• Title/Summary/Keyword: evenness

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A Study on the Ichthyofauna of Tongbok Lake and its upper Streams from Autumn to Winter (동복호(同福湖)와 그 상류수계(上流水系)의 추(秋).동계(冬季) 어류상(魚類相)에 관한 연구(硏究))

  • Choi, Chung-Gil;Hwang, Yeong-Jin;Park, Jong-Cheon;Ra, Myeong-Suk;Lee, Jong-Bin
    • Korean Journal of Ichthyology
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    • v.6 no.1
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    • pp.28-38
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    • 1994
  • The ichthyofauna was investigated in Tongbok Lake and its tributaries from October, 1992 to January, 1993. Twenty-nine species representing 23 genera and 10 families were collected. Twenty-eight species in 22 genera and 9 families were from the stream area, while sixtween species in 14 genera and 7 families were from the lake area. Among these 14 species were classified as endemic species in Korea. Dominent species in the stream area were Zacco temmincki(28.04%) and Z. platypus (16.76%), whereas the lake area was overwhelmingly dominated by Hypomesus olidus(55.22%) and Z. platypus(44.31%). In the stream area. species diversity indices, evenness indices and dominant indices were 1.056, 0.730 and 0.270, respectively. In the area, the indices for species diversity, evenness and dominance were 0.314, 0.261 and 0.739, and those of body weights were 0.361, 0.300 and 0.700, respectively.

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The Community Structure and Dynamic of Parasitic Mites on House Rats (서울과 경기지역의 주가성 쥐에 기생하는 진드기군집의 구조와 동태에 관하여)

  • Kim Meung Hai;Hai Poong Lee
    • The Korean Journal of Ecology
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    • v.12 no.2
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    • pp.123-132
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    • 1989
  • The parasitic mites were collected from a total of 2,691 house rats in four areas of Seoul, Seongnam, Incheon and Yangsuri of Korea from January, 1983 to December, 1986, Infestation rates, the species composition of the mites. species diversity, evenness, dominance, similarity of the mites among the areas and monthly abundance were studied as follows: Among twenty-one species of mites identified from two species of house rats in the areas, 12 species belonged to Mesostigmata, 8 species to prostigmata and 1 species to Metastigmata. Out of twenty-one species, ten including Androlaelaps casalis were commonly found only on Rattus norvegicus, however, two including Haemogamsus serdjukovae only on Rattus rattus, and all the trombiculid mites were found in particular on R norvegicus. The highest infestation rates of the mites on the rats ranged from June to August in all the areas throughout the year. The species diversity of the mites was the highest (0.6280) in Yangsuri with the highest evenness value (0.5770) observed in Incheon. The seasonal species diversities in Seoul, Seongnam and Yangsuri were higher in April, October and March respectively than the other time of the year. The highest similarity value was calculated between Yangsuri and Seoul areas, compared with the lowest combination in Seoul and Seongnam areas. The seasonal indices of mites showed that the most abundant number of mites was observed in spring and summer in Seoul and Seongnam, in summer and autumn in Incheon and in the winter season in Yangsuri. The mesostigmatid and metastigmatid mites were collected abundantly in July and September from R. norvegicus and R rattus in Seoul with the highest number of the above mites found from R. norvegicus in June in Seongnam. Particularly in Yangsuri, a large number of the mites were collected all the year round.

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Vegetation Structure around Natural Trails in Mt. Jiri National Park (지리산국립공원 자연관찰로 주변의 식생구조)

  • Cho, Gyu-Nam;Kim, Deok-Sung;Cho, Min-Gee;Jung, Hye-Ran;Moon, Hyun-Shik
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.8 no.4
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    • pp.260-269
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    • 2006
  • This study was conducted to provide basic information for effective management strategies on nature trails in Mt. Jiri national park. Vegetation structure of nature trails in Yupyeong, Jungsanri, Hadong and Baekmudong districts was researched to accomplish the purpose of study. The tree and subtree layer consisted of 16 and 11 species for Yupyeong, 14 and 16 species for Jungsanri, 10 and 13 species for Hadong, and 19 and 10 species for Baekmudong district, respectively. The importance value of Quercu variabilis in the tree layer was highest for Yupyeong, Jungsanri and Baekmudong districts, and that of Pinus densiflora was highest for Hadong district. The herbaceous layer was composed of 70 species for Yupyeong, 53 species for Jungsanri, 65 species for Hadong, 57 species for Baekmudong districts, respectively. The value of species diversity ranged from 0.752 to 1.162, 0.957 to 1.085 and 1.283 to 1.506 at tree, subtree and shrub layer, respectively. Evenness ranged 0.752 to 0.983 at all layers for four nature trails in Mt. Jiri national park.

Seasonal Variation in Community Structure of Subtidal Seaweeds in Jeju Island, Korea (제주도 주변 해역 조하대 해조류 군집구조의 계절적 변동)

  • Kim, Bo Yeon;Ko, Jun-Cheol;Ko, Hyuck Joon;Park, Sung Eun;Cha, Hyung Kee;Choi, Han Gil
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.5
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    • pp.607-618
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    • 2013
  • Marine macroalgal community structures and characteristics of ocean environmental factors were examined seasonally at four sites in Jeju Island, Korea, from March to November 2012. A total of 71 macroalgal species were identified, including 9 green, 7 brown, and 55 red algae. Peyssonnelia capensis occurred at all study sites and in all seasons. The average annual biomass of seaweed was 991.84 g wet $wt/m^2$, with seasonal variations from 543.80 g in autumn to 1,284.17 $g/m^2$ in summer. A green alga, Codium coactum, was the dominant species, occupying 21.31% (211.39 $g/m^2$) of the total algal biomass in Jeju Island. Subdominant species were Ecklonia cava and Lithophyllum okamurae, comprising 20.85% (206.75 $g/m^2$) and 19.64% (194.75 $g/m^2$), respectively, of the total algal biomass in Jeju Island. The vertical distribution of subtidal seaweeds was represented by L. okamurae at 5 m depth, C. coactum at 10 m depth, E. cava at 5-10 m depth and P. capensis at the 20 m depth level. In the present study, crustose coralline algae, which predominated on barren ground, were subdominant species at all study sites. Community indices varied between 0.51-0.63 for dominance index (DI), 5.53-8.14 for richness index (R), 0.51-0.63 for evenness index (J'), and 2.04-2.32 for diversity index (H'). On the basis of seaweed biomass and community indices, Sinchang was the best preserved coastal area, showing maximal values in biomass, and evenness- and diversity-indices, and minimal value in the dominance index, representing stable environmental conditions. In contrast, the Onpyung and Topyeong sites, located near tourist venues such as Udo and Seogwipo were relatively poor habitats based on community indices and biomass. The present results could imply that climate changes alter seaweed community structure, and long-term monitoring of the study sites is required.

Structural Characteristics of Berchemia berchemiaefolia Stands at Mt. Gunja (군자산 자생 망개나무 임분의 구조적 특성)

  • Lee, Kyung-Su;Jung, Tae-Young;Park, Chull-Ha;Han, Ju-Hwan;Lee, Gui-Yong;Koo, Chang-Duck
    • Journal of Korean Society of Forest Science
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    • v.101 no.4
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    • pp.579-591
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    • 2012
  • Berchemia berchemiaefolia is a rare and endangered species and important as a honey resource. The purposes of this study were to investigate physical environmental factors and the population and community structure of Berchemia berchemiaefolia stands at Mt. Gunja in Sogrisan National Park in Chungcheongbuk-do. The B. berchemiaefolia stands belonged to deciduous forests in mid-temperate zone and were $5{\sim}25^{\circ}$ in slope, 30~90% in rock ratio, and 6.37 in soil pH. They had 656 trees within the area of 36 ha and their average density was 18.2 trees per ha. The trees within the stands were 11.8 m in tree height, 22.6 cm in DBH and 56 years old. The number of branched stems was the maximum 8 and 32.9% of the trees were branched. B. berchemiaefolia trees over 12 cm diameter occupied 89.9%, but young B. berchemiaefolia did only 11%. The structure of B. berchemiaefolia stands were classified into three groups as Acer pseudo-sieboldianum & A. mono community group, A. pseudo-sieboldianum & Quercus aliena community group, and B. berchemiaefolia & Quercus serata community group. The mean importance value of B. berchemiaefolia was 10.9%, while species diversity of the community ranged 0.77~1.31 and interspecific competition ranged 0.78~0.94. The dominance of the community ranged of 0.07~0.29 and the evenness ranged 0.71~0.93. Although B. berchemiaefolia was dominant in the habitat, but the species was already in natural successional stage to Cornus controversa or Ulmus davidiana var. japonica.

The Study of Forest Vegetation in Cryptomeria japonica D. Don Plantations (삼나무 인공조림(人工造林) 임분(林分)의 식생(植生)에 관한 연구(研究))

  • Lee, Jyung Seok
    • Journal of Korean Society of Forest Science
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    • v.69 no.1
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    • pp.42-50
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    • 1985
  • The vegetation of common Cryptomeria (Cryptomeria japonica D. Don) stands planted in Chonnam- province was investigated to obtain the fundamental informations for evaluation of suitable site and the improvement of managing method of the Cryptomeria stands in this region. The results investigated were summarized as follows; 1) The growth condition of common Cryptomeria planted 21-25-year-old stands was similar that of same species growing in Akidaken-district in Japan, while the growth condition of 51-58-year-old stands was not so good as that of Japanese. 2) Total number of plant species was 256. The number of floristic composition varied in the range of 42-99- species, which should be mere than those of Japanese. 3) The investigated sites were located in temperate southern part and in subtropic northern part of Korean peninsular. The types of understory vegetation were classified from I to IV class. 4) From the results of high max. possible diversity (H' max), and dominance (1-J') and from the low simple dominance (${\lambda}$) and evenness (J'), It could be concluded that vegetation was relatively in evenness. 5) From the low percent similarity, the specificity among the stands could be evaluated as considerable. 6) After the index of Morista, the 8th stand in Chang sung showed the generalized vegetation, while the 12th stand in Chang hung showed the specialized vegetation. 7) From the low values of Sneath-Sokal distance, the similarity among the stands investigated appeared very high.

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Weed Distribution and Its Plant Sociological Aspects on the Polder Land (간척지(于拓地)의 잡초발생(雜草發生) 및 분포의 식물사회학적(植物社會學的) 해석연구(解析硏究))

  • Lee, J.Y.;Guh, J.O.;Chang, H.S.;Bae, S.H.
    • Korean Journal of Weed Science
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    • v.4 no.2
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    • pp.135-142
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    • 1984
  • To obtain the basic information for weed management in polder land, a colligated assessment on weed distribution and it`s plant sociological indices on Gyewha polder land were arranged. At the situation of assessment, the Gyewha polder land was reclaimed with aim with paddy-rice production. As a result of reclamation, the salinity of most soil samples were below 0.3%, and acidity ranged from pH 5.5 to 6.5. Total weed species were counted as much as 17 species (3 gramineae, 7 cyperucese, and 8 broad-leaved species), and a most dominant species, Scirpus maritimus, were succeeded with Monochoria v., Eleocharis a., and Cyperus d., etc. by reclamation. Declining of soil salinity and soil pH, the number of weed species, individuals, biomass, species diversity, evenness, sociability index were increased, but the population particularity was weaken in tendencies. By developing of reclamation, the weed species which is summer annual broad leaf, wind and water disseminating, and tussock formed species are increased instead of salt-resistant, perennial cyperus, and rhizomatous extending species.

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Species Composition and Seasonal Variations of the Shrimp Beam Trawl Fisheries in the Adjacent Waters Geomundo, Korea (한국 거문도 주변 새우조망 어획된 새우류의 종조성과 계절변동)

  • 오택윤;김주일;고정락;차형기;이주희
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.39 no.1
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    • pp.63-76
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    • 2003
  • Species composition and seasonal variations of shrimp caught in the adjacent waters Geomundo, Korea were studied using the monthly catch of beam trawl fishery from November 1998 to October 1999. During in the study period, a total of 700,765 shrimps consisting 36 species, 27 genus and 11 families were collected. The community was dominated by Palaemon gravieri, Parapenaeopsis tenellus, Solenocela melantho and Plesionika izumiae. The peak abundance of shrimp occurred in summer, and low abundance in winter and spring. Major species occurred in area A, B and C was P. gravieri, and P. tenellus, and P. izumiae and S. melantho, respectively. The number of individual and abundance showed in July, and low in November. It was noted that values of species diversity, dominance and evenness indices were high in adjacent water Geomundo and lower in adjacent water Chodo and Chodo-Sonjukdo. Analysis of dendrogram of the clustering showed that there were two distinct groups; Geomundo group and Chodo-Sonjukdo group.

Community Analysis of Urban Forest around city of Seoul (서울시 근교에 위치한 도시숲 군집구조 분석)

  • Ro, Yu-Mi;Kang, Heejun;Lee, Sang-don
    • Korean Journal of Environment and Ecology
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    • v.29 no.4
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    • pp.599-604
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    • 2015
  • This study was conducted the vegetation clustering analysis for the 3 mountains of Mt. Bulam, Mt. Daemo, Mt. Bonghwa which were the urban forests of Seoul. Based on the results of the analysis related to the vegetation clustering, it was found that the clustering of Mt. Bulam consisted of pine trees(Pinus densiflora)-Mongolian oak(Quercus mongolica), Hornb eam(Carpinus laxiflora)-Pitch pine(P. rigida), oriental oak(Q. variabilis) - a wild pear tree(Sorbus alnifolia) while the clustering of Mt. Daemo consisted of Pitch pine-Japanese larch(Larix leptolepis), Poplar(Populus tomentig landulosa)- black birch(Betula davurica pall). Meanwhile, the clustering of Mt. Bonghwa consisted of pine trees-a wild pear tree Community and Sawtooth oak(Q. acutissima)-Cherry Blossoms(Prunus serrulata). In relation to the similarity index by region in Mt. Bulam, Mt. Daemo, and Mt. Bonghwa, the similarity index of Mt. Bulam and Mt. Daemo stood at as high as 0.634, suggesting the distribution of similar vegetation, and the dominance index of the Mt. Daemo region was found to be 0.166 which suggests the dominance of many species compared to other regions. In addition, the results of species diversity showed that Mt. Daemo had the highest stability, and the species diversity, maximum species diversity, evenness indices were highest in Mt. Bulam, followed by Mt. Bonghwa and Mt. Daemo. The dominance index was the lowest in Mt. Bulam, followed by Mt. Bonghwa and Mt. Daemo.

A Study on the Selection of Vegetation and Method for the Revegetation on the Highway Slope in Consideration of the Surrounding Environment (고속도로(高速道路) 비탈면(面)에서 주변환경(周邊環境)을 고려(考慮)한 녹화공법(綠花工法)과 식생선발(植生選拔)에 관(關)한 연구(硏究))

  • Woo, Bo-Myeong;Jeon, Gi-Seong;Kim, Kyung-Hoon;Choi, Hyung-Tae
    • Journal of Korean Society of Forest Science
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    • v.85 no.4
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    • pp.619-633
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    • 1996
  • This study was carried out from March 1995 to February 1996 to select suitable vegetation and measures for revegetation on the highway cut-slope in consideration of the surrounding environment in the middle region of Korea. The numbers of revegetation-measures type surveyed were eighteen measures as a whole in descending order of the Seed-spraying measures, Block-sod pitching measures, and Straw-mat mulching measures. The numbers of vegetation species by highway line were 243 in Chungbu, 223 in Jungang, 210 in Kyongbu 2, 199 in Kyongbu 1, 179 in Sohaean, 163 in Seoul circulation. 148 in Shingal-ansan, 141 in Second kyongin and 123 in Kyongin respectively. The highest index of species diversity(H') was in Kyongbu 1-line and the evenness(E') on upper site was greater than that of the lower site. The revegetation measures were selected in consideration of nature of soil, gradient, area and situation, and 83 species were selected as those for revegetation measures in highway cut-slope.

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