• Title/Summary/Keyword: physical soil properly

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A Study on the Physical and Chemical Characteristics of the Constructed Wetland Soil for Sewage Treatment (오수처리용 인공습지내 토양의 이화학적 특성조사)

  • Yoon, Chun-Gyeong;Kwun, Tae-Young;Woo, Sun-Ho
    • Journal of Korean Society of Rural Planning
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    • v.5 no.2 s.10
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    • pp.24-29
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    • 1999
  • The soil from constructed wetland system for sewage treatment was analyzed to examine physical and chemical characteristics. Clogging and lowered permeability were the physical matters of concern, and nutrient and salt accumulation were the chemical matters of concern. However, the soil properties of the constructed wetland system after 3 year operation demonstrated no degradation and still the soil works almost same as the initial stage. Encouragingly, no sludge accumulation was observed inside the system. Therefore, it implies that the wetland sewage treatment system can work continuously as long as it is operated and managed properly not to cause excessive pollutant loading.

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Soil Physical and Hydraulic Properties over Terrace Adjacent Four Major Rivers

  • Lee, Kyo Suk;Lee, Jae Bong;Lee, Myoung Yun;Joo, Ri Na;Lee, Dong Sung;Chung, Doug Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.3
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    • pp.235-241
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    • 2016
  • The soil does not only serve as a medium for plant growth but also for engineering construction purposes. It is very weak in tension, very strong in compression and fails only by shearing. The behaviour of the soil under any form of loading and the interactions of the earth materials during and after any engineering construction work has a major influence on the success, economy and the safety of the work. Soils and their management have therefore become a broad social concern. A limitless variety of soil materials are encountered in both agronomy and engineering problems, varying from hard, dense, large pieces of rock through gravel, sand, silt and clay to organic deposits of soft compressible peat. All these materials may occur over a range of physical properties, such as water contents, texture, bulk density and strength of soils. Therefore, to deal properly with soils and soil materials in any case requires knowledge and understanding of these physical properties. The desired value of bulk density varies with the degree of stability required in construction. Bulk density is also used as an indicator of problems of root penetration,soil aeration and also water infiltration. This property is also used in foundation engineering problems. While not conforming to standard test procedures, this work attempts to add to the basic information on such important soil parameters as water content, bulk density.

Influences of Physical Soil Properties on Drought Severity in the Central Great Plains Based on Satellite Data and a Digital Soil Database (인공위성자료와 디지털 토양자료를 통해 분석한 미중부 대평원 지역 가뭄정도에 미친 물리적 토양특성의 영향)

  • Sunyurp Park
    • Journal of the Korean Geographical Society
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    • v.38 no.6
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    • pp.935-948
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    • 2003
  • The State Soil Geographic (STATSGO) database is a valuable source for assessment of soil properties at a state level. Using GIS techniques, eight physical soil properties were extracted from the database, including available water capacity, clay content, soil depth, slope, depth to water table, drainage, texture, and permeability. The influences of these soil properties on drought severity, which was estimated by NDVI departures from normal, were determined over western-central Kansas. Study results showed that seven soil properties had significant relationships with drought severity with correlation coefficients, ranging from -0.89 to 0.85. Thermal emission signals from the Moderate Resolution Imaging Spectroradiometer (MODIS) had a significant relationship with drought severity expressed by NDVI departure from normal and represented spatial progression of drought over time well. High thermal signals, indicating high soil moisture deficit, emerged in the western region and their spatial distribution changed over time. Different sets of soil factors influenced drought severity among early-drying and late-drying areas.

An Experimental Study on Optimal Mixture Ratio of Hardening Agent for Surface Soil Stabilization (연약지반 표층안정처리를 위한 고화재의 최적조합 산정에 관한 실험적 연구)

  • 천병식;김진춘;최현석
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11a
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    • pp.17-24
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    • 2000
  • Hardening agent has been the traditional material for surface soil stabilization of soft ground. This study aims at determining optimal mixture ratio of hardening agent in accordance with the required design specifications. Hardening agent is properly mixtured with Fly ash, Gypsum, Slag and Cement for the ettringite hydrates which is effective for early stabilization of unconsolidated soil. The treated soil is the clay which are widely found here and there in Korea. In this study, preliminary tests were performed to get optimal mixture ratio of stabilizer ingredient, and marine clay in Jin-Hae was used to get physical and chemical properties. Laboratory tests of 50 stabilized soil were peformed to get optimal mixture ratio for 16 stabilizer material of 6 type, and stabilizer mixing was determined.

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Review of Management Methods and Criteria for Environmentally-Sound Soil (친환경 토양 관리 방법과 기준에 대한 평가)

  • Ryu, Jin-Hee;Lee, Kyo-S.;Chung, Doug-Y.
    • Korean Journal of Agricultural Science
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    • v.35 no.1
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    • pp.53-67
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    • 2008
  • The principle goal of environmentally-friendly agriculture is to maintain and conserve water and agriculture environment including drinking water resources by properly using agricultural materials such as agricultural chemicals, chemical fertilizers, and other agricultural materials according to act 19 of foster law of environmentally-friendly agriculture. To achieve these goals, we have to establish Integrated Nutrient Management(INM) and Integrated Pesticide Management(IPM) which are most important core technologies for environmentally-friendly rice cultivation. However, there are lack of criteria and technology for evaluation category according to soil management and its soil classes to practice an environmentally-friendly agriculture. Therefore, we should eatablish the standards to produce the safe agricultural products based on the soil physical and chemical characteristics which are basic properties of soil to accomplish the principle aims of environmentally-friendly agriculture.

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Analysis and Improvement Practise of Drainage Problem on Soil Profile at the Golf Course Fairway (골프코스 페어웨이 지반 토양의 배수불량 원인과 개선방안)

  • Lee, Jung-Ho;Jung, Gi-Rai;Lee, Jong-Min;Joo, Young-Kyoo
    • Asian Journal of Turfgrass Science
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    • v.26 no.2
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    • pp.129-134
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    • 2012
  • Research was focused on the improvement of poor drainage problems on golf course fairway which had not been performed soil test or properly amended during the course construction. The analysis of the drainage problem basically was caused by a deterioration of soil physical properties by the top layer compaction. The soil hardness reached about 3,000 Kpa around 5~6 cm of soil profile. The slow infiltration speed to subsoil by the compaction was caused directly a poor drainage capacity. However, the properly amended sand soil showed an apparent value of 1,500 Kpa through the subsoil. The water content test showed a similar result that higher rate of 20~30% and ideal rate of 8~12% at poor drainage area and successfully amended area, respectively. However, an imported topsoil media which had higher content of silt and clay from a trans-planted sod had made a heterogeneous soil profile and that caused a poor drain capacity by a low infiltration rate. Those drainage problems triggered to buildup a reduced soil layer by poor soil gas exchange. The soil environment of deoxidation enhanced anaerobic microbial population and induced methane gas build-up to 55 ppm, and that resulted an adverse effect on turf growth by root growth retardation, consequently.

The Estimation of Physical/Biological Parameters of Greenhouse Soil by Image Processing (컬러 영상처리에 의한 시설재배지 토양의 생물 물리적 환경변수 추정)

  • Kim, H.T.;Kim, J.D.;Moon, J.H.;Lee, K.S.;Kang, K.H.;Kim, W.;Lee, D.W.
    • Journal of Biosystems Engineering
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    • v.28 no.4
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    • pp.343-350
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    • 2003
  • This study was conducted to find out the coefficient relationships between intensity values of image processing and biological/physical parameters of soil in greenhouses. Soil images were obtained by an image processing system consisting of a personal computer and a CCD earners. A software written in Visual C$\^$++/ systematically integrated the functions of image capture, image processing, and image analysis. Image processing data of the soil samples were analyzed by the method of regression analysis. The results are as follows. For detecting soil density of unbroken soil samples, the highest correlation coefficients of 0.82 and 0.84, respectively were obtained fur R-value and S-value among image processing data while it was 0.97 for G-value. Considering the relationship between biological characteristics and image processing data of soil in greenhouse, the correlation was found generally low. For pH of unbroken soil sample, the correlation coefficients were found 0.87, 0.85, and 0.94, respectively with G, I, and H values of image processing data. In the case of bacteria, any correlation was not found with the image processing data For Actinomyctes, they were 0.86 and 0.85, respectively with G-value and B-value of image processing data showing high correlation coefficient compared to the other variables. The correlation coefficient between Fungi and H-value was shown 0.88, the highest among the variables higher than 0.8 while the other variables showed low correlation. For broken soil samples from greenhouse, the relation between biological parameter and image processing data were rarely shown in this study. The results of this study indicated that most of correlation coefficient between the variables were usually lower than 0.01. Accordingly, it was assumed that the soil should be used without broken to fairly estimate biological characteristics using CCD camera.

Review of Assessing Soil Quality Criteria for Environmentally-Sound Agricultural Practics and Future Use (환경적으로 안전한 농업과 미래용도를 위한 토질 기준 평가 검토)

  • Doug Young Chung
    • Journal of Korea Soil Environment Society
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    • v.3 no.2
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    • pp.127-145
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    • 1998
  • Unlike water or air quality standards that have been established by legislation using potential human health impact as the primary criterion, soil quality depends on the soils primary function and its relevant environmental factors, which is much more site- and soil specific. A properly characterized soil quality assessment system should serve as an indicator of the soil capacity to produce safe and nutritious food, to enhance human and animal health, and to overcome degrative processes. For our proposed example, a high quality soil with regard to maintaining an adequate soil productivity as a food production resources must accommodate soil and water properties, food chain, sustainability and utilization, environment, and profitability, that (i) facilitate water transfer and absorption, (ii) sustain plant growth, (iii) resist physical degradation of soil, (iv) produce a safe food resources, (v) cost-effective agricultural management. Possible soil quality indicators are identified at several levels within the framework for each of these functions. Each indicator is assigned a priority or weight that reflects its relative importance using a multi-objective approach based on principles of systems to be considered. To do this, individual scoring system is differentiated by the several levels from low to very high category or point scoring ranging from 0 to 10, And then weights are multiplied and products are summed to provide an overall soil quality rating based on several physical and chemical indicators. Tlne framework and procedure in developing the soil quality assessment are determined by using information collected from an alternative and conventional farm practices in the regions. The use of an expanded framework for assessing effects of other processes, management practices, or policy issues on soil quality is also considered. To develop one possible form for a soil quality index, we should permit coupling the soil characteristics with assessment system based on soil properties and incoming and resident chemicals. The purpose of this paper is to discuss approaches to defining and assessing soil quality and to suggest the factors to be considered.

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Characteristics of Artificial Soils Produced from Sludge (슬러지를 이용하여 생산한 인공토양의 특성)

  • Yoon, Chun-Gyeong;Kim, Sun-Joo;Kwun, Tae-Young;Lee, Nam-Chool
    • Korean Journal of Environmental Agriculture
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    • v.17 no.3
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    • pp.200-204
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    • 1998
  • Physical and chemical properties of artificial soil produced by firing process were analyzed and compared with normal dry field soil and soil quality standards. Material used for production was water and wastewater treatment sludge, chabizite, and lime. The mixed material was thermally treated in the firing kiln at about $300^{\circ}C$ and $1,000^{\circ}C$, respectively, as per designed process. General properties of the artificial soil were classified as sand by unified soil classification method and similar to the dry-field soil, and even soil conditioning effect were expected when it is mixed properly with normal soil. The artificial soil is high in pH and permeability compared to the dry-field soil. Heavy metal concentrations of the artificial soil met the soil quality standards for the farmland. Overall, the artificial soil was thought to be an appropriate soil which can be returned safely to the nature without significant adverse effect. The cost for the artificial soil production process needs to be lowered for practical application as a sludge treatment, therefore, commercializing of the artificial soil is under review.

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Infiltration Rates of Liquid Pig Manure with Various Dilution Ratios in Three Different Soil (돈분액비 토양침투율과 토양내 분포 특성)

  • Shim, Ho-Young;Lee, Kyo-Suk;Lee, Dong-Sung;Jeon, Dae-Sung;Park, Mi-Suk;Shin, Ji-Su;Lee, Yun-Koung;Goo, Ji-Won;Kim, Soo-Bin;Song, Seong-Geun;Chung, Doug-Young
    • Korean Journal of Environmental Agriculture
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    • v.33 no.3
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    • pp.164-168
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    • 2014
  • BACKGROUND: Increase in application of liquid pig manure(LPM) in agriculture as nutritional source has become a social issue due to its influence on water quality. Also, proper application methods have not been developed with respect to indigenous properties of LPM and soil physical properties. Therefore, we conducted this experiment to observe the infiltration characteristics and distribution of dissolved organic compounds of LPM in soils having different soil textures. METHODS AND RESULTS: To do this experiment, we collected three different soils and LPM. We analyzed the physical and chemical properties of both soils and LPM to determine the dilution ratios of LPM. The LPM diluted to 4 different ratios with distilled water was applied to the top of soil column. Infiltration rates were observed by time and depth until the amount of effluent collected from the bottom of the soil columns were stabilized while maintaining the hydraulic head 3 cm above the soil column. The results showed that infiltration rates increased with increasing dilution ratios in the order of sandy, loamy sand, and sandy loam. The time required to reach steady state was increased with decreasing sand contents clay. CONCLUSION: The size and amount of the dissolved organic compounds in LPM that can determine the efficiency as fertilizer and environmental problems as nonpoint pollution source in water quality have not been investigated with respect to behavior and transport of them in soil. Therefore, it requires further research how we can properly apply LPM as valuable fertilizer substitute for inorganic fertilizers.