• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.6
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• pp.72-81
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• 2002

The purpose of this study is to determine the impact of the soil load for artificial ground on a building's structural expenses. Three types of soil - 100% soil, soil mixed with 50% perlite, and 100% artificial soil - were used for this study. A one story concrete steel building specific to each soil load was designed, and then, the cost of steel and concrete used for the design was estimated. As the result of this study, the structural expenses in the case of 5:5 mixed soil can be reduced about 17% compare with 100% soil. Using artificial soil, the structural expenses can be cut about 32% compare to 100% soil and about 12% less when 5:5 mixed soil is used. However, considering total expense which includes the structural expense and soil expense, the expense of 5:5 mixed soil have an increase 25% compared with 100% soil. In the artificial soil, the total expense is 45% more expensive than 100% soil and 17% higher when 5:5 mixed soil is used because of the high unit price of artificial soil. This study expected substantial savings in structural cost as the soil-load was lightened. But, savings were significantly reduced because the unit price of the artificial soil is much more expensive than the price of the natural one. Therefore, further research on methods of reducing the unit price of the artificial soil should be conducted in order to extend green space on to artificial ground.

• Journal of Environmental Science International
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• v.29 no.4
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• pp.395-402
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• 2020

This study was conducted to analyze seasonal variations of de-icing salt ions harvested from soils and plants according to salt damage of Pinus densiflora f. multicaulis, a evergreen conifer, on roadsides. Pinus densiflora f. multicaulis was divided into three groups referred to SD, ND, and WD (serious salt damage (SD) = 71-100%, normal salt damage (ND) = 31-70%, and weak salt damage (WD) = 0-30%) based on the degree of visible foliage damage, and measured acidity (pH), electrical conductivity(EC), and de-icing salt ions (K⁺, Ca²⁺, Na⁺, and Mg²⁺) harvested from soils and plants. The results indicated that acidity, electrical conductivity, and de-icing salt ions of soils and plants were significantly affected by seasonal variation and salt damage. In addition, a strong positive liner relationship was observed in plants between the concentration of de-icing salts and salt damage in spring, while the relationship among seasonal variation and salt damage in soil were not significant. The results from this study has important implications for the management of conifer species in relation to salinity and roadsides maintenance.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.3
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• pp.113-121
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• 2018

The objectives of the research were 1) to develop the low-cost and high efficient desalination system to treat brackish water having high salt contents for irrigation at greenhouses near coast, and 2) to monitor and assess the effects of the brackish water desalination system on soil environment and growth in squash greenhouse cultivation area. The monitoring site was one of the squash greenhouse cultivation farm at Choengam-ri, Jinsang-myun, Gwangyang-si, Jeonnam-Do Monitoring results for groundwater irrigation water quality, and salinity showed a remarkable difference between control and treatment group. The salinity of soil at treatment group was less than at control group. While, the system made possible to increase the squash quantity from 4.7 ea to 6.3 ea at each and the average weight of the harvested squash was increased from 277.2 g to 295.1 g. The applied brackish water desalination system may be appled to reclaim sea or brackish irrigated area as alternative water resources, although long-term monitoring is needed to get more representative results at different level of salinity.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.161-164
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• 2010

Dollar spot, caused by Sclerotinia homoeocarpa F.T. Bennett, is the most economically important turfgrass disease on golf courses in North America due to its persistent nature. Fungicides, plant growth regulators, and other products were evaluated for preventative control of dollar spot and the secondary effects on brown patch and Pythium in a mixed stand of creeping bentgrass and annual bluegrass golf course putting green. Most fungicides provided excellent control of dollar spot throughout the trial but Rhapsody alone did not provide adequate control. Civitas applied alone and tank-mixed with Banner MAXX(R) and Daconil Ultrex(R) provided acceptable control throughout the study. No phytotoxicity was observed on any of the treatments applied but a darker green color and reduction in turfgrass growth was observed in a treatment with plant growth regulator, Trimmit. Treatments that contained Civitas and the Civitas Harmonizer also exhibited green pigmentation.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.2 s.109
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• pp.32-47
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• 2005

This study was carried out to investigate and propose a green-wall system with evergreen plants for urban greening of Tongyeong City. To achieve these goals, the requirements and possibilities for wall greening were investigated and evaluated considering the location, topography, and climate of Tongyeong City. Existing walls were analyzed and then a suitable green wall system is proposed. Tongyeong City and its 151 islands covers the central and the southern parts of the Goseong peninsula. Most of the land is covered with hills and mountains; $43.9\%$ of the land area has a slope greater than $15\%$ and most hills and mountains near the urban area have a slope of more than $30\%$. As a result of the topographical properties, concrete retaining walls can often be seen along the streets in urbanized areas. These retaining walls are not only unattractive, but they also create environmental problems, and thus should be replaced with native evergreen plants. Options for replacing the retaining walls include evergreen vine-plants such as Hedaa spp. and Euonymus radicans, but native evergreen shrubs such as Pittosporum tobira, Nandina domestica, Raphiolepis umbellata, Ilex cornuta, flex crenata, Fatsia japonic, and Aucuba japonica may be a more attractive option. Current wall conditions are unsuitable for planting vines, therefore, a reservoir-drainage-type plant box filled with a light artificial substrate is required for greening these concrete retaining walls. These might be irrigated in the dry season and fertilized annually by an appropriate system. These plant boxes could be attached along the entire walls. An experiment investigating effects of substrates and bark-chip mulching on the growth of Hedera spp. showed that the mixture of cerasoil and field soil(v/v, 4:6) was superior to field soil alone and to the mixture of perlite small grain, large grain, and field soil(v/v/v, 2:2:6). Bark-chip mulching tended to increase the growth of Hedera spp..

• Journal of the Korean Geotechnical Society
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• v.21 no.8
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• pp.45-53
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• 2005

Shallow slope failures in residual soil during periods of prolonged infiltration are common over the world. Therefore, this study examines an approximate method to estimate the influence of infiltration on surficial stability of slopes by one-dimensional infiltration model. Modified GAML model based on the Green-Ampt model was extended to predict the infiltration behavior of two-layered slope. Then, the model has been considered to evaluate the likelihood of shallow slope failure which is induced by a particular rainfall event that accounts for the rainfall intensity and duration for various return periods in two-layered soil profile. The results obtained from the approximate method were compared with those obtained from numerical analyses. According to the results, with the use of properly estimated input parameters, the proposed method was found to give good results that agree reasonably well to those of the more rigorous finite element analyses.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.137-141
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• 2002

Decomposition of green manure is necessary for the nutrient supply in farm soil. Hairy vetch as a green manure is superior to other winter legumes in terms of wintering ability and N accumulation. This experiment was carried out to investigate the decomposition and N release of hairy vetch and its effect on rice production as the following crop in paddy field. Decomposition of hairy vetch placed by soil depth of 0, 10 and 20cm at transplanting time was investigated by mesh bag method, which was enclosed chopped residue in mesh bags. The fate of $^{15}$ N derived from $^{15}$ N-labeled hairy vetch was investigated at harvest in three levels of N fertilization. Grain yield of the transplanted paddy rice cultured with hairy vetch as starter N were compared with that of applying urea as starter N in the field. Hairy vetch residue decomposed very rapidly both in transplanted and dry-seeded paddy field. In transplanted paddy field, hairy vetch residue lost 72-81 % and 86-90% of its weight after one and five month, respectively, as affected by incorporation depth. The C/N ratio of the decomposing vetch residue increased sharply during the early stages and after then, decreased slowly. The amounts of N and P released from the vetch were about 90% and 97% of initial content after one month, respectively. Recoveries of hairy vetch-$^{15}$ N by rice plant were 30.6, 34.6 and 35.7% in 0, 6 and 12 kg urea-N 10 $a^{-l}$ application, respectively, indicating that N fertilization increased the recovery of hairy vetch. $^{15}$ N. Hairy vetch residue incorporated as starter maintained significant N $H_4$$^{+}$-N concentration in soil water of plow layer until effective tillering stage. Grain yield in the plot applied with hairy vetch was not significantly different from that in the plot with urea. We concluded that hairy vetch incorporation could substitute starter N fertilization and showed possibility to reduce N amount of top-dressing.g.g.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.385-390
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• 2014

To evaluate the impact of nitrogen fertigation on crop growth and $NO_3$-N concentration in the soil solution, field experiment for cucumber cultivation during spring and fall season were carried out in on-farm located in Byeongcheon-myeon, Chunan-si, Chungcheonnam-do. Supplying nitrogen of 120-150 mg/L by fertigation device into soil per week reached to maximum yields of cucumber fruits. However, cucumber growth did not show any significant difference between nitrogen levels. Nitrogen supply of 400 mg/L, highest N levels, did not affect cucumber growth. Difference between green values of cucumber leaves using RGB scores were closely related with cucumber yields, and therefore, this results suggests that green values of cucumber leaves could be used as a way of determining the application rates of nitrogen for cucumber cultivation period under fertigation system.

• Journal of Environmental Science International
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• v.19 no.5
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• pp.585-590
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• 2010

This study attempted to facilitate various groundcover plants, related to phytoremediation material, and advance shade plants with a heavy metal tolerance to contaminated soil in an urban shade space. Saxifraga stolonifera, which has commonly been used a landscape shade plants, was evaluated to determine its heavy metal tolerance to different concentrations(Control, $100mg{\cdot}kg^{-1}$, $250mg{\cdot}kg^{-1}$ and $500mg{\cdot}kg^{-1}$ treatment) of Cd, Pb and Zn in soil. The growth of Saxifraga stolonifera showed no significant tendency after the initial transplantation, but showed distinct changes with the respective treatment heavy metal types and concentrations over time. Especially, severe chlorosis, with more yellowish green leaves, was observed, with inhibition at Cd concentrations greater than $100mg{\cdot}kg^{-1}$. Conversely, no external symptoms or growth retardation were observed with Pb and Zn concentrations less than $500mg{\cdot}kg^{-1}$. Therefore, Saxifraga stolonifera can be applied as a long term phytoremediation species in soil contaminated with low concentrations of heavy metal in urban shade spaces.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1058-1064
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• 2012

A green manure crop were used in many ways, such as for reducing chemical fertilizer, improving physical and chemical properties of soils, protecting soil loss, and creating landscape when it's grown in agricultural land. Experiments were conducted to find out carbon emitted with applying green manure crops in paddy field. Amounts of carbon absorbed in the green manure crops during the winter were 1.22 ton $ha^{-1}$ in hairy vetch, 1,24 ton $ha^{-1}$ in barley, and 1.54 ton $ha^{-1}$ in hairy vetch/barley. The soil carbon content was the highest at days before transplanting of rice and decreased after days after harvesting the plant. Soil carbon contents were higher with hairy vetch or barley treatment than with hairy vetch/barley treatment. The content of emitted methane ($CH_4$) was the highest at 7 days after transplanting rice plant, and was 17 ~ 25 times higher with green manure treatments than with chemical fertilizer application. The $CH_4$ emission was the highest with hairy vetch treatment and than followed by hairy vetch/barley and barley treatments. The content of carbon absorbed in rice plant increased during the cultivation period but was not different with the applications of different green manure crops. The yield amounts of rough rice and rice strow were 5 ~ 13% higher with the green manure treatments than the chemical fertilizer application. In particular, they were the highest with hairy vetch/barley treatment as 14.07 ton $ha^{-1}$.