• Title/Summary/Keyword: Similarity sampling

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Community Structure, Species Composition and Population Status of NTFPs of Ziro Valley in Arunachal Pradesh, India

  • Bamin, Yakang;Gajurel, Padma Raj;Paul, Ashish
    • Journal of Forest and Environmental Science
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    • v.33 no.3
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    • pp.202-225
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    • 2017
  • Non Timber Forest Products (NTFPs) has gained a lot of significance over the years as a means of income generation. Forests are playing a vital role in the supply of these products, however, due to their continuous extraction, the population of many species might have depleted. Very little information is known about community structure and population status of NTFPs. No specific studies have been made to find out the occurrence, availability of species and population status in the forests, supplying the resources. The present study has been carried out in community forests of the naturally occurring NTFPs in the temperate forest of the Ziro valley of Arunachal Pradesh. The main aim is to determine community structure, species composition and population status of NTFPs. Three forest stands viz., Nyilii, Dura and Gyachi were selected which are used by the Apatani tribe for extraction of the NTFPs. For evaluation of species composition and community characteristics, the sampling of the vegetation was done using the quadrat method. A total 137 species representing 68 families and 116 genera were recorded. Herbs represent the maximum diversity with 71 species followed by 35 shrub species and 31 tree species. The families Asteraceae and Rosaceaeae exhibited maximum representation followed by Urticaceae. The species under Fagaceae, Lauraceae, Rosaceae and Rutaceae were found to be important NTFP yielding species. Highest species richness was recorded in Nyilii having 124 species, while lowest in Dura with 102 species. Density of tree, shrub and herb ranged between 376 to $456\;individuals\;ha^{-1}$, 2848 to $3696\;individuals\;ha^{-1}$ and 31.44 to $36.64\;individuals\;m^{-2}$, respectively. The total basal area was found to be highest ($51.64m^2\;ha^{-1}$) in Dura followed by Nyilii ($25.32m^2\;ha^{-1}$) and lowest in Gyachi ($22.82m^2\;ha^{-1}$). In all the three study stands the species diversity indices showed the trend, herbs > shrubs > trees while the evenness index showed the trend as shrubs > herbs > trees. The overall species similarity index was highest (82.35%) between Dura and Gyachi. About 80% of the total recorded species showed clumped distribution while, no regular distribution was shown by any species. The three selected stands harbor about 50 important NTFP yielding species which are being used commonly by the Apatani people in their day to day life. Among the three study sites, overall diversity of NTFP was found highest in the Nyilii stand while the density of population was found better in Dura and Gyachi stands. The population of many species was found to be low due to continue harvesting without any sustainable management by the communities. All the selected forest stands have the potentiality to grow the high value NTFP yielding species and if managed properly, they can support the livelihood and economy of the local communities.

The Fish Fauna and Community of Chogang Stream, Korea (초강천의 어류상과 군집)

  • Hur, Jun-Wook;Park, Jin-Woo;Kim, Jeong-Kon
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.271-278
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    • 2010
  • Field monitoring was conducted for fish fauna and community assessment at 7 sites from April 2008 to October 2009 in the Chogang Stream. The number of fish samples in this period were 4,669 in 36 species of 9 families. Family Cyprinidae take 66.7 (24 species), Cobitidae, Bagridae, Centropomidae and Odontobutidae occupied 5.6%(each 2 species), respectively. Twenty species (55.6%) including Acheilognathus koreensis and A. yamatsutae were found endemic out of the 36 species. The species of Pseudopungtungia nigra, Gobiobotia macrocephala and Gobiobotia brevibarba were endangered species. The most frequently found one was Zacco koreanus (34.0%, n=1,588) followed by Z. platypus (22.6%, n=1,053) and Coreoleuciscus splendidus (13.3%, n=623). The lower reach of Chogang Stream was more abundance of species, high diversity, evenness and richness, and lower dominance index than those of the upper reach. According to the dendrogram established at 0.5 level of similarity rate, sampling stations were divided into 3 groups. They were divided into upper most stream (St. 1~St. 2), upper stream (St. 3), middle and lower stream (St. 4~St. 7). Overall, it was concluded that the Chogang Stream has been relatively well protected from the anthropogenic disturbance for the legally protected species including the endemic species studied in this study.

Community Structure of Fisheries Resources Caught by Dredge in the Uljin Marine Ranching Area, Korea (울진바다목장에서 형망으로 어획된 수산자원의 군집구조)

  • Yoon, Byoung Sun;Park, Jeong-Ho;Yoon, Sang Chul;Yang, Jae Hyeong;Sohn, Myoung Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.47 no.6
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    • pp.935-944
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    • 2014
  • To elucidate the variation of species composition, biomass and size distribution of fishery resource in the Uljin marine ranching area was investigated at the 4 stations from 2009 to 2010 based on the dredge sampling. During the survey period, a total of 41 fishery resource species were sampled with a mean density of $2,554,633\;ind./km^2$ and mean biomass was $32,946kg/km^2$. A total 36 fishery resource species were sampled with a mean density of $3,198,793\;ind./km^2$ and mean biomass $41,177kg/km^2$ in 2009 and it were sampled a total 31 species, mean $1,910,473kg/km^2$ and $24,716kg/km^2$ in 2010. The major individual-dominant species, occupying over 1% of total individuals, were Gomphina veneriformis (2,491,818 ind., 82.2%), Umbonium costatum (221,973 ind., 8.7%), Mactra chinensis (49,879 ind., 2.0%), Glossaulax didyma hayashii (49,879 ind., 1.9%), Blepharipoda liberate (37,714 ind., 1.5%) and Paguridae spp. (27,266 ind., 1.1%). The major biomass-dominant species, occupying over 1% of total biomass, were G. veneriformis (25,124 kg, 76.3%), G. didyma hayashii (2,596 kg, 7.9%), M. chinensis (2,024 kg, 6.1%), Ovalipes punctatus (921 kg, 2.8%) and Glossaulax didyma didyma (567 kg, 1.7%). From the cluster analysis based on Bray-Curtis similarity matrix of fourth root transformed data of species number and individuals was divided into 2 different groups of the fishery resource community (Group A-St.1, Group B-Sts. 2, 3, 4). The 2009 and 2010 mean Shell length (mm) of G. veneriformis was 37.73 mm, 29.76 mm and M. chinensis was 62.03 mm, 44.94 mm, respectively.

Study on applicability of fractal theory to cohesive sediment in small rivers (프랙탈 이론의 소하천 점착성 유사 적용에 관한 연구)

  • Lim, Byung Gu;Son, Minwoo
    • Journal of Korea Water Resources Association
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    • v.49 no.10
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    • pp.887-901
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    • 2016
  • Cohesive sediments form flocs through the flocculation process. The size and density of floc are variable whereas those of a fine sediment are always assumed to be constant. The settling velocity, one of main factors of sediment transport, is determined by size and density of particle. Therefore, the flocculation process plays an important role in transport of cohesive sediment. It is of great difficulty to directly measure the density of floc in the field due to technical limitation at present. It is a popular approach to estimate the density of floc by applying the fractal theory. The main assumption of fractal theory is the self-similarity. This study aims to examine the applicability of fractal theory to cohesive sediment in small rivers of Korea. Sampling sediment has been conducted in two different basins of Geum river and Yeongsan river. The results of settling experiments using commercial camera show that the sediment in Geum river basin follows the main concept of fractal theory whereas the sediment in Yeongsan river basin does not have a clear relationship between floc size and fractal dimension. It is known from this finding that the fractal theory is not easily applicable under the condition that the cohesive sediment includes the high content of organic matter.

Analysis of genetic diversity of cowpea landraces from Korea determined by Simple Sequence Repeats and establishment of a core collection

  • Lee, Jeongran;Baek, Hyung-Jin;Yoon, Mun-Sup;Park, Sang-Koo;Cho, Yang-Hee;Kim, Chang-Yung
    • Korean Journal of Breeding Science
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    • v.41 no.4
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    • pp.369-376
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    • 2009
  • Cowpea might have been introduced from China to Korea and cultivated for several hundred years but it has never been a staple food crop in Korea. In this study, genetic diversity of 492 Korean cowpea landrace accessions that have passport information was estimated using six SSR markers. The mean of Weir's gene diversity was 0.665 from all accessions investigated in the study. Cowpea gene diversity of six local provinces in Korea was ranged from 0.370 in accessions of Gangwon to 0.680 in Jeonra provinces. Low gene diversity of the cowpea genepool of Gangwon province was probably derived from relatively few introductions. Especially SSR markers VM36 and VM39 seem to be good markers to distinguish the Gangwon accessions from others by occurring at a specific locus with higher than 78% of allele frequency. Except for the Gangwon province with the low genetic diversity, gene diversity of cowpea accessions from other provinces was ranged from 0.600 to 0.680 indicating no big differences among provinces. Distribution pattern of the allele frequencies was similar among the other provinces. This may reveal that Korean farmers might exchange cowpea seeds easily with even their neighbors with geographical barriers. A core collection, 100 landraces, ca. 20% of base collection, was developed at the 70% of a similarity coefficient level using random sampling approaches after stratification of the entire landrace collection based on the phenetic dendrogram. The variability of SSR in the base and core collections of Korean cowpea landrace was compared by calculating Weir's gene diversity. The mean of Weir's gene diversity of the core was 0.707 while that of the base collection was 0.665. The higher diversity index in the core collection indicates that it maintains the initial variability and well represents the base collection. The core collection included one of determinate accession (IT 216155) and two of no branching type accessions (IT 103959 and IT 161024). The core collection could be used to guide more efficient management and utilization of the entire collection. This core collection should be revised periodically as additional accessions are collected and further characterization is conducted.

Exploration on the Strategies of Organizing Curriculum for Improvement of Major Basic Competencies in the Agricultural High School Students to University by Departments Identical to Their Major (농업계 고등학생들의 동일계 대학 전공기초능력 향상을 위한 교육과정 편성 방안 탐색)

  • Kim, Jin-Gu;Lee, Gun-Nam
    • Journal of vocational education research
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    • v.29 no.3
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    • pp.61-83
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    • 2010
  • The purpose of this study was to analyze high schools' general and special subject required to successfully complete same stream curriculum which is identical to their major from agricultural high school, and to offer basic data on strategies of organizing agricultural high schools' curriculum for improving universities' major basic competencies. Using purposeful sampling technique, the professors of 116 universities professors in 8 agricultural university were analyzed through the survey research. The result was as follows. first, it appeared that for successful completion of major subjects of the same stream university, the basic science subject such as biology and chemistry has high relation with major basic ability, however math and physics are related highly in agricultural machine and agricultural civil engineering department, economics and math are in agricultural produce distribution department. Second, the basic ability such as linguistic competence and foreign language ability are essential to complete major subject. Third, if we look into relation of agriculture and life science industry stream specialized subject with major basic competencies, we can find considerable similarity between major field of university and subject name of specialized high school. Fourth, the main opinion is that basic concept and principle, laws of nature are should be main contents which is able to be practical, however experiment and practice is in food processing department, and academic theory is in biotechnology department.

Relationship between Environmental Factors and Macrobenthos Assemblages in Geum Estuary Tidal-flat (금강하구 갯벌 내 환경요인과 저서성무척추동물 군집 분포의 상관관계)

  • Yoo, Jae-Won;Lee, Chae-Lin;Park, Mi-Ra;Yoon, Jihyun;Kang, Sung-Ryong
    • Journal of Wetlands Research
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    • v.21 no.1
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    • pp.84-94
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    • 2019
  • The Seocheon and Yubu Island mudflats in Geum Estuary are important stopover sites for migratory birds as energy supplementation area in the East Asia-Australasian Flyway. Benthic invertebrates in the tidal flats are important food resources for the migratory birds. In other words, benthic invertebrates in the tidal flats play an important ecological role in energy flow. This study was conducted to investigate the relationship between benthic invertebrate assemblages and environmental factors in Seocheon and Yubudo tidal flats in the Geum Estuary. As a result of the benthic invertebrate assemblage during the fall migration season, the total species number was 147, density and biomass were $1,772{\pm}1,342individuals/m^2$ and $445.1{\pm}807.6g/m^2$, respectively. Based on the appearance species and the density data, the result of analysis of mutual similarity among sampling sites was divided into two groups. Group A was the Macrophthalmus-Heteromastus community and Group B was the Spio-Urothoe-Mandibulophoxus community. Group B showed higher mean species number, density and biomass than Group A. The BIO-ENV analysis showed that the benthic invertebrate assemblages were most affected by the combination of sand content % and sediment sorting (${\rho}=0.500$). The variables of significant relationship with species number and biomass were sediment sorting (p=0.015) and the pore water DO(Dissolved Oxygen, p=0.003) in sediment, respectively.

Comparison of Insect Fauna in Transgenic and Common Rice Paddy Fields (형질전환 벼와 일반 벼간 곤충상 비교)

  • Park, Taechul;Choe, Hojeong;Jeong, Hyoujin;Jang, Hojung;Kim, Jukon;Park, Jung-Joon
    • Korean Journal of Environmental Biology
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    • v.36 no.4
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    • pp.488-497
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    • 2018
  • Quantitative classification of insect fauna in transgenic rice in 2 LMO(Living genetically Modified Organism) isolated paddy fields (Gyeongsang National University, Gyeongbuk National University) and rice in 4 paddy fields(Duryang 1, Duryang 2, Hwagye 1, Hwagye 2), were evaluated for consecutive 5 years (2013 to 2017) in Sacheon, Gyeongnam province, and for 2 consecutive years (2015 to 2016) in Gunwi Gyeongbuk province. Sampling insect fauna were evaluated by black light trapping, sticky trapping, visual surveying, and sweeping methods in each target paddy field, respectively. A total of 37,941 individuals, of 464 species from 15 orders, were collected in Sacheon for 5 years. A total of 10,030 individuals, of 366 species from 13 orders, were collected in Gunwi for 2 years. Based on results of comparison between transgenic and non-transgenic paddy fields for 5 consecutive years, the similarity index between LMO paddy field and common paddy field is not different. Thus, this difference is not due to the environment, not the LMO.

Possibility of Intergenerational Exchange in Corporations: A Case Study of Reverse Mentoring on its Purpose and Success Factors (기업 내 세대 교류의 가능성: 국내외 리버스멘토링 (Reverse Mentoring)프로그램 도입 및 성공요소 사례연구)

  • Kim, Ju Hyun;Lee, Ahyoung;Chung, Soondool
    • The Journal of the Korea Contents Association
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    • v.21 no.10
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    • pp.457-475
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    • 2021
  • As Korean society enters an aged society, there is an increasing situation in which various generations coexist in the workplace. This study aimed to analyze corporate reverse mentoring in light of generational exchange. Through the case study methods using literature research and interviews, we categorized the objectives of starting reverse mentoring programs in domestic and foreign companies, and analyzed the possibility of generational exchange with the cases of company A in the US and B in Korea extracted by purposive sampling. Based on social exchange theory, organizational age theory, and generational solidarity theory, the analysis framework presented three propositions: 1) mutual benefit 2) balanced contribution, and 3) sustainability. As a result of the case analyses, there were three main objectives of introducing reverse mentoring: learning IT/social media, promoting corporate diversity, and understanding new trends in the younger generation. In the case of A company in the US and B company in Korea, there was a similarity in mutual benefit and balanced contribution. However, regarding sustainability, there was room for improvement in company B in Korea unlike company A in the US. We expect that reverse mentoring will provide important criteria for success in terms of generational exchange within organizations where various generations coexist in the future.

Comparison of the spatial-temporal distributions of the heterotrophic dinoflagellates Gyrodinium dominans, G. jinhaense, and G. moestrupii in Korean coastal waters

  • Lee, Sung Yeon;Jeong, Hae Jin;Kang, Hee Chang;Ok, Jin Hee;You, Ji Hyun;Park, Sang Ah;Eom, Se Hee
    • ALGAE
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    • v.36 no.1
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    • pp.37-50
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    • 2021
  • Heterotrophic dinoflagellates Gyrodinium spp. are one of the major grazers of phytoplankton in many coastal waters. Gyrodinium dominans, G. jinhaense, and G. moestrupii have similar morphologies but different edible prey species. To explore the variations in the ecological niches of these three species, we investigated their spatial-temporal distributions in Korean waters. Because of the high similarity in morphology among these three Gyrodinium species, we used real-time polymerase chain reactions to quantify their abundance in water samples that were seasonally collected from 28 stations along the Korean Peninsula from April 2015 to October 2018. Cells of G. dominans were found at all sampling stations, G. jinhaense at 26 stations, and G. moestrupii at 22 stations, indicating that all three species were widely distributed in Korea. Furthermore, all three species displayed strong seasonal distributions. The largest numbers of the stations where G. dominans and G. jinhaense cells were present were found during the summer (26 and 23 stations, respectively), but that for G. moestrupii was found in the autumn (15 stations). The abundance of G. dominans was positively correlated with that of G. jinhaense, but not with that of G. moestrupii. The highest abundances of G. dominans (202.5 cells mL-1) and G. jinhaense (20.2 cells mL-1) were much greater than that of G. moestrupii (1.2 cells mL-1). The highest abundances of G. dominans and G. jinhaense were found in July, whereas that of G. moestrupii was found in March. The abundances of G. dominans and G. jinhaense, but not G. moestrupii, were positively correlated with water temperature. Therefore, the spatial-temporal distributions of G. dominans and G. jinhaense were closer than those of G. moestrupii and G. dominans or G. jinhaense. This differs from results based on the relative differences in ribosomal DNA sequences and the types of edible prey reported in the literature. Thus, the variations in spatial-temporal distributions and prey species of these three Gyrodinium species suggest that they may have different ecological niches in Korean coastal waters.