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The Impact on Fish Assemblage by the River Connectivity Fragmentation: Case Study of the Danjang Stream, South Korea (하천 연속성 단절이 어류상에 미치는 영향: 밀양 단장천을 중심으로)

  • Seung-Been Heo;Kang-Hui Kim;Donghyun Hong;Hyeon-Sik Lee;Gu-Yeon Kim;Gea-Jae Joo;Hyunbin Jo
    • Korean Journal of Ecology and Environment
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    • v.55 no.3
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    • pp.231-243
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    • 2022
  • Anthropogenic disturbances on freshwater ecosystem are known to degrade biodiversity, especially on fish assemblage. In this study, we have conducted fish surveys to identify impact of a bridge construction on fish assemblages. A total of eight study sites were surveyed in the Danjang and the Dong Stream in southern part of South Korea from June to November in 2021. The fish samplings were carried out five times, using cast-nets(10×10 mm mesh size), scoop-nets(4×4 mm, 5×5 mm mesh size), set-nets (10×10 mm mesh size), and fish traps (3×3 mm mesh size), along with the Stream/River Ecosystem Survey and Health Assessment by the Ministry of Environment of Korea and basic water quality measurement. Also, we applied the species diversity index and length-weight relationship regressions on certain species to identify interspecific growth rate differences in accordance with study sites. As a result, a total of 782 individuals, 23 species and 10 families were collected. The dominant species was Zacco Koreanus and relative abundance was 50.89%. When applying the length-weight relationship regressions on certain species, the 'b' value for Z. Koreanus was lower at the downstream points than at the upstream points of the construction site. In addition, when comparing to the results of the past survey, relative density of demersal fish at the upstream and downstream points decreased from 26% to 1.4%, and from 18% to 6.3%, respectively. In conclusion, it is considered that bridge construction negatively affects the habitat of fishes, especially on demersal fishes. Therefore, appropriate conservation efforts such as installation of silt protector and sand sedimentation pond are needed to alleviate the disturbance in habitat such as occurrence of turbidity and destruction of micro-habitats.

Estimation of Carbon Stock and Annual CO2 Uptake of Four Species at the Sejong National Arboretum - Pinus densiflora, Metasequoia glyptostroboides, Aesculus turbinata, Chionanthus retusus - (국립세종수목원 교목 4종의 탄소 저장량 및 연간 이산화탄소 흡수량 평가 - 소나무, 메타세쿼이아, 칠엽수, 이팝나무를 대상으로 -)

  • Hak Koo KIm;Yong Sik Hong;Yun Kyung Lim;I Seul Yun;Ki Seok Do;Chan Hyung Jung;Chi Mun Lee;Hoi Eun Roh;Sin Koo Kang;Chan-Beom Kim
    • Journal of Environmental Impact Assessment
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    • v.32 no.1
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    • pp.41-48
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    • 2023
  • This study was conducted to confirm the possibility of a new carbon stock in the Sejong National Arboretum, a major urban greenspace in Sejong-si. This study involved field and ground surveys of 1,336 trees, including 794 Pinus densiflora trees with a diameter at breast height (DBH) of above 5.5cm, which are the most planted in the Sejong National Arboretum, Chionanthus retusus 154 trees planted, Metasequoia glyptostroboides 216 trees, and Aesculus turbinata 172 trees as street trees. Measurements were performed from April to November. Based on the results of the survey, the carbon storage and annual carbon stock were calculated using the annual carbon stock estimation equation used in the forest carbon offset projects. As a result of comparing the carbon stock of the 12cm diameter class, which is the most distributed of four major trees, it was found in the order of C. retusus (0.0136tC/tree), P. densiflora (0.0126tC/tree), M. glyptostroboides (0.0092tC/tree), and A. turbinata (0.0076tC/tree). In addition, the field survey measurement data compared with terrestrial LiDAR measurement data for 20 trees showed a difference of 10.0cm in tree height and 1.7cm in diameter at breast height (p<0.05). In the future, additional carbon stock and annual uptake of other species planted in the arboretum are expected to promote the carbon uptake effect of the arboretum and contribute to the achievement of the national NDC. In the long term, it is also necessary to develop the carbon uptake factor of trees and shrubs mainly used to calculate the exact carbon uptake amount of trees mainly used in urban forests and gardens.

Study of Spatiotemporal Variations and Origin of Nitrogen Content in Gyeongan Stream ( 경안천 내 질소 함량의 시공간적 변화와 기원 연구)

  • Jonghoon Park;Sinyoung Kim;Soomin Seo;Hyun A Lee;Nam C. Woo
    • Economic and Environmental Geology
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    • v.56 no.2
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    • pp.139-153
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    • 2023
  • This study aimed to understand the spatiotemporal variations in nitrogen content in the Gyeongan stream along the main stream and at the discharge points of the sub-basins, and to identify the origin of the nitrogen. Field surveys and laboratory analyses, including chemical compositions and isotope ratios of nitrate and boron, were performed from November 2021 to November 2022. Based on the flow duration curve (FDC) derived for the Gyeongan stream, the dry season (mid-December 2021 to mid-June 2022) and wet season (mid-June to early November 2022) were established. In the dry season, most samples had the highest total nitrogen(T-N) concentrations, specifically in January and February, and the concentrations continued to decrease until May and June. However, after the flood season from July to September, the uppermost subbasin points (Group 1: MS-0, OS-0, GS-0) where T-N concentrations continually decreased were separated from the main stream and lower sub-basin points (Group 2: MS-1~8, OS-1, GS-1) where concentrations increased. Along the main stream, the T-N concentration showed an increasing trend from the upper to the lower reaches. However, it was affected by those of the Osan-cheon and Gonjiamcheon, the tributaries that flow into the main stream, resulting in respective increases or decreases in T-N concentration in the main stream. The nitrate and boron isotope ratios indicated that the nitrogen in all samples originated from manure. Mechanisms for nitrogen inflow from manure-related sources to the stream were suggested, including (1) manure from livestock wastes and rainfall runoff, (2) inflow through the discharge of wastewater treatment plants, and (3) inflow through the groundwater discharge (baseflow) of accumulated nitrogen during agricultural activities. Ultimately, water quality management of the Gyeongan stream basin requires pollution source management at the sub-basin level, including its tributaries, from a regional context. To manage the pollution load effectively, it is necessary to separate the hydrological components of the stream discharge and establish a monitoring system to track the flow and water quality of each component.

A Research on the Special Characteristics of the Changes of the Vegetations in the World Cup Park Landfill Slope District (월드컵공원 사면지구 식생현황 및 변화 특성 연구)

  • Han, Bong-Ho;Park, Seok-Cheol;Choi, Han-Byeol
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.4
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    • pp.1-15
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    • 2023
  • This research intended to reveal the special characteristics of the vegetation structure and the tendency of change of -landfill slope districts, which are reclaimed land, through an investigationsinto the presently existent vegetation and plant community structure of the World Cup Park landfill slope district. For the analysis of changes in vegetation, this study compared the results of field surveys in 1999, 2003, 2005, 2007, 2008, 2012, 2016, and 2021. For the investigation into the plant community structure, a field investigation was carried out in 2021 with six fixed investigation districts designated in 1999 as subjects. To analyze the change in the plant community structure, the past data on the population, the number of the species, and the species diversity by the layer in 2021 were compared and analyzed in the landfill slope district, which is reclaimed land. The changes of the vegetation distribution and the power had been affected by typhoons (Kompasu). Above the plantation foundation, which had been dry and poor, Salix koreensis, marsh woody plants that had formed the community, decreased greatly. The Robinia pseudoacacia community, after the typhoon in 2010, decreased in the number of species and population. Afterward, it showed a tendency to rebound. Regarding the Ailanthus altissima-Robinia pseudoacacia-Paulownia tomentosa community, the number of the species and the population had shown a change similar to the Robinia pseudoacacia community. The Paulownia tomentosa and the Ailanthus altissima have been culled. The slope was predicted as a Future Robinia pseudoacacia forest. The Salix pseudolasiogyne community has been transitioning to a Robinia pseudoacacia forest. Only some enumeration districts, the Robinia pseudoacacia forests and the Salix pseudolasiogyne, had been growing. However, most had been in been declining. It was predicted that this community will be maintained as a Robinia pseudoacacia forest in the future. As these vegetation communities are the representative vegetation of the landfill slope districts, which is reclaimed land, there is a need to understand the ecosystem changes of the community through continuous monitoring. The results of this research can be utilized as a basic material for the vegetation restoration of reclaimed land.

Improving the nutrition quotient and dietary self-efficacy through personalized goal setting and smartphone-based nutrition counseling among adults in their 20s and 30s (개인별 목표 설정과 스마트폰 기반 영양상담을 통한 20-30대 성인의 영양지수 및 식이 자아효능감 향상)

  • Dahyeon Kim;Dawon Park;Young-Hee Han;Taisun Hyun
    • Journal of Nutrition and Health
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    • v.56 no.4
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    • pp.419-438
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    • 2023
  • Purpose: This study examines the effectiveness of personalized goal setting and smartphone-based nutrition counseling among adults in their 20s and 30s. Methods: Nutrition counseling was conducted for a total of 30 adults through a 1:1 chat room of a mobile instant messenger, once a week for 8 weeks. The first week of counseling included a preliminary online questionnaire survey and a dietary intake survey. Based on the results of the preliminary survey, 2 dietary goals were set in the second week and the participants were asked to record their achievements on a daily checklist. From the third week onwards, counselors sent feedback messages based on the checklist and provided information on dietary guidelines in a card news format every week. Post-counseling questionnaires and dietary intake surveys were conducted in the seventh week. Changes in dietary habits during the counseling were reviewed in the eighth week, followed by a questionnaire survey on the evaluation of the counseling process. Results: The nutrition quotient (NQ) scores and self-efficacy scores were significantly higher after nutrition counseling. The NQ scores of consumption frequencies of fruits, milk and dairy products, nuts, fast food, Ramyeon, sweet and greasy baked products, sugarsweetened beverages, the number of vegetable dishes at meals, and breakfast frequency were significantly higher after nutrition counseling. The intake of protein, vitamin A, thiamin, riboflavin, folate, calcium, and iron, and the index of nutritional quality of vitamin A, riboflavin, folate, calcium, and iron were higher after nutrition education. The participants were satisfied with the nutrition counseling program and the provided nutrition information. Conclusion: Personalized goal setting and smartphone-based nutrition counseling were found to be effective in improving the quality of diet and self-efficacy in young adults. Similar results were obtained in both the underweight/normal weight and the overweight/obese groups.

A Study on the Status and Editors' Perceptions of the Data Sharing Policies of International Journals Published in Korea (한국의 국제 학술지 데이터 공유 정책 현황 및 편집인 인식에 관한 연구)

  • Seo Young Bai;Jihyun Kim
    • Journal of the Korean Society for information Management
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    • v.40 no.3
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    • pp.25-54
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    • 2023
  • At a time when open data receives attention as an international trend, there is a need to discuss the role of international journals in Korea to support data sharing. Based on surveys and interviews of editors from the international journals, we identified factors affecting the policy adoption and examined the journal editors' perception on the adoption and components of the data sharing policy. As a result, scholarly journals that have adopted or are planning to adopt policies have recognized that data sharing is an international trend and can contribute to research development, but they stressed that efforts to improve the perception of data sharing were still necessary. Educational activities and compensation for sharing data were needed at scholarly journals' and communities' level. Also, components perceived important and selected by more than half of the editors as mandatory were 'data availability statement', 'data sharing level', 'data sharing method', and 'data citation'. While scholarly journals do not always need to mandate data sharing, it was necessary to mention conditions where data cannot be shared through data availability statements. The role of the organization developing and operating a repository appropriate for situations in Korea was also emphasized. In addition, by identifying factors affecting the policy adoption, significant differences were found in Journal Impact Factor quartiles, publication type, and subject area. This finding indicated that journals with a high impact factor are likely to have resources to support data sharing, and open access or hybrid journals are likely to have interest in open data as a part of open science. In the medical research area, active movements for data sharing in academic communities have promoted the adoption of data sharing policies. This study would be used as basic data to facilitate the adopton and operation of scholarly journals' data sharing policies in Korea.

Viral Load Dynamics After Symptomatic COVID-19 in Children With Underlying Malignancies During the Omicron Wave

  • Ye Ji Kim;Hyun Mi Kang;In Young Yoo;Jae Won Yoo;Seong Koo Kim;Jae Wook Lee;Dong Gun Lee;Nack-Gyun Chung;Yeon-Joon Park;Dae Chul Jeong;Bin Cho
    • Pediatric Infection and Vaccine
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    • v.30 no.2
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    • pp.73-83
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    • 2023
  • Purpose: This study aimed to investigate the viral load dynamics in children with underlying malignancies diagnosed with symptomatic coronavirus disease 2019 (COVID-19). Methods: This was a retrospective longitudinal cohort study of patients <19 years old with underlying hemato-oncologic malignancies that were diagnosed with their first symptomatic severe acute respiratory syndrome coronavirus 2 polymerase chain reaction (PCR)-confirmed COVID-19 infection during March 1 to August 30, 2022. Review of electronic medical records and telephone surveys were undertaken to assess the clinical presentations and transmission route of the patients. Thresholds of negligible likelihood of infectious virus was defined as E gene reverse transcription (RT)-PCR cycle threshold (Ct) value ≥25. Results: During the 6-month study period, a total of 43 children with 44 episodes of COVID-19 were included. Of the 44 episodes, the median age of the patients included was 8 years old (interquartile range [IQR], 4.9-10.5), and the most common underlying disease was acute lymphoid leukemia (n=30, 68.2%), followed by patients post-hematopoietic stem cell transplantation (n=8, 18.2%). Majority of the patients had mild COVID-19 (n=32, 72.7%), and three patients (7.0%) had severe/critical COVID-19. Furthermore, 2.3% (n=1) died of COVID-19 associated acute respiratory distress syndrome. The largest percentage of the patients showed E gene RT-PCR Ct value ≥25 between 15-21 days (n=13, 39.4%), followed by 22-28 days (n=10, 30.3%). In 15.2% (n=5), E gene RT-PCR Ct value remained <25 beyond 28 days after initial positive PCR. Refractory malignancy status (β, 67.0; 95% confidence interval, 7.0-17.0; P=0.030) was significantly associated with prolonged duration of E gene RT-PCR <25. A patient with prolonged duration of E gene RT-PCR Ct value <25 was suspected to have infectivity shown by the transmission of the virus to his mother at day 86 after his initial positive test. Conclusions: Children that acquire symptomatic COVID-19 during refractory malignancy state are at a high risk for prolonged shedding warranting PCR-based transmission precautions in this cohort of patients.

The Flora of Vascular Plants in Bonghwasan Mountain (Namwon) of Baekdudaegan, Korea (백두대간 봉화산(남원시)의 관속식물상)

  • Ju Eun Jang;Hyeon Jin Jeong;Young-Soo Kim;Ji Eun Kim;Jung Sim Lee;Aleksey Kim;Beom Kyun Park;Su-Young Jung;Hee-Young Gil
    • Korean Journal of Environment and Ecology
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    • v.37 no.4
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    • pp.235-250
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    • 2023
  • This study was carried out to identify the vascular flora of Mt. Bonghwa in the Baekdudaegan Mountain range, located on the border between Namwon City and Jangsu Country in Jeollabuk Province and Hamyang Country in Gyeongsangnam Province and use them as basic data for the conservation of plant diversity and prevention of the spread of alien plants. Specimens deposited at the Herbarium of Korea National Arboretum (KH) were reexamined, and 15 field surveys were conducted from April 2020 to July 2023. The result revealed a total of 466 taxa, consisting of 97 families, 279 genera, 409 species, 16 subspecies, 32 varieties and 9 forms, Of which, eight taxa were endemic plants, and one taxon, Aconitum coreanum (H.Lév.), belonged to the vulnerable (VU) on the national red list species. Moreover, there were 57 floristic target species, including 1 taxon of grade V, 9 taxa of grade III, 14 taxa of grade II, and 33 taxa of grade I, whereas there were 24 taxa of alien plants and 1 taxon of ecosystem disturbance species. In the usefulness survey, 353 taxa were for food, 3 for textiles, 71 for medicinal use, 21 for ornamental use, 108 for pasture use, 2 for industrial use, 7 for miscellaneous use, and 11 for timber plants.

Species Composition and Vegetation Structure of Abies koreana Forest in Mt. Jiri (지리산 구상나무림의 종조성 및 식생구조)

  • Jin-Soo Lee;Dong-Bin Shin;A-Rim Lee;Seung-Jae Lee;Jun-Soo Kim;Jun-Gi Byeon;Seung-Hwan Oh
    • Korean Journal of Environment and Ecology
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    • v.37 no.4
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    • pp.259-272
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    • 2023
  • This study set up 49 survey areas with an area of about 400 square meters in Abies koreana natural habitat to identify the species composition and vegetation structure of the A. koreana forest in the Mt. Jiri Nation Park, conducted field surveys using phytosociological methods, and performed the cluster analysis using the Two-Way Indicator Species Analysis (TWINSPAN) and Table manipulation. Subsequently, species composition analysis using the importance value, species diversity analysis, DBH analysis, sapling analysis, and similarity analysis was conducted by each cluster type. The cluster analysis classified the A. koreana forest in Mt. Jiri into five clusters, A, B, C, D, and E. The forest was divided into two clusters, Magnolia sieboldii-Dryopteris crassirhizoma-Sasa borealis and Betula ermanii-Solidago virgaurea-Calamagrostis arundinacea. The former was classified as type A and B by Cornus controversa-Hydrangea macrophylla, and the latter was classified as type E, a typical community, and a Sorbus commixta-Rhododendron mucronulatum cluster. And the S. commixta-R. mucronulatum cluster was divided into C type and D type by Picea jezoensis-Ligularia fischeri and Ainsliaea acerifolia. Through vegetation analysis, the importance value of A. koreana, Quercus mongolica, Acer pseudosieboldianum, Fraxinus sieboldiana, and B. ermanii was highly expressed in the A. koreana forest in Mt. Jiri. Regarding species diversity, the results were similar to those reported in other studies of A. koreana forests in Mt. Jiri. The analysis of diameter at breast height (DBH) showed that A. koreana dominated all layers, and the growth of saplings was also good, indicating that the dominance of A. koreana is expected to continue for a while. However, when considering the value of biodiversity that is expected to increase and threats caused by climate change, systematic preservation and management are required to respond to various threats based on continuous monitoring.

Changes in Perceptions of Science Classes Using Artificial Intelligence among Elementary Teachers Participating in Research School (연구학교 참여 초등교사의 인공지능 활용 과학 수업에 관한 인식 변화)

  • Kim, Tae Ha;Yoon, Hye-Gyoung
    • Journal of Korean Elementary Science Education
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    • v.42 no.3
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    • pp.467-479
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    • 2023
  • For the successful implementation of education using artificial intelligence (AI) in schools, the perception of teachers is important. This study focuses on elementary school teachers and their perception of the need and teaching efficacy of science classes using AI before and after participating in a research school program. The analysis explores four key aspects, namely, learning, teaching, assessment, and communication. The study recruited 24 elementary school teachers from a school designated by the Gangwon Provincial Office of Education to participate in a year-long research school program. The study collected data using pre- and post-program surveys to explore changes in the perception of teachers regarding AI-based science classes. Furthermore, the researchers conducted individual in-depth interviews with four elementary school teachers to investigate the experience factors that influenced the changes in their perception of the aforementioned classes. The main findings were as follows. First, elementary school teachers were positively aware of the need for science classes using AI even prior to their research school experience; this perception remained positive after the research school program. Second, the science teaching efficacy of the elementary school teachers using AI was generally moderate. Even after the research school experience, the study found no statistically significant increase in efficacy in teaching science using AI. Third, by analyzing the necessity-efficacy as quadrants, the study observed that approximately half of the teachers who participated in the research school reported positive changes in learning, teaching, and assessment. Fourth, the study extracted four important experience factors that influenced the perception of the teachers of science classes using AI, namely, personal background and characteristics, personal class practice experience, teacher community activities, and administration and work of school. Furthermore, the study discussed the implications of these results in terms of the operation of research schools and science education using AI in elementary schools.