• Title/Summary/Keyword: soil medium

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Study on the Improvement of Soil for High Efficient and Sustainable Agriculture-II Changes of Population of Soil Microorganisms in the Fertilized Soil with Organic Materials (지속적 농업을 위한 고성능토양의 개발 연구-II 유기질비료 시용에 따른 토양미생물상의 변화)

  • Yoo, Sung-Joon;Chang, Ki-Woon;Whang, Kyung-Sook
    • Applied Biological Chemistry
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    • v.41 no.6
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    • pp.457-464
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    • 1998
  • For investigating the effect of amount of applied fertilizer with pig and chicken manures in the field, the number of soil bacteria were counted on the full strength conventional nutrient broth (NB) medium and its 100-fold dilution (DNB) medium. From the control soil samples without organic amendments, the number of bacteria on DNB medium was 5 to 10 times higher than that on NB medium. However, population density on NB medium was higher than on DNB medium from the treated soil with 60 and 120 Mg/㏊ for 3 years. Most of isolates from DNB plates did not grow on the NB plates. There were only grown on the 100-fold dilution medium, so it was called as DNB organisms. The DNB organisms were occupied as dominant group over 60% fo isolates in control soil. However, their occupation rates were rapidly decreased in the treatment soil with pig and chicken manures above 60 and 120 Mg per ha. These DNB organisms (oligotrophs) were significantly low population desities in the treatment soil with organic materials.

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Change in Chemical Compositions of Leachate and Medium Density Fiberboard from a Laboratory-scale Simulated Landfill

  • Lee, Min;Prewitt, Lynn;Mun, Sung Phil
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.2
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    • pp.231-240
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    • 2016
  • The change in chemical compositions of leachate and medium density fiberboard (MDF) from a laboratory-scale simulated landfill which constructed in a plastic container containing alternating layers of soil and MDF was investigated to evaluate decomposing of MDF in soil. Four treatments were conducted: 1) MDF in soil, 2) MDF only, 3) cured UF resin in soil, and 4) soil only. Molecular weight (MW) distribution of compounds in leachate from soil only treatment did not change over time. In UF resin in soil treatment, the MW distribution shifted to a lower MW distribution over time, while the peak shifted to the left indicated changing to higher MW distribution in leachate from treatment 1 and 2 contained MDF. Higher percent nitrogen in leachate was observed in MDF containing treatments due to the UF resin in the MDF. The percent carbon slightly increased in MDF only while that greatly decreased in MDF in soil treatment maybe due to bacterial activity. The percent of extractable materials from the MDF decreased greatly on day 35 compare to day 0, and subsequently did not change much on day 77. In contrast, percent holocellulose and lignin did not change much over time. No structural change of the wood fiber in MDF occurs during the study. Water-soluble materials from MDF in soil contributed the change in chemical composition of leachate.

The effect of root zone environment on the growth of shoot and root of tobacco plant (연초의 근권환경이 뿌리와 지상부의 생육에 미치는 영향)

  • 이부경
    • Journal of the Korean Society of Tobacco Science
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    • v.11 no.2
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    • pp.197-202
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    • 1989
  • This experiment was conducted to investigate the effect of growth medium in pots composed of upland soil(S), rice straw manure(M), carbonated rice hull(CRH), and their mixture on growth of tobacco cv. NC 82. The growth of shoot and root was vigorous in order of medium S+M+CRH>M>CRH>S. In M+S medium, root growth in the part of manure was superior to upland soil. But root growth of upland soil part in M+S plot was more vigorous than that in upland soil only. It is possibly due to be influenced by manure in M+S plot. Total length and weight of root, number of roots, and especially for development of adventitious root were closely related to shoot growth. Roots grown in upland soil part was brownish gray in color, while the roots in manure part was milky white. The milky white colored roots had longer life than others. It was concluded that root zone environments derived from several media in pots closely related to shoot growth and disease tolerance of tobacco plant.

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Effect of Biofilm Formation on Soil Sorbed Naphthalene Degradation (Biofilm 생성이 토양흡착 나프탈렌 분해에 미치는 영향)

  • Li, Guang-Chun;Chung, Seon-Yong;Park, Jeong-Hun
    • Journal of Soil and Groundwater Environment
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    • v.14 no.6
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    • pp.45-52
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    • 2009
  • Naphthalene-degrading bacteria Pseudomonas aeruginosa CZ6 isolated from contaminated soil can adhere to crystal naphthalene and produce extracellular polymeric substance. LB, YM and MSM medium were used as culture mediums to investigate the formation of biofilm. Biofilm was developed the most in LB medium by Pseudomonas aeruginosa CZ6. In the culture, strain CZ6 growth was rarely affected by naphthalene concentration. Optimal culture condition was $30^{\circ}C$ and pH 7 at 0.10% substrate and 150 rpm shaking. The effect of culture medium on naphthalene degradation in the two soil slurry system was evaluated. The initial degradation rate of naphthalene was highest in the MSM medium of soil slurry. However, the sorbed naphthalene was rapidly degraded at the LB medium when naphthalene availability in liquid was limited. The results of this study suggest that biofilm formation and extracellular polymeric substance production increased bioavailability of soil sorbed naphthalene.

Environmental Assessments of Leachate from Medium Density Fiberboard in a Simulated Landfill

  • Lee, Min;Prewitt, Lynn;Mun, Sung Phil
    • Journal of the Korean Wood Science and Technology
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    • v.43 no.5
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    • pp.548-557
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    • 2015
  • This study investigated environmental assessments of leachate containing formaldehyde from medium density fiberboard (MDF) disposed in laboratory-scale simulated landfills. Environmental impact assessment of leachate was conducted by measuring formaldehyde, toxicity, biochemical oxygen demand (BOD), chemical oxygen demand (COD), bacterial enumeration, and pH. Amount of formaldehyde in leachate from MDF in soil decreased to the level of soil only treatment by 28 days, and toxicity decreased as the amount of formaldehyde decreased. BOD and COD levels in leachate from the treatments containing MDF exceeded permissible discharge levels of BOD or COD throughout the experimental period. The pH levels of all treatment were within permissible discharge range except on day 0. Fewer bacteria were observed in leachate from MDF in soil treatment than other treatments (MDF only, cured UF resin in soil, and soil only). Consequently, the leachate from disposal of MDF in soil detrimentally affect on environment. However, soil buffered formaldehyde leaching and pH on leachate in this study. Waste MDF may be required the pre-water soaking treatment for leaching formaldehyde to reclaim on land.

3-D Axisymmetric Fluid-Structure-Soil Interaction Analysis Using Mixed-Fluid-Element and Infinite-Element (혼합형 유체요소와 무한요소를 이용한 3차원 축대칭 유체-구조물-지반 상호작용해석)

  • 김재민;장수혁;윤정방
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1999.10a
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    • pp.257-266
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    • 1999
  • This paper presents a method of seismic analysis for a cylindrical liquid storage structure on/in horizontally layered half.space considering the effects of the interior fluid and exterior soil medium in the frequency domain. To capture the essence of fluid-structure-soil interaction effects effectively, a mixed finite element with two-field (u, p) approximation is employed to model the compressive inviscid fluid, while the structure and soil medium are presented by the 3-D axisymmetric finite elements and dynamic infinite elements. The present FE-based method can be applied to the system with complex geometry of fluid region as well as with inhomogeneous near-field soil medium, since it can directly model both the fluid and the soil. For the purpose of verification, dominant peak frequencies in transfer functions for horizontal motions of cylindrical fluid storage tanks with rigid massless foundation on a homogeneous viscoelastic half.space are compared with those by two different added mass approaches for the fluid motion. The comparison indicates that the Present FE-based methodology gives accurate solution for the fluid-structure-soil interaction problem. Finally, as a demonstration of versatility of the present study, a seismic analysis for a real-scale LNG storage tank embedded in layered half.space is carried out, and its member forces along the height of the structure are compared with those by an added mass approach developed by the present writers.

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Bacterial Community Variations in Hot Pepper-Sown Soil Using FAME Analysis as an Indicator of Soil Quality

  • Kim, Jong-Shik;Weon, Hang-Yeon;Kwon, Soon-Wo;Ryu, Jin-Chang
    • Journal of Microbiology and Biotechnology
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    • v.13 no.2
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    • pp.251-255
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    • 2003
  • The bacterial compositions of seven hot-pepper sown soil were compared in this study. From the 624 isolates, 95 species and 49 genera were identified by fatty acid methyl ester analysis (FAME). The FAME results of seven soil showed two distinct clusters for aerobic and Gram-negative bacteria in the high productivity and monoculture soil samples. While Arthrobacter ($17\%$), Kocuria ($11\%$), Pseudomonas ($8\%$), and Bacillus ($8\%$) were predominant among bacteria which were cultured on heterotrophic (YG) agar medium, Pseudomonas ($56\%$), Stenotrophomonas ($16\%$), and Burkholderia ($8\%$) were predominant on crystal violet agar medium. Shannon Weaver indices (H) indicated that colonies obtained from heterotrophic agar medium (3.1) were found to be more diverse than those obtained from the crystal violet media (1.9). The results suggest that FAME analysis may be a potential indicator for of soil quality.

Growth of Dendranthema zawadskii in Chloride-containing De-icing Salt Areas Upon Treatment With Soil Amendments (제설제 피해지에서 토양개량제 처리에 따른 구절초의 생육특성 비교)

  • Ju, Jin-Hee;Yang, Ji;Park, Sun-Young;Yoon, Yong-Han
    • Journal of Environmental Science International
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    • v.30 no.3
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    • pp.235-243
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    • 2021
  • This study was conducted to investigate the growth of Dendranthema zawadskii in damaged soils when they are treated with improvement agents. The treatments consisted of a control (unamended field soil) and the application of a loess ball of 1 cm to the field soil. According to the degree of damage the de-icing agent had caused, the soils were divided into 3 areas (based on the yellowing of Pinus densiflora for. multicaulis in soil surveys): H (high saline), M (medium saline), and L (low saline). A total of six treatments were performed: D. zawadskiia plant without soil amendment (H; high saline soil, M; medium saline soil, L; low saline soil), and a D. zawadskiia plant with loess ball on the soil surface (H.L; high saline soil with loess ball, M.L; medium saline soil with loess ball, L.L; low saline soil with loess ball). The results showed that D. zawadskiia growth went from highest to lowest in the order: M.L > L.L > M > L > H.L > H. Plant growth results showed that soils treated with soil amendments (loess ball) were better for D. zawadskii growth than untreated soils.

Formaldehyde Release from Medium Density Fiberboard in Simulated Landfills for Recycling

  • Lee, Min;Prewitt, Lynn;Mun, Sung Phil
    • Journal of the Korean Wood Science and Technology
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    • v.42 no.5
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    • pp.597-604
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    • 2014
  • Laboratory-scale landfills (simulated landfills) were designed to determine the formaldehyde released into air and leachate from medium density fiberboard (MDF). Simulated landfills were constructed using cylindrical plastic containers containing alternating layers of soil and MDF for a total of five layers. The highest concentration of formaldehyde was found in the air and leachate from the MDF only treatment compared to treatments containing MDF and soil. At the end of the study (28 days), formaldehyde concentrations in air and leachate from treatments containing MDF and soil decreased by 70 percent and 99 percent, respectively, while the treatment containing MDF only still released formaldehyde into the air and leachate. Therefore, waste MDF after storing 4 weeks in water may be recycled as compost or mulch based on formaldehyde leaching. Also, these data indicate soil restricts formaldehyde release into air and leachate and provides new information about the fate of wood-based composite waste containing UF resin disposed in landfills.

Dynamic Analysis of Building Structures for Subway Transit Loading (지하철운행 하중에 대한 인접 구조물의 진동해석)

  • 윤정방;이동근;정진상;김두기
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1995.10a
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    • pp.266-273
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    • 1995
  • An efficient dynamic analysis method is developed f3r building structures subjected to ground home loadings. The soil medium is modeled using the finite elements and infinite elements. Then, the dynamic stiffness of the soil medium is calculated at the interfacial nodes between the soil and the building foundation. The equivalent subway loading at the interfacial nodes are obtained from the wave propagation analysis of the subway loading through the soil medium. The dynamic response of the building Is computed using the mode superposition method equipped with gauss-seidel iteration technique. The analysis is carried out by the frequency domain and the time domain methods.

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