• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.455-457
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• 2001

Grounding resistance is the basic performance indicator of grounding electrodes and the resistance has been calculated by simple equations, which is based on the assumption of uniform soil model. In this paper, tower grounding resistance is calculated assuming horizontally 2 layered soil model using finite element analysis method. A simple grouding design graph has been resulted from the calculation results.

• 한국토양비료학회지
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• 제45권5호
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• pp.792-797
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• 2012

경남지역 논토양의 글로말린 함량과 미생물 특성과의 관계를 분석하기 위하여 2011년에 20개소를 선정하여 분석한 결과는 다음과 같다. 토양 글로말린 함량은 토양 유기물 함량 (r=0.595, p<0.01) 및 탈수소효소 활성 (r=0.663, p<0.01)과 정의상관 관계를 나타냈다. 또한, 글로말린 함량은 미생물 생체 탄소 함량 (r=0.710, p<0.001) 및 총 세균군집 (r=0.616, p<0.01)과 정의상관을 보였다. 그리고 글로말린 함량은 그람음성 세균의 군집 (r=0.561, p<0.05) 및 cy19:0/18:$1{\omega}7c$ (r=0.487, p<0.05)와 정의상관 관계를 나타냈다. 따라서 논토양에서 글로말린 함량은 지속가능한 친환경농업을 위해 토양 건강성의 지표로 활용할 수 있을 것으로 생각된다.

• 한국토양비료학회지
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• 제46권1호
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• pp.32-39
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• 2013

The relationship between relative water contents of lettuce leaves and biochemical activities in lettuce was examined in this study to explore an adaptation response of lettuce to water stress from soils. Soil water contents and relative water contents of leaves were positively related to show $R^2$=0.8728. Hydrogen peroxide contents of leaves rapidly increased with reduction of soil water content, whereas soluble protein contents and dry matters rapidly decreased. And chlorophyll a and b contents of leaves decreased with increase in carotenoid content. Furthermore, the activities of ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), and dehydroascorbate reductase (DHAR) increased dramatically, and mRNA transcript levels of APX, MDHAR and DHAR also increased. Relationship of relative water content of lettuce leaves to hydrogen peroxide, to ascorbate peroxidase activity, to dehydroascorbate reductase activity, and to monodehydroascorbate reductase activity was shown to be positively correlated. It is highly plausible from this study that these enzyme activities could be developed as an indicator of water states in soils.

• 한국환경농학회지
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• 제24권3호
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• pp.303-313
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• 2005

Agricultural environmental indicators (AEIs) are useful tool for evaluating environmental performance induced by agri-environmental policy measures. General and specific criteria have been set to assess the linkages between policy measures and environmental states. In addition, a number of specific AEIs such as nutrient balance indicators and farm management indicators have been posit to review environmental performance associated with agri-environmental policy measures. The proposed environmental subjects encompass soil quality, qualities of underground and surface water, water resource preservation, species and genetic diversity, diversity for wildlife habitats, and agricultural landscapes. The developed AEIs may contribute to establishment or adjustment of environmental targets and ex-ante or ex-post evaluation for environmental performance associated with policy measures. In addition, the AEIs may be useful to consider introduction of new agri-environmental measures and enhance policy efficiency by assessing environmental performance, considering specific locality, and harmonizing support measures.

• 한국환경보건학회지
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• 제22권4호
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• pp.109-121
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• 1996

It was intended to investigate the effect of the microbiological kitchen hygiene such as dishclothes and scrubbers. The 8indicator organisms (standard plate counts, coliform, heterotroph, enterococcus, staphylococcus, heat-stable bacteria, psychrotroph, Pseudomonas aeruginosa) were detected highly in dishwaters, dishcloth and scrubber. Coliform and Staphylococcus aureus were appeared on dishcloth dominantly than the scrubber, and the scrubbers were intruded by hetrotrophs and psychrotrophs numerously than dishclothes. The germ-resistant sponge inhibited the growth of the most of test strain, and appeared the about 100% reduction rate after 24 hr, but did not affect Pseudomonas aeruginosa and P. fragi so typically after 24 hr. The anti-microorganism durability of germ-resistant sponge, treated with food soil, was maintained by 10 days, the early stage strain density was founded in 20 days, and the strains grew after 30 days.

• 한국토양비료학회지
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• 제45권4호
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• pp.551-554
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• 2012

The present laboratory investigation was conducted to assess the effect of heavy metals on carbon mineralization. Soil was treated with three concentrations (50, 100 and $150{\mu}mol\;g^{-1}$ soil) of two heavy metals (Cd and Zn) in a factorial combination of treatments replicated four times. Determination of carbon mineralization was carried out at 3, 7, 14, 21, 28, 42 and 56 days after metal treatments.. The amount of $CO_2$-C released from heavy metal treated soils was found to be decreased at an increasing rate during the first 28 days, followed by slow release as incubation progressed. The total amounts of $CO_2$-C released were 448, 382 and $348mg\;kg^{-1}$ soil respectively for soils treated with 50, 100 and $150{\mu}mol\;g^{-1}$ soil of Zn. The corresponding figures for Cd treated soils were 406, 354 and $282mg\;kg^{-1}$ soil implying that dose-dependent reduction in cumulative $CO_2$-C released from soils. The inhibition of carbon mineralization was found to be high in Cd treated soils than that of Zn treated. Therefore, tolerance and adaptation of the microbial community is likely to be related to the concentration and the type of metal. According to the results, carbon mineralization can be considered as possible indicator of soil pollution by means of heavy metals.

• 한국산림과학회지
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• 제98권2호
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• pp.170-177
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• 2009

There are remarkable differences in growth and morphological characters of roots between mountain and field cultivated Panax ginseng. Growth of root in mountain cultivated ginseng was much slower than that of field cultivated ginseng. However, the factor affecting the retarded growth in mountain ginseng was not known. Soil analysis revealed that phosphorus (P) content of mountain soil was exceptionally low at least ten-fold lower compared to that of field soil. Thus, we suggest that low availability of P in mountain soil may be one of the limiting factors for growth of ginseng in mountain soil environment. We had monitored the growth of ginseng plants after one and three years of phosphate fertilizer application. Three kinds of phosphate fertilizers: fused magnesium phosphate, fused superphosphate, and single superphosphate were applied to mountain soil. Application of phosphate fertilizers increased the fresh-, dry weight, and diameter of ginseng roots and resulted in increased P accumulation in roots. These results demonstrate that slow growth of ginseng in mountain soil environment might be attributed to the low P content in mountain soil. Thus, analysis of P amount in mountain soil will be a good indicator for the selection of suitable site the ginseng cultivation in forest.

• 한국토양비료학회지
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• 제49권3호
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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.

• 한국토양비료학회지
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• 제37권6호
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• pp.378-382
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• 2004

Soil pH is an important indicator for soil reactions and crop growth. pH buffer capacity and lime requirements are necessary to comprehend and manage soils well. The characteristics related with soil pH were analyzed and 5 field trials were conducted to elucidate pH buffer capacity of soil and lime requirements and liming factor for Korean acid soils. Soil minerals were analyzed for the soil of 2 years after treating $CaCO_3$ using X-ray diffraction. The amount of neutralized $H^+$ was regarded as the exchangeable aluminium overcoming ${\Delta}pH$, because pH buffer capacity of soil depended on exchangeable aluminium. Lime requirement was somewhat similar to the KCl exchangeable aluminium and it was also affected by the exchangeable cation by added lime. X-ray diffraction analyses revealed that an aluminium dissociation from Korean acid soils was equilibrated with kaolin minerals and changed into anorthite ($CaAl_2Si_2O_8$) by neutralizing with $CaCO_3$. Neutralizing process was composed of changing process of $Al^{3+}$ into $H^+$ and $Al(OH)_4{^-}$ ionic species and of neutralizing $H^+$ by, the amount of which was lime requirement. The fact that anorthite dissociates an aluminium ion higher than kaolinite does enabled to consider a liming factor (LF) the content of exchangeable cation and ${\Delta}pH$, $LF=1.5+0.2{\times}{\sum} Cations{\times}{\Delta}pH$.

• 한국미생물·생명공학회지
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• 제40권1호
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• pp.30-38
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• 2012

두 종의 Bacillus와 한 종의 Pseudomonas로 구성된 컨소시엄 미생물제제를 고추 경작지에 첨가하였을 때 경작지 토양의 미생물 다양성 변화를 조사하기 위해 건전한 토양의 지표가 되는 질소순환관여 미생물과 근권토양 내 섬유소 분해기능, 인산가용화기능과 urea 가수분해기능을 가지는 기능성미생물의 활성과 밀도를 측정하였다. 고추 경작지 토양에 컨소시엄 PGPR 미생물인 B. subtilis AH18, B. licheniformis K11과 P. fluorescens 2112의 컨소시엄 미생물제제를 처리하여 토양미생물의 다양성에 변화를 측정하여 컨소시엄 미생물제제의 처리에 의한 근권토양 미생물의 다양성 변화와 고추의 생육에 미치는 영향을 분석하였다. 컨소시엄 미생물제제 처리구의 경우 Actinomyces spp., Trichoderma spp., 광합성세균과 Azotobacter spp.가 다른 처리구에 비하여 1.7-5배 이상 높았으며, 질소 순환에 관여하는 미생물은 1.4-4배 증가되었다. 또한 기능성 미생물의 다양성도 화학제제나 물처리구와 비교하였을 때 1.3-3배 증가하였다. 건고추 수확량은 컨소시엄 미생물제제를 처리하였을 경우 대조구나 화학제제를 처리하였을 때보다 15%이상 수확량이 증대되었다. 따라서 PGPR 컨소시엄 미생물제제의 처리로 인해 고추 경작지 토양의 근권미생물 다양성과 작물의 생산성에 긍정적인 영향을 주는 것으로 생각된다. 추후 메타지노믹스를 활용하여 미생물 다양성 변화를 추가적으로 확인할 예정이다.