• Title/Summary/Keyword: local diversity

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Phenotypic diversity, major genes and production potential of local chickens and guinea fowl in Tamale, northern Ghana

  • Brown, Michael Mensah;Alenyorege, Benjamin;Teye, Gabriel Ayum;Roessler, Regina
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.10
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    • pp.1372-1381
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    • 2017
  • Objective: Our study provides information on phenotypes of local chickens and guinea fowl and their body measures as well as on major genes in local chickens in northern Ghana. Methods: Qualitative and morphometric traits were recorded on 788 local chickens and 394 guinea fowl in urban households in Tamale, Ghana. Results: The results showed considerable variation of color traits and numerous major genes in local chickens, while color variations and related genotypes in guinea fowl were limited. In local chickens, white was preferred for plumage, whereas dark colors were preferred for beak and shanks. More than half of the chickens carried at least one major gene, but the contributions of single gene carriers were low. All calculated allele frequencies were significantly lower than their expected Mendelian allele frequencies. We observed higher mean body weight and larger linear body measures in male as compared to female chickens. In female chickens, we detected a small effect of major genes on body weight and chest circumference. In addition, we found some association between feather type and plumage color. In guinea fowl, seven distinct plumage colors were observed, of which pearl grey pied and pearl grey were the most prevalent. Male pearl grey pied guinea fowl were inferior to pearl grey and white guinea fowl in terms of body weight, body length and chest circumference; their shank length was lower than that of pearl grey fowl. Conclusion: Considerable variation in qualitative traits of local chickens may be indicative of genetic diversity within local chicken populations, but major genes were rare. In contrast, phenotypic and genetic diversity in local guinea fowl is limited. Broader genetic diversity studies and evaluation of trait preferences of local poultry producers are required for the design of appropriate breeding programs.

Longitudinal Variation of Fish Communities in the Geum River, Korea: Application of the Concept of Beta Diversity and Local Uniqueness

  • Kim, Jeong-Hui;Park, Sang-Hyeon;Baek, Seung-Ho;Hong, Donghyun;Jo, Hyunbin
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.3 no.2
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    • pp.122-128
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    • 2022
  • To present the spatial variation of fish assemblages in the Geum River in Korea, the concept of beta diversity (β-diversity) estimates based on the variance of the community data table was applied. Fish communities and environmental variables were collected from 13 sampling sites along the in mid-low reaches of the River. We calculated the β-diversity and local contribution to beta diversity (LCBD) values at each site depending on the two types of data, 'occurrence' with Jaccard and Sørensen dissimilarity coefficients, and 'abundance' with Hellinger distance. Multivariate and correlation analyses were also performed to determine the relationships between LCBD and other variables, such as community indices and physicochemical and hydrological factors. The β-diversity values of fish communities in the River were estimated as 0.218 and 0.145 for occurrence data table with Jaccard and Sørensen respectively, and 0.268 for abundance data. Similar patterns of LCBD along the sampling sites were detected in two dissimilarity measurements of occurrence table, and LCBD values with abundance data were slightly different. The LCBD values are strongly correlated with community indices, and also suitable for indicating the uniqueness of fish assemblages. However, further research is needed to determine the LCBD value as an indicator of environmental variability.

Comparing Plant Species Diversity of Mountainous Deserts - Successes and Pitfalls

  • Van Etten, Eddie J.B.
    • The Korean Journal of Ecology
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    • v.27 no.2
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    • pp.79-86
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    • 2004
  • An extensive study of the vegetation characteristics of the Hamersley Ranges, a mountainous desert area of north-west Australia, facilitated the comparison of plant species diversity measures with mountainous deserts of other parts of the world. Alpha diversity was defined as the number of species co-existing at local scales and was found to average 18 species per 0.1 ha for the Hamersley Ranges. This was found to be similar to seven other mountainous deserts in North and South America, and southern Africa. Variation in alpha diversity between these deserts was found to considerably lower than within deserts, suggesting that local processes control species richness at local scales. Beta diversity, defined here as turnover in species composition at various spatial scales, can be measured in many ways. For the Hamersley Ranges, Wilson's β ranged from 1.2 to 1.6 for five sites along a topographic gradient, whereas Whittaker's β between different plant communities was found to average 0.93. Comparable data was not found for other desert areas, but comparisons to non-desert areas suggest beta diversity within landscapes is relatively high and is likely to reflect the considerable landform heterogeneity of the Hamersley Ranges. 55∼70% of species were shared between different landscapes of the Hamersley Ranges; comparisons to other regions suggest beta diversity at this scale is relatively low. Gamma diversity, the number of species over large spatial extents, was successfully compared using regression analysis of the log-log species - area relationship. This revealed that the northern Sonoran desert has significantly less species than the Nama (inland) Karoo and Hamersley Ranges over medium spatial extents, but species numbers were similar at a regional scale. Several constraints to the valid comparison of species diversity were identified, including lack of standardisation of sampling techniques, the wide range of measures employed, general lack of published data, and the influence of the various components of spatial scale on most diversity measures. Recommendations on how to improve future comparative work are provided.

On Sweeping Operators for Reducing Premature Convergence of Genetic Algorithms (유전 알고리즘의 조기수렴 저감을 위한 연산자 소인방법 연구)

  • Lee, Hong-Kyu
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.12
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    • pp.1210-1218
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    • 2011
  • GA (Genetic Algorithms) are efficient for searching for global optima but may have some problems such as premature convergence, convergence to local extremum and divergence. These phenomena are related to the evolutionary operators. As population diversity converges to low value, the search ability of a GA decreases and premature convergence or converging to local extremum may occur but population diversity converges to high value, then genetic algorithm may diverge. To guarantee that genetic algorithms converge to the global optima, the genetic operators should be chosen properly. In this paper, we analyze the effects of the selection operator, crossover operator, and mutation operator on convergence properties, and propose the sweeping method of mutation probability and elitist propagation rate to maintain the diversity of the GA's population for getting out of the premature convergence. Results of simulation studies verify the feasibility of using these sweeping operators to avoid premature convergence and convergence to local extrema.

The effects of the Store attributes and Relationship quality on the Conversion intent of fashion store -Focused on Internet shopping mall and Local store- (의류점포속성 및 관계품질이 점포전환의도에 미치는 영향에 관한 연구 - 인터넷 쇼핑몰과 재래시장 패션전문상가를 중심으로 -)

  • Chung, Young-Ju;Jang, Eun-Young
    • Journal of Fashion Business
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    • v.16 no.4
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    • pp.75-87
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    • 2012
  • This study was to investigate the conversion intent of fashion store among college undergraduates. The conversion intent in internet shopping mall and local store was associated with store attributes and relationship quality. A random sample of undergraduate students completed a questionnaire that contained measure of Store attributes, Relationship quality, Conversion intent of fashion store. The results revealed that store attributes of local store were store comport/salesman service, product diversity, store location, price and the store attributes of internet shopping mall were product diversity/easy of navigation, store reliability, screen configuration, sales promotion. Also, the result founded that the conversion intent of fashion store is related to store comport/salesman service in local store and is related to product diversity/easy of navigation, screen configuration, promotion in internet shopping mall. Relationship quality is highly effected of the conversion intent of local store and internet shopping mall. We expect that this research results can be used as a basic material for another study and setting up the marketing strategies in fashion store.

Latitudinal Variation of the Number of Species and Species Diversity in Shelled Gastropods of Eastern Coast of Korea (위도구배에 따른 한국 동해안 암반조하대 복족류의 출현 종 수 및 종다양성 변이)

  • Son, Min-Ho;Lee, Jeong-Woo;Moon, Chang-Ho;Kim, Sung;Chun, Chan-Kil
    • The Korean Journal of Malacology
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    • v.20 no.2
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    • pp.159-164
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    • 2004
  • In the present study we examined latitudinal trend of the number of species and species diversity of rocky subtidal shelled gastropods. Specimens were sampled from four wave-exposed sites along the eastern coast of Korea between Sockcho (38$^{\circ}$14"N_ and Busan (35$^{\circ}$06"N), covering a range of over ca. 440 km and 4$^{\circ}$ of latitude. At a small local scale, the number of species showed a latitudinal trend, decreased with decreasing of latitude, even though no clear trends in species diversity were detected. The present result, consequently, suggest that regulation of small-scale local diversity presumably results from the difference of the local micro-environment.

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Application of Beta Diversity to Analysis the Fish Community Structure in Stream (베타다양성 개념의 적용을 통한 청계천 어류 군집 특성 분석)

  • Kim, Dong-Hwan;Lee, Wan-Ok;Hong, Yang-Ki;Jeon, Hyoung-Joo;Kim, Kyung-Hwan;Kang, Hyejin;Song, Mi-Young
    • Korean Journal of Ecology and Environment
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    • v.52 no.3
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    • pp.274-283
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    • 2019
  • Beta diversity is an efficient means of assessing the spatial variation in community composition among sites. To present fish community variation and LCBD (Local Contribution to Beta Diversity) among sites in stream, 6 sampling sites were selected in Cheonggye stream. Fish communities, environmental and habitat variables were collected at sites from April 2014 to October 2015. We used the total variance of the fish community data table (site-by-species community table) based on different forms, presence-absence, abundance, and Hellinger transformation, to estimate and compare beta diversity and LCBD. Fish community data table transformed by Hellinger distance showed the higher values of beta diversity than presence-absence and abundance data table. A similar patterns of LCBD were observed with presence-absence and Hellinger transformed data table. Low value of beta diversity calculated by community data table with abundance was due to the non-normality of fish assemblage data. Additionally, correlation coefficients were calculated to evaluate the relationships among LCBD, community indices and physicochemical variables. LCBD showed negative correlation coefficients with Shannon diversity. Overall, application of beta diversity analysis is an efficient method of addressing spatial variation of fish communities and ecological uniqueness of the sites in stream.

Genetic Diversity Measures of 8 Local Sheep Breeds in Northwest of China for Genetic Resource Conservation

  • Zeng, X.C.;Chen, H.Y.;Hui, W.Q.;Jia, B.;Du, Y.C.;Tian, Y.Z.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.12
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    • pp.1552-1556
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    • 2010
  • The aim of this study was to evaluate, through the use of microsatellite markers, the current genetic diversity and the relationships of 375 individuals from 8 local sheep breeds reared in typical breeding farms in the northwest of China, and moreover, to offer a contribution towards genetic conservation decisions for the studied breeds. The expected heterozygosities and allelic richness for the 8 breeds varied from 0.474 to 0.623 and from 3.8 to 5.4, respectively. All the populations showed a significant deficit in heterozygosity and a relatively low level of genetic diversity. Furthermore, the high positive FIS value (ranging from 0.255 to 0.556) indicated inbreeding to be one of the main causes for high genetic homogeneity and lack of heterozygosity in all breeds. The clustering analysis performed with the DISPAN package showed that Aletai, Kazak, Bashibai and Bayinbuluke were grouped together, and Hetian, Qira black and Duolang were grouped together, which indicated that the relationship among breeds displayed some degree of consistency with their geographical distribution, production and origin. These findings indicate that improved conservation measures must be undertaken to avoid further losses of genetic diversity and minimize inbreeding represented by these breeds.

Genetic diversity and phylogenetic relationship analyzed by microsatellite markers in eight Indonesian local duck populations

  • Hariyono, Dwi Nur Happy;Maharani, Dyah;Cho, Sunghyun;Manjula, Prabuddha;Seo, Dongwon;Choi, Nuri;Sidadolog, Jafendi Hasoloan Purba;Lee, Jun-Heon
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.1
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    • pp.31-37
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    • 2019
  • Objective: At least eight local duck breeds have been recognized and documented as national germplasm of Indonesia so far. It is necessary to genetically characterize the local duck breeds for aiding conservation and future improvement strategies. Thus, this study was carried out to assess genetic diversity and phylogenetic relationship of eight local duck populations of Indonesia using microsatellite markers. Methods: In total, 240 individuals (30 individuals each population) from Alabio (AL), Bayang (BY), Magelang (MG), Mojosari (MJ), Pegagan (PG), Pitalah (PT), Rambon (RM), and Turi (TR) duck populations were genotyped using 22 microsatellite markers. Results: The results showed a moderate level of genetic diversity among populations, with a total of 153 alleles detected over all loci and populations, ranging from 3 to 22 alleles per locus. Observed (Ho) and expected heterozygosity (He), as well as polymorphism information content over all loci and populations were 0.440, 0.566, and 0.513, respectively. Heterozygote deficiency in the overall populations ($F_{IT}=0.237$), was partly due to the heterozygote deficiency within populations ($F_{IS}=0.114$) and moderate level of genetic differentiation among populations ($F_{ST}=0.137$). The most diverse population was MG (He = 0.545) and the least diverse population was AL (He = 0.368). The majority of populations were relatively in heterozygote deficiency (except AL), due to inbreeding. The genetic distances, phylogenetic trees, and principal coordinates analysis concluded that the populations can be grouped into two major clusters, resulting AL, MG, and MJ in one cluster separated from the remaining populations. Conclusion: The present study revealed a considerable genetic diversity of studied populations and thus, proper management strategies should be applied to preserve genetic diversity and prevent loss of alleles.

Genetic Variability Comparison of Wild and Cultured Far Eastern Catfish (Silurus asotus) of Korea using Microsatellite Marker

  • Kim, Jung Eun;Hwang, Ju-Ae;Kim, Hyeong Su;Lee, Jeong-Ho
    • Development and Reproduction
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    • v.24 no.4
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    • pp.317-325
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    • 2020
  • The Far Eastern catfish (Silurus asotus) is an important commercial freshwater fish in Korea. Investigation of the genetic diversity of wild and cultured domestic catfish groups is essential for the restoration of fishery resources and for increasing local revenue. However, there are relatively few genetic diversity studies on wild and cultured catfish in Korea. In the present study, we analyzed the genetic diversity and association of wild and cultured catfish using five microsatellite markers. We determined that the number of alleles per locus (NA) ranged from 9 to 25, wherein the Jeonbuk catfish demonstrated the highest mean number of alleles per locus and the cultured catfish exhibited the lowest. The average expected heterozygosity (He) of the wild catfish samples was 0.907, and that of the cultured catfish showed was 0.875. The genetic distances (GD value) among populations of all catfish ranged from 0.138 to 0.242. Jeonnam and Jeonbuk wild catfish were located closest to each other, and the cultured group was separated from the other groups. In conclusion, the present study confirmed that the genetic diversity of wild and cultured catfish was maintained at a high level. In the case of the wild group, it is effective in maintaining diversity due to the continuous fry release by the local fish research institute. However, the genetic diversity of cultured catfish declined. Low diversity is associated with slow growth and weakened immunity, and therefore continuous monitoring is necessary.