• Journal of Environmental Science International
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• v.14 no.6
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• pp.605-611
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• 2005

The aim of this study was to analyze the local distribution of the heavy metal concentration in Daegu and Ulsan which were divided into the residual areas, the traffic dense areas and the industrial areas. The Inductively Coupled Plasma(ICP) was used to analyze heavy metals, such as As, Cr, Hg, Zn, Cd, Pb, Cu and minor metals, such as Fe, Si, Mg, Ca, AI, Na, K. The results of this analysis showed that the content of heavy metals which was classified by districts in Daegu and Ulsan was the highest in the industrial areas followed by the traffic dense areas and the residual areas. Compared to the level of heavy metals of national and local soil survey network in 2003, contamination of heavy metals in Daegu was lower than national average. However, the content of Cd, As, Zn in Ulsan was respectively 13.38 times, 472 times and 2.65 times higher than national average contamination. In addition, compared to the soil pollution level of the environmental protection law, contamination of all areas in Daegu was lower. But the content of As at the industrial areas in Ulsan was 10.71 times higher than standard of soil pollution and 4.28 times higher than standard of measures against soil contamination.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.191-194
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• 2003

The purpose of this paper was to derive soil-water characteristic curve equation for unsaturated soil. To this end, a series of suction measured test was conducted on the selected 4 kinds of soil which is located in Korea, used the modified pressure plate apparatus. From the test results, it was proved that characteristic curve changes according to grain size distribution, size of void and fine grained soil contents. Residual degree of saturation(Sr) was decreased with void ratio and changed with fine grained soil contents, parameter ${\lambda}$ and hr was increased with void ratio. Soil-water characteristic curve equation based on the test result was suggested by void ratio or grain size distribution.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.606-611
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• 1999

Recently , the hydraulic fill method is commonly used in many reclamation projects due to lack of fill materialss. The method of hydraulic fill i recalmation is executed by transporting the mixture of water -soil particles into a relcaimed land through dredging pipes, then the dredged soil particels settle down in thewater orflow over an out flow weir with the water. The amount of the volume reductions of dredged soil is considered the sum of the overall settlement by descication shrinkage and self-weigth consolidation and the loss of soil particles flow over a weir. In the present study, hydrometer analysis was performed with the soil samples obtained bofore and after dredging to estimate the amount of soil particles residual at reclaimed area and the loss of soil particles , then it was suggested the method of determining the loss ratio of dredged soils from the tests results. The hydrometer analysis of in-situ soil samples showed that the loss ratio of dredged soils is lowest at the nearest point to dredge pipe and highest at the nearest point of out flow weir.

• Journal of the Korean Geotechnical Society
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• v.36 no.1
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• pp.5-15
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• 2020

Dynamic behavior of pile foundation is significantly influenced by the dynamic interaction between soil and pile. Especially, in the sloping ground, the soil-pile interaction becomes very complex due to different resistance according to loading direction, soil residual displacement and so on. In this study, dynamic centrifuge tests were performed on the piles in the sloping ground. The model structures consisted of a single pile and 2×2 group pile. The soil-pile interaction has been investigated considering various conditions such as slope, single and group piles, and amplitude of input motions. The phase differences between soil and pile displacement and dynamic p-y curves were evaluated. The analysis results showed that the pile behavior was largely influenced by the kinematic forces between soil and pile. In addition, the dynamic p-y curve showed the complex hysteresis loop due to the effect of slope, residual displacement, and kinematic forces.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.446-452
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• 2000

This study was carried out to investigate the effect of mine activity on paddy fields, agricultural water, and plants in the ruined Oksung Cu-Zn mine area. Soil samples collected from paddy fields adjacent to the Cu-Zn mine sites were sequentially extracted and determined the contents of heavy metals such as Cd, Zn, Cu, Pb, Cr and Ni. Distribution of exchangeable heavy metals in soils was 30.2% of Cd, 11.3% of Zn, 2.2% of Cu, 4.6% of Cr, 0.6% of Pb and 3.9% of Ni. Water soluble heavy metals were only detected with Zn. The contents of heavy metals in water collected from the mine were 0.01 of Cd, 27.35 of Zn, 4.86 of Cu, 1.04 of Pb, 0.03 of Cr and $0.08mg\;L^{-1}$ of Ni. while the contents in waler collected out of the mine were 16.67 of Zn, 0.59 of Cu, 0.49 of Pb, 0.05 of Cr and $0.06mg\;L^{-1}$ of Ni. On the other hand, agricultural water near mine area were 1.26 of Zn, 0.05 of Cu, 0.05 of Pb and $0.02mg\;L^{-1}$ of Ni. Both Cd and Cr were not detected in the agricultural water.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.290-293
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• 2000

After kaolin clay was compulsorily contaminated with Co$^{2+}$ion, the remediation characteristics by electrokinetic method were analyzed. Ethanoic buffer was injected in the soil column and $CH_3$COOH was continuously inputted in cathode reservoir to restrain the pH elevation. Since pH of the cathode side of the soil column was 4.0 at initial and was restrained by 6.5 at 43.6 hours, Precipitation, Co(OH)$_2$, was not formed in the column. Effluent rate increased with time passage and remediation in the column in initial time was mainly controlled by ion migration. 13.1% of total in the soil column was remediated in 10 hours, and the 6.8% of total in 20.8 hours, and the 71.7% of total in 43.6 hours, and the 94.6% of total in 43.6 hours. Meanwhile, the residual concentrations in the column calculated by the developed model were similar to those by experiment.t.

• Geotechnical Engineering
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• v.2 no.1
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• pp.7-14
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• 1986

The structure of the collapsible soils, such as decomposed granite soil and loess, were examined by the odeometer test, SEM & XES analysis and static & cyclic triaxial test, and hove this structure have influences upon the collapsible behaviour under static and cyclic load was investigated. The study results obtained are as follows; 1. The macropores space of decomposed granite soil (rd=1.50g/cm3) and loess (rd=1.43g/cm3) used in this test were well developed, and showed the behaviour of collapsible soil. 2. Collapsible soil has high resistance on the strain under natural moisture content, however, the resistance on the strain was sharply decreased by the absorption and increasing load since its special structure was destructed. 3. Under the static load, the strain of collapsible soil was high by the viscous flow of the cyclic bonds with time lapse, but Infer the cyclic load, the strain of collapsible soil was low since the tinge needed to destruct the bonding force of clay was not enough. 4. The understanding about the cyclic behaviour of collapsible soil may be helpful to predict the elastic & residual strain of the foundations by the earthquake together with the damage by the additional failure.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.1
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• pp.22-27
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• 1991

This study was designed to find out the effects of cropping patterns on the changes of soil physico-chemical properties. Soil properties and crop growth were studied under the four cropping patterns, such as rice monoculture, green garlic-rice, manure rye-rice and radish-rice. The results are summurized as followings ; 1. Soil physical properties were affected by different pre-crop cultivations and its residual effects were continued for 60-70 days after rice transplanting 2. Soil air permeabilities at harvesting time of pre-crops were high in order of manure rye>green garlic>radish, and water permeabilities during rice cultivation were similar to previous order. 3. Chemical properties of soil were affected by the different fertilizer level of pre-crops and their residual effects were continued to rice harvesting time. The ratio of nutrient uptake to $N-P_2O_5-K_2O $ based on amount of application were in the order of manure rye-rice>radish-rice>rice monoculture>green garlic-rice plot. Fertilizer application after pre-crops cultivation must be considered. 4. Rice root distribution of manure rye-rice plot was higher than that of other cropping patterns at subsoil. However, rice root distribution at green garlic-rice plot and radish-rice plot was high at topsoil which had much residual nutrient from pre-crops. 5. Rice yield after pre-crops was high in order of green garlic-rice>radish-rice> rice monoculture>manure rye-rice.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.2
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• pp.111-115
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• 1989

In order of remove Cd by plants cultivation in the cadimum contamination soil, six fibers, four flowering and two sapling plants were cultivated at Cd treated soil, adjusted to 15 ppm. The Cd contents of plants and absorbed Cd concentration in plant, and residual Cd in soil were analyzed. The results obtained are as follows: 1. The Cd content in marigold was the highest, 161.7ppm, 22.5 times higher than rice. The Cd contents in plants was in the order of 58.3 ppm in sedge, 58.0 ppm in coreopsis, 43.5 ppm in sunflower, 38.3 ppm in scruber, and 31.9 ppm in flax. 2. The absorbed Cd in Popuaus alba x P. glandulosa was the highest, 24.11 mg/pot, 35.5 times higher than rice. The absorbed Cd by plants were in the order of 10.86 mg/pot in italianpoplar, 9.61 mg/pot in marigold, and 9.04 mg/pot in kenaf. 3. The residual Cd contents was the lowest in Popuaus alba x P. glandulosa soil and cotton followed. 4. Absorbed Cd dontent in plants was negatively correlated with the residual Cd concentration in soil.

• Journal of Applied Biological Chemistry
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• v.60 no.4
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• pp.301-306
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• 2017

This study was carried out to investigate the residual level of 5-methyl-1,2,4-triazolo[3,4-b][1.3] benzothiazole (tricyclazole) and the amount of transfer to Korean cabbage grown in treated soil with tricyclazole. The field trial on Korean cabbage was done at two different green houses located in Gwangju (Field 1) and Yongin (Field 2). Soil and cabbage samples were collected at different days after soil treatment of tricyclazole with two different concentration levels, respectively. Average recoveries of tricyclazole ranged from 83.5 to 92.1% in soil and cabbage and the variation coefficient was 1.3-6.8%. The initial concentrations of tricyclazole in field 1 soil were 4.25 and 8.97 mg/kg and decreased to 2.48 and 4.26 mg/kg at 43 DAT (day after treatment) and 0.88 and 2.02 mg/kg and decreased to 0.43 and 0.98 mg/kg at 36 DAT in field 2, respectively. The half-life of tricyclazole was about 39.6 and 28.1 days for the low and high concentration of tricyclazole treated soils in field 1 and 27.9 and 17.2 days for the low and high concentration of tricyclazole treated soils in field 2, respectively. Residual levels of tricyclazole in Korean cabbage were ranged from 4.03 to 18.26 and from 8.26 to 35.08% of initial concentration in filed 1 and field 2 soils, respectively.