• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.3
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• pp.18-24
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• 1999

This study was aimed to develope appropriate soil media for the growth of Rhododendron hybrid $J_{ASANHONG}$ on the artificial ground five types of soil media was tested such as "sandy loam-general soil (T1)", "vermiculite-artificial soil (T5)", "sandy loam 50% + vermiculite 30% + sand 20% (improved of soil 2-T2)", "sandy loam 50% + carbonized rice hust 30% + sand 20% (improved of soil 3-T3)", "sandy loam 50% + humus sawdust 30% + sand 20% (improved of soil 4-T4)". The result of the research are as follows. 1. Among the type of soil media, the sandy loam(T1) soil type gave the worst effects on growth of above ground parts(height, No. of leaf, width of leaf, No. of flowering, dry weight of upper parts) and under ground parts(dry weight of roots). 2. Vermiculite(T5) showed the highest root growth(dry weight of roots). it seemed to be caused high saturated hydraulic conductivity and porosity. As a result, there is much available space for enabling the root spreads. 3. "sandy loam 50% + vermiculite 30% + sand 20%(improved of soil 2-T2)", "sandy loam 50% + carbonized rice hust 30% + sand 20%(improved of soil 3-T3)" showed good effects on growth of above ground parts and under ground parts compared with sandy 10am(T1) 4. "sandy loam 50% + humus sawdust 30% + sand 20% + (improved of soil 4-T4)" showed the highest effects on growth of above ground parts.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.83-91
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• 2006

This research was initiated to enhance the tilth of fine-textured soil for turf growth by incorporation of crumb rubber shredded from used tires. A specific objective was to determine the physical properties of soil mixes amended with different grade and amount of crumb rubber in soils. Two soils and three different grades(3.5, 6.5 and 9.5 mm) of crumb rubber were used. The soils selected were an Arenzville silt loam(coarse-silty, mixed, nonacid, mesic Typic Udifluvents) and a Hosmer silty clay loam(fine-silty, mixed, mesic Typic Fragiudalfs). The amount of crumb rubber mixed in soil ranged from 0 to 0.4 $g{\cdot}g^{-1}$(using 0.05 $g{\cdot}g^{-1}$) increments and 0 as a control. For each treatment, soil cores were constructed following the recommendation by the United States Golf Association Green Section Record. Results indicated that porosity of the mixes decreased as the amount of crumb rubber increased. Regardless of the grade of crumb rubber, mixes with less than 0.15 $g{\cdot}g^{-1}$ of crumb rubber in fine-textured soil could not enhance their macro-porosity and hydraulic conductivity. However, as the amendment increased over 0.15 $g{\cdot}g^{-1}$, the tilth of the mixes had improved significantly macro-porosity, hydraulic conductivity and air permeability, as compared with a control.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.17-22
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• 2009

계절에 따른 토양공극의 수리학적 변화를 파악하기 위해서 설마천 유역의 범륜사 독립사면과 광릉 원두부 소유역의 독립사면을 대상으로 장력침투실험을 실시하였다. 토양수분 확보에 신뢰를 받기위해서 TDR(Time Domain Reflectometry)및 현장에서 토양의 불포화 투수계수 측정이 가능한 장력침투계(Tension infiltrometer)를 이용하였다. 계절에 따른 자료수집을 위해서 2008년 3월 20일 부터 약 6주간격으로 10월 29일까지 5회에서 6회 토양수분 자료 및 토양장력침투 자료를 획득하였다. 획득한 자료를 이용하여 포화 및 불포화 수리전도도, 대공극 유효흐름분율(macropore flow), 대공극 유효부피분율을(effective macroporosity) 나타내었다. 분기별로 자료분석 결과 계절별 특성이 나타남을 알 수 있다. 수리전도도는 3월, 5월, 10월은 유사한 반면 6월과 7월 그리고 9월은 상대적으로 높았다. 이는 여름철에 공극 발달이 활발하다는 것을 의미한다. 선행토양수분은 수리전도도에 영향을 미치는 것으로 나타났다. 대공극의 발달은 삼림과 같은 복잡 경관에서는 강우사상에 따른 토양수분의 공간 분포 및 이송, 유출과정이 물순환에 영향을 미친다. 지형분석을 통한 공극의 흐름특성과 토양수분 유의성에 대하여 논의하였고, 대공극 변화에 밀접한 관계가 있는 식생과 그밖에 계절적으로 발달을 일으키는 요인을 모색 하였다. 본 연구는 계절에 따라 변하는 수리전도도를 기초로 하여 불포화대에서 토양공극의 수리학적 변화와 시공간적으로 침투흐름에 얼마나 영향을 주는가를 보여준다.

• Ecology and Resilient Infrastructure
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• v.4 no.4
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• pp.193-199
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• 2017

In this study, changes of soil properties including soil texture, specific surface area, organic matter content, pH, cation exchange capacity and exchangeable cations content were investigated in response to strong acid or base accident. The properties changed significantly when the soil reacted with 10 M HCl or 1 M NaOH (i.e., when one gram of soil received 50 and 5 mmol of HCl or NaOH), respectively. When the soil reacted with 10 M HCl or 1 M NaOH solution, soil texture changed from sandy loam to loamy sand and specific surface areas decreased from $5.84m^2/g$ to 4.85 and $1.92m^2/g$, respectively. The soil organic matter content was reduced from 3.23% to 0.96 and 0.44%, and the soil pH changed from 5.05 to 2.35 and 10.65, respectively. The cation exchange capacity decreased from 10.27 cmol/kg to 4.52 and 5.60 cmol/kg, respectively. Especially, high concentrations of $Al^{3+}$ or $Na^+$ were observed in acidic or basic spills, respectively, which is likely to cause toxicity to terrestrial organisms. The results suggest that restoration of soil properties, as well as soil remediation, needs to be carried out to maintain the soil function in chemical spill sites.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.170-173
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• 1998

This study was conducted to investigate the effect of municipal sludge application on the change of physico-chemical properties and contents of heavy metals in soils. The application of the sludge resulted in increasing the content of total nitrogen, available phosphate,exchangeable K, Ca, Mg, and the soil porosity and permeability but soil hardness was reduce. It is clear that application of municipal sewage sludge would not due to increase in the heavy metals content in soil because of the lower concentration of heavy metal in the sludge. Totally it is evident that municipal sewage sludge application should play an important role in improving soil physico-chemical properties.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.69-69
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• 2023

격자 기반의 지면모형을 구동하기에 앞서 사용자의 목적에 따른 모델의 정확도와 모델의 구동 시간의 적절한 균형을 이루는 지면 모델의 격자 크기의 설정은 중요하다. 특히, 격자 크기에 따라 화재 모의 결과 영향이 매우 클 수 있지만, 이에 관한 연구들을 거의 이루어지지 않았다. 화재 모의는 탄소 순환뿐만 아니라 물 순환에도 직접적인 영향을 미치기 때문에 이를 위한 적절한 격자 크기 설정은 중요하다. 본 연구에서는 지면모형인 NCAR Community Land Model version 5(CLM 5)-biogeochemistry (BGC) 모형과 2000년부터 2019년의 The Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) 기상자료 이용하여서 지면 모델 격자 크기(1.9°×2.5°, 0.47°×0.63°, 0.25°×0.25°)에 따른 전 지구 규모의 화재 시뮬레이션 결과들을 분석하였다. 연평균 화재면적은 격자 크기가 제일 큰 1.9°×2.5° 격자의 시뮬레이션에서 연평균 450M ha로 가장 작게 나타났으며 격자의 크기가 작아질수록 화재의 크기는 증가하는 것으로 나타났다. 지면 모델의 격자가 작아짐에 따라 토양 입자의 분포가 세분화되고 이에 따라 투수 계수값이 증가하며 높은 토양수분의 분포들을 줄어들고 낮은 토양수분의 분포는 증가함을 확인하였다. 토양수분이 줄어듦에 따라 화재 연소성 정도를 나타내는 변수의 값이 증가하고 이에 따라 화재 발생빈도 및 화재 확산이 증가하여 지면 모델의 화재면적을 더 증가시키는 요인이 됨을 확인하였다. 이 연구를 바탕으로 하여 화재 모의의 불확실성 요소를 이해하고, 격자 크기에 따라 화재 모의 관련 매개변수의 수정이 필요할 것으로 판단된다.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.279-288
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• 2020

Sand dams are formed by installing beams across rivers and filling the secured space with water and a permeable material, such as sand, which stores the water in available pore space. These structures have mainly been reported in Kenya, Africa. This study proposes a sand dam design that improves structural safety and water intake. First, to increase the stability of the concrete wall of the dam, steel barbed wire connections are proposed for construction. Second, by using geotextile fabrics, evaporation may be reduced from 45% to 8%, and horizontal permeable discharge could be reduced markedly, therefore improving water storage capabilities. In addition, the water intake increased by ~2.4 times that of the previous design. Third, filtration efficiency is improved by selecting a sedimentary site for improved water quality. Finally, the installation of a tensiometer is suggested for monitoring the sand dam.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.727-733
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• 2009

This study was performed to investigate the physical characteristics like compressive strength, permeability, porosity and the water quality removal characteristics of permeable concrete pavement filled with microbial-soil sheet to remove SS, organic matter and nutrients in artificial rainfall. As a result, it can show the removal efficiency is SS 90~95%, COD 85~93%, BOD 80~83%, T-N 61~75%, T-P 71~78% on WAPS I(W1) and WAPS II(W2). Therefore, permeable concrete pavement filled with microbial-soil sheet shows higher removal efficiency(SS 10%, organic matter and nutrients 30%) than a conventional porous concrete(W3). By filling microbial-soil sheet to permeable concrete pavement, we confirm that the function and efficiency are improved significantly and that a naturally-friendly facility can be developed and applied to treat non-point sources.

• Water for future
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• v.23 no.3
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• pp.351-361
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• 1990

Considering the hydrological los components such as evapotranspiration, interception, surface storage and infiltration, a rainfall excess model for forest watersheds is derived. The Morton model is adopted to estimate the evapotranspration under the wetted environmental conditions. Canopy effects and ground cover interception storage rates are used to determine the net rainfall rates arrived on the surface soil. The infiltration capacity on the permeable surface is estimated from the revised Green-Ampt model derived for the natural unsteady rainfall events. The rainfall excess model derived is applied with the data from Jangpyung watershed, one of the representative watersheds of IHP. Parameters which are calibrated with the data from ten storms, the hydrometeorological, land use and soil informations, and other researchers' papers are presented.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.704-710
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• 2012

The lower portion of sloping paddy fields normally contains excessive moisture and the higher water table caused by the inflow of ground water from the upper part of the field resulting in non-uniform water content distribution. Four drainage methods namely Open Ditch, Vinyl Barrier, Pipe Drainage and Tube Bundle for multiple land use were installed within 1-m position from the lower edge of the upper embankment of sloping alluvial paddy fields. This study was conducted to evaluate soil physical characteristics by drainage improvement in poorly drained sloping paddy field. The results showed that subsurface drainage by Pipe Drainage improves the productivity of poorly drained soils by lowering the water table and improving root zone soil layer condition. In an Pipe drainage plot, soil moisture drained faster as compared to the other drainage methods. Infiltration rate showed high tendency to Piper Drainage method about $20.87mm\;hr^{-1}$ than in Open Ditch method $0.15mm\;hr^{-1}$. And Similarly soil water and degree of hardness and shear strength phase of soil profile showed a tendency to decrease. From the above results, we found that when an subsurface drainage was established with at 1m position from the lower edge paddy levee of the upper field in sloping poorly drained paddy fields Pipe Drainage was the most effective drainage system for multiple land use.