2.7721$, and it was relatively low value compared to that of mountain ridge area of other national parks.

Vegetation Structure of Mountain the Region from Wolgagsan to Dogabjae in Weolchulsan National Park Korea (월출산국립공원 월각산-도갑재 지역의 산림 능선부 식생구조)

  • Kim Gab-Tae;Choo Gab-Cheul;Kim Jung-Oh
    • Korean Journal of Environment and Ecology
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    • v.20 no.2
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    • pp.122-129
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    • 2006
  • To investigate the vegetation structure of mountain region from Wolgagsan to Dogabjae, 14 plots($2000m^2$) set up with random sampling method were surveyed. Two groups of Quercus variabilis-Pinus densiflora community, Quercus mongolica-Quercus acutissima community were classified by cluster analysis. Quercus variabilis, Pinus densiflora, Quercus mongolica, Quercus acutissima, Quercus dentata and Quercus serrata were found as a major woody plant species in Weolchulsan National Park region. In this area, Quercus variabilis and Pinus densiflora were dominated partially. In the future, the importance percentage of Pinus densiflora might be decreased, but those of Quercus variabilis, Quercus mongolica, Quercus acutissima and Quercus dentata might be increased. High positive correlations was proved between Quercus variabilis and Pinus rigida; Styrax japonica and Quercus dentata, Quercus acutissima; Pinus rigida and Lindera erythrocarpa, Pinus densiflora; Lindera obtusiloba and Rhododendron mucronulatum; Albizzia julibrissin and Styrax obassia, and relatively high negative correlations was proved between Diospyros kaki and Quercus dentata; Platycarya strobilacea and Lindera erythrocarpa; Symplocos chinensis for. pilosa and Quercus acutissima; Styrax japonica and Styrax obassia; Pinus rigida and Lindera obtusiloba, Fraxinus sieboldiana, Rhododendron mucronulatum; Quercus mongolica and Albizzia julibrissin. Species diversity(H') of investigated groups was ranged $1.2430{\sim}1.2892$.

Phytosociological Community Classification of Mountain Ridge from Guryongryeong to Mt. Yaksu in the Baekdudaegan, Korea (백두대간의 구룡령에서 약수산 마루금의 식생구조 특성에 관한 연구)

  • An, Hyun-Chul;Choo, Gab-Chul;Park, Sam-Bong;Cho, Hyun-Seo;An, Jong-Bin;Park, Jeong-Geun;Ha, Hyoun Woo;Kim, Jin Joong;Kim, Bong-Gyu
    • Korean Journal of Environment and Ecology
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    • v.28 no.6
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    • pp.741-750
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    • 2014
  • To investigate the vegetation structure of mountain ridge from Guryongryeong to Mt. Yaksu, 22 plots ($100m^2$) installed with random sampling method were surveyed. Three groups of Quercus mongolica-Acer pseudosieboldianum community, Q. mongolica community, Cornus controversa-Q. mongolica community were classified by cluster analysis. Q. mongolica was a major woody plant species in the ridge area from Guryongryeong to Yaksusan and Carpinus cordata and C. controversa was partly occupied in some area. High positive correlations showed between Q. mongolica and Symplocos chinensis for. pilosa, Rhododendron schlippenbachii; Tilia amurensis and Tilia mandshurica, Symplocos chinensis for. pilosa; Tilia mandshurica and S. chinensis for. pilosa, R. schlippenbachii; Betula costata and Acer mono; Symplocos chinensis for. pilosa and Rhododendron schlippenbachii, and relatively high negative correlations showed between A. pseudosieboldianum and S. chinensis for. pilosa, R. schlippenbachii. Species diversity(H') of investigated groups were ranged 0.8170~1.1446 and it was lower compared to those of the ridge area of the national parks in Baekdudaegan.

Vegetation Structure of Mountain Ridge from Bukhansansung to Insubong in the Bukhansan National Park, Korea (북한산국립공원 북한산성-인수봉 지역의 산림군집구조)

  • Choo, Gab-Cheul;Um, Tae-Won;Kim, Gab-Tae;Park, Sam-Bong;An, Hyo-Hyeon;Kim, Nam-Ho;Kim, Hee-Jung
    • Korean Journal of Environment and Ecology
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    • v.22 no.2
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    • pp.98-105
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    • 2008
  • To investigate the vegetation structure of the region from Bukhansanseong to Insubong in Bukhansan National park, 16 plost$(2500m^2)$ set up with random sampling method were surveyed. Three groups Quercus mongolica-Mixed Broad leaved community, Pinus densiflora-Quercus mongolica community, Quercus mongolica community was classified (or communities were classified) by cluster analysis. Quercus mongolica were found as a major woody plant species in Bukhansan National park region. High positive correlation were proved between Quercus mongolica and Rhododendron; Quercus mongolica and Rhus tricocarpa; Rhododendron mucronulatum and Rhododendron schlippenbachi; Symplocos chinensis and Rhododendron schlippenbachii; Acer pseudosieboldianum and Magnolia sieboldii, and relatively high negative correlation was proved between Fraxinus rhynchophylla and Rhododendron mucronulatum; Juniperus rigid a and Acer pseudosieboldianum; Styrax obassia and Acer pseudosieboldianum. Species diversity(H') of investigated groups were ranged from $1.236\sim1.319$ and it was relatively high compared to those of the ridge area of other national parks.