• Title/Summary/Keyword: Research Diversity

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Comparative Analysis of Diversity Characteristics (γ-, α-, and β-diversity) of Biological Communities in the Korean Peninsula Estuaries (하구 순환 유지 여부에 따른 하구 주요 생물 군집별 다양성 특성 연구: 열린하구와 닫힌하구에서의 γ-, α- 및 β-다양성 비교)

  • Oh, Hye-Ji;Jang, Min-Ho;Kim, Jeong-Hui;Kim, Yong-Jae;Lim, Sung-Ho;Won, Doo-Hee;Moon, Jeong-Suk;Kwon, Soonhyun;Chang, Kwang-Hyeon
    • Korean Journal of Ecology and Environment
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    • v.55 no.1
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    • pp.84-98
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    • 2022
  • Estuary is important in terms of biodiversity because it has the characteristics of transition waters, created by the mixing of fresh- and seawater. The estuarine water circulation provides a variety of habitats with different environments by inducing gradients in the chemical and physical environment, such as water quality and river bed structure, which are ultimately the main factors influencing biological community composition. If the water circulation is interrupted, the loss of brackish areas and the interception of migration of biological communities will lead to changes in the spatial distribution of biodiversity. In this study, among the sites covered by the Estuary Aquatic Ecosystem Health Assessment, we selected study sites where changes in biodiversity can be assessed by spatial gradient from the upper reaches of the river to the lower estuarine area. The α-, γ- and β-diversity of diatom, benthic macroinvertebrates, and fish communities were calculated, and they were divided into open and closed estuary data and compared to determine the trends in biodiversity variation due to estuarine circulation. As results, all communities showed higher γ-diversity at open estuary sites. The benthic macroinvertebrate community showed a clear difference between open and closed estuaries in β-diversity, consequently the estuarine transects were considered as a factor that decreases spatial heterogeneity of their diversity among sites. The biodiversity trends analyzed in this study will be used to identify estuaries with low γ- and β-diversity by community, providing a useful resource for further mornitoring and management to maintain estuarine health.

Genetic Diversity and Population Genetic Structure of Black-spotted Pond Frog (Pelophylax nigromaculatus) Distributed in South Korean River Basins

  • Park, Jun-Kyu;Yoo, Nakyung;Do, Yuno
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.2 no.2
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    • pp.120-128
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    • 2021
  • The objective of this study was to analyze the genotype of black-spotted pond frog (Pelophylax nigromaculatus) using seven microsatellite loci to quantify its genetic diversity and population structure throughout the spatial scale of basins of Han, Geum, Yeongsan, and Nakdong Rivers in South Korea. Genetic diversities in these four areas were compared using diversity index and inbreeding coefficient obtained from the number and frequency of alleles as well as heterozygosity. Additionally, the population structure was confirmed with population differentiation, Nei's genetic distance, multivariate analysis, and Bayesian clustering analysis. Interestingly, a negative genetic diversity pattern was observed in the Han River basin, indicating possible recent habitat disturbances or population declines. In contrast, a positive genetic diversity pattern was found for the population in the Nakdong River basin that had remained the most stable. Results of population structure suggested that populations of black-spotted pond frogs distributed in these four river basins were genetically independent. In particular, the population of the Nakdong River basin had the greatest genetic distance, indicating that it might have originated from an independent population. These results support the use of genetics in addition to designations strictly based on geographic stream areas to define the spatial scale of populations for management and conservation practices.

México: Ambiente, cultura y sociedad. Un análisis desde la perspectiva del modelo RECREA

  • Perez, Jose Isabel Juan;Michel, Gerardo Gomez
    • Iberoamérica
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    • v.22 no.2
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    • pp.153-179
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    • 2020
  • In the Mexican territory the cultural diversity is associated with the environmental diversity, this is demonstrated by the presence of native groups that inhabit the regions of the country, which are characterized by the management of various natural resources that they obtain from the terrestrial and aquatic environments of each of the regions. Through the RECREA Model: complex thinking, information and communication technologies and research-action, complemented with fundamentals of geography, environmental geography, cultural ecology, field work and cartographic information, we explained and analyzed the association between environmental diversity and cultural diversity to demonstrate that in Mexico there are still links between the environment, society and culture, a situation that determines the existence of human groups that subsist in the context of a global capitalist system that extracts in an unsustainable way natural resources. Based on these results, an instructional model is made to put it to practice with international students, in this case from Japan and South Korea, to allow the observation of its functionality in transmitting the aforementioned results on environmental and cultural diversity in Mexico during the teaching-learning process.

The Effects of Diversity Management on Perceived Performance and Organizational Commitment : Focusing on National Research Institutes (다양성 관리가 인식된 성과와 조직몰입에 미치는 영향 : 국책연구기관을 중심으로)

  • Park, Jeong-Min;Choi, Do-Lim;Lee, Sun-Ho
    • The Journal of the Korea Contents Association
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    • v.20 no.2
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    • pp.626-635
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    • 2020
  • Recently, there have been active discussions of inclusiveness orientation. Thus, this study aimed to verify the influences of diversity management on the perceived performance and organizational commitment after paying attention to the diversity of human resources. For this, this study conducted a direct survey targeting the members of a research institution funded by the government. From May 2nd 2018 to July 2nd 2018, total 200 questionnaires were distributed through direct visit or department heads/team leaders, and then total 191 questionnaires were used for the final analysis. The questionnaires were sent to 200 members of the national research institutions funded by the government from May 2nd to July 2nd, and then 191 were collected and used for the analysis in this study. As the results of this study verified the positive influences of diversity management on organization, it would be necessary to verify the managerial effectiveness of diversity management by considering the concrete indexes of diversity management and verifying the influences of other performance variables. Due to the necessity to cope with the diversified characteristics of human resources, it would be needed to establish the alternative in the level of public organization or proper management.

Bacterial Diversity of Culturable Isolates from Seawater and a Marine Coral, Plexauridae sp., near Mun-Sum, Cheju-Island

  • Lee, Jung-Hyun;Shin, Hyun-Hee;Lee, Deuk-Soo;Kwon, Kae-Kyung;Kim, Sang-Jin;Lee, Hong-Kum
    • Journal of Microbiology
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    • v.37 no.4
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    • pp.193-199
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    • 1999
  • Fifty-eight strains showing different colony morphological characteristics on various media were isolated from marine coral (Plexauridae sp.) and ambient seawater near Mun-Sum, Cheju-Island in 1998. Bacterial diversity was studies by phylogenetic analysis of the partial 16S rRNA gene sequences. All isolates representing the bacterial domain included affiliates of the high G+C (59%) and los G+C (3%) subdivision of Gram positive bacteria, and the alpha (33%) and gamma (5%) subdivision of the Proteobacteria. The 16S rDNA sequence similarity of the isolates was in the 88.3 to 100% range (average, 95.6%) to reported sequence data. In the comparison of the isolates from marine coarl and ambient seawater, more diverse groups belonging to ${\alpha}$-Proteobacteria were preferentially obtained from seawater.

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Bacterial Diversity in Soil Surround Subterranean Termites-Damaged Wooden Buildings in Seonamsa Temple and Effect of the Termites on Bacterial Diversity in Humus Soil

  • Kim, Young Hee;Lim, Boa;Lee, Jeung Min;Hong, Jin Young;Kim, Soo Ji;Park, Ji Hee
    • Journal of Conservation Science
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    • v.37 no.4
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    • pp.357-361
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    • 2021
  • In order to determine the changes in microbial community due to termites, soil microorganisms surrounding the termites were investigated. First, bacterial communities from soil with termites collected at Seonamsa temple, Suncheon city, Korea were compared by next-generation sequencing (NGS, Illumina Miseq). The bacterial composition of soil from Daeungjeon without termites and the soil from Josadang, Palsangjeon, and Samjeon with termites were compared. Next, the bacterial composition of these soils was also compared with that of humus soil cultured with termites. A total high-quality sequences of 71,942 and 72,429 reads were identified in Seonamsa temple's soil and humus soil, respectively. The dominant phyla in the collected Seonamsa temple's soil were Proteobacteria (27%), Firmicutes (24%) and Actinobacteria (21%), whereas those in the humus soil were Bacteriodetes (56%) and Proteobacteria (37%). Using a two-dimensional plot to explain the principal coordinate analysis of operational taxonomic unit compositions of the soil samples, it was confirmed that the samples were divided into soil with and without termites, and it was especially confirmed that the Proteobacteria phylum was increased in humus soil with termites than in humus soil without termites.

Development and Characterization, and Application of Ten Polymorphic Microsatellite Markers in the Crested Ibis Nipponia nippon from South Korea

  • Choi, Eun Hwa;Kim, Gyeongmin;Baek, Su Youn;Kim, Sung Jin;Hwang, Jihye;Jun, Jumin;Jang, Kuem Hee;Ryu, Shi Hyun;Hwang, Ui Wook
    • Animal Systematics, Evolution and Diversity
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    • v.36 no.2
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    • pp.154-158
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    • 2020
  • The Asian crested ibis Nipponia nippon is one of the world's most endangered species. Except for the Sanxii population from China, it is known that all of the crested ibis populations from East Asia have been extinguished. In these days, most of them are being inbred as captive populations in China, South Korea, and Japan, which caused their low expected genetic diversity. Microsatellite markers are well known as a suitable DNA marker for exploring genetic diversity among captive populations of a variety of endangered species. In the present study, ten microsatellite markers were developed for the captive populations of the South Korean crested ibis, which were employed to examine the level of genetic diversity with the two founders from Sanxii, China and the 70 descendants of them. As a result, the mean number of gene diversity, observed heterozygosity, and expected heterozygosity of the captive population were 0.70, 0.84, and 0.70 respectively. It revealed that the captive population of South Korea is as genetically more stable than we expected. In addition, the principal coordinates analysis and genetic structure analyses showed that the captive population of N. nippon can be divided into the two different genetic groups. The developed microsatellite markers here could be helpful for crested ibis conservation in East Asian countries such as China and Japan as well as South Korea.

The domestication event of the Tibetan pig revealed to be in the upstream region of the Yellow River based on the mtDNA D-loop

  • Ge, Qianyun;Gao, Caixia;Cai, Yuan;Jiao, Ting;Quan, Jinqiang;Guo, Yongbo;Zheng, Wangshan;Zhao, Shengguo
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.4
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    • pp.531-538
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    • 2020
  • Objective: Evidence from previous reports indicates that pig domestication in East Asia mainly occurred in the Mekong region and the middle and downstream regions of the Yangtze River. Further research identified two new origin centers for domestic pigs in the Tibetan Plateau and the islands of Southeast Asia. However, due to the small sample size of Tibetan pigs, details of the origin and spread of Tibetan pigs has not yet been established. Methods: We analyzed mitochondrial DNA control region (D-loop) variation in 1,201 individuals from nine Tibetan pig populations across five provinces. Comprehensive Tibetan pig samples were taken to perform the most detailed analysis of Tibetan pigs to date. Results: The result indicate that Rkaze pigs had the lowest level of diversity, while Changdu pigs had the highest diversity. Interestingly, these two populations were both in the Tibetan Plateau area. If we calculate diversity in terms of each province, the Tibetan Plateau area had the lowest diversity, while the Chinese province of Gansu had the highest diversity. Diversity gradient analysis of major haplotypes suggested three domestication centers of Tibetan pigs in the Tibetan Plateau and the Chinese provinces of Gansu and Yunnan. Conclusion: We found two new domestication centers for Tibetan pigs. One is in the Chinese province of Gansu, which lies in the upstream region of the Yellow River, and the other is in the Chinese province of Yunnan.

Diversity of Spider Communities in a Pesticide-treated Pine (Pinus densiflora) Forest

  • Park, Yung-Chul;Yoo, Jung-Sun;Kim, Joo-Pil
    • Journal of Ecology and Environment
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    • v.30 no.2
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    • pp.179-186
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    • 2007
  • The diversity of spider communities was investigated in the pine forest of Pinus densiflora in Songri-san, where chemical pesticides had been applied to control pine gall midge (Thecodiplosis japonensis). Spider communities were surveyed in four areas: a pesticide-untreated natural forest (area A), a forest with vinyl-covered ground surface (area B), an aldicarb-treated forest (area C) and a forest treated with a systemic pesticide (phosphamidon) (area D). A total of 74 spider species from 17 families were collected from the four survey areas. There were 54 species from 15 families in area A, 27 species from 12 families in area B, 29 species from 9 families in area C and 34 species from 9 families in area D, respectively. The species diversity of spider communities was highest in pesticide-untreated area A, and much lower in the other three areas. The monthly species diversity of spider communities was highest in May and lowest in January. The similarity of the spider communities was highest in areas B and D. The monthly similarity of the spider communities was highest in November and February. The dominant species was Clubiona jucunda (12.71%, N=304 individuals). According to our results, the application of aldicarb and phosphamidon dramatically decreased spider diversity and the number of individuals in the forests. Thus, the application of these two pesticides to natural forests should be restricted, or alternative pesticides need to be developed. Our results also indicated that application of the pesticides should be avoided in May and June when high spider diversity is expected.

How Are the Direction and the Intensity of Indirect Social Information such as Likes and Dislikes Related to the Deliberative Quality of Online News Content Comments? A Topic Diversity Analysis Using Topic Modeling ('좋아요'와 '싫어요'같은 간접적 사회적 정보의 방향과 강도는 온라인 뉴스 콘텐츠 댓글의 숙의의 질과 어떤 관련이 있는가? 토픽 모델링을 이용한 토픽 다양성 분석)

  • Min, Jin Young;Lee, Ae Ri
    • The Journal of Information Systems
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    • v.30 no.4
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    • pp.303-327
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    • 2021
  • Purpose The online comments on news content have become social information and are understood based on deliberative democracy. Although the related research has focused on the relationship between online comments and their deliberative quality, the social information provided by online comments consists of not only direct information such as comments themselves but also indirect information such as 'likes' and 'dislikes'. Therefore, the research on online comments and deliberative quality should study this direct and indirect information together, and the direction and the degree of the indirect information should be also considered with them. Design/methodology/approach This study distinguishes comments by the attached 'likes' and 'dislikes', identifies highly supported and highly unsupported comments by the intensity of 'likes' and 'dislikes', and investigates the relationship between their existence and the deliberative quality measured as the topic diversity. Then, we applied topic modeling to the 2,390 news articles and their 74,385 comments collected from five news sites. Findings The topic diversities of the supported and unsupported comments are related to the topic diversity of all comments but the degree of the relationship is higher in the case of supported comments. Furthermore, the existence of highly supported and unsupported comments is led to less diversity of all comments compared to the case where those comments are absent. Particularly, when only highly supported comments are present, topic diversity was lower than in the opposite case.