• Journal of Photoscience
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• v.7 no.2
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• pp.39-44
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• 2000

To examine the chilling tolerance lipids, we compared the chilling susceptibility of photosystem II of wild type tobacco plants with that of transgenic tobacco plants, in which the sensitivity to chilling had been enhanced by genetic modification of fatty acid unsaturation of chloroplast membrane lipids. The transgenic tobacco plants were found to contain reduced levels of unsaturated membrane fatty acids by being tansformed with cDNA for glycerol-3-phosphate acyltransferase from squash. For the purpose of studying on the functional integrity of photosystem II during low-temperature photoinhibition, the photochemical efficiency was measured as the ration of the maximun fluorescence of chlorophyll (Fv/Fm) of photosystem II. In parallel with an investigation on the transgenic plants, susceptibility of chilling-resistant species, such as spinah and pea, and of chilling-sensitive ones, such as squash and sweet potato, to low-temperature photoinhibition was also compared in terms of room temperature-induced chlorophyll fluorescence from photosystem II. When leaf disks from the two genotypes of tobacco plants were exposed to light at 5$^{\circ}C$, the transgenic plants showed more rapid decline in photochemical activity of photosysytme II than wild-type plants. When they were pretreated with lincomycin, an inhibitor of chloroplast-encoded protein synthesis, the extent of photoinhibition was even more accelerated. More impottantly, they showed a comparable extent of photoinhibition in the presence of lincomycin, making a clear contrast to the discrepancy observed in the discrepancy observed in the absence of lincomycin. Restoration of Fv/Fm during recovery from low-temperature photoinhibition occurred more slowly in the transgenic tobacco plants than the wild-type. These findings are discussed in relation to fatty acid unsaturation of membrane phosphatidylglycerol. It appears that the ability of plants to rapidly regenerate the active photosystem II complex from might explain, in part, why chilling-resistant plants can toleratlow-temperature photoinhibition.

• Journal of Photoscience
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• v.5 no.1
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• pp.1-10
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• 1998

The susceptibility of chilling-resistant spinach plants. and of chilling-sensitive squash plants to photoinhibition was compared in terms of the activity of photosystem II, in relation to the deuce of fatty acid unsaturation of chloroplast membrane lipids. From thylakoid membranes of the plants. monogalactosyl diacylgtycerol, digalactosyl diacylglycerol. sulfoquinovosyt diacylglycerol, and phosphatidylglycerol were seperated as major lipid classes. It was found that the content of cis-unsaturated fatty acids of phosphatidylglycerol was greater by 32% in spinach than that in squash. When leaf disks were exposed to light at 5$\circ$C, 15$\circ$C and 25$\circ$C, photochemical efficiency of photosystem II. measured as the ratio of the variable to the maximum fluorescence of chlorophyll, declined markedly in squash plants, as compared to spinach plants. When leaf disks were exposed to strong light in the presence of lincomycin, an inhibitor of protein synthesis in chloroplasts, photoinhibition was accelerated in the two types of plants. Moreover, lincomycin treatment abolished the differences in the degree of susceptibility to strong light, which had been observed between the two types of plants. When the extent of photoinhibition of photosystem II-mediated electron transport was compared in thylakoid membranes isolated from the two types of plants, there were no differences in the degree of inactivation of photosystem II activity. However, when intact leaf disks were exposed to strong light either at 10$\circ$C or at 25$\circ$C, and then were allowed to recover either at 17$\circ$C or at 25$\circ$C in dim light. chilling-resistant plants such as spinach and pea showed marked recovery from photoinhibition, in contrast to chilling-sensitive plants, such as squash and sweet potato. whose recovery was strongly dependent on the temperature. These findings are discussed in relation to the unsaturation of fatty acids in membrane phosphatidylglycerol. It appears that fatty acid unsaturation of membrane lipids accelerates the recovery of photosystem H from photoinhibition, without affecting the photo-induced inactivation process of photosystem II associated with photoinhibition.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.1
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• pp.15-36
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• 2020

The purpose of this study is to provide basic data for the establishment of the management plan of Seoullo 7017 after analyzing the characteristics of immigration plants in addition to those introduced plants. The taxa number of plants appeared as 276 taxa including 82 families, 161 genera, 246 species, 1 subspecies, 22 varieties and 7 forms. Among them, immigration plants appeared 79 classification groups, including 32 families, 65 genera, 77 species and 2 varieties. Invasive alien plants appeared as 22 classification groups in 79 classification groups of immigration plants. The ratio of America origin plants, second period(1932~1960) in introduction time and the wide diffusion species is high. In June, the growth and occurrence time of the immigration plants was the highest by monthly the characteristics of the growth of the immigration plants, the immigration plants appeared mostly. In case of dormancy form among life-form, the therophytes(th), in the propagation form-radicoid form, the R₅(monophyte), in the propagation form-disseminule form, the gravity D₄(having no special modification for dissemination), and in the growth form, the erect form(e) was high. The various immigration plants appeared in green areas covered by Zoysia japonica and low Hedera helix densities. This study is the first flora study since Seoullo 7017 was opened in 2017. And so continuous flora monitoring is required for Seoullo 7017.

• The Korea Journal of Herbology
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• v.24 no.2
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• pp.57-65
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• 2009

Objectives : This study was aimed to developing Korean herbalogy of the plants belonging to Aspidiaceae in Korea. Methods : The herbological books and papers published at home and abroad were researched. The total list of Aspidiaceae was made and Medicinal plants in Aspidiaceae was classified. The medicinal properties, action and applications of medicinal plants were investigated. Results : 1. There are totaled to 17 genera and 130 species in Aspidiaceae in Korea and among them medicinal plants are 11 genera, 31 species, some 24% in total. 2. Athyrium genus is main kind enough that it has 32 species among 130 species in Aspidiaceae, and medicinal plants of Dryopteris is 4 species. 3. The rhizome is the main medicinal parts if medicinal plants in the Aspidiaceae, which is used in 24 species. 4. According to nature and flavor of medicinal plants in the Aspidiaceae, they were classified into cool 15 and cold 8 species ; bitter taste 19, and little bitter taste 15 in the order. 5. According to meridian propism of medicinal plants in the Aspidiaceae, they were classified into liver meridian 5 species, stomach meridian 3 species. 6. According to the properties and principal curative action, they were classified into drugs for clearing away heat 25 species, drugs for detoxification 22 species, drugs for promoting diuresis 16 species in the order. 7. The number of toxic species in the Aspidiaceae was examined to be 5 species. Conclusions : There are totaled to 17 genera and 130 species in Aspidiaceae in Korea and among them medicinal plants are 11 genera, 31 species, some 24% in total. They were classified into drugs for clearing away heat, drugs for detoxification, drugs for promoting diuresisr.

• Korean Journal of Ecology and Environment
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• v.54 no.4
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• pp.327-333
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• 2021

The two main hypotheses that explain why invasive alien plants successfully colonize new environments are: 1) invasive alien plants are functionally different from native plants in a community, and 2) the plants can adapt well to new environments because they are functionally similar to native plants. The present study investigated the functional traits of naturalized alien herbaceous plants and their native neighbors in a riparian park area near the Hapcheon-Changyeong weir along the Nakdong River to determine which of the two hypotheses applied to the study area. According to the results, leaf functional traits, such as leaf area, specific leaf area, leaf thickness, leaf dry matter content, leaf nitrogen content, and leaf carbon content differed between naturalized alien and native plants, which could be attributed to the higher leaf nitrogen contents in naturalized alien plants than in native plants. The high leaf nitrogen contents are associated with high photosynthetic rates, which lead to effective resource use and rapid growth; therefore, naturalized alien plants growing in the study area were considered to have such functional traits. The results of the present study support the hypothesis that the successful establishment of invasive alien plants is attributed to the functional trait differences between invasive and native plants.

• Journal of The Korean Association For Science Education
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• v.17 no.3
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• pp.261-271
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• 1997

This study evaluates on students' understanding and misunderstanding of homeostasis, classification of animals and plants, and food production in plants, and analyzes the teacher factor as a possible source of students' misconception. A total number of 863 students and 47 biology teachers at the middle and high school were randomly selected. Students' conceptions and misconceptions were measured with concept evaluation statements (CES) which was translated into Korean by author. The CES was developed and validated by Simson and Marek (1988). Teacher's misconceptions were investigated the way in which teachers marked students' work. The supposed answer given to the teachers to mark was based on misconceptions held by students tested in concept evaluation statements. The results of this study are as follows : 1. 0% of 7th Grade students, 4.5% of 9th Grade students and 5.4% of 11th Grade students understood homeostasis. There was a significant difference at the level of students' understanding of homeostasis according to schools and gender(P<0.05). Many students had a tendency of understanding the conception of the homeostasis by experiences and unscientific use of everyday language rather than a scientific concept. 2. 0.4% of 7th Grade students, 3.1% of 9th Grade students and 2.9% of 11th Grade students understood classification of animals and plants. There was a significant difference at the level of students' understanding of classification of animals and plants according to schools and gender(P<0.05). Students classified animals and plants through personal experiences and observations instead of trying to classify through microscopic analysis of animals and plants cell. 3. 1.2% of 7th Grade students, 10.3% of 9th Grade students and 19.4% of 11th Grade students understood food production in plants. There was a significant difference at the level of students' understanding of food production in plants according to schools and gender(P<0.05). Students had a misconception that food production in plants was done by an absorption of nutrients from soil not by photosynthesis. 4. A large proportion of teachers surveyed in this study appear to have misconceptions about homeostasis (38.1%), classification of animals and plants (34.1%), food production in plants (40.4%). The male teachers had. more misconceptions than female teachers(P<0.05). However, they didn't show any significant differences according to schools and teaching experience(P<0.05). 5. According to the investigation of teachers' perception, 29.8% of the teachers acknowledged that they might be a cause for students' misconceptions. This study shows that 38.3% of teachers did not understand the analyzed biological concepts precisely. By comparing the data of students and teachers, it turned out that teachers participate in the students' misconceptions. And teachers themselves acknowledged that students' misconceptions could be caused by them. Therefore. teachers' right understanding of fundamental biological concepts should precede to students' biology education. New training programs for biology teachers seem to be urgent.

• Korean Journal of Environmental Biology
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• v.30 no.2
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• pp.107-120
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• 2012

This study was carried out to illiminate the diversity of vascular plants by making list of rheophyte and hydorphyte plants at Yugu stream. This study was conducted from Aug., 2009 to Sept. 2010 at 7 points. Based on the voucher specimens, vascular plants from investigated areas were 88 families 229 genera 290 species 3 subspecies 30 varieties 5 forms, totally 328 taxa. Korean endemic plants were 3 species such as Forsythia koreana (Rehder) Nakai (planted) and Paulownia coreana Uyeki (planted), and Weigela subsessilis (Nakai) L.H. Bailey. The rare and endangered plants were designated by Korea Forest Service were 4 taxa, such as Penthorum chinense Pursh, Acorus calamus L., Lilium callosum Siebold & Zucc. and Iris ensata var. spontanea (Makino) Nakai. Floristic special plants were totally 26 taxa, which were grade V of 2 taxa, grade IV of 2 taxa and grade III of 9 taxa. Naturalized plants were 27 taxa, that was 8.3% of whole discovered vascular plants in this area. Even naturalized plants has not influence on the vegetation of Yugu stream. Since village was composed along the stream and the roads and banks were linked, naturalized plants were flowed continuously into this region. So, strategy of the conservation for this region should be designed. Based on flora, 3 types of group were discriminated such as main stream type (4 points), branch stream type (2 points) and reservior type (1 point). Each group has difference in composition of plants.

• Korean Journal of Plant Resources
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• v.21 no.4
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• pp.270-280
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• 2008

This study was carried out to clarify the distribution of vascular plants and their usefulness in Gongdeoksan of Mungyeong, Gyeongbuk (913m, N $36^{\circ}$ $46^{\prime}$ $37.5^{\prime\prime}$${\sim}$$36^{\circ}$ $43^{\prime}$ $61.0^{\prime\prime}$, $E128^{\circ}$ $15^{\prime}$ $00.3^{\prime\prime}$${\sim}$$128^{\circ}$ $17^{\prime}$ $57.9^{\prime\prime}$). The vascular plants collected 5 times (from May to September 2007) were consisted of total 429 taxa; 86 famailies, 279 genera, 374 species, 4 subspecies, 44 varieties and 7 forms. Among them, edible, medicinal, industrial, ornamental and usefulness unknown plants were 233 taxa, 297 taxa, 113 taxa, 111 taxa, 43 taxa, respectively. Korean endemic plants of this area were 5 taxa, and Law-protected plants by Ministry of Environment were 1 taxa, and the special plants species based on floral region by Ministry of Environment were 5 taxa in grade III category, 1 taxa in grade IV and grade V category. The naturalized plants were 15 taxa, therefore naturalized ratio was 3.5%, and urban index 5.5%.

• Korean Journal of Environmental Biology
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• v.40 no.1
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• pp.11-24
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• 2022

This study aimed to investigate the flora of Jinjosan Mt. (Uljin-gun, Gyeongsangbuk-do). The vascular plants were surveyed 9 times between March 2019 and April 2020. The results of this survey revealed a total of 414 taxa comprising of 87 families, 274 genera, 365 species, 12 subspecies, 32 varieties, and 5 forms. Among them, 9 taxa were Korean endemic plants and 5 taxa were rare plants of Korea. In addition, the specific plants by floristic region were 66 taxa including 1 taxon of grade IV, 18 taxa of grade III, 24 taxa of grade II, and 23 taxa of grade I. Additionally, eight taxa were classified as plants adaptable to climate change. Thirty-one taxa were of alien plants and three taxa were of ecosystem disturbance species, which were also investigated. The percentage of naturalized plants species and the urbanization index were estimated to be 7.5% and 5.0%, respectively. Our results provide basic data on vascular plants flora, and will guide the conservation processes of plant resources such as plant diversity and distributional changes in Jinjosan Mt.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.1-18
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• 2022

In this study, the vascular plants of the Mt. Deokhangsan protected area were surveyed for the purpose of forest genetic resources conservation in Gangwon-do, South Korea. The flora on Mt. Deokhangsan were classified as follows 537 taxa, 90 families, 302 genera, 479 species, 4 subspecies, 51 varieties, and 3 forms. Among the taxa, 19 were Korean endemic plants and 17 were rare and endangered plants. Plants as indicators of limestone areas were found in 33 taxa. Naturalized plants were found in 27 taxa and species threatened by climate change were found in 33 taxa, including 11 endemic plant taxa and 22 northern plant taxa. Plants endemic to Korea and northern plants were mainly found at the study site, whereas southern plants were not found. Thus, Mt. Deokhangsan apparently has an environment suitable for the growth of northern plants.