• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.483-487
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• 2006

본 연구는 비점오염원에 의한 수질오염현상을 억제하기 위한 수변지역의 관리기법 중 하나인 식생여과대를 효과적으로 설치하기 위하여 식생에 의한 오염물질의 저감능력을 파악하고 효율적 설치방안을 모색하기 위하여 수행되었다. 연구결과 T-N과 T-P의 깊이별 오염물질 저감효과는 나대지에서 표면유출이 각각 17.6%, -23.9%, 단면유출이 각각 51.7%, 91.0%, 하부유출이 각각 38.4%, 89.3%인 것으로 나타나 표면층을 통한 유출보다는 토양층에 침투될수록 오염물질의 저감효과가 높아지는 것으로 나타났다. 잔디로 표면층을 식재한 실험에서는 표면, 단면, 하부유출에서의 T-N이 각각 16.0%, 57.1%, 38.4%의 오염물질 저감효과를 보였고, T-P의 저감효과는 각각 -9.7%, 83.6%, 88.8%인 것으로 조사되었다. 또한 돌미나리로 표면층을 식재한 실험에서는 표면, 단면, 하부유출에서의 T-N 처리효율이 각각 -2.6%, 62.1%, 71.2%로 나타났으며, T-P는 각각 -7.2%, 94.5%, 84.5%인 것으로 조사되었다. 결론적으로 식생을 한 경우 전체적으로 오염물질의 저감효율이 비교적 안정되게 유지되는 것으로 나타났으나, T-P의 표면층을 제외하면 전체적인 저감효과에 크게 영향을 미치지 않은 것으로 판단된다. 그러나 일반적으로 알려져 있는 식생에 따른 오염물 저감효과에 대한 순기능 즉 토양입자의 침식방지, 토양용액의 저류작용 및 공극확대에 따른 침투능력 증대, 토성의 개량 등과 같은 기능을 무시할 수 없으므로 오염저감효과를 극대화하기 위해서는 처리대상이 되는 하천유역의 자생적 식생을 보다 효과적으로 활용할 수 있는 방안마련이 비용적 측면이나 생태 보존적 측면에서 유리할 것으로 판단된다.one)을 설치하는 대책이 필요하다. 저수지 관리를 효과적으로 수행하기 위해서는 저수지 내부의 탁도 거동을 정확히 예측할 수 있어야 한다. 따라서 추후 동수역학 및 열역학에 기초한 3차원 수치모형 연구와 성층흐름에 정밀한 밀도류 실험연구 및 이에 대한 적용이 필요할 것으로 판단된다.함으로써 정보의 질적보장과 정보전환의 표준화방안을 제시하는 정보분석시스템이다.이용, 수자원의 지속적 확보기술의 특성에 따른 4개의 평가기준과 26개의 평가속성으로 이루어진 2단계 기술가치평가 모형을 구축하였으며 2개의 개별기술에 대한 시범적용을 실행하였다.하는 것으로 추정되었다.면으로의 월류량을 산정하고 유입된 지표유량에 대해서 배수시스템에서의 흐름해석을 수행하였다. 그리고, 침수해석을 위해서는 2차원 침수해석을 위한 DEM기반 침수해석모형을 개발하였고, 건물의 영향을 고려할 수 있도록 구성하였다. 본 연구결과 지표류 유출 해석의 물리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다. 있을 것으로 판단되었다.4일간의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.571-576
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• 1996

The geological and hydrological survey was carried out in Hyuseok-dong landslide area(10 ha), Youngchoon-myeon, Danyang-gun, Choongcheongbuk-do. The results showed that the bed rocks in this area consisted of shale, sandstone and limestone, and the piles of stones debris were also scattered around the hill above the study area. Soil texture was sandy loam, and bulk density of the soil in the lower part of the area was higher than that of the upper part, but void ratio of the soil in the lower part was lower than that of the upper part. Subsurface water was springing out to the surface in many places in this area. In this area, the storms over 70mm/day were frequent during the summer period from June through September. It was concluded that the occurrence of landslide had a close relationship with the geological characteristics, hydrological conditions and the rainfall distribution.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.304-304
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• 2011

최근 도시화에 따른 인구증가와 더불어 도로포장 등 불투수면적의 증가로 인하여 우기시 빗물 침투가 차단되어 도심의 지하수위가 저하되며 토양의 건토화, 열섬현상 등의 문제가 발생하게 되었다. 이러한 문제점에 착안하여 본 연구에서는 투수효과를 최대한 고려할 수 있는 고강도의 친환경 콘크리트 블록(에크스톤 바이오 블록; ECOSTONE-BIO BLOCK)을 개발하였으며 기존 콘크리트 블록의 자연적 빗물침투 억제의 문제점을 일부 개선하였다. 본 블록은 캡슐공법을 사용하여, 공극률은 높이면서(투수성 향상), 강도와 내구성이 유지됨은 물론 캡슐안에 황토성분을 첨가하여, 바이오적인 기능 및 재생골재를 이용한 친환경적 제품으로 투수성, 내구성, 기능성을 극대화 시켰다. 또한 제품표면은 천연 백색돌맹이, 흑색돌맹이의 배합으로 자연석재 느낌을 구현하였으며, 쇼트블라스트 및 커링 표면공정으로 미끄럼저항지수를 조절할 수 있어, 기존 콘크리트 보도블록에 비해 투수율, 내구성, 기능성, 안전성이 우수하여, 안전한 보행환경이 가능한 것으로 분석되었다. 마지막으로, 주변 환경과 잘 어울리도록 디자인된 바이오기능성 친환경 블록으로 도심지역 시공시 투수효과에 따른 지하수고갈방지 및 침수피해에 도움을 주리라 사료된다.

• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.9-24
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• 1997

Surfactant-aided in situ soil flushing has been proposed as an alternative for the expensive and time consuming 'pump and treat' technology in remediation of contaminated soil and groundwater Injected surfactants can effectively solubilize contaminants sorbed to the soil matrix or nonaqueous phase liquids(NAPLs) in residual saturation. The contaminants solubilized in groundwater are recovered and treated further. The theoretical background of the technology and the results of the field operations, mostly in the US. were summarized. In addition, the factors crucial to the successful application of the technology were discussed. Cost analyses and technical limitations in current applications were also discussed. In conclusion, it is likely that in situ surfactant flushing become a viable option for soil remediation in limited cases. Currently, further advances with respect to operation cost and to treatment efficiency are required for more extensive application of the technology. However, the current trends in soil remediation, specially the growing emphasis on risk based corrective action and natural attenuation, will increase the competitiveness of the technology. For example, removal of easily washable contaminants by short term soil flushing followed by long term monitoring and natural attenuation can greatly reduce the operation cost and time.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.4
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• pp.241-248
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• 1993

An experiment was conducted in 1990~1991 to study the effects of various soil amelioration on the soil productivity and machine workability at tidal land paddy field of Kyewhado Substation, Homam Crop Experiment Station. The soil, Munpo Series(fine sandy loam, Typic Fluvaquents) was treated with gipsum, rice straw, rice straw compost and foreign soil(at 20cm depth) after deep ploughing. The results are surmerized as follows. 1. Sand and clay were slightly increased, while silt was slightly decreased in the rice straw and compost plots. The soil texture was changed from loam to sand loam by the addition of foreign soil 2. Soil bulk density and porosity was decreased in the rice straw, compost and foreign soil addition plots. 3. Cone penetration resistance was $12.5kg/cm^2$ at 10cm of soil depth before experiment and $12.5kg/cm^2$ at 20cm of soil depth after experiment except control, and the root zone was expended down to 20cm. 4. Soil salt content before experiment was 0.46 and 0.48% for surface soil(10cm) and subsoil(20cm), respectively ; The salt content of ameliorated plot was 0.26~0.32% and 0.16~0.31%, respectively, indicating good leaching of soil salt by the soil improvements. 5. The yields of rice in different treatments were in the order of the foreign soil addition > compost > gypsum > rice straw > control.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.69 no.1
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• pp.34-48
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• 2024

The objective of this study was to evaluate the safety of biodegradable mulching films in soybean (Glycine max) cultivation by measuring their effects on crop growth and yield, film decomposition and soil chemical and physical properties. In 2022 and 2023, plant height, branch number, chlorophyll contents, yield components, and yield of soybean did not vary significantly in areas using PE films and biodegradable mulching films. The light transmission rate of the biodegradable mulching films ranged from 6.4 to 15.8% when measured 112 days after soybean transplanting, and was higher, on average, in 2023 than in 2022. In both years, degradation of the biodegradable mulching films began 20 days after soybean transplantation and increased over time. In addition, remains of biodegradable mulching films were present in fields at soybean harvest and remained until 50 days after harvest. Decomposition rates of the biodegradable mulching films at 112 days after soybean transplanting ranged from 9.8 to 26.7% in 2022 and 13 to 36% in 2023. Although soil pH and EC varied based on the year and timing of measurements, there was no significant difference between areas that used biodegradable mulching films and PE films. Soil organic matter, nitrate and exchangeable cation contents such as Ca, Mg, and K were not significantly different in areas that used both PE films and biodegradable films. However, significantly higher levels of available phosphoric acid content were measured in areas that used biodegradable mulch films E, S, and T. Regardless of which films were used, there were no significant differences in the soil's physical properties. In 2022 and 2023, there was no difference between areas that used biodegradable mulch films and PE films. However, soil temperature in mulched areas was 2℃ higher and soil moisture was 5-15% higher than in non-mulched areas. Barley growth was not affected by being planted in soil that had been used for soybean cultivation with biodegradable films. Therefore, the biodegradable mulch films used in this study can be used without negatively affecting the growth, yield, and soil environment of soybeans.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.12
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• pp.855-862
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• 2012

Caenorhabditis elegans, a free-living nematode mainly found in the soil pore water, roles the critical function in trophic levels, energy flow, and decomposition in soil ecosystem. C. elegans is commonly used species to test soil toxicity. Recently, they are employed broadly as a test organism in nanotoxicology. In this study, a review of the toxicity of nanomaterials for C. elegans was presented based on SCI (E) papers. The nanotoxicity studies using C. elegans have been reported in 20 instances including the mechanism of toxicity. Most studies used K-medium, S-medium, and NGM (Nematode Growth Medium) plate as an exposure medium to test toxicity of nanoparticles. The effects observed include anti aging, phototoxicity, genotoxicity, and dermal effects on C. elegans exposed to nanoparticles. We found that the toxic mechanisms were related with various aspects such as lifespan abnormality, oxidative stress, distribution of particles on inter-organisms, and stress-related gene analysis. C. elegans has advantage to test toxicity of nanoparticles due to various cellular activities, full genome information, and easy observation of transparent body. C. elegans was considered to be a good test species to evaluate the nanotoxicity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.459-463
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• 2001

Changes of rice yield and soil physicochemical properties of the dry-seeded rice-barley double cropping system were investigated for 10 years from 1990 to 1999. Generally, seedling stand was more unstable in the rice-barley cropping system regardless of barley straw addition or removal than in the rice single cultivation as indicated by higher standard deviation of seedling stand across year. Rice yield in rice-barley double cropping cultivation was increased due to barley straw application starting from the second year, recording 2 to 19％ increase (average of 9％ for 10 years) due to higher spikelet number. Protein content and Mg/K equivalent ratio were similiar among the barley straw applied field, rice single crop and barley straw removed plots. Also, amylose content was not significantly different among cropping patterns. Physicochemical properties of soil was improved by applying the barley straw; soil porosity was higher and content of organic matter and cation exchange capacity of Ca increased but those of Mg and K did not differ.

• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.163-170
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• 2008

This experiment was conducted to determine the development of mixed organic fertilizer using photosynthetic bacteria and mass production of mixed microbial compound for the environment-friendly agriculture. Photosynthetic bacteria, Rhodobacter sp. SA16 was isolated from soil collected by plastic film house. The SA16 strain was identified based on 16S rDNA sequence analysis and it is closely related to Rhodobacter sp.(100% similarity). The mixed organic fertilizer using SA16 was made of $N-P_2O_5-K_2O=60-10-20\;g\;kg^{-1}$ with combined soybean cake, sesame cake, powdered blood, fish meal, powdered bones and red-yellow soil. The mixed organic fertilizer 0.45, 0.90 and 1.35 Mg $ha^{-1}$ application in Ihyeon series was treated based on soil testing for lettuce cultivation in plastic film house. These results showed that the yield was increased the 18 and 19%over control by the mixed organic fertilizer application 0.45 and 0.90 Mg $ha^{-1}$, respectively. In the physical properties of the soil, the porosity of mixed organic fertilizer 1.35 Mg $ha^{-1}$ treatment was highest at 58.8%. Our results clearly revealed that the organic fertilizer using Rhodobacter sp. SA16 and mass production of mixed strains could be a useful technology in pursuing environment-friendly agriculture.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.81-88
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• 2001

This experiment was carried out to evaluate the effect of residual food compost application on plant growth and physicochemical properties of soil when residual food compost made from the composting process as part of organic waste recycling was applied in soil as variable rate. The treatments were composed non-fertilizer treatment, control treatment applied with pig compost $20Mg(D.W.)ha^{-1}$, and residual food compost treatments each of applied with 20, 40, 60, $80Mg(D.W.)ha^{-1}$ and were randomized complete block design with three replication. Soil pH after experiment was more increased as more increase application of residual food compost. Other chemical properties of soil including EC were also showed the similar results. The plant growth in treatments applied much of residual food compost at the early growth stage was very damaged and these results were proved at the first growth measurement. Production of the red pepper especially reduced in treatments taken growth demage at the early stage and that of $20Mgha^{-1}$ treatment almost same as control treatment. Bulk density was reduced but porosity was increased according to increase of residual food compost application. Considering the reduction of red pepper production and the demage of growth at the early stage by plenty of salt and water soluble application volume of residual food compost was not permitted over of $30Mgha^{-1}$. Additively, to settle the application volume of residual food compost and to evaluate the plant growth and changes of physicochemical properties of soil, the results taken from continual applying is concluded more important than single application.