• Title/Summary/Keyword: community classification

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Analysis for the relationship of environmental factors and vegetation structure at natural streamside valley and riparian forest in South Korea

  • Cho, Kyu-Tae;Jang, Rae-Ha;You, Young-Han
    • Journal of Ecology and Environment
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    • v.38 no.4
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    • pp.405-413
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    • 2015
  • We classified the streamside plant community by phyto-sociological method and analyzed the relationship between environment factors and vegetation structure by using the classification and ordination method. We found that twenty one plant communities were classified according to dominant species at the natural streamside valley forest with surveying the 65 quadrats (10 m × 10 m). From the survey results, the hardwood plant communities were classified as streamside valley forest and the softwood plant communities as riparian forest according to the degree of flooding. The valley forest had a distribution of 17 plant communities which was 65% (42 quadrats) of 65 quadrats: Maackia amurensis community, Betula davurica community, Quercus variabilis community, Pinus densiflora community, Q. serrata community, Prunus sargentii community, and Meliosma oldhamii community etc. The riparian forest had a distribution of four plant communities which was 35% (23 quadrats) of 65 quadrats: Salix koreensis community, S. rorida community, S. purpurea var. japonica community, and S. glandulosa community, etc. From the two-way indicator species analysis (TWINSPAN) analysis, we found indicator species Oplismenus undulatifolius and Lindera obtusiloba for the streamside valley forest and Humulus japonicus, Phragmites japonica, and S. koreensis for the riparian forest. From the results of the canonical correspondence analysis (CCA), coordinates, altitude, and stream structure showed low correlation to the distribution of the plant community. Therefore, it seemed that valley forest and riparian forest were distinguished by the stream gradient and waterway width which determined by the stream water level.

A Study on Community Classification of Forest Vegetation in Mt. Naeyeon (內延山 一帶 森林植生의 群落分類에 關한 硏究)

  • 윤충원;이병천
    • The Korean Journal of Ecology
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    • v.25 no.2
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    • pp.83-91
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    • 2002
  • This study was carried out to classify forest vegetation of the Mt. Naeyeon with phytosociological analysis of ZM school and to explain ordination of communities with CCA. The research sites were located between the northern part of Pohang-si area and the southern part of Yeongdeok-gun area. The 70 plots consisted of 253 species were investigated. The forest vegetation was classified into Quercus mongolica community, Q. variabilis community, Pinus densiflora community, Carpinus laxiflora community and Zelkova serrata community. Q. mongolica community was divided into 2 groups such asRhododendron schlippenbachii group and Euonymus oxyphyllus group and Q. variabilis community was divided into 3 groups such as Syneilesis palmata group, Lespedeza × tomentilla group and Tilia mandshurica group, and Z. serrata community was divided into 2 groups such as Carpinus cordata group and Diospyros lotus group. According to the results of CCA ordination, Q. mongolica community showed high positive correlation to altitutde and topography, whereas it showed negative correlation to bare rock. Buck Z. serrata community showed the opposite tendency to Q. mongolica community. Altitude was considered as the most important factor among 5 environmental variables in the correlation with axes.

Suggestions for Setting on Period of Epidemic Waves in COVID-19 Epidemic of South Korea (한국 코로나19 유행기에 대한 제안)

  • Lee, Moo-Sik
    • Journal of agricultural medicine and community health
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    • v.47 no.2
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    • pp.61-66
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    • 2022
  • Objectives: In the epidemiology of communicable diseases, the term epidemic period, also referred to as "wave" is often used in the general and academic milieu. A wave refers to a natural pattern of increase in the number of sick individuals, a defined peak, and then a decline in the number of cases. It implies a pattern of peaks and valleys after a particular peak is taken. The idea of epidemic waves is a useful tool for predicting the course as well as helping to accurately describe an epidemic. However, in many domestic and foreign news as well as in various research results in Korea, most of the reports either had no standard, were inaccurate, had a questionable classification of the period of the epidemic, or the basis for classification of a given wave was not presented. Methods: The author reviewed and organized related literature with epidemic wave. The author made several suggestions of an epidemic wave as follows. Results: To start with, it should be based on the number of incident cases in consideration of the size of the outbreak, then the period from the bottom to the peak and then reaching the next bottom; also, the period over a certain scale based on the number of incident cases; and the period according to the change in the major infection type (mutation-dominant species). In addition, according to the period of change in the vaccination rate (formation of herd immunity), as well as the content and duration of the intervention, that is, classification according to the applied quarantine stage. Furthermore, the classification of epidemic periods by the time-dependent reproduction number or time-varying reproduction number (Rt), and lastly the application of mathematical methodology. Conclusions: Therefore, classifying the epidemic period into generally known and accepted time frames is considered to be a very important task for future research analysis and development of intervention strategies.

An Analysis of the Vegetation-Environment Relationships in Major Hardwood Communities by TWINSPAN and CANOCO (TWINSPAN 과 CANOCO 에 의한 주요 활엽수 군집과 환경의 상호관계 분석)

  • Song, Ho-Kyung;Kyu-Kwan Jang;Ki-Won Kwon
    • The Korean Journal of Ecology
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    • v.18 no.1
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    • pp.99-108
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    • 1995
  • Deciduous hardwood communities were ecologically analyzed in order to determine their distributional characteristics. The quadrats were sampled in Mt. Chiri, Mt. Deokyu, Mt. Kyeryong, Mt. Sokri, and Mt. Jungwang, and their environmental factors including topographical features as well as soil properties were investigated. The computer program TWINSPAN and CANOCO were used to elucidate the relationship between environmental factors and species composition. In the relations of communities and environmental factors, the optimal ecological habitats of Carpinus tschonoskii community could be the sites at low latitudes such as the regions of southern part of Korea in which total nitrogen and organic matters are rich, while those of Fraxinus mandshurica community, Acer mono community, and Betula costata community could be the sites which are wet and have high total nitrogen and organic matters in soil. The quercus mongolica community is distributed widely throughout Korea, and its ecological habitats could be the sites which have high soil nutrient and moderate soil moisture in central and northern parts of Korea, while those of Quercus variabilis community could be the sites which is dry and have high Mg and C.E.C. value.

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Community Composition and Adapted Environment of Sundew (Drosera rotundifolia) in Koppler Moor, Austria (Austria Koppler Moor에 서식하는 끈끈이주걱(Drosera rotundifolia)의 군란형성과 적응환경)

  • 이종운
    • Journal of Life Science
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    • v.10 no.2
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    • pp.169-176
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    • 2000
  • At Koppl area, undamaged natural habitat of sundew, I have analysed interspecific affinities and community composition through mathematical method and important environmental factors. Interspecific affinities of the species with frequency of more than 5% in vegetation table were analysed through chi-square test and showed obvious group of Drosera rotundifolia, Vaccinium uliginosum, Calluna vulgaris, Eriophorum angustifolium and 21 species. The result of ordination anlysis using DECORANA of VESPAN II showed eigenvalue of 0.6047 for axis I, 0.2024 for axis II and 0.0763 for axis Ⅲ. And it divided into 4 groups of quadrat number 1-5 for Sphagnum squarrosum-community, 6-10 for Crepis paludosa-community. 11-25 for Carex panicea-community and 26-35 for Scorpidium scorpioides-community. By the classification using TWINSPAN, the 7 areas divided into 2 groups of 1-10 and 11-35 at first level of division with high eigenvalue of 0.588 and indicator was Sphagnum squarrosum. At second level of division it divided into 4 groups as the results of DECORANA with eigenvalues of 0.268 and 0.423 and indicators were Pinguicula vulgaris and Scorpidium scorpioides. Microclimatic environment of studied area was low in temperature and high in humidity and soil environment showed high in field moisture capacity, acid, high organic matter content, low NO3 and K2O content, compare to normal soil, and high ground water level.

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The Analysis of Forest Ecosystem in Wangpicheon Area, Uljin-gun, Gyeongsangbuk-do, Korea -With a Special Reference to Vegetation- (울진군 왕피천 주변지역의 산림생태계 분석 -식생분야를 중심으로-)

  • 최송현;김정호
    • Korean Journal of Environment and Ecology
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    • v.17 no.2
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    • pp.153-168
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    • 2003
  • Wangpicheon, which is located in Uljin-Gun, Korea, is threatened with various developments plan recently. To investigate the forest structure, actual vegetation and degree of green naturality(DGN) in Wangpicheon, survey was carried out within about 1km width from the stream. In the analysis of actual vegetation, the forest type around Wangpicheon is differentiated into 26 vegetation ones. In these, six Pinus densiflora - dominated vegetation types are appeared a great many of them. In DGN analysis, 70.8% of total area is covered by DGN 8 and 0.3% of total area is covered by DGN 9. According to the analysis of classification by TWINSPAN, the community was divided by three types of Pinus densiflora community and two types of Quercus spp. community i.e. Quercus mongolica and Q. vuliabitis community. The structure of communities were analyzed using importance percentage, and species and individuals, DBH distribution and similarity analysis were executed.

Bai people (Baizu) and their ancestors in Yunnan, China: A critical study on the "Ethnic History" in PRC (백족(白族)과 '백만(白蠻)' - 『백족간사(白族簡史)』의 백족 계보 구성 비판)

  • Jeong, Myeon
    • Journal of North-East Asian Cultures
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    • v.33
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    • pp.23-49
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    • 2012
  • In this paper, I examined the history of Baizu that the Brief History presented. PRC created Baizu as one the 55 ethnic minority nations, as it "nationalized" all the people living within its territorial boundary. And it constructed the narrative of the "ethnic history" of Baizu, while it constructed the grand narrative of the history of the unified, multinational "zhonghua minzu." There are two major problems in the historical narrative of Baizu, thus constructed. First, the genealogy of the ancestors of Baizu constructed by PRC lacks sufficient historical evidence to prove it. Second, the politically-driven ethnic classification project by PRC produced ethnic minority nation, which does not have their own territory and Baizu was one of them. Because of this, the history of Baizu, who historically lived mixed with other ethnic groups together in Yunnan, cannot help but becoming a part of the larger Yunnan history, rather than constituting a history of an ethnic group. Then, what would be a historically sensible way to write a history of ethnic minorities in Yunnan, who have not transformed themselves into a modern nation? What I would like to suggest is, first, to abandon the construction of the history of Baizu as an ethnic group. I also suggest to distinguish Yunnan from China (zhongguo) as a unit of historical writing, and thus to cut the relationship between the Baizu history and the larger history of the unified, multitethnic "zhonghua minzu." The narrative of the Chinese history (history of Zhongguo), which takes the PRC's current territorial boundary as the unit of historical narrative, lacks historical objectivity. Names for historical communities survive, because they have been used by those who have lived in the communities as well as by other historical communities. Members of a certain historical community occupy distinctive historical space and share common historical experience. And their historical experience is mainly informed by political changes that affected the space that the historical community occupies. If one constructs the history of "Yunnan" as a distinctive historical space and community, which could be distinguished from the historical "China" (zhongguo), one may be able to construct the history of the people of Yunnan in its fullest sense.

Forest Vegetation Classification on Sobaeksan National Park in the Baekdudaegan (백두대간 소백산국립공원의 산림식생유형 분류)

  • Yun, Joo-Wan;Jung, Sung-Cheol;Koo, Gyo-Sang;Lee, Jung-Hyo;Yun, Chung-Weon;Joo, Sung-Hyun
    • Korean Journal of Environment and Ecology
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    • v.24 no.6
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    • pp.630-637
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    • 2010
  • This study was carried out to classify forest vegetation structure of Sobaeksan National Park from May to October in 2008 using the methodology of the ZM school's phytosociological analysis. The forest vegetation was classified into 1 community groups such as Quercus mongolica community group. Quercus mongolica community group was subdivided into 3 community such as Pinus densiflora community, Acer barbinerve community and Cornus controversa community. Pinus densiflora community was subdivided into Quercus variabilis group and Tilia amurensis group. Acer barbinerve community was also subdivided into Salix hallaisanensis group and Betula ermani group(subdivided into Taxus cuspidata subgroup and Betula ermani typical subgroup). Artificial forest type indicated 2 communities such as Larix leptolepis community and Pinus koraiensis community. Accordingly, the vegetation pattern of the surveyed areas were classified into 1 community groups, 5 communities, 4 groups, and 2 subgroups and the forest vegetation was classified into 8 units in total. The vegetation unit distributions was strongly correlated with sea level and topography in this research area.

The Characteristics of the Bird Communities by Land-use Types - The Case Study of Siheung City, Korea - (토지이용유형별 야생조류 군집구조 특성 분석 - 시흥시를 사례로 -)

  • Kim, Ji-Suk;Hong, Suk-Hwan;Oh, Choong-Hyeon
    • Korean Journal of Environment and Ecology
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    • v.26 no.3
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    • pp.313-321
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    • 2012
  • To analyze the bird communities by the land use type, we surveyed 43 plots in Siheung City, Korea from Mar. 2009 to Feb. 2010 and classified the community by TWINSPAN and DCA. Classification result by TWINSPAN was classified into 4 communities. In the first division, waterbirds, such as spot-billed duck(Anas poecilorhyncha) and great egret(Egretta alba) operated as the differential species. In the second and third division, little grebe(Tachybaptus ruficollis) and eurasian sparrow(Passer montanus) were operated as the differential species. The relationship between land use types and classified bird communities, all plots of community I were located in the forest. Community II plots were contained all urban and several semi-natural land use types. Community III contains stream and rice paddy. Plots in the reservoir were classified community IV. The stream and rice paddy were classified into different communities, which were colsely related with the size of wetland paddy. Community III had the highest species diversity index and community II had lowest. Community III also had the highest maximum species diversity index and evenness index. The result of this study, small stream and small rice paddy located within the city have insignificant characteristics as the habitat for birds. Management size of semi-natural land use for wildbird habitat in the urban area should be considered for showing their habitat characteristics. If the classification of biotope type based on the scale of rice paddy and urban park and the type of landuse type in the riverside then we should be consider the standard of minium area.

Vegetation Structure of the Bulguksa Buddhist Temple Forest in the Gyeongju National Park (경주국립공원 불국사 사찰림의 식생구조)

  • Kang, Hyun-Mi;Choi, Song-Hyun;Lee, Soo-Dong;Cho, Hyun-Seo;Kim, Ji-Suk
    • Korean Journal of Environment and Ecology
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    • v.26 no.5
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    • pp.787-800
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    • 2012
  • The purpose of this study was to investigate the vegetation structure of Bulguksa around Buddhist Temple Forest in the Gyeongju National Park. To do so, forty-two plots($100m^2$) were set up and surveyed. The surveyed plots were divided into four groups according to the analysis of classification by TWINSPAN; (I) Pinus densiflora-Pinus koraiensis community, (II) Pinus densiflora community, (III) Pinus densiflora-Acer palmatum community, (IV) Acer palmatum-Pinus densiflora community. The results of vegetation structure analysis were; Bulguksa around Buddhist Temple Forest in the Gyeongju National Park were dominated by Pinus densiflora. IV community, influx of Acer palmatum in Pinus densiflora community, Acer palmatum-Pinus densiflora community are believed to be a change to the community. But, recent spontaneously is growing Quercus variabilis, Quercus aliena, Quercus serrata, Quercus mongolica in understory and shrub layer. Later, it is expected that Pinus densiflora competition. The forest vegetation age of the study area is Pinus densiflora were dominant trees in forest was 30~100 years, old while that of Acer palmatum was 30~36 years old.