• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.252-257
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• 2004

본 연구에서는 인산염을 이용여 납으로 오염된 Clay 사격장과 인위적으로 오염시킨 자연토양의 중금속의 고정화 실험을 수행하였다. 인산염 고정화제로는 DAP (diammonium phosphate)를 사용하였다. DAP를 투입한 중금속 오염토양을 고정화 실험과 TCLP로 용출 하였을 때, 99% 정도 고정화되었다. 인산염 투여양이 증가할수록 고정화 효율은 증가하는 것으로 나타났으며, 최적 인투입량은 128 mmol as P/kg인 것으로 나타났다. DAP 투입양이 증가할수록 토양의 pH는 증가하는 것으로 나타났으며, 토양의 초기 pH 변화에 따라 고정화 효율은 크게 변하지 않은 것으로 나타났으나, pH가 높을수록 고정화 효율은 작은폭으로 증가하는 것으로 나타났다.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.3
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• pp.246-252
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• 1998

A survey was conducted to investigate the status of soils involving pH, electrical conductivity, total organic matter content, available phosphate and major exchangeable cations in the paddy soils sampled from 1,168 sites throughout the country. The content of soil chemical properties was lower on the average than the optimum levels for cropping. An average value showed pH 5.6, organic matter $25g\;kg^{-1}$, available phosphate $128mg\;kg^{-1}$, available silicate $72mg\;kg^{-1}$, and exchangeable potassium and the calcium and magnesium were 0.32, 4.0, $1.2cmol^+\;kg^{-1}$, respectively. Soil chemical properties was related with topography except soil pH. A soil pH and organic matter, available phosphate, exchangeable potassium increased with time while exchangeable calcium, magnesium available silicate decreased with time.

• The Korean Journal of Mycology
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• v.16 no.1
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• pp.41-48
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• 1988

To investigate germination characteristics of soils on Fusarium species under different soil conditions, this study was carried out to test spore germination of 4 Fusarium species. Among 102 soil samples, spore germinations of Fusarium solani f. sp. pisi, F. oxysporum f. sp. cucumerium, F. oxysporum f. sp. raphani and F. coccophilum were under 50% in 98, 85, 82 and 83 soil samples, respectively. The highest spore germination of F. solani f. sp. pisi, F. oxysporum f. sp. cucumerium and F. coccophilum was obtained in 21 soil samples of pH 5.1-6.0, whereas F. oxysporum f. sp. raphani was in 33 soil samples of pH 4.1-5.0. The highest spore germination of F. solani f. sp. pisi, F. coccophilum and F. oxysporum f. sp. cucumerium was obtained in 4 soil samples holding soil moisture content of 41-60%, while F. oxysporum f. sp. raphani was in 22 soil samples of 21-30%. F. oxysporum f. sp. raphani only showed a direct correlation(r=0.29) between spore germination and soil moisture content. On the basis of each spore germination in cultivated and non-cultivated soils, there was significant difference(p=0.01) in 4 Fusarium species. F. solani f. sp. pisi only indicated significant difference(p=0.0l) between two contrasting-soils, cultivated and non-cultivated soils. The numbers of microbial population were higher in soils suppressive to spore germination than soils conducive to spore germination.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.215-219
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• 1994

This experiment was tried for finding out some soil chemical problems when new apple trees were replanted in old orchards. Soil samples were collected from the soil horizons in the old apple orchards cultivated over 40 years and reference soils. The non-cultivated reference soils were located near the old apple orchards and each of the soils was showed as the same pedon with each of the cultivated soils. The results were as follows : Soil pH showed a tendency to decrease in low horizons of the cultivated soils whereas increase in those of the uncultivated soils. As a comparision with each chemical component, the content of exchangeable Ca or total Mn was likely to be deficient in the cultivated soils. But all components except those were not like that. Total exchangeable cations in the cultivated soils were lower than in uncultivated soils. The pH in the cultivated soils showed very high positive correlation with total exchangeable cations. From those result, it was assumed that lower pH in lower horizon which would be originated from low content of total exchangeable cations, reacts as a factor for the deterioration of old apple orchard soil.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.20-25
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• 1996

This survey was conducted to investigate the chemical properties of soils cultivated medicinal plants. The soils were collected at 254 sites(Angelica gigas : 81, Astragalus membranceus : 38, Platycodn glandiflorum : 36, Paeonia albiflora : 34, Codonopsis lanoceolata : 32, Ligusticum chuanxiong : 17. Bupleurum falcatum : 16, respectively) throughout the country by 0-15cm depth. The chemical properties of soils were pH 5.6, O.M 3.0%. Av.$P_2O_5$ : 405 mg/kg, Ex.K : $0.67cmol^+/kg$, Ex.Ca : $6.3cmol^+/kg$, Ex.mg : $1.6cmol^+/kg$. The percentage distribution of pH on the basis of soil sample numbers were much more at the 5.1-6.0 range than any other ranges, especially those of below pH 6.0 were 83-91% for Angelica gigas, Platycodn glandiflorum and Codonopsis lanoceolata. The distribution of OM and Av.$P_2O_5$ in soils were much at the 2.1-4.0% and above 500mg/kg ranges, respectively. And the content of those in soils cultivated with Platycodn glandiflorum were lower than any other medicinal plants. The distribution of exchangeable cations in soils were much at the 0.2-0.8, 2.1-4.0 and $0.5-2.0cmol^+/kg$ of Ex.K. Ca and mg. respectively, and the contents were higher in soils cultivated Astragalus membranceus. and lower in soils cultivated Platycodn glandiflorum and Codonopsis lanoceolata than any other samples.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.2
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• pp.59-65
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• 2004

Interactions of phosphorus and zinc in soils are important to determine the availability of the elements because those elements are closely related in the agricultural environment. The objective of this study was to investigate the interactions of P and Zn using desorption quantity (Q)-intensily(I) isotherms. Physically and chemically different soils, acidic Egan, acidic sandy Egeland, calcareous Glenham, and neutral Maddock, were used. The soils were enriched with different concentrations of P and Zn as $KH_2PO_4$ and $ZnSO_4$ solutions, respectively. Zinc enrichments affected availability of P in the Egan soil, which contained higher amounts of clay, organic matter, and exchangeable Fe than the other soils tested. After Zn enrichments, the pH drastically decreased in Egeland sandy soil, not changed in the calcarious Glenham soil, and slightly decreased in Egan and Maddock soil systems. The values of $Q_{max}$ and $I_0$ of phosphorus decreased with increasing Zn concentrations enriched in all soils, the changes of those values did not influence the P buffering power, |$BP_o$| values, in most soils. The influences of P treatment on Zn availability were varied. The values of Zn buffering capacity, $BC_{Zn}$, were lowest in the Egeland soil that had the lowest soil pH, amounts of clay minerals, organic matter, CEC, and exchangeable Fe, and were highest in the calcareous Glenham soil. The $BC_{Zn}$ values ranged from 202 to 4480. With P application, the changes of $BC_{Zn}$ values were more affected by the changes of soil solution Zn contents (I) than the changes of DTPA extractable Zn contents(Q). The change of Q and I values was found to be dependent upon soil properties, especially, soil pH.

• Asian Journal of Turfgrass Science
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• v.16 no.1
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• pp.11-18
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• 2002

This research was designed to know optimize soil sampling time, soil sampling depth and fertilizers according to season and soil condition in the golf course. One of the results was revealed that sampling point and depth have to be consistent for much fluctuation by sampling. Especially, Soil pH is decreased by soil depth remarkably. Top soil (0-5 cm depth) pH is higher than the sub soils (5-10 cm, 10-15 cm depth). It was confirmed that soil pH would increase when the state of soil is appropriate to H$^{+}$ ion concentration. Therefore, Soil pH modification is always not determined by lime content rather than soil conditions, i.e., Organic matter content, moisture content, and soil air content. More effective fertilizing time according to soil pH correction is the middle of october, and it's quantity is 100 g/$m^2$ silicate and 200 g/$m^2$ lime (Pel-Lime Mini) in this experiment. Recommended soil sampling method for acidity measurement is dividing by soil depth into each 5 cm respectively, rather than mixing 15 cm total soil.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.254-259
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• 1991

The present study was carried out to investigate the effect of nitrogen(urea) application on the seasonal change in pH content of Bray No.1-P, organic matter, and exchangeable cations along the grassland soil profile and further to provide the fundamental information for optimizing the rate of fertilizer application to grassland. Soil samples were taken 20cm intervals upto 100cm soil depth in spring(May 26), summer(July 27), and autumn (October 18) of 1990. The obtained results are summerized as follow 1. In spring and summer, soil pH at 0-20cm soil depth of 28kg N/10a treatment was lowered by 0.7 and 1.0 in comparison with those the same soil depth of 0 kg N/10a treatment and the tendency in pH decrease during all season at the soil depth below 20cm was in the order of summer>spring>autumn. 2. Although Bray No.1-P content at the soil depth 0-20cm of 28kg N/10a treatment was lowered by 20ppm compared to 0 kg N/10a treatment in summer, there was no great difference in its content between 0kg N/10a and 28kg N/10a treatment at all soil depth in spring and summer. In autumn, its content at soil depth below 20cm of 28kg N/10a treatment was higher than that of in summer. 3. Organic matter content at 0-20cm soil depth of 0 and 28kg N/10a treatment in autumn was slightly lowered and on the whole there was very little change in it by soil depth and nitrogen application. 4. The calcium content of 0 and 28kg N/10a treatment was also slightly lowered by increase in soil depth and Mg and K contents were below 0.4 and 0.2 me/100g during all seasons, respectively. 5. Positive correlations were shown among the $NH_4-N$ content and pH, organic matter, Ca and Mg of 0 kg N/10a treatment, however, there was negative correlation ($r=-0.534^{*}$) between $NO_3-N$ content and pH of 28kg N/10a treatment in summer.

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.21-27
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• 2018

BACKGROUND: Although 1 M $NH_4OAc$ (pH 7.0) is predominantly used as the extractant of exchangeable cations in agricultural soils, this method is unsuitable for extracting the cations in saline and calcareous soils. This study was performed to select a proper method to determine exchangeable cations in vinyl greenhouse soils. METHODS AND RESULTS: Exchangeable cations (Ca, Mg, K, Na) in saline vinyl greenhouse soils were determined after extraction with 1 M $NH_4OAc$ (pH 7.0 and 8.5) and 1 M alcoholic $NH_4Cl$ (pH 8.5). Sum of exchangeable cations of the soils extracted with 1 M $NH_4OAc$ at pH 7.0 was 1.9-2.5 times greater than soil cation exchange capaity determined at pH 7.0, even though soluble salts were pre-removed. A similar result was found when the cations were extracted with 1 M $NH_4OAc$ at pH 8.5. Those results are mostly due to the overestimation of exchangeable Ca and Mg, linked to a partial dissolution of sparingly soluble salts in $NH_4OAc$ solution. When extracted with 1 M alcoholic $NH_4Cl$ at pH 8.5, extractable Ca and Mg decreased significantly due to the lower solubility of Ca and Mg carbonates in the extractant. And the sum of exchangeable cations was very close to the corresponding exchange capacity of soils. CONCLUSION: Alcoholic $NH_4Cl$ (pH 8.5) is proposed as a reliable extractant in determination of exchangeable cations in saline vinyl greenhouse soils. And soluble salts should be removed prior to the extraction of exchangeable cations.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.49-55
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• 1999

The treatment of petroleum contaminated soil requires various physico-chemical remediation technologies which are efficient in time and can reduce the possibility of secondary contamination by themselves In this study, an innovated soil washing process was proposed to treat the diesel-contaminated soil. Micro-bubbles, which were generated by hydrogen peroxide, deserted and floated the contaminants. Soils less than #60(0.25mm) were artificially contaminated by 6,500mg TPH/kg dry soil initially. The process was examined for pH, the soil to water mixing ratio, concentration of $H_2O$$_2$, and contacting times. In the case of less than #60 soil, maximum removal efficiency(60%) was obtained at pH 12. 1.0% hydrogen peroxide, and 1 : 5 soil to water mixing ratio for 1 hour.