• The Journal of Fisheries Business Administration
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• v.42 no.2
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• pp.85-96
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• 2011

Oliver flounder population density affect Oliver flounder growth and mortality rate. In laboratory pilot experiment, Oliver flounder growth rate is inversely proportional to stocking density. But previous study has not proved external validity. This study is aimed to analyze the effect of stocking density on the Oliver flounder culture farms in Jeju Island. In order to do this, I selected 13 farms in Jeju island as a sample. In the study, various analytical methods including productivity analysis, regression analysis, statistical analysis were conducted for 13 Oliver flounder culture farms. The result of analysis can be summarized as follows. First, in case of the Oliver flounder culture farms, Bertalanffy equation is not applicable to the Oliver flounder growth. Second, the Oliver flounder stocking density, defined as the surface area of Oliver flounder per $m^2$ of water surface area, is preferred to density definition defined as the weight of Oliver flounder per $m^2$ of water surface area on the Oliver Flounder Culture Farms case. Third, growth rate and production weight on the Oliver flounder culture farms are inversely proportional to stocking density on spearman rank correlation test. When extensive comparable biological and culture condition data become available, analysis model can be easily modified to yield more accurate results.

• Journal of Life Science
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• v.13 no.6
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• pp.889-895
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• 2003

This experiment was carried out to investigate the effect of subirrigation of Dolrido on the growth and development of stem cutting and young roes plant. Plant growth was measured at 20, 40, and 60 days after subirrigation of Dolrido. Plant height, stem diameter, number of leaves, leaf area and root length of cutting rose subirrigation were more affected than those of control. The growth of young seedling was significantly affected by subirrigation of Dolrido. Plant height, number of leaves, stem diameter, leaf area, fresh and dry weight were increased with subirrigation of Dolrido. However, T/R ratio was not affected by subirrigation of Dolrido. Growth of seedlings was promoted after 60 days treatment of Dolrido.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.3
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• pp.163-172
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• 2015

This study examined the potential effects of urban growth on streamflow in the Gyungan River watershed, Korea, using urban containment scenarios. First, two scenarios (conservation and development) were established, and SLEUTH model was adapted to predict urban growth into the year 2060 with 20 years interval under two scenarios in the study area. Urban growth was larger under scenario 2, focusing on development, than under scenario 1, focusing on conservation. Most urban growth was predicted to involve the conversion of farmland, forest, and grasslands to urban areas. Streamflow in future periods under these scenarios was simulated by the Soil and Water Assessment Tool (SWAT) model. Each scenario showed distinct seasonal variations in streamflow. Although urban growth had a small effect on streamflow, urban growth may heighten the problems of increased seasonal variability in streamflow caused by other factor, such as climate change. This results obtained in this study provide further insight into the availability of future water resource and can aid in urban containment planning to mitigate the negative effects of urban growth in the study area.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.3
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• pp.35-45
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• 2003

This study was performed to suggest growth status data of the large old trees as the natural monuments of Korea. Field investigation of 70 large old trees as the natural monuments of Korea was carried out in Seoul, Inchon, Kyungki, Chungbuk, Chungnam, Chonbuk, Chonnam. The main field of this study is classified into the growth condition, soil state and management situation. The results of this study are below : The age distribution of the large old trees as the natural monuments of Korea is as follows : above l00years in 5.9%, above 200years in 8.9%, above 300 years in 11.8%, above 400 years in 16.2%, above 500 years in 16.2% and above 600years in 41.1%. Location types of the large old trees as the natural monuments of Korea are found in 11 types; the types are hill side(22.9%), historical monument area(15.7%), field(l4.3%) and building area(12.9%), etc. Also, growth type of the trees is individually placed. In the aspect of soil environment, the acidification of soils has been appearing in all surveyed areas, and the soil of Seoul area has much acidum phosphoricum because of excessive fertilizer. Finally, in management situation. major factors inhibiting growth of the large old trees as the natural monuments of Korea are soil covering of protruded root above ground, soil hardening by human, embankments, small area that has been surrounded fence. Continuous monitoring and accumulation of status data are necessary to preserve the large old trees as the natural monuments of Korea.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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• pp.52-57
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• 2007

Growth promotion of wild plants by some plant growth-promoting rhizobacteria (PGPR) was examined in the microcosms composed of soils collected separately from a grass-covered site and a nongrass-covered site in a lakeside barren area at Lake Paro, Korea. After sowing the seeds of eight kinds of wild plants and inoculation of several strains of PGPR, the total bacterial number and microbial activity were measured during 5 months of study period, and the plant biomasses grown were compared at the end of the study. Acridine orange direct counts in the inoculated microcosms, $1.3-9.8{\times}10^9\;cells{\cdot}g\;soil^{-1}$ in the soil from the grass-covered area and $0.9-7.2{\times}10^9\;cells{\cdot}g\;soil^{-1}$ in the soil from the nongrass-covered site, were almost twice higher than those in the uninoculated microcosms. The number of Pseudomonas sp., well-known bacteria as PGPR, and the soil dehydrogenase activity were also higher in the inoculated soils than the uninoculated soils. The first germination of sowed seeds in the inoculated microcosm was 5 days earlier than the uninoculated microcosm. Average lengths of all plants grown during the study period were 26% and 29% longer in the inoculated microcosms starting with the grass-covered soil and the nongrass-covered soil, respectively, compared with those in the uninoculated microcosms. Dry weights of whole plants grown were 67-82% higher in the inoculated microcosms than the uninoculated microcosms. Microbial population and activity and growth promoting effect by PGPR were all higher in the soils collected from the grass-covered area than in the nongrass-covered area. The growth enhancement of wild plants seemed to occur by the activities of inoculated microorganisms, and this capability of PGPR may be utilized for rapid revegetation of some barren lands.

• Journal of People, Plants, and Environment
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• v.22 no.6
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• pp.575-582
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• 2019

Moss is used as an important material in indoor landscaping as well as outdoor landscaping. Moss is vivid green during growth and excellent in ornamental value. But when temperature drops, moss stops growth, turns brown or loses its ornamental value. In the present experiment, for the purpose of classifying native mosses according to the growth response to low temperature, the temperature of the plant growth chamber was set to 15℃/5℃ (16h/8h, day/night) and 5℃ (24h) for 8 weeks using nine native moss species. Thereafter, the temperature of the plant growth chamber was set to 20℃, and then the changes of moss block area and moss color were measured. The changes of moss block area and moss color were measured using a Photoshop program, after each moss block was photographed. As a result, Atrichum undulatum (Hedw.). Beauv., Etodon luridus (Griff.) A. Jaeger, Bachythecium plumosum (Hedw.) Schimp, Plagiomnium cuspidatum (Hedw.) T.J. Kop, and Hypnum plumaeforme Wilson showed a small decrease in moss block area at low temperature, and their recovery were the fastest at 20℃. These three species had higher green values at low temperature compared to other species, and the greenness increased rapidly at 20℃. On the other hand, Atrichum undulatum (Hedw.). Beauv., Marchantia polymorpha L., and Thuidium cymbifolium (Mitt.) A. Jaeger showed the smallest block area at low temperature and the lowest recovery even at 20℃. Their green values also decreased significantly at low temperature, and maintained low green value even at 20℃. These results showed that these three moss species are sensitive to low temperature. The remaining Myuroclada maximowiczii, Plagiomnium cuspidatum, and H. erectiusculum showed moderate responses to low temperature compared to other six species of mosses.

• Journal of the Korean housing association
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• v.14 no.6
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• pp.15-22
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• 2003

The regeneration of built-up areas is considered as one of the necessary measures for the effectiveness of urban growth management. In this vein, this study explores how to limit the number of people who leaves the built-up areas and to restore the area with the resident. For this, a residential area of the built-up area is analyzed in terms of why people in that area are moving out of the area and who fills in it after all. This study founds that narrow roads in a residential area and the changes in land use from residential purposes to commercial are major forces that push the people in the built-up area. In addition, the lack of welfare facilities, the pavement of roads, and pedestrian roads. education. crime. the lack of interaction between neighbors, and the quality of housing are all emerged contributing the loss of people in the built-up areas. It is recommended that all the factors here should be restored in an appropriate way. Another finding is that those who fill in the built-up area are largely over 50, self-employed, comparably wealthy, and having their own families. Hence, it is advised that the built-up area would be rearranged in order to attract those type of people in there.

• Journal of Construction Engineering and Project Management
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• v.2 no.4
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• pp.32-41
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• 2012

In recent times, multi-centralization and decentralization as well as large Capital area and suburbanization in the spatial structure of capital area. With rapid growth, urbanization and industrialization are unsystematic, and growth inequality between regions caused negative effects such as discordant centralization and decentralization, fluctuating land value, and gap between living conditions. Accordingly, this study analyzed urban spatial indexes by the self-governed body in the capital area such as Seoul, Incheon, and Gyeonggi province for the analysis of the regional inequality phenomenon. We examined the characteristics of temporal and spatial changes in urban spatial structure in the capital area by utilizing the distribution pattern and density of city indexes such as population, employment, etc, and then drew the commonality of those factors through factor analysis. We evaluated the drawn results through the city standard index by each city, conducted factor score analysis, and identified the interaction between each factor and Housing Purchase Price Composite Indices index, housing rent price index(Housing Jeonse Price Composite Indices), land price fluctuation rate, diffusion ratio of house, and financial independence.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.313-326
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• 2023

Owing to adverse weather conditions, there is a heightened focus on actively researching the regulation of the sowing date in field crop cultivation. Soybean, a prominent field crop with extensive acreage and production, is a photophilic and thermophilic crop characterized by short-day photoperiodism. Identifying the optimal sowing time is crucial for mitigating the effects of severe weather conditions on soybean yield. Precise control over the timing of soybean sowing is the key to minimizing yield reduction due to unfavorable weather conditions. Temperature, photoperiod, and their interplay are the most significant factors influencing soybean cultivation among various weather factors. We conducted an experiment using three Korean soybean cultivars with varied maturities (Hwangkeumol: early maturing and Daewonkong and Pungsannamulkong: late maturing) in 2013 and 2014. Our investigation covered aspects of soybean growth, development, yield components, isoflavones, and visual seed quality. Across all three varieties, isoflavone levels increased with later sowing dates, while other measured components exhibited significant variations based on the sowing date. This study also provides valuable insights for the selection of suitable cultivars that perform well in soybean cultivation at various durations of maturity.

• Journal of Plant Biology
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• v.15 no.2
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• pp.7-19
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• 1972

The studies of density effect or the effect of population density on plant growth have been done on basis of dry matter production with Raphanus acanthiformis var. simoodaeguen, Brassica campestris var. Pekinensis f. namsounsokoombecheu, Oryza sativa f. kimmajae and O. sativa f. mangyeng grown in the various spacing. 1. In the early period of plant growth in dry weight was not different each other among varying densities, but as time advanced the plant grown vast space grew sufficiently compared with those of narrow one. 2. Iogarithmic relation between the growth of plant (W) and the density (P), log W-log P in the material plants, were approximated by two straight lines, one was horizontal line and another inclined: the former showed non-competition density and the latter competition density addition to these the point interlinking both lines were implied of the optimum density per unit land area at certain growth period. 3. The values of relatvie growth rate (RGR) and net assimilation rate (NAR) were decreased as increase in the density, while those of leaf area ratio (LAR) were rather increased in the same condition, with minor exception. From these results and relation between the productive structure and due to lack of the recieved light intensity owing to the mutal shading among the plants.