• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.500-512
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• 2009

This study was carried out to evaluate the effect of temperature on soil microbial biomass, enzyme activities, and PLFA content in the volcanic(VAS) and the non-volcanic ash soil(NVAS). The soils were treated with organic materials such as organic fertilizer pelleted(OFPL), organic fertilizer powdered(OFPD), pig manure compost(PMC), and food waste compost(FWC). Two grams of organic materials were well mixed with 30g of dried volcanic and non-volcanic ash soil(< 2 mm) with 50% of soil moisture content. And the soils were incubated at 10, 20, $30^{\circ}C$ in incubator. Soils were analysed on the incubation times as followed; soil pH, total nitrogen, organic matter(at 75, 150, 270 days), microbial biomass C and PLFA (at 75, 270 days), microbial biomass N and soil enzyme(at 150, 270 days). pH values of soils treated with PMC and FWC had no changes on soil type, and incubation temperature. However, the pH was increased with temperature in the soils treated with OFPL. The changes in NVAS was higher than in VAS. Soil microbial biomass C content were high in the condition of high temperature and organic fertilizers treatment in VAS. But the contents were gradually decreased with incubation period in both NVAS and VAS. Soil microbial biomass N was high in NVAS treated with organic fertilizers and in VBS treated with PMC and FWC. PLFA content was higher in NVBS than in VBS at 75 days but showed high in VBS at 270 days. Urease activity of NVBS treated with OFPL showed $10^{\circ}C$ (75.0)> $20^{\circ}C$ (16.3)>$30^{\circ}C$ ($4.6ug\;NH{_4-}N\;g^{-1}\;2h^{-1}$) at 150 days. It were decreased gradually high temperature and time passes. And it showed high at $10^{\circ}C$ in VBS. Glucosidase activity was higher in NVBS than in VBS. Correlation coefficient of between soil microbial biomass C and microbial activity indicators showed that PLFA was high significantly at $r^2=0.91$ in NVBS and ${\beta}-glucosidase$ was $r^2=0.83$ in VBS. Soil microbial activities showed differences in the relative sensitivities of soil type and soil temperature.

• Journal of Soil and Groundwater Environment
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• v.6 no.2
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• pp.31-38
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• 2001

An illegal landfill In Korea was evaluated in a view of environmental quality to figure out reusing the area. The sampling spots were selected at a point in the landfill and three points in it's around area(two points in a paddy soils and one in a farm field). The eleven pollutants regulated in the Korean Soil Environmental Preservation Act (KSEPA) were analysed from the soil sample with the method of the KSEPA. As the results of the analysis the level of concentration with most samples indicated the requirement of the KSEPA. The concentration of soil samples met the standard: however, some pollutants in the ground water and leachate showed higher concentration than that of the requirement. Therefore, we must consider the treatments of the pollutants in the ground water and leachate when designing this landfill area for reusing.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.415-418
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• 2006

회동저수지를 중심으로 수영강 일대 하상퇴적물에 대한 PAHs(Polycyclic Aromatic Hydrocarbons) 오염특성 연구가 진행되었다. 하상퇴적물의 화학분석결과, 16 EPA PAHs 중 naphthalene 등 총 15개 성분이 검출되었으며, benzo(a)anthracene과 chrysene의 검출빈도가 가장 높고, 총 PAHs는 최대 7,116 ppb가 검출되었다. 한편 퇴적물 내 PAHs의 심도별 함량 변화는, 대체로 하부 시료에 비해 상부 시료에 PAHs 함량이 높게 나타나며, 특히 상부의 점토질 토양과 하부의 현지 토양이 함께 산출되는 시료의 경우, 하부 현지 토양에서의 PAHs 함량에 비해 상부 점토질 토양에서의 PAHs 함량이 높으며, 이는 PAHs가 수영강 으로부터 유입되어 주로 상부 점토질 퇴적물에 축적된 결과로 판단된다. PAHs의 기원은 전반적으로 수영강 상류지역에서는 연소 기원을 보이며, 수영강 하류에서는 교량 및 도심지역에서의 차량통행과 관련이 있는 석유류의 특징을 나타내며, 회동저수지의 경우 석유류와 연소 기원의 특징을 복합적으로 보여주고 있다.

• Economic and Environmental Geology
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• v.55 no.2
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• pp.209-217
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• 2022

The purpose of this study was to confirm the dissolution of arsenic from the stabilized soil around abandoned coal mines by cultivation activities. Experimental soils were collected from the agricultural field around Okdong and Buguk coal mines, and the concentration of arsenic in the soil and the geochemical mobility were confirmed. The average arsenic concentration was 20 mg/kg. The soil with relatively high geochemical mobility of arsenic in the soil was used in the batch and column experiment. The limestone was mixed with soil for soil stabilization, and the mixing ratio was 3% of limestone, based on the soil weight. The phosphoric acid fertilizer (NH₄H₂PO₄) was added to the soil to simulate a cultivation condition according to the Rural Development Administration's rules. Comparative soil without mixing limestone was prepared and used as a control group. The arsenic extraction from soil was increased following the fertilizer mixing amount and it shows a positive relationship. The concentration of phosphate in the supernatant was relatively low under the condition of mixing limestone, which is determined to be result of binding precipitation of phosphate ions and calcium ions dissolved in limestone. Columns were set to mix phosphoric acid fertilizers and limestone corresponding to cultivation and stabilization conditions, and then the column test was conducted. The variations of arsenic extraction from the soil indicated that the stabilization was effectible until 10 P.V.; however, the stabilization effect of limestone decreased with time. Moreover, the geochemical mobility of arsenic has transformed by increasing the mobile fractions in soil compared to initial soil. Therefore, based on the arsenic extraction results, the cultivation activities using phosphoric fertilizer could induce a decrease in the stabilization effect.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1108-1113
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• 2012

The changes of soil organic carbon (SOC) content in paddy soils (sandy loam) were assessed from data of the 59 years fertilization plots in which the continuous rice cropping experiment started in 1954. The treatments were no fertilization(no fert.), NPK fertilization (N, NPK), NPK plus rice straw compost (NPK+C), and NPK plus rice straw compost, silicate fertilizer and lime (NPK+CLS). After 41 years, SOC content in NPK+C and NPK+CLS treatment in surface soils (0~15 cm) reached at the highest, followed by maintaining a plateau level for 8 years. After 51 years, they showed a tendency to decrease. Peak concentrations of soil organic carbon were $20.1g\;kg^{-1}$ in NPK+CLS, $19.1g\;kg^{-1}$ in NPK+C, $13.3g\;kg^{-1}$ in NPK, $11.9g\;kg^{-1}$ in N, and $11.6g\;kg^{-1}$ in control. Dissolved organic carbon(DOC) contents in surface soil solution were about 2.3 times higher in NPK+C than that in NPK+CLS. Therefore, SOC in subsurface soil(15~30 cm) was greater in NPK+C than the other treatments. These results indicate that continuous application of rice straw compost and silicate fertilizer affected significantly on the level of SOC in surface soils, subsurface soils, and soil solutions. Thus, the combined applications of NPK fertilizers with organic compost and silicate as a soil amendment are recommended as the best fertilization practice for soil carbon accumulation, environment conservation, and enhancement of soil fertility status in the continuous rice cropping system.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.3-8
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• 2002

본 연구는 트랙터 부착형 자동 토양경도 측정 시스템의 개발에 관한 연구로서, 우리나라 토양조건이나 작업형태에 맞는 에너지 절감형 트랙터 로타리날을 개발하기 위한 전단계 연구로서, 기존에 개발된 로타리날과 개량, 보완되어 개발될 로타리날의 성능을 비교 분석하기 위하여 수동 토양경도 측정기의 부정확성을 개량하여 측정의 정확성을 통한 동일 실험조건에서의 실험을 실시하고자 자동으로 작동되며 토양경도측정을 할 수 있는 트랙터 부착형 자동 토양경도 측정 시스템을 개발하는데 목적이 있으며, 그 구체적인 연구 결과는 다음과 같다. (1) 시스템은 토양경도 측정부, 측정장치 구동부, 그리고 트랙터와의 연결부로 구성되었다. (2) 시스템 작동에 필요한 전원공급을 트랙터 배터리에서 공급하였다. (3) 토양경도 측정시 토양속에 돌이나 이물질 층이 형성되어 있는 경우에 콘 페니트로메타가 관입하다가 큰 관입저항 때문에 관입저항 한계설정치까지 가기전 더이상 관입을 못하는 경우가 발생하였다. (5) 성능실험시 관입심이 깊을수록 시험포장 전체에서 대체적으로 토양경도가 높은 것으로 나타났으며, 토양속의 돌이나 이물질 등에의해 경도가 급격히 증가하는 부분이 있는 것으로 사료된다. 이상의 결과에서 살펴보면 본 시스템은 토양경도 측정에 적절하다고 사료된다.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.4
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• pp.287-292
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• 1990

A study has been conducted since 1954 to elucidate the effects of longterm application of ammonium sulfate (AS), urea, compost, and calcium silicate(CS) fertilizers on major soil nutrients and rice yields in wetland soil. The soil pH in the AS plot become lower than that in the urea plot but had little influence on rice yield. Continuous application of AS and urea with compost and CS raised the soil pH compared with single applications of AS or urea. Soil organic matter content increased yearly in plot with no fertilizer and in those with AS and urea, and increased considerably in plots with compost and CS. Application of compost and CS promoted rice top growth as well as root growth, resulting in increased dry matter. Soil contents of N, $P_2O_5$, Ca, Mg, and $SiO_2$ in the NPK with composts plot increased considerably compared with the NPK plot; however. the exchangeable K content was rather low. Rice growth increased with compost application. which enhanced K uptake, and the coarse texture promoted K leaching. With compost and CS addition, con tents of exchangeable Ca and Mg in the AS plot decreased considerably more than in the urea plot. Probably this was the result of higher Ca and Mg precipitation by sulfate in the AS plot. The re are no significant differences in rice yield between AS and urea plots. With compost and CS treatments, rice yields increased in the AS plot compared with the urea plot. The increase in yield is considered to be the effect of S. which is a constituent of AS.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.177-180
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• 2004

계면활성제를 이용한 오염된 토양을 복원하는데 있어 계면활성제의 회수하는 방법의 하나로 한외여과 방식의 타당성을 검토하였다. 계면활성제의 종류, 전해질과 첨가제로서의 알코올 및 휴믹 물질과 점토질에 의한 상대 플럭스의 변화와 투과액의 계면활성제의 농도 변화를 살펴보았다. 계면활성제의 경우 임계미셀농도 낮을수록 투과액의 농도가 낮았으며, 기타 첨가물은 농도에 비례하여 상대 플럭스가 감소하는 경향을 보였다.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.328-335
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• 1996

Using literature data on back titration curves of some typical Korean soils and minerals we calculated the distribution functions of aparent surface dissociation constants for these materials using site heterogeneity approach. The studied materials exhibited broad range of apparent surface dissociation constants. The dominant surface sites for all samples appeared to be very weakly acidic. However, the relative amounts of surface sites differed among particular materials.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.151-163
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• 2022

This study was conducted to promote organic fertilizer(s) that sustain soil productivity for corn production and protect the environment as required by the Act on the promotion of eco-friendly agriculture. It was conducted at the research station of the Organic Agriculture Division of the National Institute of Agricultural. The treatments consisted of Compost (Com), Bokashi as fermented organic fertilizer (FOF), and mixed expeller pressed cake (PC). They were applied at 174 kg N /ha to field corn, together with a 'no fertilizer' check in Randomized Complete Block Design. At eight weeks after transplanting (WAT) corn, compost increased soil carbon (C) and nitrogen (N) to 7.48 and 0.76 g/kg respectively, while other fertilizers maintained the initial levels (before treatment application). At corn harvest (13 WAT), soil chemical properties (total C, total N, pH, electrical conductivity, P₂O₅, Ca, K, and Mg) were similar among all organic fertilizer treatments. For soil respiration, FOF increased soil CO₂ respiration by 31-76% above other fertilizer treatments. However, there were no prominent changes in the trends of CH₄ fluxes following the two mechanical weeding operations. Fermented organic fertilizer affected N₂O emissions between 87-96% lower than other fertilizer treatments. Compared to the initial microbial densities, FOF increased fungi and actinomycete colony foming unit by 25 and 16% at harvest. Therefore, the additional potential of improving soil biological fertility and local availability of raw materials make FOF a better option to sustain soil productivity while protecting the environment.