• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.214-223
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• 2006

For better management of micronutrients in crop cultivation, the availability of micronutrients in the soils must be updated and evaluated as a first step. This study was conducted to investigate the distribution of micronutrients in soils of plastic film houses. Total 396 soil samples were collected from the plastic film houses of various crops in Yeongnam province (strawberry, 96; red pepper, 66; tomato, 74; oriental melon, 97; cucumber, 63). Total and available contents of B, Cu, Zn, Fe, and Mn in the soils were determined. Available B was extracted with hot water and available Cu, Zn, Fe, and Mn were extracted with 0.1 N HCl. Mean values of total contents of B, Cu, Zn, Fe, and Mn in the plastic film house soils were 25, 32, 74, 21,316, and $420mg\;kg^{-1}$, respectively. Total contents of micronutrients in the plastic film house soils were similar to those found in the open fields nearby, while they were different among the locations investigated. Mean contents extractable B, Cu, and Zn in the plastic film house soils were 2.1, 7.5, and $35mg\;kg^{-1}$, respectively. The contents of extractable B, Cu, and Zn in the plastic film house soils were higher than those found in the open fields nearby with exceptions of B in soils of strawberry and Cu in soils of red pepper and oriental melon. However, mean contents of extractable Fe and Mn in the plastic film house soils were 156 and $146mg\;kg^{-1}$, respectively, and the mean content of extractable Fe was much lower than that found in open fields nearby. The contents of extractable Zn, Fe, and Mn were higher than the sufficient levels for the crop requirements in most of the plastic film house soils investigated. Contents of extractable Cu in most soils of strawberry, tomato and cucumber cultivations were higher than the sufficient level. However, extractable Cu contents were below the sufficient level in about 30% of investigated soils of red pepper and oriental melon cultivation. Soils containing higher contents of extractable B than the sufficient level were relatively fewer in comparison to the other micronutrients.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.145-152
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• 2002

The composition of primary minerals in the rocks and secondary minerals of clay fractions of the soil developed on the cinder cones in the foot of Halla Mt., Jeju Island was investigated. The effects of parent materials on the physico-chemical properties and mineralogical characteristics were evaluated by XRD, DTA with the chemical composition of $H^+$ saturated clays. The main rock-forming minerals of a residual cinder cones were plagioclase with subsidiary minerals of hematite, gibbsite and quartz in the red cinder cone and of augite, quartz, feldspars and olivine in black cinder cone. It is demonstrated that ignition loss and sesquioxides content were higher in the red cinder soil than black cinder, which was resulted in the intermittent eruption of volcanic activity. For the chemical analysis of whole soils, $SiO_2/Al_2O_3$ ratio was increased from 2 to 3, but Ignition loss is decreased and $K_2O$ content are very low with increasing the soil depth in regard to the composition and kinds of clay minerals. No clay formation from micas mineral were in volcanic ashes. Dominant clay minerals of the cinder cone soils as a black and red cinder cone soil were allophane with some quartz and feldspars, while vermiculite, illite, kaolin were coexisted as a subsidiary minerals. But the red cinder cones soils had more hematite and gibbsite of the clay fractions than the black soils with magnetite. The exothermic pick of DTA at about $660^{\circ}C$ for cinder cone soils might be corresponded the oxidation magnetite to hematite reation. With regarding to the compositions of mineral detected by X-ray diffractogram and the properties of minerals by D.T.A thermogram, the dominant clay mineral was allophane of the cinder cone soils with some ferrous compounds, red colour of the cinder cone soils which are originated in hematite.

• Journal of the Speleological Society of Korea
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• no.62
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• pp.1-9
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• 2004

The main purpose of this paper is to clarify the relationship between the development of the Uro cave and the characteristics of the landform development. The mountain systems of the study area are north-western part. central part and south-eastern part. The third order streams are developed, and the bifurcation ratios are 7.0 and 4.0. The drainage density and the networks of the streams are not well developed in this area. The rocks of this area are sedimentary rocks, metamorphic rocks and Igneous rocks. The soils are lithosol, and red-brownish soils.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.3
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• pp.419-428
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• 2011

Recycling as a stabilizer of industrial by-product can be terms of the proper handling of industrial by-product and positive side in terms of recycling of waste. This study was performed to evaluate has the possibility as stabilizer by primary processing Pre-Red Mud and Bio-Solids which are generated as waste in soils contaminated with heavy metals and compared the efficiency with steel slug being applied in an existing site. In evaluation of the arsenic-fixing ability of stabilizer in batch test, Bio-Solids have the similar arsenic-fixing ability with Pre-Red Mud, which shows 17% h igher arsenic-fixing ability than PS Ball. Since the stabilization periods using Bio-Solids and Pre-Red Mud are faster than the PS Ball, they seems to be better stabilizer than PS Ball to decrease the leaching of arsenic in contaiminated soil.

• Journal of the Korean Geographical Society
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• v.18
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• pp.1-12
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• 1978

이 글에서는 다음의 내용을 다루었다. 1. 토양교질물의 화학분석 결과 및 고찰 2. 토양생성화 작용과 규반 비.규철반비와의 관계

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.1
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• pp.21-30
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• 2017

The study was performed to determine effective soil depth with crop type. Lysimeters, filled with three types of soils (sandy loam, loam and clay loam), were used. Effective soil depths for 25 cm, 50 cm, 75 cm, and 100 cm were considered for each soil. Six crops were investigated for plant height and yield, and rooting depths: Chinese cabbage, maize, lettuce, potato, red pepper, and soybean. Experiment was conducted at the National Institute of Agricultural Sciences in Suwon from 2012 to 2014. Effective rooting depth including 70% of root ranged from 19 cm to 29 cm for Chinese cabbage, from 24 cm to 38 cm for maize, from 17 cm to 24 cm for lettuce, from 27 cm to 32 cm for soybean, and around 50 cm and 30 cm for potato and red pepper. The maximum depth was 60 cm for soybean, 50 cm for Chinese cabbage, lettuce, and potato, and 75 cm for maize and red pepper. Each crop showed high yield in the treatment with soil depth over maximum rooting depth under all soils.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1994.06a
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• pp.50-61
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• 1994

Biological control of important fungal diseases such as Phytophthora blight of red pepper, gary mold rot of vegetables, and powdery mildew of many crops was attempted using an antagonistic bacterium, Bacillus sp. AC-1 in greenhouses and fields. The antagonistic bacterium isolated from the rhizosphere soils of healthy red pepper plant was very effective in the inhibition of mycelial growth of plant pathogenic fungi in vitro including Phytophthora capsici, Rhizoctonia solani, Pyricularia oryzae, Botrytis cinerea, Valsa mali, Fusarium oxysporum, Pythium ultimum, Alternari mali, Helminthosporium oryzae, and Colletotrichum gloeosporioides. Culture filtrate of antagonistic Bacillus sp. AC-1 applied to pot soils infested with Phytophthora capsici suppressed the disease occurrence better than metalaxyl application did until 37 days after treatment in greenhouse tests. Treatments of the bacterial suspension on red pepper plants also reduced the incidence of Phytophthora blight in greenhouse tests. In farmers' commercial production fields, however, the controlling efficacy of the antagonistic bacteria was variable depending on field locations. Gray mold rot of chinese chives and lettuce caused by Botrytis cinerea was also controlled effectively in field tests by the application of Bacillus sp. AC-1 with control values of 79.7% and 72.8%, respectively. Spraying of the bacterial suspension inhibited development of powdery mildew of many crops such as cucumber, tobacco, melon, and rose effectively in greenhouse and field tests. The control efficacy of the bacterial suspension was almost same as that of Fenarimol used as a chemical standard. Further experiments for developing a commercial product from the antagonistic bacteria and for elucidating antagonistic mechanism against plant pathogenic fungi are in progress.

• Applied Biological Chemistry
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• v.15 no.2
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• pp.143-162
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• 1972

Based on the concentration of $^{40}K$ naturally occurring radioisotope of potassium, a method for the determination of total potassium in soils and plants was developed. The method was extended to evaluate the potassium supplying power of soils by taking the ratio of exchangeable potassium to total potassium $(K_{ex}/K_t)$, termed the potassium buffering capacity. Using this as index, it was observed that the release of potassium from soil fellows the from order reaction. A linear relationship was found between the potassium buffering capacity and the release constant of potassium or mica content of the clay. Similarly the potassium buffering capacity was also closely correlated with total uptake of potassium by rice plant. Hence it is concluded that the method for determining of the potassium buffering capacity could be veil applied to characterize the potassium availability of soils. The method for the determination of potassium is characterized by (1) The efficient measurement of the weak beta activity emissions from the samples, (2) identification of $^{40}K$, (3) calculation of total potassium content using the proportional constant of $^{40}K$ of samples to that of the standard. Difference in the potassium supplying power of soils due to soil types was also evaluated with the use of this technique. The degree of the potassium supplying power was in the order of soil types as red-yellow podzolic and lateric soils, basaltic materials(Rvd)> low-humic gley and alluvial soils, alluvial plains and food plains(Apa)> low-humic gley soils, nearly level to sloping local alluvial plains and slopes(Afb)> low-humic gley and alluvial soils, fluvio-marine plains (Fma).

• Korean Journal of Pharmacognosy
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• v.7 no.1
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• pp.59-61
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• 1976

The purpose of the study is to investigate the possibility of cutting of Eucommia ulmoides $O_{LIV}.$ (Eucomiaceae) by using various soils in Korea. Four different kinds of soil, such as sand, red cray, red cray plus sand and Masa soil, were used in the investigation. It was found that total length, number and rate of rooting were most prominent in the cutting cultivated in Masa soil.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.280-285
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• 1994

This study was conducted to investigate the effects of acid deposition on forest soil, major five Korean forest soils(Brown, Dark red, Gray brown, Red and Yellow, and Volcanic ash forest soils) The samples were subjected to receive 1200mm($100mm{\times}12$ times) of artificial acid rain adjusted to pH5.6, 4.0, 3.0 and 2.0. The results obtained of major importance are summarized as follow ; 1. Ca appeared mostly affected at pH treatment of 2.0, while less affected by other pH treatments. Leaching of Ca rapidly increased with increasing of artificial acid rain acidity and application times in Dark red forest soil. 2. In the cases of Mg, K and Na, they showed gradual increase with the addition of artificial acid rain. Mg and Na losses showed similar leaching patterns, but they didn't show difference among the five forest soils. 3. Exchangeable canon concentrations in the soil leachates, which looked slightly different among the five forest soils, were the highest in pH2.0 treatment. Hydrogen ion comsumption capability by exchangeable canon was the highest in Dark red forest soil followed by Volcanic ash, Red and Yellow, Gray brown and Brown forest soils when artificial acid rain were treated.