• Journal of Environmental Science International
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• v.29 no.3
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• pp.229-240
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• 2020

This study was conducted to evaluate the effect of phosphorus acid (H₃PO₃) addition to the horticultural bed soil on the initial growth of red pepper (Capsicum annuum L. cv.), cucumber (Cucumis sativus L. cv.), and kimchi cabbage (Brassica campestris L. ssp. pekinensis (Lour.) Rupr. cv.). The stem heights of red pepper and cucumber were 46.1% and 23.0% greater in the 50 mg/L of phosphorus acid treatment than the untreated (control). Further, the stem diameter of pepper and cucumber were 48.7% and 23.0% greater in the 50 mg/L of phosphorus acid treatment than the control. In addition, the number of kimchi cabbage leaves was 47.5% greater in the 50 mg/L of phosphorus acid treatment than the control. The dry weights of red pepper, cucumber and kimchi cabbage were 72.9%, 16.5%, and 30.4% heavier in the 50 mg/L than the control, respectively. Cations (K, Ca, and Mg) and total phosphorus (T - P) were quantitatively analyzed for these three horticultural crops. The concentrations of K, Ca, and Mg, and T - P were higher in the 50 mg/L of phosphorus acid than the control, respectively. Based on the results obtained in this study, it appears that treatment of phosphorus acid in horticultural bed soil enhanced the growth of red pepper, cucumber and Kimchi cabbage.

• The Korean Journal of Food And Nutrition
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• v.8 no.1
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• pp.13-16
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• 1995

120 fungal strains producing Y-linolenic acid (GLA) were isolated from 100 soil samples, and among these, the most suitable one for the production of GLA was identified as Fusarium sp. JK-02. The content of total lipid and dry cell weight was 620mg 1100m1 and 63.5mg 1100m1, respectively. The production of GLA was 10.2% of the total fatty acids.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.5
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• pp.279-284
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• 2008

This study was performed to investigate effect of different soil managements on physical properties and microbial activities in volcanic ash citrus orchard soil. Experiment plots had managed to control weeds on soil for 4 years with clean cultivation (CCM) used with herbicide, natural sod cultivation (NSCM), kentucky blue grass sod cultivation (KBG). Soil samples were taken on October, in both 1998 and 2000 from 3 experimental plots. In NSCM, Soil hardness was lower at 11.8 mm than in CCM. And water stable Aggregation coefficient(>0.5 mm) was high at 26.7% compared with CCM. Soil bulk density and porosity showed no significant among the treatments. Soil acid phosphatase was high in sod cultivation plots and the amount of microbial biomass C was about twice higher at $525.4mg\;kg^{-1}$ in KBG than in CCM. Conclusionally, Sod cultivation improved soil physical properties such as aggregation, hardness and increased microbial activities compared with clean cultivation in citrus orchard soil. Soil total PLFA, acid phosphatase, and microbial biomass C contents were investigated on May in nonvolcanic ash citrus soil. Soil samples were collected at 5 sites each; convention cultivation grown with herbicide, natural sod cultivation grown with 1/2 chemicals, organic cultivation. That sites have been managed for 5 years over. PLFA contents were two times higher at $112.2n\;mol\;g^{-1}$ in organic cultivation than in convention cultivation. According to the PLFA indicator, Gram negative bacteria and actinomycetes in organic cultivation were high compared with convention cultivation, which were at 15.1%, 6.6%, respectively. Soil microbial biomass C contents was about twice higher in organic cultivation than in convention cultivation. Soil acid phosphatase was high at 17.6% in organic cultivation compared with convention cultivation.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.670-675
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• 2004

Humic acids are macromolecules originated from natural water, soil, and sediment. The characteristics of humic acid enable it to change the distribution of metals as well as many kinds of organic contaminants and to determine the sorption of them from soil solution. To see the effect of humic acid on the removal rate of organic contaminants and heavy metals, batch-scale experiments were performed. As a natural geosorbent, black shale was used as a sorbent media, which showed hight sorption capacity of trichloroethylene (TCE), lead, cadmium and chromium. The effect of sorption-desorption, pH, ionic strength and the concentration of humic acid was taken into consideration. TCE sorption capacity by black shale was compared to natural bentonite and hexadecyltrimethylammonium (HDTMA) modified bentonite. The removal rate was good and humic acid also sorbed onto black shale very well. The organic part of humic acid could effectively enhance the partition of TCE and it act as an electron donor to reduce Cr(VI) to Cr(III). Cationic metal of Pb(II) and Cd(II) also removed from the water by black shale. With 3 mg/L of humic acid, both Pb(II) and Cd(II) were removed more than without humic acid. That could be explained by sorption and complexation with humic acid and that was possible when humic acid could change the hydrophobicity and solubility of heavy metals. Humic acid exhibited desorption-resistivity with black shale, which implied that black shale could be an alternative sorbent or material for remediation of organic contaminants and heavy metals.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.869-877
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• 2000

A mechanism of ozonation of simulated soil slurry contaminated by phenanthrene and benzo[a]pyrene has been studied under various conditions. The effects of soil media(BS, S, GB), radical scavenger, ozone input ratio(0.17~0.73mg/min), bicarbonate ion, and humic acid were investigated, BS showed the highest removal efficiency in media tested. The generation of OH-radical via the catalytic decomposition of ozone on active sites of the natural sand was confirmed by OH-radical scavenger experiments. The enhanced removal efficiency by OH-radical was indirectly quantified to be about 22%. As initial concentration of humic acid(as sodium salt) was increased, pseudo first-order rate constant ($k_o$) of phenanthrene was decreased from $1.37{\times}10^{-2}s^{-1}$ to $0.53{\times}10^{-2}s^{-1}$. The amount of ozone required to oxidize 80% of the initial mass of phenanthrene(10mg/kg) and benzo[a]pyrene(10mg/kg) was 67.2mg/kg-soil and 48.0mg/kg-soil, respectively.

• Korean Journal of Organic Agriculture
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• v.19 no.2
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• pp.229-243
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• 2011

Consumers' interest and government's support for the fruits rapidly increased organic fruit productions. This study was examined to compare the soil physicochemical and microbial properties of orchards soil in conventionally and organically management systems. Organic cultivation had lower soil bulk density, solid phase, and penetration resistance than the conventional cultivation. Soil pH and organic matter contents increased from March to August, and the values were greater in the organic cultivation than the conventional cultivation. Total nitrogen (N) and phosphorous concentrations decreased from March to August, and the organic soils had greater N but lower phosphorous concentrations than the conventional soils. Soil microbial carbon biomass increased 36% and 15% for organic and conventional cultivations, respectively, from March to August. Soil microbial N biomass was greater in June than March or August, and the organic cultivation had a greater biomass N compared to the conventional cultivation. Soil dehydrogenase and chitinase activities were greater in June than in March or August. ${\beta}$-glucosidase activity declined in both cultivations, while the phosphatase activity increased. Organic cultivation had greater enzyme activities in March, June, and August, except for the acid phosphatase activity in June.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.533-539
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• 2014

Mine wastes such as acid mine drainage (AMD) can cause the detrimental effects on surrounding environment, thereby eventually threatening human health. Main objective of this study was to evaluate the neutralizing effect of fly ash (FA) as a stabilizing material AMD. Field plot was constructed in a coal waste depot which has caused aluminium-whitening adjacent to the stream. Different mixing ratios of FA were applied on a top of the soil, and then the physicochemical properties of runoff and soil were monitored. Constructed plots were as following: control (mine waste only (W)), mine waste + 20% ($w\;w^{-1}$)of FA (WC20M), mine waste + 40% ($w\;w^{-1}$)of FA (WC40M), and WC40M dressed with a fresh soil at the top (WC40MD). Result showed that initial pH of runoff in control was 5.09 while that in WC40M (7.81) was significantly increased. For a plot treated with WC40M, the concentration of Al in runoff was decreased to $0.22mg\;L^{-1}$ compared to the W as the control ($4.85mg\;L^{-1}$). Moreover, the concentration of Fe was also decreased to less than half at the WC40M compared to the control. Application of FA can be useful for neutralizing AMD and possibly minimizing adverse effect of AMD in mining area.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.1
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• pp.64-73
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• 2013

Because some particulate matter emission sources may inherently produce soluble species, or some soluble species may be produced during atmospheric transport, it is important to understand the origin of a particles's solubility when water-soluble tracers are used in source apportionment studies. Laboratory experiments were performed on three types of soils (Mongolia grassland, Mongolia desert, and Korean rural soils), to study the impact of acidification by nitric acid vapor on the solubility of metals in the soils. To achieve this goal, concentrations of water-soluble metals (Na, Mg, Al, K, Ca, Mn, and Fe) in the soils measured before and after acidification. Contributions of concentrations of water-soluble metal species before and after acidification attack to their total concentrations varied little with soil type. Concentrations of water-soluble Mg, Al, K, Ca, Mn, and Fe from the soils after interaction with nitric acid vapor increased, with significant increases in soluble Ca and Mn for all soil types suggesting soil acidification enhances the amount of leachable metal species in soil dust. There was little increase in water-soluble Na and K after acidification for each soil type. This experiment demonstrates that quantities of water-soluble metal species in particulate matter are produced under high gaseous nitric acid conditions.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.5
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• pp.102-118
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• 2004

The purpose of this study was to propose an ecological management plan by the comprehensive analysis of biotope structures on Namsan Urban Natural Park in Seoul. Classified by actual vegetation, structure of layer and vegetation damage, biotope structures were composed of forest area, compact management area, herb area, cultivated area and non-ecology(urban) area. Succession had seened to stop in the Native forest. Artifical forest was divided into two types. The first, upper layer, was too dense to accommodate lower layer plants, the other case was the appearance of Quercus spp. and the first stage plants of succession following the declination of the upper layer plants. The soil pH of Nam-san Urban Park was 4.21∼4.51, which meant the soil was becoming acid. As the result of acidity, leaching of available nutrition(K/sup +/, NH₄/sup +/, Ca/sup ++/ etc.) was immediately influenced by the natural ecosystem, influence of acid rain was disturbed to becoming organic matter which was use to plants. In the case of a biotope structure management plan, the urban area was prohibited to spread outside. Cultivated and herb area was regenerated to natural forest. In the forest area, the compact management area was maintained with its present condition, and then it is desirable to make a preservation area and to plant shrubs. Planted Pinus densiflora Community was needed to eliminate competitive species of canopy layer, and plant shrubs. Management of deciduous broad-leaved Comm. was maintained in its present conditionand it is desirable to raise the diversity of the understory and shrub layer. The management of the artifical forest seems to be suitable for Q. spp. community. The care of naturalized plants prevents the expansion and restores the structure of wild plants. The soil management was a marked restoration soil ecosystem in order to prevent soil acid and drying.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.54-62
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• 2004

In order to enhance the efficiency of removal a series of ElectroKinetic Remediation (EKR) tests on ferrous soil contaminated by lead are carried out using acids, chelates and surfactant as flushing agents. The test results indicate that pH in the electrolyte rapidly reached at steady state as the introduce of flushing solution of the lower pH, the type of flushing solution have no effect the distribution of electrical voltage within the sample but the increasing of solution concentration increases it at x/L=0.9. In the distribution of the residual lead in the sample SDS is the highest. Also, the removal efficiency for acetic acid concentration of 1mM Is the highest but the concentration of acetic acid significantly have no effect.