• Title/Summary/Keyword: Selection Diversity

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Secondary human impacts on the forest understory of Ulleung Island, South Korea, a temperate island

  • Andersen, Desiree
    • Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.202-211
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    • 2019
  • Oceanic islands are biologically important for their unique assemblages of species and high levels of endemism and are sensitive to environmental change because of their isolation and small species source pools. Habitat destruction caused by human landscape development is generally accepted as the main cause of extinction on islands, with exotic species invasion a secondary cause of extinction, especially on tropical islands. However, secondary impacts of human development (e.g., general degradation through resource use and exotic species introduction) are understudied on temperate islands. To determine secondary impacts of human development on the understory vegetation community, 90 field sites on Ulleung Island, South Korea, were sampled during the summer of 2016. Understory vegetation was chosen as it is a proxy for ecosystem health. Diversity and percent cover of introduced, native, and endemic species were tested against proximity to developed areas and trail usage using a model selection approach. Diversity was also tested against percent cover of three naturalized species commonly found in survey plots. The main finding was that distance to development, distance to town, and trail usage have limited negative impacts on the understory vegetation community within best-supported models predicting native and introduced cover and diversity. However, endemic species cover was significantly lower on high usage trails. While there are no apparent locally invasive plant species on the island at the time of this study, percent cover of Robinia pseudoacacia, a naturalized tree species, negatively correlated with plot diversity. These findings indicate that forests on Ulleung Island are not experiencing a noticeable invasion of understory vegetation, and conservation efforts can be best spent preventing future invasions.

Analysis on Characteristics of Agricultural Heritage in GIAHS sites (세계중요농업유산(GIAHS) 등재지역 농업유산의 특성 분석)

  • Jeong, Myeong-Cheol;Mun, Hyo-Yun;Yoon, Soon-Duck;Kim, Sang-Bum
    • Journal of Korean Society of Rural Planning
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    • v.22 no.4
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    • pp.171-182
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    • 2016
  • Since FAO introduced the Globally Important Agricultural Heritage Systems(GIAHS) in 2002, 36 sites of 15 countries so far have been listed on GIAHS. This study aims to find the important agricultural heritages of Korea and to prepare the methods for them to be selected as GIAHS. We have analyzed the proposals of the 36 GIAHS listed in order to study the characteristics of their components of the agricultural heritage which worked for being selected. To analyze the components of the agricultural heritage first, agricultural heritage was classified into 13 types and 42 components in light of GIAHS criteria. Then central themes were set to analyze the relevant contents in the proposals. They were, the type of GIAHS Site, significant agricultural landscape, the agriculture-forestry-fisheries-livestock linkage systems, the multi-layered, inter-cropping, circulation cultivation systems, the soil and water management systems, the conservation of agrobiological diversity and genetic resources, the history of the agricultural heritage, the succession of traditional farming techniques, the cultural diversity and so on. Most GIAHS are located in mountains, grasslands, rivers and coasts, desert than in plains, through which GIAHS assure us that it is the heritage of human challenge to overcome the harsh geographic environment and maintain a livelihood. In these sites the traditional farming techniques are carried on, such as mountain clearings, terraced rice paddies, and burn fields, and the unique irrigation systems and agricultural landscapes are well maintained, and the eco-friendly traditional farming techniques utilizing abundant forest resources and agriculture are well handed down. The origin or home of crop growing, a variety of genetic crop storage, the world's largest crop producer and preserving cultural diversity are also important factors for the selection.

In vitro Evaluation of Different Feeds for Their Potential to Generate Methane and Change Methanogen Diversity

  • Kim, Seon-Ho;Mamuad, Lovelia L.;Jeong, Chang-Dae;Choi, Yeon-Jae;Lee, Sung Sill;Ko, Jong-Youl;Lee, Sang-Suk
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.12
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    • pp.1698-1707
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    • 2013
  • Optimization of the dietary formulation is the most effective way to reduce methane. Nineteen feed ingredients (brans, vegetable proteins, and grains) were evaluated for their potential to generate methane and change methanogen diversity using an in vitro ruminal fermentation technique. Feed formulations categorized into high, medium and low production based on methane production of each ingredient were then subjected to in vitro fermentation to determine the real methane production and their effects on digestibility. Methanogen diversity among low, medium and high-methane producing groups was analyzed by PCR-DGGE. The highest methane production was observed in Korean wheat bran, soybean and perilla meals, and wheat and maize of brans, vegetable protein and cereal groups, respectively. On the other hand, corn bran, cotton seed meal and barley led to the lowest production in the same groups. Nine bacteria and 18 methanogen 16s rDNA PCR-DGGE dominant bands were identified with 83% to 99% and 92% to 100% similarity, respectively. Overall, the results of this study showed that methane emissions from ruminants can be mitigated through proper selection of feed ingredients to be used in the formulation of diets.

A Study on the Evaluation of Value Indicator and Importance of Prototype Landscape in Rural Areas (농촌 원형경관의 문화재적 가치 속성 및 중요도 연구)

  • Kang, Young-Eun;Choi, Dong-Wook;Hong, Sung-Hee;Min, Su-Hui;Kim, Sang-Bum;Im, Seung-Bin
    • Journal of Korean Society of Rural Planning
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    • v.16 no.4
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    • pp.117-129
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    • 2010
  • This study is to make value estimating system to valuate prototype landscape of rural and to derive itemized importance to select priority preservable object The results of the study are summarized as follows, It is examined value estimating standard by analyzing prototype landscape related previous study, law and order. Also, It is derived conclusive prototype landscape value estimating system by doing attribute assessment of preserving objects while surveying the site and interviewing professionals, Value estimating system is classified into five items of physical value which are integration, harmony, diversity, symbolism and aesthetics, The historical-cultural value are divided into four categories which are religious value, originality, historicity and scarcity, The communal values are divided into three categories which are sociality, continuing and regional locality and also divided into three categories which are rarity, primitiveness and diversity as the ecological value, Relative priority of prototype landscape value estimating system result is derived as historical-cultural value as the superior position and physical value, communal value and ecological value as the priority order. In the subordinate, historical categories are derived to be the most valuable and originality, symbolism, integration, regional locality, continuing, harmony, aesthetics, religious value, primitiveness, diversity of physical values and diversity of ecological value in order of the priority assessment The results of the study have the meaning of practical use in prior selection and preservation plan of preserving prototype landscape as practical alternative plan for systematical preservation of damaging prototype landscape.

Assessment of genetic diversity and phylogenetic relationship of Limousin herds in Hungary using microsatellite markers

  • Szucs, Marton;Szabo, Ferenc;Ban, Beata;Jozsa, Csilla;Rozsa, Laszlo;Zsolnai, Attila;Anton, Istvan
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.2
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    • pp.176-182
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    • 2019
  • Objective: This study was conducted to investigate basic information on genetic structure and characteristics of Limousin population in Hungary. Obtained results will be taken into consideration when adopting the new breeding strategy by the Association of Hungarian Limousin and Blonde d'Aquitaine Breeders (AHLBB). Methods: Genetic diversity and phylogenetic relationship of 3,443 Limousin cattle from 16 different herds were investigated by performing genotyping using 18 microsatellite markers. Amplified DNA was genotyped using an automated genetic analyzer. Results: Mean of effective alleles ($n_e$) of the populations was 3.77. Population C had the lowest number of effective alleles (3.01) and the lowest inbreeding coefficient ($F_{IS}$) value (-0.15). Principal component analysis of estimated genetic distance ($F_{ST}$) values (p<0.000) revealed two herds (C and E) distinct from the majority of other Limousin herds. The pairwise $F_{ST}$ values of population C compared to the others (0.066 to 0.120) fell into the range of moderate genetic distance: 0.050 to 0.150, while population E displayed also moderate genetic distance ($F_{ST}$ values in range 0.052 to 0.064) but only to six populations (G, H, J, L, N, and P). $F_{ST(C-E)}$ was 0.148, all other pairs -excluding C and E herds- displayed low genetic distance ($F_{ST}$<0.049). Population D, F, I, J, K, L, N, O, and P carried private alleles, which alleles belonged to 1.1% of the individuals. Most probable number of clusters (K) were 2 and 7 determined by Structure and BAPS software. Conclusion: This study showed useful genetic diversity and phylogenetic relationship data that can be utilized for the development of a new breeding strategy by AHLBB. The results presented could also contribute to the proper selection of animals for further whole genome scan studies of Limousins.

Coarse-to-fine Classifier Ensemble Selection using Clustering and Genetic Algorithms (군집화와 유전 알고리즘을 이용한 거친-섬세한 분류기 앙상블 선택)

  • Kim, Young-Won;Oh, Il-Seok
    • Journal of KIISE:Software and Applications
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    • v.34 no.9
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    • pp.857-868
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    • 2007
  • The good classifier ensemble should have a high complementarity among classifiers in order to produce a high recognition rate and its size is small in order to be efficient. This paper proposes a classifier ensemble selection algorithm with coarse-to-fine stages. for the algorithm to be successful, the original classifier pool should be sufficiently diverse. This paper produces a large classifier pool by combining several different classification algorithms and lots of feature subsets. The aim of the coarse selection is to reduce the size of classifier pool with little sacrifice of recognition performance. The fine selection finds near-optimal ensemble using genetic algorithms. A hybrid genetic algorithm with improved searching capability is also proposed. The experimentation uses the worldwide handwritten numeral databases. The results showed that the proposed algorithm is superior to the conventional ones.

Efficient Transmit Antenna Selection Method for Massive MIMO system (Massive MIMO 시스템을 위한 효율적인 송신 안테나 선택 기법)

  • Ju, Sang-Lim;Lee, Byung-Jin;Kim, Young-Jae;Kim, Jin-Up;Bang, Young-Jo;Kim, Kyungseok
    • Journal of Satellite, Information and Communications
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    • v.11 no.3
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    • pp.58-64
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    • 2016
  • This paper proposes the efficient transmit antenna selection (TAS) scheme considering trade-off between the performance and the complexity in massive MIMO system. The massive MIMO system is a core technology to achieve performance objectives for 5 generation wireless communication. It achieve high spectral efficiency, a reliability, and a diversity gain. However many RF chains required by massive transmit antennas equipped in a base station create the problem such as high hardware cost and complexity. Therefor we investigates the transmit antenna selection scheme, in which the number of RF chains of BS is reduced, and the trade-off between the performance and the complexity is considered for proposed scheme. And, the spectral efficiency and complexity are analysed by transmit antenna selection schemes.

A Study on the Influence of Menu Selection Attributes and Design of Western Restaurants on the Customer Value and Customer Satisfaction (양식레스토랑의 메뉴선택속성과 디자인이 고객가치, 고객만족에 미치는 영향에 관한 연구)

  • Jung, Jin-Woo
    • Culinary science and hospitality research
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    • v.20 no.6
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    • pp.69-79
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    • 2014
  • How the menu selection attributes and menu design attributes influence the customer value and customer satisfaction is a major study object. In order to achieve the purpose of this study, a questionnaire survey was conducted to the consumers of 4 Western restaurants. Selecting 223 copies, the diversity of menu and convincibility of menu turned out to be influential on the customer value. In the Hypothesis 2, menu selection attributes turned out to be influential on the customer satisfaction. In the Hypothesis 3, menu design turned out to be influential on the customer value. In the Hypothesis 4, menu design turned out to be influential on the customer satisfaction. In the Hypothesis 5, the customer value turned out to be influential on the customer satisfaction. The study shows that the importance of menu selection and menu design is a significant in regards to customer value and customer satisfaction.

Relay Selection Schemes Using STBC Technique in OFDM-Based Cooperative Wireless Communications (OFDM 기반의 무선 협력 통신에서 STBC 기술을 적용한 선택적 릴레이 통신 기법)

  • Lee, Je-Yeon;Yang, Mo-Chan;Yoo, Sung-Cheol;Shin, Yo-An
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.7A
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    • pp.640-648
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    • 2011
  • We propose relay selection schemes using STBC (Space Time Block Coding) technique in OFDM (Orthogonal Frequency Division Multiplexing)-based wireless systems. The proposed schemes select the optimum relay having the maximum instantaneous equivalent channel gain among multiple candidate relays. Also, in order to reduce the system overhead, a symbol grouping method which groups some amount of symbols before selecting the optimum relay is proposed. The simulation results show that the proposed relay selection schemes can obtain more selection diversity gain as the number of selectable relay candidates increases. Furthermore, the proposed scheme with the symbol grouping can reduce system overhead without any degradation of the performance in fading channels with low frequency selectivity.

Estimation of Genetic Parameters and Improvements for Growth Traits of Selected Olive Flounder Paralichthys olivaceus (선발육종 넙치(Paralichthys olivaceus)의 성장형질에 대한 유전모수 및 유전적 개량효과 추정)

  • Park, Jong-Won;Lee, Da-In;Jung, Hyo Sun;Kim, Julan;Yang, He-Rim;Lee, Jeong-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.54 no.6
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    • pp.974-981
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    • 2021
  • The aim of this study was to evaluate genetic parameters of growth traits for improving selective breeding in olive flounder Paralichthys olivaceus produced in April 2019. The total length and body weight at 11-, 18-, and 22-months-old were measured for 7,479, 2,831 and 1,904 individuals, respectively. Since 2004, we have been conducting a selective breeding program to improve growth traits in the olive flounder. Data were analyzed using the restricted maximum likelihood method using the multiple traits animal model. The effect of sex and production period showed significant differences in all traits (P<0.05). The heritability of all traits was 0.428-0.520, which is relatively high by measurement month. Therefore, it is considered that individual selection will be more advantageous than family selection. However, to maintain an appropriate degree of inbreeding and genetic diversity for future generations, it is necessary to consider family selection adequately. Results of the correlation analysis between the same traits according to the measurement period indicated that considering production costs such as feed cost, selection at 18-months-old will be advantageous. Olive flounder is a major aquaculture species in Korea, and continuous selective breeding research is essential to improve productivity.