• Korean Journal of Environmental Agriculture
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• v.23 no.2
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• pp.104-110
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• 2004

Although silicon (Si) has been Down to be an essential element fer rice growth, the optimum soil level of Si for upland crops remains unestablished. This study was conducted to estimate the availability of Si fertilizer in upland soils, and also effect of the Si fertilizer on soil pH was examined. Different application rates of Si fertilizer were tested using faur soils of different available Si levels and pHs in a series of laboratory incubation study. The treatments included Si fertilizer levels of 100, 200, and 300 kg/10a. Also to examine the effects of compost and lime on the availability of Si fertilizer in upland soil, treatment of silicate fertilizer 200 kg/10a + compost 1,000 kg/10a and lime alone treatment were included. Changes of Si availability in the soils during the incubation period were measured by 1 N NaOAc extraction procedure. Availability of Si fertilizer was different among the tested soils, and about $9.1{\sim}19.2%$ of the applied Si fertilizer was extracted after 60 days laboratory incubation. Application rate could not influence the availability of Si fertilizer. Application of compost with Si fertilizer could not increase Si availability in upland soils, but lime treatment could increase Si availability. Soil pH increased by application of Si fertilizer, but the effect of Si fertilizer on soil pH was minimal. When Si fertilizer is applied on the purpose of Si nutrition in acid upland soils, lime treatment should be coupled with the Si fertilizer for remediation of soil acidity.

• Journal of Soil and Groundwater Environment
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• v.11 no.1
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• pp.23-36
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• 2006

Experimental leaching of tailings was performed as a function of times (1, 2, 4, 7, 14, 21 and 30 days) in the laboratory using reaction solutions equilibrated to three different pH set-points (pHs 1,3 and 5). The initial pHs of 5 and 3 stabilized at either 4.6-6.1 or 2.8-3.5 in 2 days and decrease gradually with time afterwards. The results of the leaching tests indicate that the significant increase in the sulfate concentrations and in acidity after 7 days of leaching results from the oxidation of sulfide minerals. There were no significant variations in the extractable Pb found in the leach solutions of pH 5 and 3 within the reaction time (1-30 days), while Zn, Cd and Cu concentrations tend to significantly increase with time. In tailings leaching at an initial pH=1, two trends were observed: i) The 'Zn-type' (Zn, Cd and Cu), with increasing concentrations between days 1 and 30, corresponding to the expected trend when continuous dissolution is the dominant process, ii) the 'Pb-type' (Pb), with decreasing concentrations over time, suggesting rapid dissolution of a Pb source followed by the precipitation of 'anglesite' in relation to the large increase in dissolved sulfates. The high sulfate concentrations were coupled with high concentrations of released Fe, Zn and Cd. Release of Zn and Cd and acidity from these leaching experiments can potentially pose adverse impact to surface and groundwater qualities in the surrounding environment. The kinetic problems could be the important factor which leads to increasing concentrations of trace metals in the runoff water.

• Journal of Soil and Groundwater Environment
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• v.24 no.2
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• pp.1-7
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• 2019

The feasibility of using hydrated lime ($Ca(OH)_2$) was assessed in reducing soil loss in sloped land under field condition. During 6-month monitoring from May to October, amendment of hydrated lime (3%, w/w) to a test plot decreased soil loss by 76% as compared to the unamended plot. However, the growth of natural vegetation was hampered by hydrated lime addition due to pH increase. Hydrated lime can be used as an effective agent to prevent soil loss in sloped land, but additional treatments are needed to preserve vegetation growth, especially in crop fields.

• Journal of Ginseng Research
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• v.39 no.1
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• pp.81-88
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• 2015

Background: In Changbai Mountains, Panax ginseng (ginseng) was cultivated in a mixture of the humus and albic horizons of albic luvisol in a raised garden with plastic shade. This study aimed to evaluate the impact of ginseng planting on soil characteristics. Methods: The mixed-bed soils were seasonally collected at intervals of 0-5 cm, 5-10 cm, and 10-15 cm for different-aged ginsengs. Soil physico-chemical characteristics were studied using general methods. Aluminum was extracted from the soil solids with $NH_4Cl $(exchangeable Al) and Na-pyrophosphate (organic Al) and was measured with an atomic absorption spectrophotometer. Results: A remarkable decrease in the pH, concentrations of exchangeable calcium, $NH_4^+$, total organic carbon (TOC), and organic Al, as well as a pronounced increase in the bulk density were observed in the different-aged ginseng soils from one spring to the next. The decrease in pH in the ginseng soils was positively correlated with the $NH_4^+$ (r=0.463, p<0.01), exchangeable calcium (r=0.325, p<0.01) and TOC (r= 0.292, p < 0.05) concentrations. The $NO_3^-$ showed remarkable surface accumulation (0-5 cm) in the summer and even more in the autumn but declined considerably the next spring. The exchangeable Al fluctuated from $0.10mg\;g^{-1}$ to $0.50mg\;g^{-1}$ for dry soils, which was positively correlated with the $NO_3^-$ (r=0.401, p < 0.01) and negatively correlated with the TOC (r=-0.329, p < 0.05). The Al saturation varied from 10% to 41% and was higher in the summer and autumn, especially in the 0-5 cmand 5-10 cm layers. Conclusion: Taken together, our study revealed a seasonal shift in soil characteristics in ginseng beds with plastic shade.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.2
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• pp.128-133
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• 1994

This study was carried out to get agronomic information about the tobacco culture in paddy soil where incidence of grey tobacco leaves used to appearly uptake of iron, manganese and chlorine due to soil acidity and high water level. Application of lime to paddy soil(pH5.4-5.6) reduced content of iron, manganese known as proceeding materials giving rise to variegated grey tobacco after curing, compared with non-treatment. Grey leaves were found mainly at lower and middle stalk positions, and incidence of grey tobacco was lowered by application of lime in the well drained field but was not affected by level of fertilizer application. Amendment of soil acidity by lime tended to decrease chlorine and manganese content in leaves. Nicotine and mangenese content of leaves were lowered by reduction of one-quarter fertilizer level. In case of lime treatment, increase of yield reached to 4-6% comparing with those of non-treatment but price per kg was not affected. Reduction of N fertilizer level to three-quarters had the equal yield but high quality of leaf comparing with standard fertilization in paddy field.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.1
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• pp.38-49
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• 1985

The water soluble organic fractions (WSOF) from an agricultural soil (W), a soil treated with sludge for 6 years ($WS_6$), a sludge-soil mixture incubated for one week ($WS_1$), and sewage sludge (SS) were extracted, purified, and characterized by elemental analysis, functional group determinations, infrared, UV-visible, and proton nuclear magnetic resonance spectrosocpy. The SS was characterized by higher organic H, N, and P contents, a higher H/C ratio, and a lower C/N ratio than W. Total acidity carboxyl and phenolic hydroxyl group contents were generally highest in SS, intermediate in $WS_6$ and $WS_1$, and lowest in W. Overall aromatic character and aromatic carboxyl group contents were highest in W, and lowest in SS. Aliphatic proton, aliphatic carboxyl, and phenolic hydroxyl group contents were highest in SS, and lowest in W. Protein decomposition products were the pronounced components in SS, and decreased in concentration as the sludge component in the mixtures decreased. The $^1H$-NMR spectra suggested that the SS-protons were bound to a wider range of functional groups than W-protons. Structural complexities around the aromatic protons followed the following order: SS>$WS_1$>$WS_6$>W.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.5
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• pp.614-620
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• 2016

Mine soils are usually unfavorable for plant growth due to their acidic condition and low contents of organic matter and nutrients. To investigate the effect of organic material and lime on nitrogen processes in an acidic metal mine soil, we conducted an incubation experiment with treating livestock manure compost, dolomite, and oyster shell and measured soil pH, dehydrogenase activity, and concentration of soil inorganic N ($NH_4{^+}$ and $NO_3{^-}$). Compost increased not only soil inorganic N concentration, but also soil pH from 4.4 to 4.8 and dehydrogenase activity from 2.4 to $3.9{\mu}g\;TPF\;g^{-1}day^{-1}$. Applying lime with compost significantly (P<0.05) increased soil pH (5.9-6.4) and dehydrogenase activity ($4.3-7.0{\mu}g\;TPF\;g^{-1}day^{-1}$) compared with applying only compost. Here, the variation in dehydrogenase activity was significantly (P<0.05) correlated with that in soil pH. Soil inorganic N decreased with time by 14 days after treatment (DAT) due to N immobilization, but increased with time after 14 DAT. At 28 DAT, soil inorganic N was significantly (P<0.05) higher in the lime treatments than the only compost treatment. Especially the enhanced dehydrogenase activity in the lime treatments would increase soil inorganic N due to the favored mineralization of organic matter. Although compost and lime increased soil microbial biomass and enzyme activity, ammonia oxidation still proceeded slowly. We concluded that compost and lime in acidic mine soils could increase soil microbial activity and inorganic N concentration, but considerable ammonium could remain for a relatively long time.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.354-358
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• 2014

Field study was conducted to evaluate the agronomic effectiveness of sulphur-bentonite fertilizer. Soil pH was slightly lower tendency to the increase of sulphur-bentonite fertilization, but did not indicate a sharp decline in soil pH. The T-N contents in the $6kg/1000m^2$ plot was higher to 700 mg/kg and the organic matter content was 1.29% in the $3kg/1000m^2$ plot. The content of available-P was also increased to 289 mg/kg in the $6kg/1000m^2$ plot. The growth characteristics of the young radish (Raphanus sativus L.) has significantly more in $3kg/1000m^2$ plot on upper part, and more on under part in $6kg/1000m^2$ plot. Therefore, it is concluded that the application of sulphur-bentonite fertilizer was thought to be effective for the chemical characteristics of soil and crop growth enhancement.

• The Korean Journal of Ecology
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• v.19 no.3
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• pp.201-207
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• 1996

Selection of Al tolerant woody plants, and possibility of reforestation with the Al tolerant plants in soil conditions with different Al content, topography and slope exposures were studied on the slopes around Yeocheon Industrial Complex. Root growth in length of plants grown in 1/2 Steinberg solution decreased with increased Al concentrations of the solution. Relative root length showed that Paulownia coreana, Celtis sinensis and Firmiana simplex were sensitive to $500\muM$ Al, Pinus koraiensis, Alnus japonica and Ligustrum japonicum were intermediate, and Pinus rigida, P. densiflora and P. thunbergii were tolerant to $1, 000\muM$ Al. Coniferous plants appeared to be more tolerant to Al than deciduous ones. Soil pH was 4.2 and Al content was 509 ppm in average around the Yeocheon industrial complex. Al content and soil acidity were more deteriorated on the foothill and slope facing to the pollution source from the industrial complex than on the ridge and opposite slope.

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1447-1455
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• 2011

The purpose of this study was to analyze physicochmical characteristics of oil within planting base of Incheon coastal reclamation cities where 10 years have passed since reclamation, and to provide basic data to promote growth and development of plants by conducting evaluation based on the planting degree standard. Study targets were Cheongra, Sondo, and Yeongjong districts within Incheon Free Economic Zone, the coastal reclamation city. The analysis results of average soil characteristics of 3 districts. Soil acidity(pH) was shown in orders of Cheongra district(8.85) > Songdo district(8.70) > Yeongjong district(7.97) and electric conductivity(EC) was shown in orders of Cheongra district(4.80 dS/m) > Songdo district(1.30dS/m) > and Yeongjong district(0.07 dS/m). Organic matter content(OMC) was shown in orders of Cheongra district(5.72%) > Songdo district(2.60%) > Yeongjong district(0.59%) and available phosphate was shown in orders of Cheongra district(70.70 mg/kg) > Songdo district(23.07 mg/kg) > Yeongjong district(2.49 mg/kg). $K^+$ was shown in orders of Songdo district(0.84 cmol/kg) > Cheongra district(0.74 cmol/kg) > Yeongjong district(0.22 cmol/kg), $Ca^{++}$ was shown in orders of Cheongra district(22.08 cmol/kg) > Songdo district(9.87 cmol/kg) > Yeongjong district(4.04 cmol/kg), and $Mg^{++}$ was shown in orders of Cheongra district(1.98 cmol/kg) > Songdo district(1.22 cmol/kg) > Yeongjong district(1.12 cmol/kg). Planting base level of coastal reclaimed land can be applied with above intermediate level, soil acidity and available phosphate were all more than intermediate in 3 districts, and electric conductivity was low level in Cheongra district and more than intermediate level in Songdo and Yeongjong districts. Organic matters content was more than intermediate level in Cheongra district and low level in Songdo and Yeongjong district. $K^+$ among exchangeable ions was intermediate level in Cheongra and Songdo districut and low in Yeongjong district. $Ca^{++}$ and $Mg^{++}$ both were more than imtermidiate levels in 3 districts.