• 한국환경농학회지
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• 제20권5호
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• pp.317-324
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• 2001

Short-term effect of phosphogypsum on soil properties including acidification, salinity and metal availability were investigated under laboratory and field conditions. Phosphogypsum and mixtures of phosphogypsum and compost were added to soil and incubated in a laboratory condition with 15% moisture content. Phosphogypsum treatments were 2.5 and 5.0 g/kg soil and in the treatments of phosphogypsum and compost mixture 10 g of compost was added additionally. After the 30 days of incubation, an additional phosphogypsum and/or compost were added to the remaining soils at the same rates of the first treatments. pH, electrical conductivity, and available hazardous elements were measured periodically during the incubation. Field experiment was conducted in a plastic film house of mellon with four treatments of phosphogypsum and compost mixtures - 25+125, 50+125, 50+250 and 100+250 kg/165 $m^2$. pH, electrical conductivity, and hazardous elements in soil and total hazardous elements in leaf were measured. In the laboratory experiment, after 30 days of the first phosphogypsum application, soil pHs were lowered by 0.7-0.8 units. After the second treatment of phosphogypsum 0.2 units of additional acidification occurred. However, acidification was not observed in the soils treated with mixtures of phosphogypsum and compost. In the laboratory experiment, phosphogypsum treatments increased electrical conductivity very significantly. In field experiment, pH and electrical conductivity of soils treated with phosphogypsum were nearly the same as those of soil not treated with phosphogypsum. Since soil condition in the field study was an open system, the free acids and salts derived from phosphogypsum could be diffused down with water leaching through the soil profile and then any significant acidification or salt accumulation in the topsoil could not be observed. In both laboratory and field experiments, levels of available hazardous elements in soils treated with phosphogypsum were quite low and not different from the levels found in the control soil. Results obtained from this study suggest that application of phosphogypsum at appropriate rates on agricultural land appears of no concern in terms of acidity, salinity and hazardous element content of soil.

• Journal of Plant Biology
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• 제12권4호
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• pp.9-18
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• 1969

In the previous paper(part III), a certian relationships between the changes of chlorinity and organic acid released from organic material were seemed to be concened to each other in saline soil suspension. Such a possibility had been a cause to take this experiments and this experiment was carried out under the treatment of organic acid crystal, oxalic acid and succinic acid, to the soil suspension(soil: water=20g:40cc) directly. The amount of organic acid treated to the suspension were related to the contents of organic material, as amount of organic acid per gram of organic material(391.76mg). The saline soil suspension were grouped and treated with the acids in order of 78.35mg(Group 1), 391.76mg(Group 2) 979.4mg(Group 3), and 1958.8mg(Group 4), respectively. Treated suspension had been incubated at room temperature and extract from suspension was used for analysis. Followings are summary of this report. 1) Changes of pH in soil suspension appeared a little increase after the treatment of organic acid until 168 hours. 2) Total acidity of soil suspension showed a variation, however, the values of total acidity appeared not to be increased or decreased during the period of experiment. 3) Sugar contents of soil suspension was increased until 168 hours after treatment. These results are similar tendency to the previous paper. 4) Addition of organic acid to soil suspension was confirmed not to be effective method for desalination from saline soil. Chlorinity of group 3 and 4 which were treated with high concentration of organic acid showed a decrease comparing to control group.

• 한국토양비료학회지
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• 제43권1호
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• pp.25-35
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• 2010

약간 경사가 있고 침식 가능성이 높은 배나무 과수원 포장에서 2가지 종류의 제초제를 처리하여 유거수와 토양침식의 변화를 관찰하였다 : (1)발아 전 처리 제초제 - Glyphosate; (2)발아 후 처리 제초제 - Paraquat. 조사지 포자의 고도는 125 m 경사도는 5.5% ~ 10.2%의 분포를 보였다. 한편 조사기간인 2006년 6월과 2008년 11월 사이의 강우 횟수는 각각 47, 52, 52회로 조사되었다. 정상적인 침투율은 보통 잡초가 모두 제거된 맨땅에서 증가하지만 제초제가 처리된 땅에서는 감소했다. 대조구에서 유거수는 항상 제초제를 처리한 땅과 맨땅에서 보다 더 적었다. 같은 강우강도에서 유거수는 대조구, glyphosate 그리고 paraquat 순으로 증가하였다. 강우의 강도가 센 경우에 유거수 차이는 조사 첫해에 약간 더 높았다. 토양 유실은 연구기간 3년 동안 약간씩 다르나 조립질 토양보다 미세질토양에서 유실이 더 많았다. 하지만 토양유실은 총강우량과 유거수와는 밀접한 연관이 없는 것으로 조사되었다. 동일 강우강도에서 토양침식률은 대조구, glyphosate, paraquat 그리고 glyphosate가 처리된 맨땅 순으로 증가하였다. 상대적으로 30 mm $day^{-1}$보다 낮은 강우량에서 제초제 처리와 상관없이 토양유실에 미치는 영향은 차이가 없었다. 결과적으로 토양침식에서 중요한 요인은 강우강도이다.

• 한국토양비료학회지
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• 제41권6호
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• pp.415-418
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• 2008

폐기물 연용토양의 미생물 군집 분석을 위해 공단지역 하수 슬러지 처리등 16처리(3수준)에 대하여 가장 좋은 방법을 찾고자, RFLP, CLSU, PLFA, TGGE 의 4가지 방법을 이용하였으며, 이들 4가지 방법에 대하여 시기별 군집변동 조사를 통한 통계적 비교 분석을 하였다. 그 결과, 미생물의 경시적 군집 변동상 관찰은 PLFAs (Phospholipid Fatty Acids) 방법이 가장 효율적이었으며 RFLP는 많은 종류의 제한 효소의 사용이 필요하다. TGGE는 DNA 추출을 통해 비배양학적인 분석에서는 가장 좋은 방법이나 PCR조건 등 실험 과정에서 토양종류에 따라 민감하게 반응하여 비슷한 조성의 토양분석에 효율적이라고 생각한다.

• 생명과학회지
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• 제14권5호
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• pp.778-787
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• 2004

유기물이 풍부한 토양에서 분리하여 동정한 Bacillus stearothermophilus DL-3와 미강을 사용하여 미생물 제재를 제조하고 미생물 제재의 처리가 상추(적치마 상추)와 배추(가락 신1호 배추)재배 토양의 미생물상에 미치는 영향 및 상추와 배추의 생장에 미치는 영향을 조사하였다. 미생물 제재를 처리 한 6주 후, 미생물 제재를 처 리 한 토양에 존재하는 토양 미생물의 총 균수는 미생물 제재를 처리하지 않은 토양에 존재하는 토양 미생물의 총 균수에 비하여 미생물 제재를 처리한 양에 비례하여 많음을 확인하였다. 미생물 제재를 처리한 토양에서 재배한 상추와 배추의 생육이 미생물 제재를 처리하지 않은 토양에서 재배한 상추와 배추에 비하여 빠름을 확인하였다. 미생물 제재를 처리한 토양에서는 처리하지 않은 토양에 비하여 전체적인 토양 미생물 수의 증가와 작물의 생장에 유용한 종류의 미생물이 상대적으로 증가하기 때문에 상추와 배추의 생장을 촉진시킨다고 판단된다.

• 한국유기농업학회지
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• 제12권3호
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• pp.345-352
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• 2004

This study was carried out to investigate the effect of soil-born microorganism, vitabio on growth of leaf lettuce in the vinyl house. Total weights of leaf lettuce treated with vitabio showed difference compared with untreated leaf lettuce. Sugar content was also increased. Mineral contents of leaf lettuce showed no difference between treated with vitabio and untreated with vitabio. Exchange Capacity (EC) and Organic Matter (OM) in chemical properties of soil treated with vitabio showed higher than soil in untreated vitabio. Vitabio treated soil contained much more microorganisms such as Bacteria, Actinomycetes, Hyphomycetes, Bacillus sp. Pseudomonas sp. after harvest.

• 한국의류학회지
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• 제3권1호
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• pp.13-18
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• 1979

Many researches have found that the anionic surfactants are effective when the anionic soil is attached to the cotton fabrics. However, this research investigated the relationship of the super soil removal and surfactants when the anionic and cationic soil was attached to the cationic cotton fabrics. The result is that the cationic surfactants are vary effective for soil removal in the cationic cotton fabrics. The processing and nature of cationic cotton fabrics are treated and investigated as follows: Cotton fabrics are heated in the presence of ethylenimine and acetic acid dissolved in benzene to contain a significant amount of fixed nitrogen. Some polymer was formed but removal by washing with benzene and water. The optinium molor ratio of acid-to-ethylenimine seemed to be in the range 1: 10. The treated cotton fabrics dyed with acid Orange II dyes, and nitrogen content in the treated cotton fabrics were determined by the Kjeldahl method.

• Geomechanics and Engineering
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• 제21권4호
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• pp.337-348
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• 2020

Tropical organic soils having more than 65% of organic matters are named "peat". This soil type is extremely soft, unconsolidated, and possesses low shear strength and stiffness. Different conventional and industrial binders (e.g., lime or Portland cement) are used widely for stabilisation of organic soils. However, due to many factors affecting the behaviour of these soils (e.g., high moisture content, fewer mineral particles, and acidic media), the efficiency of the conventional binders is low and/or cost-intensive. This research investigates the impact of different constituents of cement-sodium silicate grout system on the compressibility behaviour of organic soil, including settlement and void ratio. A microstructure analysis is also carried out on treated organic soil using Scanning Electron Micrographs (SEM), Energy Dispersive X-ray spectrometer (EDX), and X-ray Diffraction (XRD). The results indicate that the settlement and void ratio of treated organic soils decrease gradually with the increase of cement and kaolinite contents, as well as sodium silicate until an optimum value of 2.5% of the wet soil weight. The microstructure analysis also demonstrates that with the increase of cement, kaolinite and sodium silicate, the void ratio and porosity of treated soil particles decrease, leading to an increase in the soil density by the hydration, pozzolanic, and polymerisation processes. This research contributes an extra useful knowledge to the stabilisation of organic soils and upgrading such problematic soils closer to the non-problematic soils for geotechnical applications such as deep mixing.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.43-44
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• 2016

Large amount of dredged sea soil is produced in southeast seashore region in during harbor maintenance. Disposal of dredged sea soil has become difficult due to the environmental regulation. Therefore, disposal of dredged sea soil method is to landfill. But, the capacity of the landfill limit state and if the size of the dredged sea soil is in the range of silt or clay, it cannot be used as reclamation material because ground subsidence occur. In this study, analyzed the pozzolanic activity of dredged sea soil. Analysis of the results showed a pozzolanic activity of dredged sea soil. In addition, incorporation of heat treated dredged sea soil increase both 28 and 56 day compressive strength of mortar specimen.

• Journal of the Korean Wood Science and Technology
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• 제33권6호통권134호
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• pp.87-94
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• 2005

본 연구는 지접부용 처리목재의 지하부에서 발생하는 방부제 유효성분의 용탈에 관한 연구로 토양의 물리 및 화학적 특성이 방부제 유효성분의 용탈에 미치는 영향을 파악하기 위하여 수행하였다. CCA 처리 라디에타소나무 시편을 국내의 대표적인 네 가지 토양(미사질양토, 양토, 사질양토, 사토)에 매립하여 12주간의 용탈기간 동안 토양이 항상 물로 포화된 상태가 유지되도록 토양 용탈시험을 실시하였으며, 토양 용탈시험 결과와 비교할 목적으로 물 용탈시험을 병행하여 실시하였다. 토양 종류에 따른 처리목채로부터 방부제 유효성분의 용탈을 차이가 관찰되었으나 토양 용탈은 물 용탈보다 유효성분의 용탈율이 낮았다. CCA 처리목재로부터 크롬, 구리, 비소 용탈율은 각각 사질양토, 양토, 사토에서 가장 높았으며, 모든 유효성분의 용탈율이 미사질양토에서 가장 낮았다. 토양의 물리 및 화학적 특성과 용탈율 간의 관계를 살펴본 결과, 방부제 유효성분의 용탈율이 토양 특성에 의해 매우 상이하게 영향을 받음을 알 수 있었다. CCA 처리목재로부터 구리 용탈은 토양내 치환성 마그네슘 및 염기총량의 영향을 받았다. CCA 처리목재로부터 크롬 용탈은 토양내 치환성 마그네슘($Mg^{2+}$) 함량의 영향을 받았으며, 비소 용탈은 토양내 치환성 칼륨($K^+$), 중금속인 니켈(Ni), 망간(Mn), 철(Fe), 크롬(Cr), 구리(Cu) 함량의 영향을 받았다. 본 연구 결과와 기존 연구 결과들 간에, 그리고 기존 연구결과들 간에도 토양 특성과 방부제 유효성분 용탈율 간의 관계가 서로 상이하게 보고되고 있다. 따라서 앞으로 이에 대한 보다 심도 있는 연구가 필요하리라 판단된다. 또한 실험실 규모의 용탈시험을 통해 얻은 본 연구의 결과를 입증하기 위해서 수분 조건과 토양 미생물의 종류와 분포가 상이한 실제 야외 지접부 환경에서의 연구가 반드시 필요하다.