• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.396-399
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• 2006

This study was conducted to investigate the desalinizing effect of some vegetable crops (beet, crown daisy, kale, lettuce, spinach, sweet com, and tomato) in salinized soil. The soil was treated with highly concentrated nutrient solutions and the growth of these crops was compared and soil salinity was monitored. The plant height of lettuce and crown daisy inhibited severely in with EC $5dS{\cdot}m^{-1}$ salinized soil. Soil EC level was the lowest in soil where tomato was cultivated followed by corn and kale. The residual level of $NO_3$ was higher in soils used for cultivation of corn, tomato, and kale, that of K was higher in soils used for cultivation of corn, tomato, and beet, and That of $P_2O_5$ was higher in soils used for cultivation of corn and tomato. Although the desalinizing effect was greatest by tomato and corn after 60 days of cultivation. Quality of the these crops was low and the cultivation periods of these crops overlapped with that of the main crops. Kale, on the other hand showed less growth inhibition in salinized soil, greatest desalinating effect based on fresh weight. In addition this crop only needs 30 days of cultivation period. Therefore, kale was most efficient crop in desalinizing considering crop quality, a short cultivation period, and nonoverlapping cultivation time with the main crops.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.422-430
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• 2000

Three-year-old Pinus koraiensis seedlings, transplanted in brown forest soils originating from granite were treated with simulated acid rain of pH concentrations 5.6(control), 4.0, 3.0, 2.5 and 2.0 for 210 days from April 21 to November 17, 1999. Visible injury of the seedlings were observed at the pH 2.0 and pH 2.5 treatments. The total dry weight of the seedlings decreased at pH 2.0 treatment compared with that of the control, and T/R ratio increased at pH 2.0 treatment compared with others. The elements in each part of the seedlings, concentrations of Ca, P and content of chlorophyll in needles increased at the pH 2.0 treatment compared with the control. The concentration of N in the needles of the seedlings increased as the soil pH decreased. As the treated pH was lowered, soil pH has decreased, and concentrations of Ca, Mg, Al, and Mn increased, especially at pH 4.4. In addition, there was a strong correlation(r=0.90, p<0.05 ; r=-0.94, p<0.01) between the dry weight of the seedlings and the pH and Al concentration of the soils. Therefore, the pH and Al concentration in the soil may be useful indicator for assessing the effect of acid rain on the growth of woody plants.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.11-20
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• 1998

Inorganic nitrogens resulting from fertilizers are possible contaminants of bank-filtered ground water, which is an alternative source of safe drinking water. We conducted a laboratory study to determine the fate of inorganic nitrogens in the near field of bank filtration sites and we consequently illustrated the effects of these possible contaminants on the water quailty of bank filtration. Soil properties were found to be well equivalent to those of other cultivated field soils in Korea. Surface soil pH was about 4.3 which is slightly lower than average level. Overall, diverse concentrations of $NO_3$-N and $NH_3$-N were measured, and $NO_2$-N was nearly undetected. $NH_3$-N level in the field decreased, while $NO_3$-N increased along with increasing depth of unsaturated zone. Numbers of viable and nitrifying bacteria ranged from 6.73$\times$$10^{6}$to 10.7$\times$$10^{6}$ and 0.44$\times$$10^{4}$ to 5.21$\times$$10^{4}$ respectively, and both of them were highly correlated ($R^{2}$=0.992). Nitrifying potential assayed by batch test showed relatively lower than other reported results. The oxygen uptake potential of surface and subsurface soil was measured in the presence of ${(NH_4)_2}$$SO_4$. The results demonstrated that surface soil required shorter lag period and uptaked more oxygen than subsurface's.

• The Journal of Engineering Geology
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• v.33 no.1
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• pp.39-49
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• 2023

Soil contaminants measured and managed in Korea include those of geologic origin such as arsenic, cadmium, copper, lead, zinc, nickel, mercury, and fluoride. This study identifies the distribution of these contaminants using GIS modeling to analyze the spatial probability of soil contamination originating from geology. The modeling found that cadmium, copper, lead, nickel, and mercury often exceed the regulated standard by <1%. Concentrations of arsenic and zinc greatly exceeded the standard in the vicinity of mines and industrial complexes: mining and industry seemed to have substantial effects on the concentrations of these metals. Although fluoride was sampled at the lowest number of points, its frequency of exceeding the standard was the highest. No obvious source of artificial contamination has been identified, and fluoride's distribution characteristics showed continuity over a wide area, suggesting a strong correlation between geological characteristics and fluoride concentration. The highest frequencies of fluoride exceeding the standard were in Jurassic granite (40.00%) and Precambrian banded gneiss (34.12%). As these rocks contributed to the formation of soil through their weathering, high fluoride concentrations can be expected in soil in areas where these rocks are distributed.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.304-314
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• 2010

This study was carried out to find out potential use of ochre as an agent to reduce phosphorus content in water. Ochre is a by-product from treatment of acid mine drainage (AMD) which is composed mostly of $Fe_2O_3$, $Fe_2O_3{\cdot}H_2O$, $FeO{\cdot}OH$ and $Fe(OH)_3$. Three ochre samples (ochre-H, ochre-D and ochre-S) were collected from three treatment facilities in Gangwon province. Physico-chemical characteristics of three ochre samples including pH, electrical conductivity, total phosphorus, available phosphorus, particle size distribution were analyzed. Scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and X-ray fluorescence (XRF) analysis were also carried out. In addition, experiments for phosphorus removal from water was performed. Calcium content of ochre-H was higher than that of ochre-D and ochre-S, whereas iron content of ochre-H was lower than that of ochre-D and ochre-S. All the phosphorus in water up to maximum 191,411 mg $kg^{-1}$ per unit mass of ochre was removed with ochre-H. Ochre has immense potential as an agent to reduce phosphorus content in water.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.471-477
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• 2010

Although the roles of calcium in plant are widely known, little is known about on an antagonistic effect of macro elements, oxalate biosynthesis and main shape of crystal in cucumber plant organs. Seeds of cucumber (Cucumis sativus cv. Ijoeunbackdadagi) were germinated in perlite tray supplied with distilled-deionized water. Seedlings were transplanted into aerated containers with a half strength of Ross nutrient solution. Ca levels treated in media were as follows; No-Ca, $Ca(NO_3)_2$ 0.25, 1.25 and 2.5 mmol $L^{-1}$, and $Ca(NO_3)_2$ 2.5 mmol $L^{-1}$ + $CaCl_210$, 25 and 50 mmol $L^{-1}$. Ca-deficient and -excessive conditions severely reduced cucumber growth, as compared to the control, and adversely affected an accumulation of macro elements (N, P, K, and Mg). Calcium favorably induced oxalate (acid-soluble) synthesis in leaves and roots of cucumber plant, but not in stem. Acid-soluble oxalate contents in leaves proportionally increased with Ca supply levels (0.91, P<0.001), however, this pattern was not observed in stem and roots. Ca-oxalate crystal formation and compositional analysis were examined using SEM-EDS technique in cucumber leaves. The main type of crystal revealed a prismatic crystal and main components were Ca, Na and Cl.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.4
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• pp.195-200
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• 1982

Fused phosphate and slag have used as a sources of phosphate and silicate fertilizers. In order to find out effects of these fertilizers on the growth of young rice plants in nursery, relationships between dry matter production and nutrient uptake at different fertilizer application rates were investigated for two rice varieties, Milyang 23 (a Indica-Japonica hybrid) and Akibare (a Japonica). The results were summarized as followers; 1. The maximum dry matter production was obtained at 75-150 kg/10a of fused phospate and 100-200 kg/10a of slag, respectively, however, a some variations between varieties were recognized. 2. The top/root ratio of varieties around 1.0 was proper for healty see dings and this ratio was reached at application of 75 kg/10a of fused phosphate and 200 kg/10a of slag. 3. The efficiency of applied silicate of rice seedlings was higher in fused phosphate than in slag. 4. The growth of seedling was severely retarded when soil pH was increased above 7 by the application of more than 225 kg/10a of fused phospahte and 400 kg/10a of slag.

• Journal of Life Science
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• v.27 no.12
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• pp.1430-1436
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• 2017

This study assessed the effects of treatment with sap extract from onion residues postharvest and purslane on the quality and quantity of organic onions. At the bending stage, onions treated with the sap extract showed vigorous growth, with higher plant heights, more leaves, and longer sheath lengths than untreated onions. The onion yield was significantly increased when the plant was treated with extracted sap as compared with that of untreated plants (p<0.05). The bulb weight distribution of onions in the mixed onion and purslane treatment was also significantly increased (~300 g) as compared with that of the other treatment (p<0.05). Except for CaO and S, the mineral content of the onions produced from plants treated with the onion and purslane extract mixture was higher than those of onions in the other treatment. The hardness of onions produced from plants treated with the onion and purslane extract was significantly increased (8% and 20%, respectively) as compared with that of onions produced from plants treated with the onion extract only or no treatment (p<0.05). However, there was no significant difference in the sugar contents of the onions produced from extract-treated and nonextract-treated plants. Postharvest, the content of inorganic components (phosphate, calcium, sulfuric acid, and manganese) was higher in soil treated with the onion extract than in soil treated with the onion and purslane extract and non-treated soil. It can be concluded that residues left after onion harvests and purslane extract can be used as natural and environmentally friendly materials for the cultivation of organic onions.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.147-151
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• 1987

This study was conducted to evaluate the effect of the liquid waste from methane fermentation on chemical components, digestible dry matter and net energy of pasture mixtures of orchard grass, tall fescue, Kentucky bluegrass and ladino clover. The total crude proteins and crude ashes increased with the application of liquid waste, but N-free extracts decreased somewhat and it didn't affect the content of crude fat and crude fiber. Amounts of neutral detergent fiber and acid detergent fiber increased with increasing application of liquid waste and the content of cellulose in cell-wall constituents decreased, but hemicellulose increased. The digestible dry matter was produced 405 kg/10a at optimum application of 42 MT/10a liquid waste compared to NPK check plot of 233 kg/10a. The starch value and net energy lactation were 291.3 KStE and 3450 MJ-NEL respectively indicating that the optimum application of liquid waste increased their values.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.162-169
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• 1998

This study was carried out to assess the roles of soil and vegetation on the nutrient cycling in paddy ecosystem where excessive amounts of animal wastes were flowed in due to the rain. Experimental sites included one abandoned and four cropping paddy fields which were moderately terraced under a small farm village raising 90 milk cows and 35 deer under open-air condition. The watershed covered 4 ha with every 50% of uptown and fodder crops. Concentrations of $NH_4-N$ and $P_2O_5$ in waste water flowed into the abandoned paddy field, enforced by the rain of $56.4mm\;day^{-1}$, were $8.3mg\;{\ell}^{-1}$ and $1.8mg\;{\ell}^{-1}$, respectively. Total mass of rainfall inflow to abandoned field during rice growing period (1 May to 30 Sept.) was $20,900Mg\;ha^{-1}$. Total amounts of $NH_4-N$ and $P_2O_5$ contained in that inflow were estimated as 173 kg and 38 kg, respectively. Concentrations in the outflow water through one abandoned and four rice paddy fields were reduced by 92% for $NH_4-N$ and 95% for $P_2O_5$, as compared to those in the inflows. The reserved portions of nutrients in the abandoned paddy field ecosystem, which were the summation of the uptake by weed and residues in soil, were 29% of the inflow amount for $NH_4-N$ and 30% for $P_2O_5$. These results demonstrated that soil and vegetation in paddy field ecosystem reduced the excessive nutrients from the animal waste inflow to the extents that might be suitable not only for the better growth of rice plant, located at the lower paddy fields, but also for preservation of the downstream from eutrophication.