• Title/Summary/Keyword: Dominance Index

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Community Structure of Benthic Macroinvertebrates of Daecheon Stream in Busan City (부산 대천천의 저서성 대형무척추동물의 군집구조)

  • Son, Jung-Won;Hong, Jung-Hee
    • Journal of Environmental Science International
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    • v.19 no.2
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    • pp.185-196
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    • 2010
  • The distribution of benthic macroinvertebrates in Daecheon stream, an urban stream of Busan, was investigated to analyze the community structure of benthic macroinvertebrates. The collection was performed monthly at five(A~E) sites divided into three parts, upper, middle and lower, of stream from January to November, 2004. In physicochemical analysis of environmental factors, water quality parameters such as BOD, COD, conductivity and ABS were relatively increased in sites B and C. Whereas sites A, D and E showed little variations with good water quality parameters. However, water quality parameters in all surveyed sites showed gradual decrease with time toward improvement of water quality. A total of 8,226 individuals including 4 phyla, 6 classes, 9 orders, 302 families and 44 species were identified from five sites. The most dominant group was insect(class Insecta), and order Ephemeroptera and Diptera among insect was the largest member in species(30.6%) and individuals(75.0%) of benthic macroinvertebrates, respectively. The primary dominant species were Gammarus sp. and Ephemera strigata in site A, whereas Chironomus sp. and Brenchiura sowerbyi were dominated commonly in the other sites. In community analysis of benthic macroinvertebrates of Daecheon stream diversity index showed relatively low values, whereas dominance index was significantly high. Diversity index was the highest in site A, whereas the dominance index was the highest in site B. However, diversity index showed gradual increase with time showing adverse mode in dominance index. From these results, it can be suggested that long-term ecological monitoring of benthic macroinvertebrate fauna is needed for sustainable management of Daecheon stream.

Distribution of Ichthyoplankton in coastal waters of Nanji Island (당진 난지도 주변해역에서 분포하는 부유성 난 및 자치어의 종조성)

  • YOUN, Byeong-Il;HAN, Kyung-Ho;LEE, Sung-Hun
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.54 no.4
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    • pp.287-295
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    • 2018
  • The ichthyoplanktons were sampled to study distribution of the ichthyoplankton in coastal waters of Nanji-Island in August and November 2015 and January and May 2016. During the study, fish eggs of eight different species were collected. Engraulis japonicus was the most dominant species which accounted 44.80%. Sebastes schlegeli comprised 31.39% of the total larvae and juveniles. The diversity index of species per month of the collected juveniles at Nanji Island from 2015 to 2016 was 0.598-1.770 and the evenness index was 0.432-0.761. In case of dominance index was 0.619-0.897 against the evenness index. The analyzed species diversity index by the each station was 0.818-1.945 and the dominance index was 0.492-0.897 against the species diversity index. The months of August and May exhibited similar results. In addition, the community structure was very similar in state 2 and state 3.

Study of Dominance-Diversity on Quercus mongolica Forests in Kangwon-do (강원도 신갈나무 군락의 우점도 다양성에 관한 연구)

  • 장규관;송호경
    • Korean Journal of Environment and Ecology
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    • v.11 no.2
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    • pp.160-165
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    • 1997
  • The objective of this study was to analyze dominance-diversity of Quercus mongolica community which characterize the boreal-temperate deciduous forest in Korea. Employing the releve method of Muller-Domboes and Ellenberg, 100 quadrats were sampled in the natural forest of Mt. Odae, Mt. Chumbong and Mt. Jungwang in Kangwon-do, where Quercus mongolica community is in the situation of climax or subclimax. On the basis of Braun-Blanquet method, field survey, which accounts ffor the characters of the species structure of Quercus mongolica community, was carried out between 1991 and 1994. Quercus mongolica community was relatively in a stable condition because of the even distribution of its various indices: the species diversity index was 0.4~1.2; the species richness index was 2~11; the evenness index was 0.6~0.9. The dominance-diversity curve were comparatively of lognormal distrivution with a gentle slope in all communities. The species sewuence curve for Quercus mongolica - Lindera obtusiloba community had relatively a steep slope, which meant that the evenness of the community would be low. The species sequence curve for Quercus mongolica - Carpinus cordata community had a slow slope, which meant that the evenness and the stability of the community would be high.

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Effects of dominance frequency of plant species to increase productivity of cattle feed in Japan

  • Yulianto, Roni;Xuan, Tran Dang
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.48-48
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    • 2017
  • The objectives of this study were to determine the dominance frequency of plant species between spring and summer, to provide useful information toward the conservation to increasing production cattle feed in grazing area in Hiroshima, Japan. The frequency of dominant plant species can adapt in the spring and summer, that consist of Paspalum dilatatum (spring 69.32% and summer 78.98%), Paspalum notatum (spring 47.73% and summer 98.30%), Trifolium repens (spring 73.86% and summer 81.25%). The observed plant species also influenced some productivity, which consists of plant height (spring 16.64 cm and summer 21.55 cm), vegetation cover rates (spring 77.18% and summer 81.36%, chlorophyll content (spring 41.72 mg/g Fw and summer 36.28 mg/g Fw), diversity index (spring 0.94 and summer 0.80), evenness index (spring 0.93 and summer 0.67), and species numbers (spring 32.0 and summer 21.0). It is proposed that Paspalum dilatatum, Paspalum notatum, and Trifolium repens, can be used to increase productivity of plant species as cattle feeds.

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A Comparative Study on the Structural Characteristics of the Forest Vegetation at the Southern and Northern Slopes of the Eastern Ridge in Mt. Cheonma, Central Korea (천마산 동부릉선 남북사면의 삼림식생의 구조적 특성에 관한 비교 연구)

  • Lee, Nam-Ju;Yang-Jai Yim
    • The Korean Journal of Ecology
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    • v.11 no.4
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    • pp.213-225
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    • 1988
  • The plant communities of the eastern ridge in Mt. Cheonma, Central Korea, Quercus mongolica, Q mongolica-Acer pseudo-sieboldianum, and Q. mongolica-Rhododendron schlippenbachii communities in the northern slope and Q. variabilis and Q. cutissima communities in the southern slope were detected by Zurich-Montpellier method. The undergrowth of Q mongolica community in the northern slope was dominated by Ainsliaea acerifolia, Carex siderosticta, Astilbe chinensis var. davidii, Heloniopsis orientalis, Pseudostellaria palibiniana, ranging 3.3 to 2.2 in dominance-sociability, while the those of Q variabilis and Q acutissima in the southern slope were dominated by Spodiopogon cotulifer, Artemisia keiskeana, Carex humilis, Atractylodes japonica, Lysimachia clethroides and Disporum smilacinum with similar degree in dominance-sociability to that of Q mongolica community. The two communities were considered as regenerating forest after severe disturbance judging by their age structure. The relationship between Shannon's diversity index (H') and Simpson's dominance index (i) was in reciprocal proportion in both two communities. The Q. mongolica and Q. variabilis communities were showed 13 and 12 m respectively. Seasonal changes of undergrowth coverage in the two communities were seemed to be affected especially with soil moisture among environmental factors such as temperature, light intensity, relative humidity and organic matter.

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An Analysis on Possibility and Effect of Market Power under the 3rd Long Term Power Plan (제3차 전력수급기본계획에 따른 시장지배력 행사가능성 및 영향분석)

  • Lee, Jae-Gul;Park, Min-Hyuk;Ahn, Nam-Sung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.6
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    • pp.1017-1022
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    • 2007
  • In this paper, we try to analyze the likelihood of exercising the power of market dominance by certain generators in future power industry of Korea. Firstly, we estimated installed generation capacity and sales volume of electricity in Korea, based on 'The 3rd Long Term Power Plan' which was announced in December 2006. Secondly, we calculated HHI, an index showing the degree of concentration of an industry, and RSI, an index showing how adequate the supply of goods or services of an industry is, using Fast-Forward. Thirdly, assuming a major generator employs the strategy of withholding a part of its available capacity at a peak time, we simulated hypothetical movement of SMP over a certain period of time, which is compared with that obtained without assuming such strategy to generate Lerner Index. an index showing the degree of market power of a monopoly. Regulators, home and abroad, have not given much interest in analyzing the effect of market dominance that is likely to be exercised by certain players in the future. That said, this paper provides insight into developing methodologies of analyzing and mitigating such effect by proposing the above indices to gauge it. In addition, this paper also shows the potential impact of employing capacity withholding strategy on the financial account of a dominant generator.

Insect Diversity in Non-organic and Organic Chinese Cabbage and Pepper Farms (유기 재배 및 관행 재배 배추와 고추밭의 곤충상 조사)

  • Jin, Joon-Ho;Cho, Sae-Youll
    • The Korean Journal of Pesticide Science
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    • v.14 no.3
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    • pp.255-260
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    • 2010
  • Insect diversities in non-organic and organic Chinese cabbage and pepper fields were studied in 2009. Sixty-two species in 9 orders and 24 species in 6 orders were collected in organic and non-organic Chinese cabbage fields, respectively. In pepper fields, insect diversity was also higher in organic fields than in non-organic ones. Dominance index, diversity index, richness index, and evenness index in organic fields were higher than those in non-organic fields.

Species composition and seasonal variations of fish in Eelgrass(Zostrera marina) Bed in coastal waters off Jedo, Yeosu (여수 제도 연안에서 잘피밭에 서식하는 어류의 종조성 및 계절변동)

  • Yu, TaeSik;Im, InHyeon;Lee, SeongHoon;Han, SeungJo;Han, KeongHo
    • Journal of Marine Bioscience and Biotechnology
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    • v.13 no.1
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    • pp.58-65
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    • 2021
  • In 2012, fishes caught by three-side fyke net in the coastal waters of Jedo were assessed for species composition and seasonal fluctuation in their abundance. The fish were caught at two research stations (St.) and were found to comprise 53 species, 39 families, and 9 orders. The dominant species were Takifugu niphobles, Lateolabrax maculatus, and Acanthopagrus schlegelii. To gain a measure of their biodiversity, all the species were assessed for their number, richness, diversity, evenness, and dominance. The highest and lowest number of total caught fish individuals was recorded in summer and winter, respectively. The diversity index was the highest in summer and lowest in winter. The evenness index was the highest in summer and lowest in spring. The richness index was highest in summer and lowest in winter. Furthermore, the dominance index was highest in spring and lowest in autumn.

Community Characteristics of Benthic Macroinvertebrates according to Growth Environment at Rural Palustrine Wetland (농촌지역 소택형습지의 생육환경에 따른 저서성대형무척추동물 군집 특성)

  • Son, Jin-Kwan;Kim, Nam-Choon;Kim, Mi-Heui;Kang, Banghun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.5
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    • pp.129-144
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    • 2012
  • This study was conducted to understand the community characteristics of benthic macroinvertebrates according to Growth Environment at 6 Palustrine Wetlands in a rural area. As growth environment factors, size, water depth, water inlet and water outlet, land-use and water environment was analyzed. Two years' quantitative collection of benthic macroinvertebrate was carried out, and it executed community analysis and ESB index calculation and also carried out twinspan, MDS and correlation analysis. As a result, the collected benthic macroinvertebrate was 1254 individuals with 3 Phylums, 6 Classes, 14 Orders, 35 Families, 52 Genera and 61 Species. Odonata and Coenagreionidae had the highest species and individuals. Dominance Index was 0.252~0.698, Diversity Index was 1.661~2.902, Evenness Index was 0.414~0.724, and Species Richness Index was 1.990~6.224. As a result of community analysis, when correlation analysis was executed, Dominance Index had the opposite tendency with Diversity Index and Evenness Index, which had the same tendency with the previous studies. When ESB Index was calculated, Grade 2 (polluted) had the highest species with 48 species (78.7%). It is determined from the Environmental quality evaluation and saprobity evaluation result according to ESB index that there is a need to revise environmental evaluation system more specifically. As a result of MDS analysis, the subject spots A and D had the highest similarity, and the subject spot E and D had a relatively high similarity. The life environment that is the closest related with species diversity is estimated by the land-use. As for number of Individual, it seems to have the closest relation with inlet, which is to be determined as a characteristics of Palustrine Wetland. Through such investigation, this study is expected to be utilized for various types of habitats including ecological pond and to be utilized for the increase of species diversity in rural areas.

VBioindex: A Visual Tool to Estimate Biodiversity

  • Yu, Dong Su;Yoo, Seung Hwa
    • Genomics & Informatics
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    • v.13 no.3
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    • pp.90-92
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    • 2015
  • Biological diversity, also known as biodiversity, is an important criterion for measuring the value of an ecosystem. As biodiversity is closely related to human welfare and quality of life, many efforts to restore and maintain the biodiversity of species have been made by government agencies and non-governmental organizations, thereby drawing a substantial amount of international attention. In the fields of biological research, biodiversity is widely measured using traditional statistical indices such as the Shannon-Wiener index, species richness, evenness, and relative dominance of species. However, some biologists and ecologists have difficulty using these indices because they require advanced mathematical knowledge and computational techniques. Therefore, we developed VBioindex, a user-friendly program that is capable of measuring the Shannon-Wiener index, species richness, evenness, and relative dominance. VBioindex serves as an easy to use interface and visually represents the results in the form of a simple chart and in addition, VBioindex offers functions for long-term investigations of datasets using time-series analyses.