• 제목/요약/키워드: soils

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Soil Classification of Anthropogenic Soils in a Remodeled Area Using Soil Taxonomy and World Reference Base for Soil Resources

  • Lee, Seung-Been;Chun, Hyen-Chung;Cho, Hyun-Jun;Hyun, Byung-Keun;Song, Kwan-Cheol;Zhang, Yong-Seon;Sonn, Yeon-Kyu;Park, Chan-Won
    • 한국토양비료학회지
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    • 제46권6호
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    • pp.536-541
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    • 2013
  • In Soil Taxonomy system, anthropogenic soils are still classified as Entisols since the International Classification Committee for Anthropogenic Soils is in the process of classifying anthropogenic soils as new orders. In reality, it is difficult to characterize anthropogenic soils because Soil Taxonomy (ST) system does not distinguish between natural and anthropogenic Entisols. On the other hand, World Reference Base for soil resources (WRB) considers human impacts on soils and contains an independent category of anthropogenic soils, which makes easier to understand anthropogenic soil characteristics than Soil Taxonomy system. A remodeled paddy field (Gasan) was selected to classify by ST and WRB. Soil samples were taken to analyze chemical and physical properties. Based on the results of the analyses, the ST system classified Gasan as coarse loamy, mixed, mesic, Aquic Udorthents while the WRB did as Stagnic Urbic Technosols (Oxyaquic, Arenic). As a conclusion, the WRB classification information of the anthropogenic provides more detail characteristics of the anthropogenic soils.

폴리에스테르 직물의 발수발유 가공처리가 유성오구의 부착 및 제거에 미치는 영향 (The Effects of Water-and Oil-Repellent Finishes on the Deposition and Removal of Oily Soils from Polyester Fabrics)

  • 이정숙
    • 대한가정학회지
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    • 제35권4호
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    • pp.257-268
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    • 1997
  • The effects of water-and oil-repellent finishes on the deposition and removal of oily soils from polyseter fabrics were investigated in this study. The polyester fabrics treated with three kinds of fluoropolymers(TG-410H, TG-990) were soiled with mixed oily soils and washed by using Terg-O-Tometer at various conditions. It was found that TG-410H and TG-527 treated polyester fabrics reduced significantly the deposition of oily soils than untreated and TG-990 treated polyester fabrics. The removal of oily soils from polyester fabrics was increased in porportion to increasing of surfactant concentration up to a certain point(0.2% owb) but it levelled off above the point. The removal effect was high in the order of TG-990 treated polyester fabrics > untreated polyester fabrics > TG-527 treated polyester fabrics > TBG-410H treasted polyester fabrics. Especially the removal of oily soils from polyester fabrics was more effectively removed in triton X-100 solution. In general the removal of oily soils from polyester fabrics treated with fluoropolymers was increased up to a miximum near 6$0^{\circ}C$ and than decreased above 6$0^{\circ}C$. And efficient removal could be achieved within relatively short time (30min) The removal of oily soils from polyester fabrics was increased in proportion to increasing of pH range up to a certain point(9.5 or 11.0) but it began to decrease above the point. Furthermore the removal of oily soils was increased with th increase of mechanical agitation, but it began to decrease above 160 rpm.

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건조에 의한 준설 매립 지반에 물리적 특성변화 (Changes in Physical Properties of Dredged Soils by Drying)

  • 윤용한;김원태
    • 한국조경학회지
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    • 제34권2호
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    • pp.36-43
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    • 2006
  • This study was carried out to determine the ways in which drying improves and develops dredged soils which exist widely in the lowlands of Korea. Before drying there were large variations in the fundamental physico-chemical properties of dredged soils collected from different places. In the sample soils, saturated hydraulic conductivity decreased gradually with an increase in bulk density with the exception that in air-dried soils a reverse trend was observed. Also in the sample soils, the sedimentation volume and the consistency limits decreased gradually with the decrease in soil water content after the air-drying treatment. The porosity of the sample soils decreased from $0.67{\sim}0.87m^3/m^3\;to\;0.58{\sim}0.66m^3/m^3$ and the liquid-phase range decreased from $0.41{\sim}0.83m^3/m^3\;to\;0.29{\sim}0.71m^3/m^3$. The solid-phase range of sample soils increased $0.13{\sim}0.33m^3/m^3\;to\;0.24{\sim}0.37m^3/m^3$ same as above with air-drying treatment. In conclusion the air-drying treatment caused an irreversible effect on some physical properties. Accordingly, these facts indicate that the effects of air-drying treatment on these properties are considered to be resulted from irreversible changes in the structural status of the sample soils.

연약한 실트지반과 오염된 실트지반의 지지력 결정 (Determination of the Bearing Capacity of Soft and Polluted Silt Soils)

  • 안종필;박상범;박경호;유덕찬
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.940-947
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    • 2005
  • In this study, model tests of soft silt soils(ML) and silt soils was polluted with wastewater and waste oil from factories($ML_p$). Distribution of displacement, bearing capacity comparing the test results with existing theoretical expressions and analyzing the test results, the following conclusions were obtained. It was found out that in soft silt soils the relationship of critical surcharge and undrained cohesion is $q_{cr}=4.14C_u$ and polluted silt soils $ML_p$ those are $q_{cr}=1.78C_u$, respectively and the relationship of ultimate capacities $q_{ult}=9.53C_u$ and undrained cohesion in polluted silt soils are $q_{ult}=4.39C_u$. Critical surcharge and ultimate capacity is less in polluted silt soils than in soft silt soils.

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Monitoring of petroleum hydrocarbon degradative potential of indigenous microorganisms in ozonated soil

  • 안영희;정해룡;;;최희철;김인수
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2003년도 추계학술발표회
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    • pp.152-157
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    • 2003
  • Diesel-contaminated soils were ozonated for different times (0 - 900 min) and incubated for 9 wk to monitor petroleum hydrocarbons (PH)-degradative potential of indigenous microorganisms in the soils. Increased ozonation time decreased not only concentration of PH but also number of microorganisms in the soils. Microorganisms in the ozonated soils increased during 9-wk incubation as monitored by culture- and nonculture-based methods. Higher (1-2 orders of magnitude) cell number was observed by quantitative analysis of soil DNA using probes detecting genes encoding 165 rRNA(rrn), naphthalene dioxygenase (nahA), toluene dioxygenase (todC), and alkane hydroxylase (alkB) than microbial abundance estimated by culture-based methods. Such PH-degraders were relatively a few or under detection limit in 900-min ozonated soil. Further PH-removal observed during the incubation period supported the presence of PH-degraders in ozonated soils. Highest reduction (25.4%) of total PH (TPH) was observed in 180-min ozonated soil white negligible reduction was shown in 900-min ozonated soil during the period, resulting in lowest TPH-concentration in 180-min ozonated soil among the ozonated soils. Microbial community composition in 9-wk incubated soils revealed slight difference between 900-min ozonated and unozonated soils as analyzed by whole cell hybridization using group-specific rRNA-targeted oligonucleotides. Results of this study suggest that appropriate ozonation and subsequent biodegradation by indigenous microorganisms may be a cost-effective and successful remediation strategy for PH-contaminated soils.

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Extractable Micronutrients in Soils of Some Forested and Deforested Sites of South Eastern Hilly Areas of Bangladesh

  • Akhtaruzzaman, Md.;Osman, K.T.;Haque, S.M. Sirajul
    • Journal of Forest and Environmental Science
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    • 제34권6호
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    • pp.429-434
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    • 2018
  • Extractable iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) contents and their distribution with depths in soils of forested and adjacent deforested areas at Jahazpura, Teknaf, Cox's Bazar of Bangladesh were studied. The soils under forest showed higher levels of DTPA-extractable micronutrients in all three layers of soil in comparison to those of the deforested areas. The differences between forested and deforested sites were, in most cases, significant.. The top soils of forested sites had the higher contents of micronutrient and generally decreased with depth in forested soils, while there was no regular trend of distribution in deforested soils. The study also revealed that contents of extractable Fe, Mn and Cu were sufficient in all depths and sites but Zn was deficient in bottom layer of forested and all three layers of deforested sites. The results suggested that organic matter, clay and soil pH could play important roles in concentrations and distributions of micronutrients in soils of the study areas.

Radiation shielding properties of weathered soils: Influence of the chemical composition and granulometric fractions

  • Pires, Luiz F.
    • Nuclear Engineering and Technology
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    • 제54권9호
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    • pp.3470-3477
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    • 2022
  • Soils are porous materials with high shielding capability to attenuate gamma and X-rays. The disposal of radionuclides throughout the soil profile can expose the living organisms to ionizing radiation. Thus, studies aiming to analyze the shielding properties of the soils are of particular interest for radiation shielding. Investigations on evaluating the shielding capabilities of highly weathered soils are still scarce, meaning that additional research is necessary to check their efficiency to attenuate radiation. In this study, the radiation shielding properties of contrasting soils were evaluated. The radiation interaction parameters assessed were attenuation coefficients, mean free path, and half- and tenth-value layers. At low photon energies, the photoelectric absorption contribution to the attenuation coefficient predominated, while at intermediate and high photon energies, the incoherent scattering and pair production were the dominant effects. Soils with the highest densities presented the best shielding properties, regardless of their chemical compositions. Increases in the attenuation coefficient and decreases in shielding parameters of the soils were associated with increases in clay, Fe2O3, Al2O3, and TiO2 amounts. In addition, this paper provides a comprehensive description of the shielding properties of weathered soils showing the importance of their granulometric fractions and oxides to the attenuation of the radiation.

화훼작물이 재배된 온실 또는 노지재배지의 토양 화학성 비교 (Comparison of Soil Chemical Properties in Greenhouse or Open Field Where Flower Crops were Cultivated from 2018 to 2020)

  • 권혜숙;허성
    • 한국자원식물학회지
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    • 제35권5호
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    • pp.675-685
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    • 2022
  • 2018년부터 2020년까지 화훼작물의 시설 및 노지재배지의 토양 화학성을 비교 분석하였다. 시설재배지 토양의 pH는 3년간 적정 범위 유지되었고, 노지토양도 적정 범위로 유지되었다. 유기물 함량은 두 토양에서 모두 적정 범위로 유지되었고, EC의 경우 시설토양은 적정 기준보다 높았으나, 노지토양에서는 적정 기준 범위로 유지되었다. 유효인산은 시설토양에서 2018년에 560 mg/kg가장 높았으나 매해 낮아져 2020년에 적정 기준 범위로 낮아졌고, 노지재배지 토양은 매해 적정 범위에 유지되었다. 치환성 양이온은 시설재배지 토양에서 3년간 표준 범위보다 높게 유지되어 영양 불균형이 극심하였고, 특히 치환성 칼슘과 마그네슘의 유의성이 높았다. 그러나 노지재배지 토양에서는 치환성 칼슘과 마그네슘이 적정 범위보다 약간 높은 수준이었다. 주성분 분석을 통해서 시설재배지 토양의 치환성 양이온을 비롯해 유효인산, EC가 높은 문제점이 드러났으며, 노지재배지는 시설재배지보다는 상대적으로 낮은 값의 유효인산, EC, 치환성 양이온 분포를 보였다. 그러나 노지재배지 토양의 pH는 변동성이 너무 크고 pH가 높은 토양의 비율이 시설재배지보다 높았다. 또한, 노지재배지 토양은 시설재배지보다 유기물 함량이 낮으므로 유기물 시용에 더욱 적극적으로 노력해야 할 것으로 판단되었다.

만경강 하천토양에서 노랑꽃창포의 생장특성과 질소·인 제거효과 (Growth Characteristics and Removal Effect of Nitrogen and Phosphoric Acid of Iris pseudoacorus at Waterway Soils of Mangyeong River)

  • 서병수;최수민;박우진;박종민
    • 한국환경복원기술학회지
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    • 제7권5호
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    • pp.57-65
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    • 2004
  • This study was carried out to measure the growth and photosynthesis of Iris pseudoacorus, the reduction rate of nitrogen(T-N) and phosphoric acid($P_2O_5$) from soils, and the increase rate of two substance into plants which cultivated at waterway soils of different concentration of two substance. The results are summarized as follows; 1. The contents of nitrogen and phosphoric acid at waterway soils of Mangyeong river showed the highest level in the around Samrye railway bridge where was located in the downstream and sewage of stock raising flowed in 2. The Iris pseudoacorus which cultivated at waterway soils showed the leaf and root growth of 43~50 and 9~13cm, respectively. And the growth was higher in the waterway soils contained high level of nitrogen The rate of photosynthesis was $3.5-5.9{\mu}mol\;m^{-2}s^{-1}$ ranges and this rate increased from the end of June to August and then decreased. The rate of photosynthesis was higher in waterway soils contained high nitrogen regardless of seasons. 4. The Iris pseudoacorus removed nitrogen and phosphoric acid from waterway soils about 19~21% and 13~15%, respectively. The Iris pseudoacorus was effective to remove nitrogen more than phosphoric acid. And the waterway soil which included high concentration of two substance showed highly removal 5. The results of Iris pseudoacorus vegetation in the waterway soils showed that nitrogen and phosphoric acid of inside plant increased with 0.2-1.0% and 0.01-0.10% ranges, respectively. The contents of nitrogen and phosphoric acid in plants were increase in the soils of higher contents of nitrogen and phosphoric acid, and the rate of increase of nitrogen and phosphoric acid was higher at roots than leaves.

가축분 퇴비의 시용량에 따른 제주 밭토양의 부식의 형태별 함량 변화 (Changes of Humus Types Affected by Application of Animal Manures Compostin Jeju Upland Soil)

  • 황기성;유봉식
    • 한국환경농학회지
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    • 제24권4호
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    • pp.364-369
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    • 2005
  • 우리나라 최남단에 위치한 제주도에 가장 많이 분포하고 있는 화산회 밭 토양과 비화산회 밭 토양에 가축분 퇴비를 0, 50, 100, 150 ton/ha 해당량을 시용한 후 토양 부식의 함량 변화를 조사하여 문제점을 살펴본 결과는 다음과 같다. 부식의 분포도는 화산회 토양은 대부분 A type이었으며 일부 밭토양에서 B type에 속하여 화산회 토양은 부식화가 진행되었음을 알 수 있었으며 비화산회 밭토양은 대부분 Rp, B type으로 존재하여 동일한 결과를 얻을 수 없었다. 질산태 질소 함량과 부식함량과의 관계는 화산회 토양은 $R^2=0.5263$, 비화산회 양은 $R^2=0.524$의 정의 상관관계를 나타내었다. 탄소의 함량과 부식 함량과의 관계는 화산회 토양은 $R^2=0.469$, 비화산회 밭 토양은 $R^2=0.550$의 정의 상관관계를 보이고 있다.