• Title/Summary/Keyword: Soil Property

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A Study on Permeability of Stratified soil in the Close State Under Existence of Stagnant Water. (담수상태에 있어서 성층토양의 물의 침투에 관한 연구)

  • 조경용
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.16 no.3
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    • pp.3477-3491
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    • 1974
  • Following are the results of the study on the property of falling permeation of stratified soil in the close state under existence of stagnant water on a soil layer. 1. When on the stratified soil a least permeating layer was put on the soil layer the load Pressure was present owing to appearance of saturation close state driving decrease of the pressure in the lower layer, on the other hand when the least permeating layer was placed under the layer the lower least permeating layer pressure was decreased. 2. In the case of least permeating layer the variation of current gradient according to the respective level after treating the layer was enormous and due to usal storage phenomena for the Kl layer which was coarse that was trifle. 3. The permeability of the respective layer of stratified soil in the close state died not always coincide with that of single layer. 4. Generally Zunker's equation of average permeability was valid but actually calculated permeating velocity after treating the layer of stratified soil was seriously differ from the measured value owing to the variation of current gradient, especially when the pressure head at the layer boundany was discontinuous the validity of the equation of average permeability was seemed to be doubtful. 5. The permeating velocity of stratified soil was regulated by the least permeating layer, i.e. it is thought to be rational to estimate the value by calculating the current gradient with its proper permeability, pressure headon the layer and its thickness.

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Effect of particle size and scanning cup type for near infrared reflection on the soil property measurement

  • Ryu, Kwan-Shig;Cho, Rae-Kwang;Park, Woo-Churl;Kim, Bok-Jin
    • Near Infrared Analysis
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    • v.1 no.2
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    • pp.35-39
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    • 2000
  • The purpose of this research was to find out suitable soil sample preparation and sample holding tools for NIR reflection radiation for estimating soil components. NIR reflectance was scanned at 2nm intervals from 1,100 to 2,500nm with an InfraAlyzer 500(Bran+Luebbe Co.). Coarse(2.0mm) and fine(0.5mm) soil sample and various sample holding tools were used to obtain mean diffuse reflection of the soil for the calibration and validation of the calibration set in estimating moisture, organic matter and total nitrogen of the soils. Multiple linear regression was used to obtain the best correlation of NIR spectroscopy method. Correlation of NIR spectroscopy method. Correlation of NIR spectra for finely and coarsely sized soil did not show much difference. The standard errors of prediction(SE) using different types of sample holding tools for organic matter, total nitrogen and soil moisture were better than 0.765, 0.041 and 0.63% respectively. From the results it can be concluded that NIR spectroscopy with flow type cell could be used as a fast routine testing method in quantitative determination of organic matter, total nitrogen and soil moisture.

A Similitude Study of Soil-Wheel System for Inentifying the Dimension of Pertinent Soil Parameter (II) -Sinkage Prediction Analysis- (구동륜(驅動輪)의 성능예측(性能豫測)에 적합한 토양변수(土壤變數)의 차원해석(次元解析)을 위한 차륜(車輪)-토양(土壤) 시스템의 상사성(相似性) 연구(硏究)(II) -침하량(沈下量) 예측(豫測) 분석(分析)-)

  • Lee, K.S.;Chung, C.J.
    • Journal of Biosystems Engineering
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    • v.14 no.3
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    • pp.158-167
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    • 1989
  • This study was conducted to investigate the applicability of true model theory in a powered lugged wheel-soil system and to examine the possibility of using principles of similitude in investigating the dimensions of soil parameters pertinent to a powered lugged wheel-soil system concerning the sinkage prediction. The following conclusions were derived from the study; 1) The sinkage of prototype wheels proved to be predicted by those of the model wheels for the range of the dynamic weight tested. 2) A conditional equation which can be used for the prediction of sinkage of prototype by model test was derived as $n_f=n{_\ell}{^{-b}}$. The range of the numerical value of b, which is the exponent on the length dimension of the soil property ${\alpha}$, was found to be -1.48~-2.54. 3) Considering a relatively wide variation of b values, it was concluded that there are several soil properties which are pertinent to the powered lugged-wheel soil system concerning the sinkage prediction.

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Effect of Rice Bran and Wood Charcoal on Soil Properties and Yield of Continuous Cropping of Red Pepper

  • Won, J.G.;Jang, K.S.;Hwang, J.E.;Kwon, O.H.;Jeon, S.G.;Park, S.G.;Park, K.C.;Suh, Y.J.
    • Korean Journal of Organic Agriculture
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    • v.19 no.spc
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    • pp.218-221
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    • 2011
  • To improve the soil properties of physical and microbial community rice bran and wood charcoal were applied in the continuously cultivated plastic film house soil. Soil physical properties were improved by application of rice bran and charcoal compared to chemical fertilizer application (control) by 8~14% in bulk density and 5~9% in soil porosity. Changes in the biological ratio indexes of fatty acids in the soils were detected depending on the inputted materials. Especially in application of rice bran including mixture with charcoal, much more fungi and less bacteria were detected and the ratio of fungi to bacteria was increased, suggesting the more organic carbon metabolically active in these treatments. The high ratio of aerobe to anaerobe suggested the better aerobic conditions were in the soil inputted wood charcoal. From these results, it is important and possible to select some materials for the organic pepper cultivation, which may improve the poor condition soil.

Relationship between Soil Management Methods and Soil Chemical Properties in Protected Cultivation

  • Kang, Yun-Im;Lee, In-Bog;Par), Jin-Myeon;Kang, Yong-Gu;Kim, Seung-Heui;Ko, Hyeon-Seok;Kwon, Joon-Kook
    • Korean Journal of Environmental Agriculture
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    • v.28 no.4
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    • pp.333-339
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    • 2009
  • Various cultural practices have been promoted as management options for enhancing soil quality and health. The use of soil management methods can cause changes in fertility by affecting soil chemical properties. This study aimed to evaluate interactions between soil chemical properties and soil management methods in protected cultivation, and to classify soil management methods that similarly affect soil chemical properties. Water-logging and irrigation reduced soil pH and available $P_2O_5$ content. Application of animal manures has a positive effect on levels of organic matter, Av.$P_2O_5$, K, Zn, and Cu. The electrical conductivites tened to be low in the application of organic amendments, including rice and wood residues. Deeper plowing caused a reduction in Ca content. Practicing soil nutrient-considering fertilization and fertigation did not exert an influence on nutrient element contents. In a cluster analysis of the soil management methods according to major nutrients, low similarities were found with deeper plowing and crop rotation with rice in comparison with other practices. In a cluster analysis by minor nutrient characteristics, crop rotation and application of animal manures and rice residues were linked at a high Ward's distance, while other practices were found to be relatively low distinct. Each soil management method has a similar or different effect on soil chemical properties. These results suggest the necessity of establishing limits and standards according to the effects of soil management methods on soil chemical properties for economic soil practices.

Soil Quality Assessment Method of Paddy and Upland (논과 밭토양의 질 평가 방법)

  • Yoon, Jung-Hui;Jung, Beung-Gan;Jun, Hee-Joong;Kwak, Han-Kang
    • Korean Journal of Soil Science and Fertilizer
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    • v.37 no.6
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    • pp.357-364
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    • 2004
  • Modern agriculture depending on chemicals such as fertilizers and pesticides gave rise to questions about long-term sustainability of agriculture in relation to degradation of soil quality. Improving soil quality is prerequisite to sustain biological productivity, maintain environmental quality, and promote plant and animal health. Assessment and monitoring of the health and quality of soil is necessary to provide opportunity to evaluate and redesign soil management system for sustainability. To develop the soil quality assessment method, we collected national data on soil properties of paddy and upland and attempted to evaluate the data in aspect of soil quality by the process of selecting a minimum data set (MDS), scoring the soil properties and calculating soil quality index (SQI) integrating the score of each soil property. This approximation indicated that soil quality index was in the order of paddy soil, upland soil and plastic film house soil.

Soil Properties of Chestnut (Castanea crenata) Stands by Regions in Gyeongnam Province (경상남도 밤나무임지의 지역별 토양특성)

  • Kim, Choonsig;Lim, Jong-Taek;Cho, Hyun-Seo;Goo, Gwan-Hyo
    • Journal of Korean Society of Forest Science
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    • v.96 no.1
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    • pp.89-95
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    • 2007
  • This study was carried out to evaluate soil properties by regions from chestnut (Castanea crenata Sieb. et Zucc) stands in Gyeongnam province. Soil physical and chemical properties were measured from soil samples of top 20 em collected from three hillslopes (upper, middle, lower) of the chestnut stands in six regions (Jinjusi, Sacheonsi, Sancheonggun, Hadonggun, Goseonggun, Hapcheongun) where are major chestnut cultivation areas throughout the province. Soil properties were significantly different among regions (p<0.05), while were not significantly different among hillslopes (p>0.05). Soil bulk density, soil pore space, soil pH, organic matter content, total nitrogen, available phosphorus, and CEC were significantly different among regions (p<0.05). Soil bulk density was significantly lower (p<0.05) in Hadonggun ($0.96g/cm^3$ than in other regions ($1.12{\sim}1.22g/cm^3$). Soil pH was below pH 5.03 in most regions and Sancheonggun showed the lowest soil pH value (pH 4.62), followed by Jinjusi, Hadonggun, Hapcheongtm, Goseonggun, and Sacheonsi. Organic matter content was highest in Hadonggun (6.46%), while other regions ranged between 2.93% and 3.47%. Total nitrogen content showed a similar trend like the organic matter content. Available phosphorus was above 100 ppm in Jinjusi, Hadonggun and Sancheonggun, but Sacheonsi showed the lowest concentration (15 ppm) among the regions. Cation Exchange Capacity (CEC) was above 10 cmolc/kg in Goseonggun and Hadonggun, but below 8.6 cmolc/kg in Jinjusi and Hapcheongtm. Potassium content ranged between 0.07 and 0.14 cmolc/kg, and magnesium was above 0.66 cmolc/kg in all regions. The results indicate that soil property in chestnut stands was different among regions in Gyeongnam province. This suggested that the chestnut stands should be managed by the fertilization application reflected in the variability of regional soil property in chestnut stands.

Changes in Chemical Property of Soil Affected by Termites (Reticulitermes speratus kyushuensis Morimoto) in Korea (국내 흰개미(Reticulitermes speratus kyushuensis Morimoto)에 의한 토양의 화학적 특성 변화)

  • Seong, Se Ha;Kim, Keun Ki;Hong, Chang Oh;Park, Hyean Cheal
    • Journal of Environmental Science International
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    • v.26 no.6
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    • pp.789-795
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    • 2017
  • Termites (Isoptera) are classified into approximately 3,106 species. In Korea, only one species has been identified, which is Reticulitermes speratus kyushuensis Morimoto. The termite, a social insect, is known to play an important role in nutrient cycling of the ecosystem, although some species of termites are well-known pests attacking wooden structures or any plant materials. However, there is a lack of research about termites in Korea, including aspects such the taxonomy, physiology, and ecology of termites. This study was carried out to provide valuable basic data on the ecological role of termites in an ecosystem in Korea for the future studies. For the experiments, soil and termite samples were randomly collected from Mt. Hwajang located in Jikdong-ri, Eonyang-eup, Ulju-gun, Korea between October 5 and 30, 2015. Analysis results showed that there were no significant differences in soil chemical properties between the soil samples just after air-drying and one year elapsed without any treatment. The treated soil with termites showed significantly higher than the soil without termite treatment. Chemical properties of total nitrogen, organic matter, available phosphate, pH, Calcium(Ca), Potassium(K) and Magnesium(Mg) in soil treated with termites were $1.11{\pm}0.3gkg^{-1}$, $43.3{\pm}12.4gkg^{-1}$, $27.4{\pm}2.9mgkg^{-1}$, $4.56{\pm}0.2$, $0.82{\pm}0.2cmol_ckg^{-1}$, $3.18{\pm}1.4cmol_ckg^{-1}$, $1.73{\pm}1.1cmol_ckg^{-1}$, respectively. The values of soil property of without termite treatment were $0.56{\pm}0.1gkg^{-1}$, $30.5{\pm}3.1gkg^{-1}$, $24.0{\pm}4.7 mgkg^{-1}$, $4.09{\pm}0.1$, $0.71{\pm}0.2cmol_ckg^{-1}$, $2.88{\pm}1.5cmol_ckg^{-1}$, $1.30{\pm}0.7cmol_ckg^{-1}$, respectively. These results suggest that inhabitation of termites could improve soil chemical properties in an ecosystem.

The Remediation Characteristic of Soil Contaminated with Heavy Metal and Total Petroleum Hydrocarbon (TPH) by Enhanced Electrokinetic with Fenton Oxidation and Soil Flushing Method (펜톤 산화와 토양 세정이 보강된 동전기에 의한 중금속 및 총 석유 탄화수소(TPH)로 오염된 토양의 정화 특성)

  • Seo, Seok-Ju;Na, So-Jeong;Kim, Jung-Hwan;Park, Joo-Yang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.34 no.3
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    • pp.885-893
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    • 2014
  • This research reports the enhanced Electrokinetic (EK) with $H_2O_2$ and sodium dodecyl surfate (SDS), which are commonly used in Fenton oxidation and soil flushing method, in order to remediate soil contaminated with heavy metals and Total Petroleum Hydrocarbons (TPH) simultaneously. In addition, influences of property of soil and concentration of chemical solution were investigated through experiments of different types of soils and varying concentration of chemical reagents. The results indicated, in the experiments using artificially contaminated soil, the highest removal efficiency of heavy metals using 10% $H_2O_2$ and 20mM SDS as electrolytes. However, in the experiments using Yong-San soils (study area), remediation efficiency of heavy metals was decreased because high acid buffering capacity. Through experiment of 20% $H_2O_2$ and 40mM SDS, increased electric current influences the remediation of heavy metals due to decrease in the soil pH. In the experiments of Yong-San soils, the remediation efficiency of TPH was decreased compared with artificially spiked soils because high acid buffering capacity and organic carbon contents. Furthermore, the scavenger effect of SDS influenced TPH oxidation efficiency under the conditions of injected 40mM SDS in the soils. Therefore, the property of soil and concentration of chemical reagents cause the electroosmotic flow, soil pH, remediation efficiency of heavy metals and TPH.

중금속으로 오염된 포화사질토의 저주파대에서의 유전특성

  • 방선영;오명학;김용성;박준범
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.09a
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    • pp.289-292
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    • 2003
  • Laboratory tests were performed to investigate the dielectric property of saturated sands contaminated by heavy metals solution at low frequency. Differences of contamination and the real part of dielectric constant depend on heavy metal concentration was measured at low frequency, 100KHz below. The optimal frequency to develop the detection potentials of monitoring was 1KHz, 10KHz, 100KHz. At this frequency, Heavy metal contamination of saturated sands contamination can be recommended by analysis of complex dielectric constant.

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