• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 창립총회 및 춘계학술발표회
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• pp.84-89
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• 2000

Parametric studies based on laboratory pilot tests were performed to investigate the relationships between electrical resistivity and contaminated soil properties. Three kinds of sandy soils sampled and leachates from a industrial waste landfill were mixed to model the contaminated soils. Electrical resistivity of soils were measured by using a simulated resistivity cone penetrometer probe. In the experiments, the electrical resistivity were observed with changing the water content, void ratio, unit weight, degree of saturation, and concentration of the leachate. The test results show that the electrical resistivity of soils depends largely on the water content and the electrical property of pore water rather than unit weight and types of soils.

• 한국농공학회지
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• 제41권3호
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• pp.91-100
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• 1999

Tow constitutive models for weathered granite soil, Yasufuku's constitutive model with a single yield surface and Lade's constitutive model with two intersectiong yield surface compared in terms of their capabilities to accurately capture the observed behavior of compacted weathered grainite soil for various stress-paths. Both the single surface and the double surface models capture the experimentally observed behavior at a variety of stress-paths with good accuracy. The double surface model may model the observed compacted weathered granite soil behavior with better accuracy for proportational loading with increasing stress, but the single surface model may model dilatancy property with better accuracy for p-constant loading with increasing stress ratio.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.57-59
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• 1998

The headspace method has been acknowledged as a cost-effective and convenient method to analyze volatile organic compounds(VOCs) in soil. The headspace analysis is based on equilibrium partitioning of VOCs among water, air and soil in a closed system. However, the headspace method cannot be applied to soils where most of the VOCs remain sorbed even at high temperature. In this study, it was investigated how the sorption characteristics of VOCs varied with soil with different organic carbon contents and temperature. This study showed that all the VOCs were volatilized, not sorved, only in the soil with 5% organic carbon at 45$^{\circ}C$ or higher. Some fraction of VOCs remained in soil with 8% organic carbon at $65^{\circ}C$ of higher. Most of the VOCs remained sorbed in soil with 12% organic content even at 95$^{\circ}C$. This result suggested that the headspace method can be applied only to soils with little organic carbon content (less than 5%). In this case, 45$^{\circ}C$ seems to be high enough to volatilize all the VOCs from soil. Large particles still showed a significant sorption capacity for VOCs from soil. Large Particles still showed a significant sorption capacity for VOCs despite of their low level of organic carbon content. It was also shown that the organic carbon sorption coefficients (Koc) of VOCs varied with soils with different organic carbon content. This suggests that not only the organic matter content of soil but also the property of the organic matter in soil influence the sorption of VOCs to soil.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권3호
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• pp.28-37
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• 2011

A preliminary study for energy efficient soil heating and contaminant removal using microwave was conducted. Soils sampled from floodplain were heated with microwave oven, and soil heating property and energy efficiency were compared to those heated with electrical furnace. In addition the effects of water, soil organic matter, and contaminated diesel on soil heating with microwave were investigated. Even though the electrical power consumption of electrical furnace and microwave oven were similar, temperature of soil heated with microwave oven was significantly higher than that of soil heated with electrical furnace. The increase of soil moisture content delays the raise of soil temperature during heating it with microwave oven. However, the effects of total petroleum hydrocarbon (TPH) (<10%) in contaminated soil matrix and small amount of soil organic matter (<5%) on the increase of soil temperature by microwave were not significant. Further studies for contaminated soils with different texture using pilot scale microwave reactor are required for application of this technique in the field.

• 한국토양비료학회지
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• 제48권5호
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• pp.436-441
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• 2015

The chemical properties of paddy fields in Gyeonggi province were monitored every 4 years from 1999 to 2015 in order to provide basic information for soil fertility management of paddy fields. In 2015, the soil chemical properties of paddy fields were 5.9 in pH, $23g\;kg^{-1}$ in organic matter (OM), and $84mg\;kg^{-1}$ in available phosphate (Avail. $P_2O_5$). Exchangeable (Exch.) potassium (K), calcium (Ca) and magnesium (Mg) were 0.30, 5.1 and $1.3cmol_ckg^{-1}$, respectively, and available silicate (Avail. $SiO_2$) was $129mg\;kg^{-1}$. In the long-term analysis, the contents of Avail. $SiO_2$, Exch. Ca and pH of paddy soils showed increasing tendency. However, Avail. $P_2O_5$ and Exch. K tended to decrease, and there were no significant changes in the contents of OM and Exch. Mg. Paddy soil within appropriate pH range increased from 44% in 1999 to 76% in 2003, 84% in 2007, 63% in 2011, and 80% in 2015. But soil within appropriate range of Exch. Ca tended to decrease, showing 36% in 1999, 42% in 2003, 38% in 2007, 37% in 2011 and 32% in 2015. In case of Avail. $SiO_2$, soil within appropriate range increased from 14% in 1999 to 17% in 2003, 18% in 2007, 16% in 2011, and 31% in 2015. As a result, paddy fields with less in nutrient level need to be more fertilized based on soil analysis. And the application of silicate fertilizer is strongly recommended to those of paddy fields in need. Also soil management such as the cultivation of green manure crop or application of rice straw will be necessary to increase the organic matter content of paddy soil.

• 한국산림과학회지
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• 제97권6호
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• pp.589-596
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• 2008

우리나라 주요 수종인 낙엽송 임분의 80개 표준지를 대상으로 산림토양의 이화학적 성질 13개 요인에 의하여 지위지수를 추정함으로써 조림예정지, 수종갱신지 등의 미립목지에 대한 낙엽송 임분의 적지를 파악하고자 하였다. 단계별 회귀분석법에 의한 지위지수 추정 결과와 임목생장과 토양의 이화학적 성질과의 관계를 요약하면 다음과 같다. 토양의 이화학적 성질이 지위지수 추정식에 미치는 영향으로 토양산도 및 전질소 인자는 대체적으로 정의상관으로 나타났으며, 유기물 및 유효인산은 부의 관계로 나타났다. 지위지수 추정식에서 인자별 기여도를 분석하기 위하여 표준편회귀계수를 구하여 기여도가 높은 인자를 분석한 바, 낙엽송 임분 토양 A층에서는 염기포화도, 양이온 치환용량, 모래, 치환성 칼슘, 치환성 마그네슘 인자 순으로, 낙엽송 임분 토양 B층에서는 치환성 칼슘, 염기포화도, 전질소, 유효인산, 점토 인자 순으로 나타났다. 한편 낙엽송 임분에서 토양 인자별 A, B층에서 공통적으로 기여도가 높은 인자는 치환성 칼슘과 염기포화도로 주로 나타났다. 이러한 연구결과는 미립목지에서 낙엽송림의 적지를 판별하는데 그 활용가치 및 기대효과가 높을 것이라 사료된다.

• 한국토양비료학회지
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• 제47권6호
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• pp.412-417
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• 2014

Soil properties and yields of red been were investigated to establish soil suitability of Korean adzuki bean at 166 farms in Korea. The soil morphological and physical properties were investigated by 1:5,000 scale average yield of 2~3 years. The impact factors to the adzuki bean yields and soil properties were selected based on standard error of each factor. The yields of adzuki bean showed the greatest values when the morphology was alluvial plains, the drainage was well or moderately well, the slope was 2~7%, the texture was fine loamy, the gravel content was less than 15% and the available soil depth was more than 100 cm. Contribution factors of soil properties to the yields were 0.18 of morphology, 0.18 of drainage level, 0.23 of slope, 0.20 of texture, 0.11 of gravel content and 0.10 of available soil depth, respectively. Soil suitability levels were set as the best suitable land if score was greater than 90, suitable land if score ranged from 89 to 85, the possible land if the score ranged from 79 to 84 and low productive land if score was less than 78. According to the criteria 37.5% of the production area was the best suitable land, 29.4% was suitable land, 22.3% was possible land and 10.8% was low productive land. The best and suitable lands were total of 66.9% in Gyeongju, Gyeosangbuk-do.

• 한국토양비료학회지
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• 제47권6호
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• pp.553-557
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• 2014

The steady increase in livestock industry has greatly required the stable production of food and forage crops. As an alternative, rice-forage cropping system has been attempted in several southern areas. The present study was performed to understand whether an application of cattle-manure compost affects soil chemical properties and crop productivity in rice-forage cropping system, rice ${\rightarrow}$ summer oat ${\rightarrow}$ rye, in Jangheong county, south Jeolla province from 2013 to 2014. Treatments was composed of control (no compost), CM1 (compost application before rice transplanting), and CM2 (two-times compost application, before rice transplanting and after rice harvest), and inorganic fertilizers (N, P, and K) were equally dressed in all plots. Yields of rice were not significantly different between treatments, however, oat production was 1.25-fold higher in CM1 and CM2. Nutrient uptake amounts of rye were higher in CM2 than CM1 and control. Total nitrogen in soil was maintained stable level during crop cultivation. And soil organic matter contents in all treatments were increased by crop residue. Available P_2O_5$ and exchangeable K were increased by cattle manure application. Therefore, it suggested that the amount of nutrient by forage crop residue should be considered in rice-forage multiple cultivation.

• 한국토양비료학회지
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• 제46권6호
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• pp.542-548
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• 2013

Soil properties and yields of liriopis platyphylla were investigated to establish soil suitability of Korean liriopis platyphylla at 116 farms in Korea. Morphological and physical properties of the soils were investigated along with the average yield of 2~3 years. The impact factors of soil properties to the yield of liriopis platyphylla were selected based on standard error of each factor. The yields of liriopis platyphylla showed the greatest values when the morphology was alluvial plains, when the drainage was well or moderately well, when the slope was 0-2%, the texture was coarse loamy, when the gravel content was less than 15% and when the available soil depth was more than 100 cm. Contribution factors of soil properties to the yields were 0.15 by morphology, 0.15 by drainage level, 0.13 by slope, 0.18 by texture, 0.16 by gravel content and 0.23 by available soil depth, respectively. Soil suitability classes were set as follows; the best suitable land if score was greater than 92, suitable land if score ranged from 91 to 86, the possible land if the score ranged from 85 to 83, and low productive land if score was less than 82. According to the criteria, 17.8% of the production area was the best suitable land, 43.1% was suitable land, 17.3% was possible land, and 21.8% was low productive land. The sum of both the best and suitable lands were 60.9% of the farm area of Miryang in Gyeongsangnam-do.

• 한국환경과학회지
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• 제19권2호
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• pp.217-227
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• 2010

This paper was studied $CO_2$ respiration rate with physicochemical properties of soils at wetland, paddy field and forest in Nongju-ri, Haeryong-myeon, Suncheon city, Jeollanam-do. Soil temperature and $CO_2$ respiration rate were measured at the field, and soil pH, moisture and soil organic carbon were analyzed in laboratory. Field monitoring was conducted at 6 points (W3, W7, W13, W17, W23, W27) for wetland, 3 points (P1, P2, P3) for paddy field and 3 points (F1, F2, F3) for forest in 10 January 2009. $CO_2$ concentrations in chamber were measured 352~382 ppm for wetland, 364~382 ppm for paddy field and 379~390 ppm for forest, and the average values were 370 ppm, 370 ppm and 385 ppm, respectively. $CO_2$ respiration rates of soils were measured $-73{\sim}44\;mg/m^2/hr$ for wetland, $-74{\sim}24\;mg/m^2/hr$ for paddy field and $-55{\sim}106\;mg/m^2/hr$ for forest, and the average values were $-8\;mg/m^2/hr$, $-25\;mg/m^2/hr$ and $38\;mg/m^2/hr$. $CO_2$ was uptake from air to soil in wetland and paddy field, but it was emission from soil to air in forest. $CO_2$ respiration rate function in uptake condition increased exponential and linear as soil temperature and soil organic carbon. But, it in emission condition decreased linear as soil temperature and soil organic carbon. $CO_2$ respiration rate function in wetland decreased linear as soil moisture, but its in paddy and forest increased linear as soil moisture. $CO_2$ respiration rate function in all sites increased linear as soil pH, and increasing rate at forest was highest.