• Title/Summary/Keyword: K-mean cluster analysis

Search Result 303, Processing Time 0.036 seconds

Analysis of Genetic Diversity and Relationships of Korean Native Goat Populations by Microsatellite Markers (MS 표지를 이용한 한국재래염소 집단의 유전적 다양성 및 유연관계 분석)

  • Suh, Sangwon;Byun, Mijeong;Kim, Young-Sin;Kim, Myung-Jick;Choi, Seong-Bok;Ko, Yeoung-Gyu;Kim, Dong-Hun;Lim, Hyun-Tae;Kim, Jae-Hwan
    • Journal of Life Science
    • /
    • v.22 no.11
    • /
    • pp.1493-1499
    • /
    • 2012
  • The level of genetic variation and relationships in three native Korean goat populations (Dangjin, Jangsu, and Tongyeong) as well as the populations of a farm were analyzed, based on 30 microsatellite markers. A total of 277 distinct alleles were observed across the four goat populations, and 102 (36.8%) of these alleles were unique to only one population. The mean observed heterozygosity and polymorphism information content were calculated as 0.461~0.651 and 0.462~0.679, respectively. In the NJ tree constructed based on Nei's $D_A$ genetic distance, the four populations represented four distinct groups. However, the genetic distances between each Korean native goat population and the farm population were two times those among the three native Korean breeds. The genetic structure within the three Korean native goat populations was also investigated. Cluster analysis, using the STRUCTURE software, suggested three clusters. The molecular information of genetic diversity and relationships in this study will be useful for the evaluation, conservation, and utilization of native Korean goat breeds as genetic resources.

Community Structure of Macrobenthic Assemblages near Uljin Marine Ranching Area, East Sea of Korea (울진 바다목장 주변해역 연성기질 조하대에 서식하는 대형저서동물의 군집구조)

  • Hwang, Kangseok;Seo, In-Soo;Choi, Byoung-Mi;Lee, Han Na;Oh, Chul Woong;Kim, Mi Hyang;Choi, Chang Gun;Na, Jong Hun
    • Korean Journal of Environmental Biology
    • /
    • v.32 no.4
    • /
    • pp.286-296
    • /
    • 2014
  • In this study, we investigated the macrobenthic community structure and spatiotemporal variations in Uljin Marine Ranching area, East Sea of Korea. Macrobenthos were collected using a modified van Veen grab sampler from April to September 2013. Total number of species sampled was 345 and mean density was 5,797 ind. $m^{-2}$, both of which were dominated by the polychaetes. The most dominant species were Spiophanes bombyx (53.64%), followed by Magelona sp.1 (6.96%), Cadella semitorta (2.73%), Lumbrineris longifolia (2.16%) and Alvenius ojianus (2.08%). Cluster analysis and nMDS ordination analysis based on the Bray-Curtis similarity identified 2 station groups. The group 1 (station 2, 3, 5, 6, 8 and 9) was characterized by high abundance of the polychaetes Magelona sp.1, Lumbrineris longifolia, Scoloplos armiger, Praxillella affinis, Maldane cristata and the bivalve Alvenius ojianus, with fine sediment above 30m water depth. On the other hand, the group 2 (station 1, 4, 7 and 10) was numerically dominated by the polychaete Lumbrineriopsis sp. and the bivalve Cadella semitorta, with coarse sediment below 5m water depth. Collectively, the macrobenthic community structure showed a distinct spatial trend, which seemed to be related to the water depth and sediment composition.

Spatial distribution of Benthic Polychaetous Communities in Deugryang Bay, Southern Coast of Korea (득량만 저서다모류군집의 공간분포)

  • Kim, Yong-Hyun;Shin, Hyun-Chool
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.7 no.1
    • /
    • pp.20-31
    • /
    • 2002
  • This study was carried out to investigate the composition and the distribution of the benthic polychaetous communities in Deugryang Bay, semi-enclosed bays, on the southern coast of Korea and to deduce temporal changes in community with the comparison of the past studies. In Deugryang Bay, benthic polychaetous community structure was investigated on the base of the samples from 98 stations in 1996 and 1997. The main facies of surface sediment was clayey silt. The overall benthic macrofaunal density was 871 ind./m$^{2}$. The density was highest in the middle part of the bay because Musculus senhousia (Bivalvia) and cumaceans (Crustacea) had their highest densities in some stations. Benthic polychaetes were comprised of 100 species with a mean density of 138 ind./m$^{2}$. Their abundances were higher in the inner bay, in the middle bay, and in the mouth of bay, but poor community structures were established in the whole bay. The dominant species over 1.0 percentage were composed of the total 21 species, and they occupied 78.3% of the total abundance of the benthic polychaetes. The most dominant species was Lumbrineris longifolia (9.3%), followed by Eteone longa (7.3%), Heteromastus filifomis (7.1%), Sternaspis scutata (6.1%). From the cluster analysis, the study area could be divided into three station groups. Station group AI was located in the inner bay and in the shallow coastal region, and its most dominant species was Heteromastus filiformis. At the station group AII in the mouth of bay and in some channel region, its most dominant species were Lumbrineris longifolia and Eteone longa. And at the station group B located in middle part of the bay, the most dominant specis was Sternaspis scutata. In comparison with previous studies, the benthic polychaetous community experienced great change in the view of species number, density and dominant species. The dominant species were Sternaspis scutata and Eteone longa, but their densities declined greatly. Instead of these species, Lumbrineris longifolia and Heteromastus filiformis, known as the potential organic enrichment indicator species, appeared to the new dominant species even if their low densities. These facts mean that Deugryang Bay was maintained yet as little organic enriched area compared to other bays on the coast of Korea, but needed some caution of marine environmental management.

Spatial Distribution of Macrozoobenthos Along the Salinity Gradient and Sedimentary Environment in the Watancheon Estuary, Beobseongpo, Southwest Coast of Korea (법성포 와탄천 하구역의 염분과 퇴적환경에 따른 대형저서동물의 공간분포)

  • Hong, Jae-Sang;Lim, Hyun-Sig
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.7 no.1
    • /
    • pp.8-19
    • /
    • 2002
  • Spatial distribution pattern of macrozoobenthos was studied along the salinity gradient and sedimentary environment in the Watancheon estuary, Beobseongpo, southwest coast of Korea. Ten stations were set from the mouth towards the head of estuary. Three replicate sediment samples were taken using a van Veen grab (surface area $0.1m^{2}$) at each station between June 1998 and January 1999. A total of 114 species were collected during the study period and they are composed of 44 species of polychaetes (39%), 34 of crustaceans (30%), 24 of molluscs (21%) and 12 of miscellaneous. The former two taxa together accounted for 69% in the total number of species. The mean density was 3,053 ind./m$^{2}$, comprising 2,536 ind./m$^{2}$ from polychaetes (83%) and 439 ind./m$^{2}$, crustaceans (14%). Moreover, the mean biomass was 58.23 gwwt./m$^{2}$, consisting of 29.56 gwwt./m$^{2}$ from polychaetes (51%), 23.38 gwwt./m$^{2}$, molluscs (40%). A spionid polychaete Minuspio japonica, two corophiid amphipods Grandidierella japonica and Corophium sinense, a bivalve Potamocorbula amurensis were major dominants at the head of estuary where the salinity was relatively lower compared with contiguous sites. The distributions of M. japonica and G. japonica were significantly related to the salinity and sediment environment, respectively, whereas C. sinense and P, amurensis showed no significance. The nereid polychaete, Hediste japonica, also predominated at the head of the estuary where bottom salinity was relatively low. Species diversity was high at the mouth area whereas low diversity and few species number were seen at the stations in the head of the estuary, influenced by freshwater and sandy sediment. Based on the cluster analysis, the macrobenthic community was classified into four station groups from head (station group A) toward mouth (group D) in the study area. The number of species and abundance between station group B and C were significantly different. And the abundance of between two neighboring station groups (station group A and B, B and C, C and D) was also different. These results suggested that the spatial distribution pattern of macrobenthos in this estuary seemed mainly related to gradients in bottom salinity and sediment grain size among environmental factors.

Community Structure of Subtidal Macrobenthos in Hampyung Bay during Autumn in 1997, Southwest Coast of Korea (한국 서남해역 함평만 조하대의 가을철 저서동물 군집구조)

  • LIM Hyun-Sig;CHOI Jin-Woo
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.34 no.4
    • /
    • pp.327-339
    • /
    • 2001
  • Community structure of macrobenthos was studied at forty one stations of Hampyung Bay, southwest coast of Korea. Three replicate sediment samples were taken at each station in October 1997, using a van Veen grab (surface area $0.1\;m^2$). The types of surface sediment in the sampling area were muddy sandy gravel between bay mouth and bay proper, and gravelly sandy mud between bay proper and inner bay stations. The particulate organic carbon content in the surface sediment was $0.23\sim0.69\%\;(0.44\pm0.10\%)$. A total of 168 species collected during the study period is composed of 58 of polychaetes, 54 of crustaceans, 34 of molluscs and 22 of miscellaneous. The former two taxa together were accounted for $66.6\%$ of the total number of species. The mean density was $1,168 ind./m^2$, comprising $684 ind./m^2$of molluscs ($58.6\%$), $381 ind./m^2$of polychaetes ($32.6\%$), and $90 ind./m^2$of crustaceans ($13.2\%$). The mean biomass was $358.65 g/m^2$, which is consisted of $302.97 g/m^2$of molluscs ($84.5\%$), $24.20 g/m^2$of echinoderms ($6.7\%$), and $19.16 g/m^2$of crustaceans ($5.4\%$). Major dominant species at the inner stations of the study area was Ruditapes philippinarum with a density of $520ind./m^2$($44.5\%$), and Lumbrineris lontifolia with $183ind./m^2$($15.7\%$), while that at bay mouth stations Pitar indecoroides with $56ind./m^2$. Reticunassa festiva, Heteromastus sp., Praxillella affinis, Chone sp. and Tharyx sp. were at from all stations. Based on the cluster analysis, the macrobenthic community in the bay was classified into five station groups depending on sediment types: Group A, a high gravel content in the sediment; Group B, stations with high mud content from bay mouth to bay proper, Group C, stations with fine and poorly sorted sediment from bay proper to the inner bay. The distribution pattern of the number of species, abundance and biomass is discussed in relation to environmental variables.

  • PDF

Development of the Korean Form of Zung's Self-Rating Anxiety Scale (한국형 자가평가 불안척도의 개발)

  • Lee, Jung-Hoon
    • Journal of Yeungnam Medical Science
    • /
    • v.13 no.2
    • /
    • pp.279-294
    • /
    • 1996
  • This study was carried out to develop a Korean language version of Zung's self-rating anxiety scale(SAS) from august, 1994 to September, 1996. The subjects consisted of 205 normal control subjects from the general population group, and 97 subjects with anxiety disorders. These 97 subjects were chosen from a group by the structured clinical interview for DSM-IV of in patients and out patients. Both normal control subjects and anxiety disorder subjects were drawn utilizing a cluster of sampling methods. In order to analyze the data on anxiety scores, Pearson's product moment correlation coefficient method was carried out, as well as reliability, factor analysis and discriminant function analysis, utilizing the SPSS/PC+ program. The results obtained were as follows: The mean average of the total anxiety scores were 32.36 + 6.35 for the normal control subjects and 50.53 + 7.67 for anxiety disorder subjects. Test-retest reliability(coefficient r=0.98, p < 0.001), and internal consistency(coefficient r=0.96, p < 0.001) were satisfactory. Factor analysis using oblique technique rotation yielded four factors. The normal control subjects scored higher concerning the symptoms such as sweating, restlessness, apprehension, insomnia and dyspnea, and lower for faintness, mental disintegration, paresthesia, dizziness and tremor. On the other hand, for the anxiety disorders, apprehension, restlessness, sweating, dyspnea and insomnia scored higher, and lower for faintness, paresthesia, nightmare, dizziness and tremor.

  • PDF

Community Structure and Health Assessment of Macrobenthic Assemblages at Spring and Summer in Geoje-Hansan Bay, Southern Coast of Korea (거제한산만에 서식하는 대형저서동물의 춘계와 하계의 군집구조 및 건강도 평가)

  • Jung, Rae Hong;Seo, In-Soo;Choi, Byoung-Mi;Choi, Minkyu;Yoon, Sang-Pil;Park, Sang Rul;Na, Jong Hun;Yun, Jae Seong
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.22 no.1
    • /
    • pp.27-41
    • /
    • 2016
  • This study was performed to investigate the community structure and health assessment of macrobenthic assemblages in Geoje-Hansan Bay, Southern Coast of Korea. Macrobenthos were collected by van Veen grab sampler at May (spring) and August (summer) 2013. The total species number and mean density were 300 species $7.6m^{-2}$ and $1,994ind.\;m^{-2}$, respectively. The major dominant species were the polychaetes Lumbrineris longifolia ($299{\pm}164ind.\;m^{-2}$), Aphelochaeta monilaris ($100{\pm}57ind.\;m^{-2}$), the bivalve Musculista senhousia ($91{\pm}96ind.\;m^{-2}$) and the polychaete Praxillella affinis ($80{\pm}66ind.\;m^{-2}$). From the community statistics [cluster analysis and nonmetric multidimentional scaling (NMDS) ordination], the macrobenthic community was distinguished into two groups of inner bay (farming ground of near Sandal Island) and channel station(from Hansan Island to Chubong Island) group. In this study, the ecological status was assessed by four biotic indices Shannon's H', the ATZI Marine Biotic Index (AMBI), multivariate-AMBI (M-AMBI) and the Environment Conservation Index (ECI). The ecological status of the macrobenthic community in Geoje-Hansan Bay were poorer in the inner bay station than in the channel station. The results of the present study showed that three biotic indices (Shannon's H', M-AMBI and ECI) were valid as an index for evaluating the ecological status than the AMBI.

Community Structure and Health Assessment of Macrobenthic Assemblages at Spring and Summer in Garorim Bay, West Coast of Korea (가로림만에 서식하는 대형저서동물의 춘계와 하계의 군집구조 및 건강도 평가)

  • Jung, Rae-Hong;Seo, In-Soo;Lee, Won-Chan;Kim, Hyung-Chul;Kim, Jeong-Bae;Choi, Byoung-Mi;Yun, Jae-Seong;Na, Jong-Hun
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.20 no.5
    • /
    • pp.491-503
    • /
    • 2014
  • This study was performed to investigate the community structure and health assessment of macrobenthic assemblages in Garorim Bay, West Coast of Korea. Macrobenthos were collected by van Veen grab sampler at May(spring) and July(summer) 2012. A total of 247 species occurred and mean density was $1,625\;ind.\;m^{-2}$, both of which were dominated by annelid polychaetes(120 species and $1,241m^{-2}$). Dominant species were the polychaetes Ampharete arctica, Lumbrineris longifolia, Mediomastus californiensis and Euclymene oerstedi, with a density of 445(${\pm}1,837\;ind.\;m^{-2}$), 103(${\pm}148\;ind.\;m^{-2}$), 55(${\pm}83\;ind.\;m^{-2}$) and 50(${\pm}104\;ind.\;m^{-2}$), respectively. The study area was divided into 3 station group based on the cluster analysis and nMDS ordination. These assemblage were : 1)the group 1 and 2 were associated with coarse sediment dominated stations and 2)the group 3 was connected with a mixed and fine sediment dominated stations group. The BPI and AMBI index were applied to assess the benthic ecological status. The ecological status of the Garorim Bay was "good status(slightly polluted)" to "high status(normal)" at most sampling stations during spring and summer. In conclusion, the two marine biotic index calculated shown that the Garorim Bay had a good ecological status.

Genetic Diversity and Relationship by SSR Markers of Korean Soybean Cultivars (한국 콩 육성품종의 SSR마커에 의한 유전적 다양성과 유연관계)

  • Kim Seong-Hun;Jung Jong-Wook;Moon Jung-Kyung;Woo Sun-Hee;Cho Yong-Gu;Jong Seung-Keun;Kim Hong-Sig
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.51 no.3
    • /
    • pp.248-258
    • /
    • 2006
  • Genetic diversity of 91 Korean soybean cultivars was assessed with 20 simple sequence repeat (SSR). Twenty SSR loci generated a total of 149 alleles. The number of alleles for each SSR locus ranged from 3 to 15 with a mean of 7.5 alleles. Genetic diversity estimated by PIC value of 91 cultivars was ranged from 0.424 to 0.905 with an average of 0.711. Cluster analysis based on Nei's genetic distances classified 91 soybean cultivars except Geomjeongkong 4 into 7 groups. The majority groups were I, IV, and VI which included 26, 24, and 18 cultivars, respectively. Obvious differences in genetic diversity appeared to be related with the released periods of cultivars and utilization type of cultivars, but not with breeding sites. Cultivars released in 1970's and in 1990's showed the lowest and the highest genetic diversities with 0.576 and 0.706, respectively. Soybean cultivars for vegetable and early maturity showed the lowest genetic diversity with 0.514, while those for soy sauce and tofu showed the highest genetic diversity with 0.691. Genetic distance between soybean cultivar groups developed before 1969 and during 1970's was the nearest, while genetic distance between those developed in 1970's and 1990's was the furthest. Cultivar group for vegetable and early maturity showed the furthest genetic distance with cultivar group for soy sauce and tofu, while it showed the nearest genetic distance with cultivar group for cooking with rice. Genetic distance was greater between soybean cultivar groups developed in Suwon and Iksan than between those developed in Milyang and Iksan.

The Community Structure of Macrobenthic Assemblages in the Taehwa River Estuary, Ulsan, Korea (울산 태화강 하구역에 서식하는 대형저서동물의 군집구조)

  • Kim, Hyung-Chul;Choi, Byoung-Mi;Jung, Rae-Hong;Lee, Won-Chan;Yun, Jae-Seong;Seo, In-Soo
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.22 no.6
    • /
    • pp.694-707
    • /
    • 2016
  • This study investigated the community structure of macrobenthic assemblages in the Taehwa River Estuary, Ulsan, Korea. Macrobenthos were collected with a Van Veen Grab Sampler during February and November 2012. The total species number and mean density were $176species/9.6m^2$ and $1,992inds./m^2$, respectively. Polychaetes were the most dominant faunal group in terms of species (91 species) and abundance ($1,463inds./m^2$). The major dominant species were polychaetes Minuspio japonica ($609{\pm}1,221inds./m^2$), Hediste japonica ($174{\pm}318inds./m^2$), Tharyx sp.1 ($106{\pm}283inds/m^2$), Lumbrineris longifolia ($79{\pm}207inds./m^2$), bivalve Theora fragilis ($114{\pm}272inds./m^2$) and amphipod Grandidierella japonica ($88{\pm}223inds./m^2$). Based on community statistics (cluster analysis and non-metric multidimensional scaling (nMDS) ordination), the macrobenthic community was divided into three station groups. Group I(freshwater dominated stations 2-6 with coarse sediment) was characterized by a high abundance of polychaetes Minuspio japonica, Hediste japonica, Capitella capitata, Pseudopolydora kempi, amphipods Grandidierella japonica and Apocorophium acutum. Group II (ecotone, stations 7-9 with mixed sediment) was numerically dominated by bivalve Theora fragilis, polychaetes Cirriformia tentaculata, Tharyx sp.1, Lumbrineris longifolia and Chaetozone sp. Finally, Group III (seawater dominated stations 10-12 with fine sediment) was characterized by a high density of polychaete Magelona japonica. These results showed that changes in salinity gradient and sedimentary characteristics were the main factors behind spatial changes in the macrobenthic communities of the Taehwa River Estuary.