• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.81-88
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• 2011

본 연구는 관리조방형 옥상녹화 시스템의 우수유출 저감 및 유출지연 효과를 규명하기 위하여 2007년~2010년의 4년간 연구를 진행하였다. 실험대상지는 서울여자대학교 행정관 옥상에 조성된 관리조방형 옥상녹화지로 2007년에 조성하였으며, 세덤류 및 다년생 초화류를 포함하여 총 18종의 식물을 식재하였다. 우수유출 저감 및 지연효과를 지속적으로 모니터링하기 위해 옥상녹화지를 통과한 우수를 저장할 수 있는 시스템을 설치하여 유출수의 유입량 및 시간을 측정였다. 조사기간 중 총 24번의 강우사례를 분석한 결과 단위면적당 평균 약 90.3%(78.8~99.3%)의 유출량이 저감되었으며, 지연시간은 평균 약 1.6시간으로 나타났다. 본 연구결과를 종합분석해본 바, 빗물이 거의 전량 유출되는 도심의 건축물 옥상을 녹화함으로써 옥상에 유입되는 우수의 유출을 지연 및 저감시켜 도심의 수순환체계 개선에 기여할 수 있을 것으로 생각된다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.49-55
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• 2020

In this study, the surface temperature of the roof green system using ALSRBA(Artificial Lightweight Soil Recycled with Bottom Ash) was measured in each season and the thermal property of the ALSRBA was investigated. As a result, it was certified that ALSBRA has superior thermal property than the usual artificial soil. In addition, The daily temperature range in each season was measured to investigate the thermal isolation property of EUS(Existing Unit System) and DUS(Developed Unit System). The result showed that the thermal isolation effect of EUS was lower than that of SPSS(Site-Place-Soil System), but thermal isolation effect of DUS was similar to that of SPSS because DUS has continuous ALSBRA layer by removing unit barrier.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.449-449
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• 2015

최근 비정상성을 띄는 강우 사상으로 인해 도심지에서는 유출량이 증가하여 많은 피해를 보이고 있다. 이를 해결하기 위해 투수성 포장재, 옥상 녹화, 침투 트렌치, 빗물 정원 등의 연구가 활발히 진행되고 있다. 하지만 이를 유역에 속해 있는 전체 도심지에 적용하기에는 많은 자원이 소비된다. 이에 본 연구는 서울시의 청계천 유역을 대상으로 강우유출 모형인 SWMM을 이용하여 소유역 별로 투수성 포장재와 옥상 녹화 사업을 적용하여 유출저감 효과를 분석하였다. 적용된 강우는 강우강도에 따라 각 시설들이 갖는 한계점을 분석하기 위해 서울(108) 지점을 기준으로 재현기간 80년, 지속기간 24시간에 대해 초과확률 50%에 해당하는 Huff 3분위를 채택하였고, 투수성 포장재와 옥상녹화는 서로 적용 위치가 달라 두 가지 사업의 조합을 통해 각각의 효과를 분석하였다. 또한 사업 우선순위를 위해 소유역별 사회, 환경적인 자료를 취합하여 우선순위화 하였다. 이를 통해 한정된 자원 내에서 최적의 개발 지역을 선정하여 최대한의 효과를 도모하고자 한다.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.6
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• pp.190-197
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• 2012

The purpose of this study was to evaluate thermal environment and heat budget of light thin layer green roof through an experiment in order to quantify its heat budget. Two concrete model boxes($1.2m(W){\times}1.2m(D){\times}1.0m(H)$) were constructed: One experiment box with Zoysia japonica planted on substrate depth of 10cm and one control box without any plant. Between June 6th and 7th, 2012, outside climatic conditions(air temperature, relative humidity, wind direction, wind speed), evapotranspiration, surface and ceiling temperature, heat flux, and heat budget of the boxes were measured. Daily maximum temperature of those two days was $29.4^{\circ}C$ and $30^{\circ}C$, and daily evapotranspiration was $2,686.1g/m^2$ and $3,312.8g/m^2$, respectively. It was found that evapotranspiration increased as the quantity of solar radiation increased. A surface and ceiling temperature of those two boxes was compared when outside air temperature was the greatest. and control box showed a greater temperature in both cases. Thus it was found that green roof was effective in reducing temperature. As results of heat budget analysis, heat budget of a green roof showed a greater proportion of net radiation and latent heat while heat budget of the control box showed a greater proportion of sensible heat and conduction heat. The significance of this study was to analyze heat budget of green roof temperature reduction. As substrate depth and types, species and seasonal changes may have influences on temperature reduction of green roof, further study is necessary.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2008.04a
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• pp.125-127
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• 2008

• Horticultural Science & Technology
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• v.31 no.4
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• pp.503-511
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• 2013

The purpose of this study was to evaluate temperature reduction and heat budget of extensive modular green roof planted with Sedum sarmentosum and Zoysia japonica. Plant height and green coverage were measured as plant growth. Temperature, net radiation and evapotranspiration of concrete surface, green roof surface, in-soil and bottom were measured from August 2 to August 3, 2012 (48 hours). On 3 P.M., August 3, 2012, when air temperature was the highest ($34.6^{\circ}C$), concrete surface temperature was highest ($57.5^{\circ}C$), followed by surface temperature of Sedum sarmentosum ($40.1^{\circ}C$) and Zoysia japonica ($38.3^{\circ}C$), which proved temperature reduction effect of green roof. Temperature reduction effect of green roof was also shown inside green roof soil, and bottom of green roof. It was found that Zoysia japonica was more effective in temperature reduction than Sedum sarmentosum. Compared with the case of concrete surface, the highest temperature of green roof surface was observed approximately 2 hours delayed. Plant species, temperature and soil moisture were found to have impact on surface temperature reduction. Plant species, air temperature, soil moisture and green roof surface temperature were found to have impact on temperature reduction in green roof bottom. As results of heat budget analysis, sensible heat was highest on concrete surface and was found to be reduced by green roof. Latent heat flux of Zoysia japonica was higher than that of Sedum sarmentosum, which implied that Zoysia japonica was more effective to improve thermal environment for green roof than Sedum sarmentosum.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.947-951
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• 2015

This study presents proper irrigation interval for the soil condition of green roof system and the smooth growth of the landscaping herbaceous plants available and reveal the need for irrigation in rooftop conditions. Twenty kinds of greenery plants are tested on ground paved wood panels where rain and wind shielder is installed. Before test, irrigation is conducted fully to experimental plants and then soil moisture in pot is measured after every ten minutes. In conclusion, it is suggested that the irrigation has to be carried out every 4~5 days in order to minimize water and heat stress of plants. Also, irrigation management is an essential prerequisite for good condition and the smooth growth of plants and environmental effects in green roof system.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.1
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• pp.96-105
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• 2018

This study examined the growth of herb plants in response to irrigation on a green rooftop area in order to select herb plants that can be used for rooftop greening. Apple Mint (Mentha suaveolens), Lemon balm (Melissa officinalis), Spearmint (Mentha spicata), Pineapple sage (Salvia elegans), Choco Mint (Mentha ${\times}$ piperita 'Choco Mint'), Ox-eye Daisy (Chrysanthemum leucanthemum), Roman Chamomile (Anthemis nobilis) and Thyme (Thymus vulgaris) showed increased growth when irrigated. Conversely, Lavender (Lavendula angustifolia ), Peppermint (Mentha ${\times}$ piperita ), Vicks Plant (Plectranthus tomentosa), Feverfew (Tanacetum parthenium), Rosemary (Rosmarinus officinalis), Tansy (Tanacetum vulgare), Lemon Verbena (Aloysia triphylla), Heliotrope (Heliotropium arborescens), Soapwort (Saponaria officinalis) and Lady's mantle (Alchemilla vulgaris) demonstrated satisfactory growth regardless of irrigation. Peppermint, Tansy, Lemon Verbena, Soapwort, and Lady's mantle seem to be suitable for green rooftop because of their overwintering ability and drought hardiness. Pineapple sage, Apple Mint and Thyme would seem to be inappropriate for rooftop greening because they showed negative growth response to drought and failed overwintering. Although Spearmint, Lemon balm, Choco Mint, Ox-eye Daisy and Roman Chamomile had reduced growth during dry conditions, they were able to overwinter satisfactorily and can be used as rooftop plants with irrigation.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.6
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• pp.107-116
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• 2013

This study was undertaken to investigate the characteristics of retention and evapotranspiration in the extensive greening module of sloped and flat rooftops for stormwater management and urban heat island mitigation. A series of 100mm depth's weighing lysimeters planted with Sedum kamtschaticum. were constructed on a 50% slope facing four orientations(north, east, south and west) and a flat rooftop. Thereafter the retention and evapotranspiration from the greening module and the surface temperature of nongreening and greening rooftop were recorded beginning in September 2012 for a period of 1 year. The characteristics of retention and evapotranspiration in the greening module were as follows. The water storage of the sloped and flat greening modules increased to 8.7~28.4mm and 10.6~31.8mm after rainfall except in the winter season, in which it decreased to 3.3mm and 3.9mm in the longer dry period. The maximum stormwater retention of the sloped and flat greening modules was 22.2mm and 23.1mm except in the winter season. Fitted stormwater retention function was [Stormwater Retention Ratio(%)=-18.42 ln(Precipitation)+107.9, $R^2$=0.80] for sloped greening modules, and that was [Stormwater Retention Ratio(%)=-22.64 ln(X)+130.8, $R^2$=0.81] for flat greening modules. The daily evapotranspiration(mm/day) from the greening modules after rainfall decreased rapidly with a power function type in summer, and with a log function type in spring and autumn. The daily evapotranspiration(mm/day) from the greening modules after rainfall was greater in summer > spring > autumn > winter by season. This may be due to the differences in water storage, solar radiation and air temperature. The daily evapotranspiration from the greening modules decreased rapidly from 2~7mm/day to less than 1mm/day for 3~5 days after rainfall, and that decreased slowly after 3~5 days. This indicates that Sedum kamtschaticum used water rapidly when it was available and conserved water when it was not. The albedo of the concrete rooftop and greening rooftop was 0.151 and 0.137 in summer, and 0.165 and 0.165 in winter respectively. The albedo of the concrete rooftop and greening rooftop was similar. The effect of the daily mean and highest surface temperature decrease by greening during the summer season showed $1.6{\sim}13.8^{\circ}C$(mean $9.7^{\circ}C$) and $6.2{\sim}17.6^{\circ}C$(mean $11.2^{\circ}C$). The difference of the daily mean and highest surface temperature between the greening rooftop and concrete rooftop during the winter season were small, measuring $-2.4{\sim}1.3^{\circ}C$(mean $-0.4^{\circ}C$) and $-4.2{\sim}2.6^{\circ}C$(mean $0.0^{\circ}C$). The difference in the highest daily surface temperature between the greening rooftop and concrete rooftop during the summer season increased with an evapotranspiration rate increase by a linear function type. The fitted function of the highest daily surface temperature decrease was [Temperature Decrease($^{\circ}C$)=$1.4361{\times}$(Evapotranspiration rate(mm/day))+8.83, $R^2$=0.59]. The decrease of the surface temperature by greening in the longer dry period was due to sun protection by the sedum canopy. The results of this study indicate that the extensive rooftop greening will assist in managing stormwater runoff and urban heat island through retention and evapotranspiration. Sedum kamtschaticum would be the ideal plant for a non-irrigated extensive green roof. The shading effects of Sedum kamtschaticum would be important as well as the evapotranspiration effects of that for the long-term mitigation effects of an urban heat island.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2010.04a
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• pp.250-254
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• 2010