• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.616-624
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• 2020

International trade is one of the primary ways that non-native species spread worldwide. Korea and China are geographically close and have a large mutual trade volume. To investigate the population movement of the invasive whitefly(Bemisia tabaci Gennadius) between the two countries, we compared the biotype distribution, insecticidal response, and the TYLCV(tomato yellow leaf curl virus) viruliferous rate of local populations collected in 2019. Based on the mitochondrial DNA COI sequences of B. tabaci, only the Q biotype was found in all populations in Korea, whereas the B biotype (14.3%) and Q biotype (85.7%) were found in China. In the haplotype composition of the B. tabaci Q biotype, only the Q1 group[Q1H1(79.8%) and Q1H2(20.2%)] was observed in China, but the Q1 group [Q1H1(1.7%) and Q1H2(97.5%)] and the Q2 group(only one individual) were found in Korea. The Korean populations showed high mortality(more than 80%) from 15 commercial insecticides, but the Chinese populations showed significantly low mortality from eight insecticides. No TYLCV infections were observed in the Korean populations while the average TYLCV viruliferous rate was 21.4% in the Chinese populations. Taken together, the results suggest that the population structures of B. tabaci in the two countries are different and may have different immigration histories.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.528-553
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• 2020

Upland fields are characterized by dry environments, a high degree of disturbance by farming practices such as double-cropping, and a high diversity of crops compared to other field types. This study focused on the floristic composition and characteristics of upland fields in South Korea. Flora surveys were conducted in 36 areas in nine provinces at two times (June and August) in 2015. The results showed that the vascular plants in the upland fields in South Korea included 532 taxa, containing 100 families, 322 genera, 483 species, nine subspecies, 37 varieties, one form, and two hybrids. Among the 100 families, Asteraceae was the most diverse in species (75 taxa), followed by Poaceae (68 taxa), Fabaceae (34 taxa), Polygonaceae (21 taxa), Rosaceae (19 taxa), and Liliaceae (17 taxa). Based on the occurrence frequency of each species, Acalypha australis L. (100%), and Artemisia indica Willd. (100%) were the highest, followed by Humulus scandens (Lour.) Merr., Rorippa palustris (L.) Besser, Conyza canadensis (L.) Cronquist, Erigeron annuus (L.) Pers., Lactuca indica L., Commelina communis L., Digitaria ciliaris (Retz.) Koeler, Echinochloa crus-galli(L.) P.Beauv., Cyperus microiria Steud., and Oxalis corniculata L. The biological type of upland fields in South Korea was determined to be Th-R₅-D₄-e type. Rare plants were found in 11 taxa: Taxus cuspidata Siebold & Zucc, Magnolia kobus DC, Clematis trichotoma Nakai, Aristolochina contorta Bunge, Buxus sinica (Rehder & E.H.Wilson) M.Cheng var. koreana (Nakai ex Rehder) Q.L.Wang, Melothria japonica (Thunb.) Maxim, Mitrasacme indica Wight, Lithospermum arvense L., Carpesium rosulatum Miq., Allium senescens L., and Pseudoraphis sordida (Thwaites) S.M.Phillips & S.L.Chen. Ninety-seven taxa contained naturalized plants composed of 24 families, 68 genera, 97 species, one variety, and one form. The urbanization and naturalization indices were 30.5% and 18.4%, respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.2
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• pp.96-101
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• 2021

This study was conducted to determine the effect of horse manure compost application on Italian ryegrass (IRG) yield and volcanic ash soil characteristics. Because the number of horses in Korea is growing, the amount of horse manure is growing. Jeju island, where about 55 % of the horses live, is composed of volcanic ash soil. This study was conducted for about 7 months. Sowing was conducted on October 2019. Harvesting was conducted at heading stage(2020.5.). Five treatments were established based on the horse manure compost composition. These were 100 % chemical fertilizer (CF), the combination of 50 % horse manure and 50 % chemical fertilizer (combination), horse manure with 50 % nitrogen (HM 50 %), horse manure with 100 % nitrogen (HM 100 %), and horse manure with 150 % nitrogen (HM 150 %). The plant height and dry matter yield were investigated to determine the forage yield and the soil characteristics of pH, total nitrogen, available phosphate, and organic matter were analyzed. The plant heights in the CF, combination, and HM 150 % treatments were 147.8 cm, 144.3 cm, and 147.1 cm respectively (Table 2). Dry matter yield in the CF treatment was about 23,807 kg/ha, which tended to be the highest dry matter yield. HM 150 % and the combination treatment were about 18,804 and 18,455 kg/ha, respectively, which tended to be the highest dry matter yield of the treatments amended with horse manure compost. The dry matter yield of the HM 100 % and HM 50 % treatments was about 15,801 kg/ha and 14,446 kg/ha, respectively (Table 2). The pH of the surface soil tended to increase after the experiment. The soil pH of the HM 150 % treatment was significantly higher than the soil pH of the other treatments. The pH was affected by the amount of horse manure compost, with a pH of 8.1. The available phosphate in the treatments in which horse manure compost was added was higher than the available phosphate in the CF treatment. And the available phosphate in the HM 150 % treatment was significantly higher than the available phosphate in the other treatments (p < 0.05)(Table 3). These results suggest that 50 % horse manure should be applied to IRG as the basal fertilizer and the remaining 50 % should be chemical fertilizer as the top fertilizer. This can provide the proper IRG dry matter yield with less effect on volcanic ash soil.

• Journal of The Korean Association For Science Education
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• v.41 no.2
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• pp.145-154
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• 2021

This study aims to investigate teachers' perceptions of the composition of high school science elective courses ahead of the 2022 curriculum revision, and to derive implications for the organization of the 2022 revised science curriculum in preparation for the full implementation of the high school credit system. To this end, a survey was conducted by randomly sampling high schools across the country. A total of 192 science teachers responded to the questionnaire. In addition, 12 high school science teachers were selected as a focus group, and in-depth interviews were conducted to investigate opinions on the restructuring of elective courses in science. Main research results include 129 (67.2%) science teachers in the survey answered that the current 2015 curriculum's science and elective courses system should be maintained. In the next curriculum, when reconstructing science elective subjects, it is necessary to provide an opportunity to experience the entire contents of each science field through Science I·II system as before, and to ensure student choice in preparation for the credit system. In addition, the opinion that general elective subjects should be organized to include all the contents of science I and II subjects was the highest. Through in-depth interviews, science teachers emphasized that the current science I subject system allows access to the content areas of science as much as possible as the number of subjects is small, and that subjects, such as physics, where the hierarchy of concepts is important, should deal with important content within one subject rather than divided by area. On the other hand, in the current I subject system, there is no subject for liberal arts students to choose from, so teachers suggested that science electives should be organized by subdividing each content area. Based on the research results, the necessity of organizing high school science elective courses in consideration of the purpose of the high school credit system, ways to organize science-convergence elective courses as subjects for all students regardless of career aptitude, ways to organize science-career elective courses, and ways to organize science elective courses in connection with the college admission system were proposed.

• Journal of Life Science
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• v.31 no.5
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• pp.475-480
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• 2021

Interest in edible insects such as Protaetia brevitarsis has increased rapidly, and several insect producers use these insects in industrialized mass production. However, mass rearing of insects can cause insect diseases. Sprouted barley is a valuable source of nutrients and has antioxidant, antimicrobial, anti-inflammatory, and anti-cancer effects. This study was conducted to investigate the effect of sprouted barley as a feed additive for producing healthy P. brevitarsis larvae. P. brevitarsis larvae were fed feeds with or without sprouted barley, and their body weight and larval period wewe checked weekly. To confirm the antibacterial effects of sprouted barley, in vitro bioassays were performed by counting Serratia marcescens colonies, and in vivo bioassays were performed by determining the survival rate and body weights of the S. marcescens-infected larvae. Larvae fed different feeds were analyzed for their nutrient compositions (i.e., such as proximate composition, minerals, amino acids, and heavy metals). Larvae fed 5% and 10% sprouted barley had maximum weight increases of 19.2% and 23.1%, respectively. Both treatment groups had significantly shorter larval periods than those of the control group. Sprouted barley markedly inhibited the growth of entomopathogenic S. marcescens. Furthermore, larvae fed sprouted barley exhibited higher Cu, Zn, and K levels. Seventeen amino acids were present in larvae fed sprouted barley, of which, tyrosine and glutamic acid were predominant. No heavy metals were detected in any of the investigated groups. Therefore, sprouted barley may be a suitable feed additive for producing high-quality P. brevitarsis larvae.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.2
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• pp.12-28
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• 2021

Based on the global smart city promotion trend, in 2018, the "Fourth Industrial Revolution Committee" selected "sustainability" and "people-centered" as keywords in relation to the direction of domestic smart city policy. Accordingly, the Living Lab program, which is an active citizen-centered innovation methodology, is applied to each stage of the domestic smart city construction project. Through the Living Lab program, and in collaboration with the public and experts, the smart city discovers local issues as it focuses on citizens, devises solutions to sustainable urban problems, and formulates a regional development plan that reflects the needs of citizens. However, compared to citizen participation in urban regeneration projects that have been operated for a relatively long time, participation in smart city projects was found to significantly differ in level and sustainability. Therefore, this study conducted a comparative analysis of the characteristics of citizen participation at each stage of an urban regeneration project and, based on Arnstein's "Participation Ladder" model, examined the level of citizen participation activities in the Living Lab program carried out in a smart city commercial area from 2018 to 2019. The results indicated that citizen participation activities in the Living Lab conducted in the smart city project had a great influence on selecting smart city services, which fit the needs of local residents, and on determining the technological level of services appropriate to the region based on a relatively high level of authority, such as selection of smart city services or composition of solutions. However, most of the citizen participation activities were halted after the project's completion due to the one-off recruitment of citizen participation groups for the smart city construction project only. On the other hand, citizens' participation activities in the field of urban regeneration were focused on local communities, and continuous operation and management measures were being drawn from the project planning stage to the operation stage after the project was completed. This study presented a plan to revitalize citizen participation for the realization of a more sustainable smart city through a comparison of the characteristics and an examination of the level of citizen participation in such urban regeneration and smart city projects.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.658-666
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• 2020

The purpose of this study was to select a suitable planting substrate for multilayered plantings in an apartment landscape space. The experiment was conducted between May to October 2019, at the National Institute of Horticultural and Herbal Science. Planting substrate was prepared in six repetitions of eight treatment zones using mulching material, horticultural soil, bottom ash, and subgrade soil. Rosa hybrid 'Barkarole' and Hydrangea macrophylla 'Nikko Blue' were selected as the experimental plants. We investigated the monthly variation and effect of the substrate type on the growth (plant height, number of branches, leaf length, leaf width, and plant area of the substrates) of the plants. In R. hybrid 'Barkarole' grown in 20 cm of horticultural soil and 10 cm of bottom ash, the plants were taller(102.2±5.8 cm), had more branches (5.5±0.6 each), longer leaves (10.9±1.0 cm), and greater leaf width (6.2±0.5 cm) and plant area (4077.1±416.6 cm²)(p<0.05). H. macrophylla 'Nikko Blue' showed the best growth from 3cm of mulching, 20cm of horticultural topsoil, and 10cm of bottom ash, which resulted in taller plants (43.6±2.1 cm), more branches (4.9±0.8 each), longer leaves (7.2±0.5 cm), and greater leaf width(4.3±0.3 cm) and plant area (344.5±43.2 cm²). Through this study, it was possible to propose an optimal planting substrate for shrubs for multi-layered landscaping.

• Korean Journal of Heritage: History & Science
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• v.53 no.4
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• pp.100-117
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• 2020

National Treasure no. 101, the stupa of State Preceptor Jigwang from the Beopcheonsa Temple Site in Wonju has been transferred from place to place and reassembled several times since it was built. In particular, overall dismantling and repair was carried out in 1957 to restore parts damaged by bombing during the Korean War. Documented information on the repair process and materials used at that time does not exist. However, various types of metal materials used for this stupa have been identified during conservation work. Besides clamps anchor bolts, 9mm-thick circular rebars were mainly used for joining the parts of this stupa, while circular rebars and wires of various thicknesses were used for joining the parts with mortar restoration materials. Although deformed bars are typically used for stone pagodas classified as architectural structures, smooth circular rebars were used in this case. In terms of restoration using mortar, material shapes were transformed, bound alternately, and twisted irregularly to improve bonding strength and coherence in order to insert restoration materials and to bolster structural weaknesses. In addition, metallographic analysis showed the material to be hypo-eutectoid steel with low carbon content. Many non-metallic inclusions in the shape of drops of different sizes were included, which do not affect the whole elemental composition due to the very small quantities involved. Qualitative and EPMA analysis of Mn and S, which were not identified by SEM-EDS area analysis, established an even distribution of MnS in crystal grains of the microstructure, regardless of the shape of the samples. It is presumed that secondary homogenization and softening might have been conducted after manufacturing to facilitate the working process. Furthermore, in consideration of properties indicating that the thinner the steel is, the less carbon content contained and the greater the elasticity and elongation, it is judged that restoration work was ordered.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.1
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• pp.62-70
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• 2021

The purpose of this study was to determine the optimal digestible energy levels on pregnancy mares. Physical changes and fecal microorganism in pregnant horse and changes in birth characteristics of neonatal foals were investigated. The experiment was conducted by 18 mares (Jeju corssed bred, older than 36 months) into three treatment groups. The experimental diet consisted of 80%, 100%, 120% digestible energy levels based on NRC. The average daily intake was lower in the 120% (8.75±1.01) than the 100% (9.34±0.92), 80% (9.14±0.88) and there was significant difference (p<0.05). The feed efficiency was lower in the 120% than 80%, 100% (p<0.05). Total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride was higher in 120% than others (p<0.05). However there were no health problem and there was no difference between the treatment groups in the birth characteristics of neonatal foals. At the phylum level, Fibrobactres was difference by digestible energy levels, 80% (8.53%) was higher than 100%, 120%. At the genus level, Bacteroides and Kineothrix increased in fecal proportions with increasing digestible energy levels (p<0.05). Fibrobacter showed higher composition at 80% than 100% and 120% (p<0.05).

• Journal of The Korean Association For Science Education
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• v.40 no.6
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• pp.657-670
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• 2020

The knowledge-information-processing competency is the most essential competency in a knowledge-information-based society and is the most fundamental competency in the new problem-solving ability. Data-driven science inquiry, which emphasizes how to find and solve problems using vast amounts of data and information, is a way to cultivate the problem-solving ability in a knowledge-information-based society. Therefore, this study aims to develop a teaching-learning model and strategy for data-driven science inquiry and to verify the validity of the model in terms of knowledge information processing competency. This study is developmental research. Based on literature, the initial model and strategy were developed, and the final model and teaching strategy were completed by securing external validity through on-site application and internal validity through expert advice. The development principle of the inquiry model is the literature study on science inquiry, data science, and a statistical problem-solving model based on resource-based learning theory, which is known to be effective for the knowledge-information-processing competency and critical thinking. This model is titled "Exploratory Scientific Data Analysis" The model consisted of selecting tools, collecting and analyzing data, finding problems and exploring problems. The teaching strategy is composed of seven principles necessary for each stage of the model, and is divided into instructional strategies and guidelines for environment composition. The development of the ESDA inquiry model and teaching strategy is not easy to generalize to the whole school level because the sample was not large, and research was qualitative. While this study has a limitation that a quantitative study over large number of students could not be carried out, it has significance that practical model and strategy was developed by approaching the knowledge-information-processing competency with respect of science inquiry.