• Korean System Dynamics Review
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• v.7 no.1
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• pp.119-146
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• 2006

City of Gyeongju's referendum finally offered the long-waited low-level radioactive waste disposal site in November 2005. Gyeongju's positive decision was due to the various economic rewards and incentives the national government promised to the city. 300 million won for an accepting bonus, 8.5 billion won, annual revenue fro the entry quantity of waste into the city's disposal site, the location of the headquarter building of the Korean Hydro and Nuclear Power Co., and the accelerator research center. All of the above will affect the city's infrastructure and the citizens' economic and cultural lives. Population, land use, economic structure, environment and quality of life will be affected. Some will be very positive, and some will be positive. This research project will see the future of the city and forecast the demographic, economic, physical and environmental changes of the city via computer simulation's system dynamics technique. This kind of simulation will help City of Gyeongju's what to prepare for the future. The population forecasting of the year 2026 will be 289,069 with the waste disposal site, and 279,131 without the waste disposal site in Gyeongju. The waste disposal site and the relocation of the company headquarters and location of the accelerator research center will attract 9,938 individuals more with 511 manufacturing shops and 1944 service jobs. The population increase will bring 3,550 more houses constructed in the city. Land use will also be affected. More land will be developed. However, mad, water plant and waste water plant will not be expanded as much. The city's financial structure will be expanded, due to the increased revenues from the waste disposal site, and property tax revenues from the middle-class employees of the company, and the high-powered scientists and technologists from the accelerator research center. All in an, the future of the city will be brighter after operating the nuclear waste disposal site inside the city.

• The Korean Journal of Ecology
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• v.21 no.1
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• pp.27-33
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• 1998

Arisaema robustum, which has the ability to change sex, was studied in a temperate broadleaf forest of Sanseong-ri, Joongbu-myeon, Gwangju-gun, Kyonggi Province, Korea. \ulcornerThe study, carried out from 1993 to 1997, focused on population dynamics energy budget among organs, size distribution, mortality, the relationships between sex and size, seed production and germination rate. In terms of energy budget among the organs, the ratio of aboveground to belowground biomass was 36.6 : 63.4 in non-female plants, and 81.4 : 18.6 in female plants. Also, in female plants, the ration of leaf to sexual organ biomass was 39.5 : 41.9. Therefore, the belowground ratio of female plants was lower than that of non-female plants. Plants were classified into 8 levels relative to the amount of leaf area by $100cm^2$. The rates of the smallest and the largest classes were 49% and 1%, respectively, and population distribution by size was relatively stable. The mortality averaged 13.1% per year and decreased in inverse proportion to leaf size (6.6% in the smallest and 0.0% in the largest size classes). Leaf areas were $64.1{\pm}48.5cm^2$ in non-flowering plants, $232.1{\pm}123.9cm^2$ in males and $444.8{\pm}153.9cm^2$ in females. The increase rates of leaf area per year varied from 1.9% in plants changing from female tomale, to 152.4% in plants changing from non-flowering to female. But plants which remained female for 2 years showed a decrease of 34.7%. >From this result, it is thought that the female plants invest more energy to reproduction than to vegetative organs. The correlation coefficient (CC) value between plant size and the number of seeds produced (0.55) was larger than the CC value between plant size and total seed weight (0.73). That is, the larger the plant size, the heavier the seed produced. The germination rate increased along with seed weight, and it was 95% in plants which were over 60mg fresh weight/seed.

• Journal of Plant Biology
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• v.11 no.4
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• pp.9-20
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• 1968

In general there are few cases which were caused by lightening and no fire was observed to have been caused but by artificial or accidental fires during preliminary survey. And then the most scales of burning in Korea are like the fig. 2. Temperature 5 cm apart from flame at the burning site were known to range from 165$^{\circ}$to 20$0^{\circ}C$ in surface fire on Myozangdong, pine-quercus dominant community and from 120$^{\circ}$ to 145$^{\circ}C$ in surface fire of Wolwoonni, Mischanthus dominant area and from 120$^{\circ}$ to 14$0^{\circ}C$ in ground fire of Wangzinkun, Mischanthus dominant, respectively. Through the preliminary survey, fire indicater plants in Korea were confirmed as Mischanthus coreensis Hack and Carex alterifolia Franch. The plants of highest frequency appeared in the burnt sites were known to as Potentilla cryptotaeniae Max, Mischanthus coreensis Hack, Carex alterifolia Franch and Artemisia brachyphylla Kitamura. Lespedezas were proved as one of the fire tolerant and Pinus densiflora was found out as the lowest intolerant plant to fire. The acidity of burnt soil was decreased according to the considerable amount of ash left on the ground. The acidity of surface soil was more decreased than the below 10cm of soil. The chemical composition(NO3, P, K, Mg, Total-N and Organic-C) of burnt soil was more increased than those of the unburnt sites. And the population changes of soil microflora seemed to have a certain tendency. The population of soil microflora was increased a little according to climatic conditions. Also there was an initial decrease in the population of microflora followed immediately by a significant increase.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.422-439
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• 2019

The rear edge population is considered to have low genetic diversity and high risk of extinction according to a highly isolated distribution. However, the rear edge population is observed to have persisted for an extended period despite the low genetic diversity. As such, it is necessary to understand the ecological process involved in the persistence of the population. Viola mirabilis L. in Korea is considered the rear edge population from the perspective of the worldwide distribution. We surveyed the distribution range of V. mirabilis, which shows the isolated distribution in the central area of Korea, to find out the factors of its persistence. Next, we investigated and accessed the vegetational pattern of habitats, soil environment, phenology, self-compatibility, population structure, and extinction risk factors observed in the distribution area. V. mirabilis was distributed in the understory of the deciduous forest, planted forest of the deciduous conifer and deciduous broad-leaved trees, shrubland, and grassland in the limestone area. We also observed the re-establishment of seedlings in the population, and most of them showed a stable population structure. For chasmogamous flowers, the visit by pollinators has a significantly positive relationship with the production of fruits. However, we found that the production of the cleistogamous flowers was more numerous in all studied populations and that only the cleistogamous flowers were produced despite a more substantial plant size in some populations. The plant size was more related to the production of the cleistogamous flowers than that of the chasmogamous flowers. Accordingly, the cleistogamous flowers significantly contributed to seedling recruitment in the population. We found that the production of the chasmogamous flowers and the cleistogamous flowers did not have a correlation with the factors of the soil analysis except for phosphoric acid. V. mirabilis showed the self-incompatibility characteristics most likely due to the production capability of the cleistogamous flowers. Potential extinction risk factors observed in the distribution area was included the development of limestone mine, the expansion of agricultural fields, and the construction of houses. Although V. mirabilis showed an isolated distribution in the limestone area in the Korean peninsula, it showed a diverse distribution in a wide habitat environment ranging from the grassland to the understory of the trees with relatively low canopy closure rate. Moreover, we concluded that the persistence of the population was possible if we can maintain the current state of multiple populations and stable population structure.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.318-323
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• 1981

This study was conducted to establish an effective radiation treatment and selection method for induced mutants in M_1 population of soybean treated with gamma-ray. About 64% of total M_1 plants was reduced in plant height up to 50 - 60% and among which 60 - 70% of the plants were contained mutations in M_2 generation. About 60% of the MI plants have born 6 - 15 seeds per plant and 50 - 60% of their progenies produced mutants in M_2 generation. Positive correlation between plant height and number of seeds per plant in M_1 population was found. Higher visible macro-mutation rate in M_2 was observed in the groups of reduced plant height and seed number in the M_1 generation, whereas the frequency of chlorophyll mutation was increased in the group of less damaged plants. The size of mutation sector was increased with reduction in number of seeds per M_1 plant and the mutants were occurred at random in all the parts of M_1 plants. For the effective selection of mutants in soybean mutation breeding, the M_1 seeds should be harvested from the radiation damaged M_1 plants with the application of higher doses of mutagens, and handling M_2 generation by bulk population method is recommendable.

• Korean Journal of Plant Tissue Culture
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• v.27 no.4
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• pp.325-337
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• 2000

All living organisms depend on soil and water for their sustained growth and development. In recent years, sustenance of life in these growth matrices has been adversely affected by the cumulative increase in environmental pollutants resulting from increasing population, growing economies and resource-use. This review provides a glimpse into the problem of global environmental pollution, the traditional technologies available for remediation and the scope of emerging‘plant-based remediation’technologies. Phytoremediation, the use of plants to effectively remove or stabilize contaminants from the growth substrate, is a low cost and ecologically friendly alternative to the common‘dig and dump’technologies. The field of phytoremediation has been driven by the intrinsic need for identification of ideal candidate plant species. To date, there are only a very few identified plants which satisfy all of the prerequisites for use in phytoremediation. The review focuses on one such plant species, the common horticultural plant scented geranium (Pelargonium sp.), with demonstrated potential to remediate metal / salt contaminated soils / aqueous systems. The characterization of tolerance and metal / salt accumulation potential of Pelargonium sp. and its efficacy in remediating complex contaminated sites are described. The unique ability of scented geraniums to tolerate excessive amounts of multi-metals, hydrocarbon and salt mixtures, and at the same time to accumulate significant amounts of metal and salt ions in the biomass, renders this plant species as one of the ideal candidates for remediation.

• Journal of Plant Biotechnology
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• v.39 no.3
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• pp.169-174
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• 2012

Quantitative trait loci (QTLs), which were related to the ability of callus induction and plant regeneration in seed culture of rice, were analyzed using a mapping population from a cross between the rice cultivars 'Samgang' (tongil type) and 'Nagdong' (japonica). A tongil type rice cultivar, 'Samgang' showed lower frequency (20%) of plant regeneration than that (35%) of japonica rice, 'Nagdong'. Transgressive segregations were observed for the ability of callus induction and plant regeneration from the seed-derived calli of 58 doubled haploid (DH) lines. The ability of plant regeneration of 58 doubled haploid lines showed a continuous distribution with comparatively wide range (10.0 to 66.7%) of variation. Composite interval mapping analysis was used to identify the QTLs controlling callus induction and plant regeneration ability. Four significant QTLs, qCWS6, qCWS8, qCWS9 and qCWS11, associated with callus weight per seed were detected on chromosomes 6, 8, 9, and 11 with LOD values of 3.30, 2.60, 2.70 and 2.43, explaining 36% of the total phenotypic variation. Three significant QTLs, qPR1, qPR6, and qPR11, for the ability of plant regeneration were located on chromosome 1, 6, and 11 at LOD score of 2.25, 2.15 and 2.55, accounting for 24 % of the total phenotypic variation. The present study should be useful for improving the efficiency of plant regeneration in tissue culture of indica rice by means of marker-assisted selection.

• The Korean Journal of Ecology
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• v.18 no.2
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• pp.231-241
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• 1995

I examined the relationship between allocations to plant size components such as plant height, total leaf weight, and nuber of branches and to reproductive components such as the number and weight of male and female fowers in three populations of the monoecious, wind-pollinated Ambrosia artemisiifolia. In particular, the two types of gender of plants, phenotypic and functional gender, were related to resource allocation. Mean values of all plant size and reproductive components differed significantly among the three populations. Such inter-population differences did not exist for both photosynthetic and reproductive efforts, Plant size components were mostly positively correlated with reproductive components among plants. However, the relationships between photosynthetic effort and reproductive components were largely negative and inconsistent among populations. The phenotypic gender was much lover than 0.5 in all of the three populations. Pairwise correlations between functional gender and each allocation measurement such as plant size components, reproductive components, photosynthetic effort, and reproductive effort were not consistent across the three populations. These results suggest that the gender of A. artemisiifolia measured as flower production responds sensitively to environmental conditions which might differ whithin as well as among populations.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.622-624
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• 1998

During the course of study on plant parasitic nematodes associated with medicinal herbs in Korea, high population of different stages of citrus nematode, Tylenchulus semipentrans was found in association with Pyrola japonia Klenze in Imsil, Chunbuk province. The second stage larvae and males were isolated from rhizosphere soil ; immature and mature females were detached from the roots of infested plants of Pyrola japonica. Besides citrus it has been reported to parasitize on roots of Syringa vulgaris, Diospyros lotus, olive, grapevine, and pear in different parts of the world. This is the first record of T. semipenetrans parasitized on a medicinal plant, Pyrola japonica.

• Journal of Applied Biological Chemistry
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• v.43 no.4
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• pp.192-196
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• 2000

The molecular basis of plant adaptation to the environment is one of the most complex areas of plant science and an understanding of this subject is critical to our ability to feed an increasing word population. Research on plant adaptation to the environment often involves two complementary approaches; top-down studies of well-adapted plants with the goal of identifying and describing the biochemical basis of adaptation and bottom-up targeted analysis of specific biochemical mechanisms with the goal of understanding how these mechanisms contribute to overall plant performance. This brief review will provide examples of both of these approaches by describing the study of sorghum's adaptation to dry environments and the role of a blue light responsive chloroplast promoter that helps protect plants against damage by high irradiance.