• Journal of Ecology and Environment
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• 제43권4호
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• pp.454-461
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• 2019

Background: Ikonnikov's whiskered bat (Myotis ikonnikovi) is found throughout the Korean Peninsula, as well as in Kazakhstan, Russia, Mongolia, China, and Japan. It is small-sized and primarily inhabits old-growth forests. The decrease and fragmentation of habitats due to increased human activity may influence the genetic structure of bat populations. This study was designed to elucidate the population genetic structure of M. ikonnikovi using mitochondrial genes (cytochrome oxidase I and cytochrome b). Results: The results showed that M. ikonnikovi populations from Korea have high genetic diversity. Although genetic differentiation was not detected for the COI gene, strong genetic differentiation of the Cytb gene between Mt. Jeombong and Mt. Jiri populations was observed. Moreover, the results indicated that the gene flow of the maternal lineage may be limited. Conclusions: This study is the first to identify the genetic population structure of M. ikonnikovi. We suggest that conservation of local populations is important for sustaining the genetic diversity of the bat, and comprehensive studies on factors causing habitat fragmentation are required.

• 한국육종학회지
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• 제42권1호
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• pp.11-22
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• 2010

The population structure of a domesticated species is influenced by the natural history of the populations of its pre-domesticated ancestors, as well as by the breeding system and complexity of breeding practices implemented by humans. In the genetic and population structure analysis of 122 South Asia collections using 29 simple sequence repeat (SSR) markers, 362 alleles were detected, with an average of 12.5 per locus. The average expected heterozygosity and polymorphism information content (PIC) for each SSR locus were 0.74 and 0.72,respectively. The model-based structure analysis revealed the presence of three clusters with the 91.8% (shared > 75%) membership, with 8.2% showing admixture. The genetic distances of Clusters 1-3 were 0.55, 0.56, and 0.68, respectively. Polymorphic information content followed the same trend (Cluster 3 had the highest value and Cluster 1 had smallest value), with genetic distances for each cluster of 0.52, 0.52, and 0.65, respectively. This result could be used for supporting rice breeding programs in South Asia countries.

• 한국패류학회지
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• 제24권2호
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• pp.81-87
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• 2008

Distribution, population structure, and growth of the bivalve Protothaca euglypta were investigated for clams collected from the northwestern part of the East Sea of Russia. This species is distributed in further northern area than it was found earlier. In the southern area, this clam is found in the intertidal zone, up to 8 m in depth. It is one of the most numerous infaunal species of bivalves, and protected to wave action in the gravel-pebble and sand with rubble biotope. Population density of P. euglypta reaches 500 $spc./m^2$, and biomass 2 $kg/m^2$. Size and age composition of the local settlements and allometric growth of P. euglypta depend on a biotope. The growth rate of P. euglypta considerably reduces in case of the northern boundary area, whereas life span increases.

• Journal of Species Research
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• 제1권1호
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• pp.100-103
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• 2012

Nutria Myocastor coypus is one of a well known invasive riparian mammal found species around world from North America to Eurasia and Africa. In South Korea, feral nutrias inhabit areas from the Nakdonggang and Namgang (River) to their tributaries and Upo Wetland where they have had devastating effects on environment. Nevertheless, there has been little research about nutrias in Korea. This study is to analyze the genetic structure of the nutria population in the Upo Wetland and identify the origin of the source populations. Twenty individuals from the Upo Wetland were genotyped using 25 microsatellite loci. When compared with another introduced population, that of the Blackwater Nation Wildlife Refuge in U.S., the Upo population contains considerable genetic variations. Tests for Hardy-Weinberg equilibrium and Bayesian clustering analysis suggest the Upo population is genetically structured and has at least two source populations. This preliminary study presents the need for further in-depth studies about this species which should combine genetic and ecological studies.

• 대한토목학회논문집
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• 제33권6호
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• pp.2583-2591
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• 2013

국내 많은 도시들은 경제 성장률 하락에 따른 고용창출 하락, 출산률 감소에 따른 인구감소, 노령인구 증가에 따른 도시활력 감소, 도심 공동화에 따른 도시기능 쇠퇴 등 20세기에 겪어보지 못한 새로운 도시양상에 직면하고 있다. 이에 따라 이들 도시들은 도시의 당면한 문제를 해결하고 도시 경쟁력을 향상 시킬 수 있는 다양한 방안 중 하나로 창조도시에 대한 관심이 높아지고 있다. 창조도시는 주민들이 다양한 문화생활과 여가활동이 가능하고 혁신적인 산업을 진흥할 수 있는 장소가 풍부한 도시로서 과학자, 기술자, 건축가, 디자이너, 작가, 예술가, 음악가 등의 창조산업 인구에 의해 선도된다. 따라서 본 연구는 국내 도시를 인구규모별로 구분하여 어떠한 도시구조가 창조산업 인구와 관계가 있는지를 제시하는데 목적이 있다. 연구결과 광역시에서는 문화행사 수가 창조산업 인구와 관계가 있으며 대도시에서도 문화행사 수와 문화공간 수가 창조산업 인구에 영향을 미치는 것으로 나타났다. 한편 중소도시에서는 문화행사 수와 환경오염 관리시설이 창조산업 인구 유인에 영향을 미치는 것으로 나타났다. 따라서 창조산업 인구 유입에 가장 큰 영향을 미치는 요소가 도시문화임에 따라 도시 경쟁력을 강화하기 위해서는 다양한 도시문화 환경을 조성하는 것이 시급하다.

• 한국지리정보학회지
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• 제17권4호
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• pp.167-178
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• 2014

수도권의 과도한 집중에 따른 부작용을 해소하고 국가 균형 발전 및 국가경제력 강화를 위하여 2012년 출범한 세종시는 대규모 택지개발이 급격한 개발속도로 이루어지면 주변지역 공간구조의 변화가 예상된다. 본 연구는 세종시 출범에 따른 인접지역의 공간구조 변화를 측정하기 위한 일환으로 공간적 상호작용 측면에서 접근하였다. 분석은 Accessibility 모델을 이용하여 미래 공간 상호작용을 위한 잠재력인 인구잠재력을 계산하고, 인구잠재력을 지표로 활용하여 공간패턴분석기법에 적용함으로써 세종시 건설 전후 인접지역들의 공간적 상호작용 결과를 정량적 정성적으로 해석하였다. 분석결과 1995년 이후 대상지역 인구잠재력의 영향범위는 지속적으로 감소하는 것으로 나타났으며, 2013년에는 천안시를 중심으로 인구가 집중하여 인구잠재력이 분산되는 것으로 나타났다. 세종시는 새로운 인구잠재력 지대로써 주변지역에 대한 구심점 역할을 수행하지 못하는 것으로 나타났지만 세종시의 입주가 얼마 지나지 않은 시점에서의 분석결과 때문으로 판단된다. 따라서 세종시의 계획인구 도달을 위한 노력과 함께 인구증가에 따른 요인들의 변화와 주변 도시들의 공간구조변화에 대한 지속적인 모니터링이 필요하다고 하겠다.

• Animal Bioscience
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• 제36권5호
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• pp.692-703
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• 2023

Objective: The main goals of this investigation were to i) assess the population structure and genetic diversity and ii) determine the efficiency of the ongoing breeding program in a closed flock of Angora rabbits through pedigree analysis. Methods: The pedigree records of 6,145 animals, born between 1996 to 2020 at NTRS, ICAR-CSWRI, Garsa were analyzed using ENDOG version 4.8 software package. The genealogical information, genetic conservation index and parameters based on gene origin probabilities were estimated. Results: Analysis revealed that, 99.09% of the kits had both parents recorded in the whole dataset. The completeness levels for the whole pedigree were 99.12%, 97.12%, 90.66%, 82.49%, and 74.11% for the 1st, 2nd, 3rd, 4th, and 5th generations, respectively, reflecting well-maintained pedigree records. The maximum inbreeding, average inbreeding and relatedness were 36.96%, 8.07%, and 15.82%, respectively. The mean maximum, mean equivalent and mean completed generations were 10.28, 7.91, and 5.51 with 0.85%, 1.19%, and 1.85% increase in inbreeding, respectively. The effective population size estimated from maximum, equivalent and complete generations were 58.50, 27.05, and 42.08, respectively. Only 1.51% of total mating was highly inbred. The effective population size computed via the individual increase in inbreeding was 42.83. The effective numbers of founders (f_e), ancestors (f_a), founder genomes (f_g) and non-founder genomes (f_ng) were 18, 16, 6.22, and 9.50, respectively. The fe/fa ratio was 1.12, indicating occasional bottlenecks had occurred in the population. The six most influential ancestors explained 50% of genes contributed to the gene pool. The average generation interval was 1.51 years and was longer for the sire-offspring pathway. The population lost 8% genetic diversity over time, however, considerable genetic variability still existed in the closed Angora population. Conclusion: This study provides important and practical insights to manage and maintain the genetic variability within the individual flock and the entire population.

• 한국식물학회:학술대회논문집
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• 한국식물학회 2001년도 춘계학술발표대회:발표눈문요지록
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• pp.18-18
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• 2001

• 한국인구학
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• 제16권2호
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• pp.1-23
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• 1993

Korea fertility level has dropped since the 1960's and speed of decline has accelerated in the 1980's. In the resuls, the growth rate reached to less then 1 percent in 1990 and will be $\ulcorner$0 $\lrcorner$ percent growth in 2021. The total population will increase to 50, 586 thousand persons in 2021 then will decrease. With the rapid fertility decline the age structure of Korean population has changed : while the proportion of child population aged 0-14 is decreasing sharply, that of old-age population aged 65 and over is increasing. Because of the recent increase of sex ratio at birth, the sex structure among the young generation has been destorted; the sex ratio at age 0-4 was as high as high as 112.0 in 1990. The effects of these population phenomena on Korean society are the followings: 1) Old age dependency ratio is increasing rapidly and continuously and will be about 40.0 from the 2050's. 2) Because of the rapid decline of the number of births, the absolute number of the major labour force at age 25-34 will decrease after around 2000 and then from the 2010's become less than that in 1990. 3) Since the large fertility defferentials by womens's educational level have continued and the relation between the educational levels of mothers and children are very strong, level has dropped among higher educated women first when the average fertility level has declined in Korea, the average educational level of the children is may be expected to be relatively low and then the future productivity is will be also low, which causes the decline of 'quality of population. 4) When the high sex ratio at birth (over 110 since 1986) continues, number of brides will be short by over 20 percent from the 2010s, which will bring various kinds of social prblems. Therefore, the counter measures in concrete to relieve the heavy problems are recommended as follows: 1) The extention of the birth intervals, which helps to drop the population growth rate at the same level of number of children per women. 2) The positive supports for out-migrants, which helps to reduce the population size without any destortion of age-sex structure. 3) The defferent supports of family planning for the higher and lower classes, which helps to reduce the gaps between different ferility levels of the classes and to keep and improve the quality of population. 4)population education for both students and adults, which helps to minimize the gap between the private and public requirements.

• Journal of Animal Science and Technology
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• 제62권6호
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• pp.790-800
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• 2020

The Yeonsan Ogye (YO) chicken is a natural heritage of Korea, characterized by black feathers, skin, bones, eyes, and comb. The purebred of YO population has been reared under the natural mating system with no systematic selection and breeding plan. The purpose of this study was to identify the genetic diversity and find the optimal number of population sub-division using 12 polymorphic microsatellite (MS) markers to construct a pedigree-based breeding plan for the YO population. A total of 509 YO birds were used for this study. Genetic diversity and population structure analysis were conducted based on the MS marker genotype information. The overall average polymorphic information content value and expected heterozygosity of the population were 0.586, and 0.642, respectively. The K-mean cluster analysis based on the genetic distance result confirmed that the current YO population can be divided into three ancestry groups. Individuals in each group were evaluated based on their genetic distance to identify the potential candidates for a future breeding plan. This study concludes that a future breeding plan with known pedigree information of selected founder animals, which holds high genetic diversity, could be the best strategy to ensure the conservation of the Korean YO chicken population.