• Title/Summary/Keyword: richness indices

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Relationship between Physical Environmental Factors and Biological Indices of A Mountain Valley Stream (Mt. Cheoggye) (산간계류(청계산)의 물리적 환경요인과 생물지수의 관계)

  • Minjeong Yeo;Dongsoo Kong
    • Journal of Korean Society on Water Environment
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    • v.39 no.4
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    • pp.288-301
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    • 2023
  • This study aims to identify benthic macroinvertebrate fauna inhabiting at the mountain valley stream (Mt. Cheonggye) in Korea and the relationship between physical environmental factors and biological indices. Benthic macroinvertebrates were collected at five locations on August 24 and October 14, 2020, and were identified as 4 phyla, 7 classes, 16 orders, 42 families, and 72 species. Dominance ranged from 0.38 to 0.59, diversity 2.81 to 3.75, richness 3.25 to 4.63, evenness 0.65 to 0.84, and %EPT (Ephemeroptera-PlecopteraTrichoptera) richness value 42% to 73%, respectively. All sites were evaluated as a very good status by mostly biological indices based on tolerance of indicator organisms in Korea. As a result of principal component analysis, biological indices are classified into species-level indices and higher cartegory-level indices according to the taxonomic level of the indicator organism considered in each index. As a result of canonical correspondence analysis, it was confirmed that current velocity was a major factor that increased species richness and classified biological indices according to taxonomic category level. Water depth was a major factor related to the community indices, and the deeper the water depth, the lower the diversity and the evenness.

Species richness related to landscape characteristics of uninhabited islands in Korea

  • Rho, Paikho
    • Journal of Ecology and Environment
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    • v.33 no.2
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    • pp.105-114
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    • 2010
  • The principal objective of this study was to characterize the relationships between geographical conditions (e.g., island area, distance to mainland) and landscape structures of uninhabited islands, and to evaluate the effects of islands and their landscape structures on species richness. One hundred randomly selected islands and 5,000 m buffered areas derived from the boundaries of each island were used to summarize the number of observed bird species, and landscape pattern indices, particularly patch density, edge density, shape index, and mean nearest neighboring distance. Spatial arrangements of individual patch type at the class level, which are markedly affected by the distance from an island to the mainland, have a superior ability to explain the variances in species richness, as compared to the geographical conditions and landscape pattern indices at the landscape level. The results demonstrate that the patch type landscape structure is the primary factor affecting species richness, as well as the distance to the mainland. In particular, landscape pattern indices of cropland/pasture and woody cover are statistically significant in terms of explaining species richness, which suggests that food resources and appropriate conditions in landscape structures of habitat types are assumed as important elements in attracting bird species. This study also proposes the importance of evaluation on the landscape structure of each island, in order to designate protected areas and to establish a management plan for species conservation in uninhabited islands.

Soil Micro-arthropods Fauna in Plantations of the Korean White Pine (Pinus koraiensis). 4. Community Analysis of Oribatid mites (Cryptostigmata) (잣나무 조재지내 토양 미소 절지동물상에 관한 연구. 4. 날개 응애의 군집분석)

  • 권영립;윤경원
    • Korean journal of applied entomology
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    • v.34 no.2
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    • pp.120-126
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    • 1995
  • This study investigated the soil oribatid mite community at planatations of the Korean white pine, planted in different years. The soil samples $(10\times10\times5cm)$ were taken monthly from Jun 1988 to July 1989, and soil microarthropods in th sample were extracted using the Tullgren funnel for 72 hors. The diversity indices decreased at the older plantation sites with the maximum point in January and the minimum in September. The richness indices showed the maximum point in June and the minimum in may. The dominance indices increased at the older plantation and showed the maximum point in April, May, the minimum in January. The indices of aggregation of Oribatid mites species showed concentrated distribution in the average 1.9. The older plantation, the more indices increase. The seasonal variation of th indices tended to be greatest in April, August and at lowest in January. The richness indices was positively correlated with shannon-wiener, evenness indices. The dominance, aggregation indices was negatively correlated with shannon, evenness, richness indices.

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Plant community development in the first growing season of a created mitigation wetland bank as influenced by design elements

  • Ahn, Chang-Woo
    • Journal of Ecology and Environment
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    • v.33 no.4
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    • pp.363-376
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    • 2010
  • Vegetative communities of created wetlands often display lower species richness, less cover, higher occurrence of non-native or invasive species, and fewer obligate wetlands species than those in natural wetlands, thus failing to meet basic success criteria for wetland mitigation. This study examined the effects of two design elements, disking-induced microtopography and hydrologic regime, on the first year vegetation development pattern of a mitigation wetland newly created in the Virginia piedmont. Elevation and species cover were measured along replicate multiscale circular transects in two adjacent wetland sites that are different in their hydrologic regime. Two microtopographic indices, tortuosity (T) and limiting elevation difference (LD), were calculated from the elevation measurements. Both indices were higher in disked plots than non-disked plots, showing the effect of disking on microtopography. Out of forty-one vegetation taxa observed in the wetland, 29 taxa were naturally colonized and 12 taxa were seeded. All plots except one non-disked plot were dominated by wetland vegetation. Species richness and diversity were higher in disked than in non-disked plots. Vegetation community development seemed also influenced significantly by hydrologic regime of the site. The effect of microtopography on species richness and diversity was more pronounced in a relatively dry site compared to a wet site. In addition, percent cover, species richness and diversity of vegetation were positively correlated with microtopographic indices such as T and LD. Two design elements, microtopography and hydrologic regime, should be considered and incorporated in wetland creation to enhance plant community development.

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.

Fauna Diversity at the Deukjin River, Hapcheon-gun, Korea (합천군 덕진천의 동물상에 대한 다양성)

  • Huh, Man Kyu
    • Journal of Life Science
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    • v.28 no.1
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    • pp.105-109
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    • 2018
  • Biodiversity (or biological diversity) is defined as the variability of living organisms, the "diversity of life on Earth," and the complex relationships that make up ecosystems. This study aimed to investigate the spatial and temporal patterns in animal species composition and diversity at the Deukjin River, located in Hapcheon Province, Korea. The fauna community at the Deukjin River during 2016 season was identified with a total of 55 taxa, representing the following six classes: Mammalia (mammals), Actinopterygii (bony fish), Chondrichthyes (cartilaginous fish), Aves (birds), Amphibia (amphibians), Reptilia (reptiles), and invertebrates. The Berger - Parker index (BPI) for mammals varied from 0.233 (Station A) to 0.333 (Station D). The Shannon - Weaver index (H') and two diversity indexes (N1 and N2) for mammals and birds in the upper region were higher than those in the lower region. The values of ${\beta}$-diversity for animals varied from 0.229 for fish to 0.339 for invertebrates. The richness indices for animal taxa also varied among the stations and seasons. Station A showed considerably high richness in mammals, birds, and reptiles/amphibians. Although the richness indices (R1 and R2) for six animal kingdoms during the seasons were different from each other, the difference was not significant (p<0.05). The evenness indices for five animal kingdoms were different from each other, but again, the difference was not significant (p<0.05).

Diversity of Subcortical Arthropod Communities in Tropical and Temperate Forests

  • Choe, Jae-Chun
    • Animal cells and systems
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    • v.1 no.4
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    • pp.577-581
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    • 1997
  • Species diversity of subcortical arthropod communities were assessed in two tropical regions and two temperate regions. In the tropics, communities of subcortical arthropods were more diverse in La Selva, Costa Rica, than on Barro Colorado Island, Panama. Costa Rican communties yielses higher values of both Shannon and Simpson diversity indices than Panamanian communities. Compared to Panamanian communities, Costa Rican ones supported higher measures of both species richness and evenness. Between the two temperate regions, communities of subcortical arthropods in Korea scored consistently higher values of both Shannon and Simpson indices than the ones in eastern Massachusetts, U.S.A. When individual diversity components were compared, however, Korean communities yielded exceptionally high evenness measures but lower species richness than the communities in the U.S.A. Unusually high evenness values of Korean subcortical arthropods were due to extremely low population densities of all component species.

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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.

Seasonal variation of species composition by depths in deep sea ecosystem of the East Sea of Korea (동해 심해 생태계의 수심별 종조성 및 계절변동)

  • Sohn, Myoung-Ho;Lee, Hae-Won;Hong, Byung-Kyu;Chun, Yong-Yul
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.46 no.4
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    • pp.376-391
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    • 2010
  • To investigate seasonal variation and species composition by depth layers in the deep sea ecosystem of the East Sea of Korea, bottom trawl survey was conducted at 4 depth layers during spring and autumn from 2007 to 2009. A total of 47 species were collected and were composed of 23 fish species, 9 crustacea, 6 cephalopoda and 9 gastropoda. The main dominant species at each depth layers were Chionoecetes opilio in 300m, Berryteuthis magister in 500m, Chionoecetes japonicus in 700m and 900m. In spring, richness indices (R) showed low value of 2.01 in 500m depth, and high value of 2.16 in 300m depth. Diversity indices (H') showed low value of 1.53 in 300m depth, and high value of 2.09 in 700m depth. Dominance indices (D) showed low value of 0.15 in 700m depth, and high value of 0.31 in 300m depth. In Autumn, richness indices showed low value of 1.48 in 900m depth, and high value of 2.69 in 300m depth. Diversity' indices (H') showed low value of 1.13 in 300m depth, and high value of 2.23 in 700m depth. Dominance indices (D) showed low value of 0.14 in 700m depth, and high value of 0.54 in 300m depth. In spring, similarity analysis in each depth layers showed the difference between 900m and othe depth layer, on the contrary 500m and 700m showed the similarity. In autumn, similarity analyssis in each depth layers showed the difference between 700m and other depth layers, on the contrary 300m and 500m showed the similarity.

Effect of Using QuillBot on the Writing Quality of EFL College Students

  • Hye Kyung Kim
    • International Journal of Advanced Culture Technology
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    • v.11 no.4
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    • pp.42-47
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    • 2023
  • The majority of research on Automated Writing Evaluation (AWE) programs has focused primarily on Grammarly, whereas QuillBot and its use in English as a Foreign Language (EFL) classrooms remains limitedly explored. This study examined the effectiveness of using QuillBot on the writing quality of college students. A total of 26 participants took pre- and post-writing tests, and four analytical tools were applied to assess their writing quality in terms of syntactic complexity, lexical diversity, lexical richness, and readability. Results of the syntactic complexity analysis across the four indices demonstrates that the syntactic complexity of EFL writing increased significantly, and substantial differences were observed in lexical richness and readability. These results suggest that QuillBot can compensate for the drawbacks of Grammarly and assist EFL writers in improving their overall writing quality.