• Title/Summary/Keyword: Shannon diversity index

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The Estimation of Succession Index by Community Types in the Natural Deciduous Forest of Mt. Jumbong (점봉산 일대 천연활엽수림의 군집 유형별 천이지수 추정)

  • Jin, Guang Ze;Kim, Ji Hong
    • Journal of Korean Society of Forest Science
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    • v.95 no.6
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    • pp.723-728
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    • 2006
  • Since the forest succession is changing process in the structure and function of a forest for the long period of time, the objectivity of the process could be improved through the development of model or statistical methodology. This study was carried out to estimate succession index based on climax index and species composition parameters, thereupon to compare the succession index with life form and species diversity so as to grasp the information of quantitative successional process for the six community types in the natural deciduous forest of Mt. Jumbong area. The results indicated that Quercus mongolica-Tilia amurensis community had the greatest succession index of 67.5, followed by Abies holophylla-Fraxinus mandshurica community with 67.4. Juglans mandshurica-Cornus controversa community was recorded the smallest value of 60.5. The succession index of overstory tended to increase considerably at the stage of steady state for all community types except Quercus mongolica-Tilia amurensis community. However, The index of midstory hardly varied as the forest succession would progress for all community types. The succession index was negatively correlated to wind-water dispersion type of life form and positively to animal dispersion type at the 5% probability level. On the other hand, the index was not significantly correlated to the species richness and Shannon's species diversity index.

Effects of reforestation approaches, agroforestry and woodlot, on plant community composition, diversity and soil properties in Madhupur Sal forest, Bangladesh

  • Hasan, Mohammad Kamrul;Islam, Md. Tariqul;Akter, Rojina;Roshni, Nasima Akther
    • Journal of Ecology and Environment
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    • v.46 no.3
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    • pp.204-217
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    • 2022
  • Background: Increasing land demands for food production have led to biodiversity loss and land degradation in the Madhupur Sal forest. Reforestation activities such as agroforestry and woodlot plantation support the conservation of diversity, restoration of forest and prevention of soil erosion in degraded natural Sal forest. Knowing about these reforestation activities, this study is needed to compare the species composition, richness, and soil nutrients of these two plantation activities to the natural Sal forest in the degraded Madhupur Sal forest in Bangladesh. Results: The analysis showed that in between the reforestation activities, the highest Shannon-Wiener index (1.79), evenness (0.60) and Simpson's index (0.79) were found in the agroforestry site compared to the woodlot plantation site. On the contrary, the highest species richness (n = 14), tree basal area (19.56 m2 ha-1), Margalef's index (1.96) were recorded in woodlot plantation than in the agroforestry site. We observed that at 0-15 cm depth, soil organic matter (2.39%), total nitrogen (0.14%), available phosphorous (62.67 ㎍ g-1) and exchangeable potassium (0.36 meq/100 g) in agroforestry plots were significantly higher compared to other forest sites. At topsoil (15-30 cm depth), soil organic matter (1.67%) and available phosphorous (21.09 ㎍ g-1) were found to be higher in agroforestry site. Conclusions: Both reforestation approaches improved soil function, although woodlot plantation had the higher species richness. Therefore, plantation activities by the sustainable implementation of these two practices are the best alternative to restore the biodiversity, richness and conserve soil fertility in the Madhupur Sal forest of Bangladesh.

MEASURE OF DEPARTURE FROM QUASI-SYMMETRY AND BRADLEY-TERRY MODELS FOR SQUARE CONTINGENCY TABLES WITH NOMINAL CATEGORIES

  • Kouji Tahata;Nobuko Miyamoto;Sadao Tomizawa
    • Journal of the Korean Statistical Society
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    • v.33 no.1
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    • pp.129-147
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    • 2004
  • For square contingency tables with nominal categories, this paper proposes a measure to represent the degree of departure from the quasi-symmetry (QS) model and the Bradley-Terry (BT) model. The measure proposed is expressed by using the Cressie and Read (1984)'s power-divergence or Patil and Taillie (1982)'s diversity index. The measure lies between 0 and 1, and it is useful for comparing the degree of departure from QS or BT in several tables.

Generalized Measure of Departure From Global Symmetry for Square Contingency Tables with Ordered Categories

  • Tomizawa, Sadao;Saitoh, Kayo
    • Journal of the Korean Statistical Society
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    • v.27 no.3
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    • pp.289-303
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    • 1998
  • For square contingency tables with ordered categories, Tomizawa (1995) considered two kinds of measures to represent the degree of departure from global symmetry, which means that the probability that an observation will fall in one of cells in the upper-right triangle of square table is equal to the probability that the observation falls in one of cells in the lower-left triangle of it. This paper proposes a generalization of those measures. The proposed measure is expressed by using Cressie and Read's (1984) power divergence or Patil and Taillie's (1982) diversity index. Special cases of the proposed measure include TomiBawa's measures. The proposed measure would be useful for comparing the degree of departure from global symmetry in several tables.

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The Classification of Forest Communities by Cluster Analysis in Mt. Seokbyung Experimental Forest of Gangwon-Do

  • Chung, Sang-Hoon;Kim, Ji-Hong
    • Journal of Korean Society of Forest Science
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    • v.99 no.5
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    • pp.736-743
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    • 2010
  • This study examined the ecological attributes of classified forest community by cluster analysis in the mixed forest of Mt. Seokbyung Experimental Forest of Gangwon-Do. The vegetation data were collected in randomly established 51 sample plots (2.04 ha) and analysis adopted the cluster analysis, importance value index, and Shannon's diversity index. Main results were as follows; 1) the study area was classified into 4 clusters (A, B, C and D). 2) The cluster A was dominated by Pinus densiflora with an importance value of 71.6%. The most dominant species in the cluster B and cluster C were Larix leptolepis (57.1%) and Quercus mongolica (40.2%), respectively. Finally, The cluster D was dominated by P. densiflora (30.6%) and Q. mongolica (31.0%) with the mixed forest. 3) In the P. densiflora community (cluster A), distribution of DBH class showed a reverse J-shaped curve. In the L. leptolepis community (cluster B), individuals of dominant species had the bell-shaped distribution. Oak species indicated uniform distribution of DBH class (under 25 cm) in the mixed P. densiflora - Q. mongolica community (cluster D). 4) The species diversity index of the communities in descending order were: Pinus densiflora - Q. mongolica community > Larix leptolepis community > Pinus densiflora community > Quercus mongolica community.

Analysis on the Relationship between Biological Indices and Survey Area of Benthic Macroinvertebrates Using Mathematical Model (수학적 모형을 이용한 저서성 대형무척추동물 군집지수-조사면적 관계 해석)

  • Kong, Dongsoo;Kim, Ah Reum
    • Journal of Korean Society on Water Environment
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    • v.31 no.6
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    • pp.610-618
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    • 2015
  • This study was conducted to find out the influence of sample size (accumulated survey areas) on the seven biological indices of benthic macroinvertebrates. BMI, the index similar to Zeilika-Marvan’s saprobic index, tended to be independent on the variations of sample size. The other indices (Shannon-Weaver’s diversity, Margalef’s richness, Menhinick’s richness, Pielou’s evenness, and Lenat’s EPT index) showed the considerable variations along with the increase of sample size and environmental conditions. To get the appropriate index values, it should be sampled at least 6 replicates more based on 30×30cm Surber sampler. In addition, the habitat heterogeneity index of benthic macroinvertebrates suggested in this study, it will be able to be used for evaluating the heterogeneity of habitats.

Plant Community Structure of Paekdam-Valley in Soraksan National Park (설악산국립공원 백담계곡 식물군집구조)

  • 이경재;김종엽;김동완
    • Korean Journal of Environment and Ecology
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    • v.11 no.4
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    • pp.450-461
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    • 1998
  • To investigate the plant community structure of Paekdam-Valley in Soraksan National Park, fifty-two plots have been set up and surveyed. By DCA ordination technique, the plant communities were classified into fkve community types, which were Pinus densiflora community and Q. mongolica community. It was supposed that Q. serrata community change to C. laxiflora community. It seemed that P. densiflora community, deciduous broad-leaved mixed forest and Q. serrata community would not be replace by another woody species. And it seemed that C. laxiflora community succeeded to Q. serrata community, so it was similar to the typical ecological succession of natural forest in the middle temperate regions. The range of Shannon's diversity index was 0.9827~1.2946(Unit area : 400m$^2$) and that was over another Korean National Parks area relatively.

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Relationship between Diversity and Productivity at Ratargul Fresh Water Swamp Forest in Bangladesh

  • Sharmin, Mahmuda;Dey, Sunanda;Chowdhury, Sangita
    • Journal of Forest and Environmental Science
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    • v.32 no.3
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    • pp.291-301
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    • 2016
  • One of the most concerned topics in ecology is the relationship between biodiversity and ecosystem functioning. However, there are few field studies, carried out in forests, although many studies have been done in controlled experiments in grasslands. In this paper, we describe the relationship pattern between three facets of diversity and productivity at Ratargul Fresh Water Swamp Forest (RFWSF) in Bangladesh, which is the only remaining fresh water swamp forest of the country. Sixty sample plots were selected from RFWSF and included six functional traits including leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), tree height, bark thickness and wood density. In analyzing TD, we used Shannon diversity and richness indices, functional diversity was measured by Rao's quadratic entropy (Rao 1982) and Faith's (1992) index was used for phylogenetic diversity (PD). It was found that, TD, FD and PD were positively related with productivity (basal area) due to resource use complementarity but surprisingly the best predictor of tree productivity was FD. The results contribute to the understanding the effects of biodiversity loss and it is essential for conservation decision-making and policy-making of Ratargul Fresh Water Swamp Forest.

Genetic Diversity and Structure of the Korean Rare and Endemic Species, Deutzia pdaniculata Nakai, as Revealed by ISSR Markers (한국 희귀 특산식물 꼬리말발도리 집단의 유전적 다양성 및 구조)

  • Son, Sung-Won;Choi, Kyoung Su;Park, Kyu Tae;Kim, Eun-Hye;Park, Seon Joo
    • Korean Journal of Plant Resources
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    • v.26 no.5
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    • pp.619-627
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    • 2013
  • Deutzia paniculata Nakai is a Korean endemic species that has a very restricted distribution in Gyeongsang-do, South Korea. The genetic diversity and structure of five populations of D. paniculata were investigated using 31 ISSR loci from six primers. The Shannon's index (0.429) and genetic diversity (0.271) were relatively higher than those of other rare plant species in Korea. The Miryang (MY) and Yangsan (YS) populations, which have higher flowering rates than the other populations, showed greater genetic diversity than the other populations. An analysis of the molecular variance (AMOVA) showed that 16% of the total variation could be attributed to differences among the populations, and 84% to the differences within populations, indicating moderate gene flow among adjacent populations. The high genetic diversity and low genetic differentiation in the Deutzia paniculata populations, which have a restricted distribution, is considered to be affected by outcrossing of the mating system and abundant individuals in the populations. These results suggest that ex situ conservation strategies are needed to sustain the current genetic diversity of D. paniculata.

Diversity and Genotypic Structure of ECOR Collection Determined by Repetitive Extragenic Palindromic PCR Genome Fingerprinting

  • HWANG KEUM-OK;JANG HYO-MI;CHO JAE-CHANG
    • Journal of Microbiology and Biotechnology
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    • v.15 no.3
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    • pp.672-677
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    • 2005
  • The standard reference collection of strains for E. coli, the ECOR collection, was analyzed by a genome-based typing method. Seventy-one ECOR strains were subjected to repetitive extragenic palindromic PCR genome fingerprinting with BOX primers (BOX-PCR). Using a similarity value of 0.8 or more after cluster analysis of BOX-PCR fingerprinting patterns to define the same genotypes, we identified 28 genotypes in the ECOR collection. Shannon's entropy-based diversity index was 3.07, and the incident-based coverage estimator indicated potentially 420 genotypes among E. coli populations. Chi-square test of goodness-of-fit showed statistically significant association between the genotypes defined by BOX-PCR fingerprinting and the groups previously defined by multi-locus enzyme electrophoresis. This study suggests that the diversification of E. coli strains in natural populations is actively ongoing, and rep-PCR fingerprinting is a convenient and reliable method to type E. coli strains for the purposes ranging from ecology to quarantine.ine.