• Title/Summary/Keyword: 지표면 피복재료

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Simulation of Alpine Field Soil Loss by Outdoor Rainfall Simulator (실외인공강우에 의한 경사밭의 토양 유실량 모의)

  • Shin, Hyun-Jun;Won, Chul-Hee;Kim, Tae-Yoo;Choi, Eu-Tteum;Choi, Joong-Dae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.1242-1246
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    • 2010
  • 호우기간 동안 내리는 빗방울의 타격에 의해 흙 입자는 침출수와 함께 이동하여 지표 아래 공극을 막는다. 다져진 지표면은 유출과 토양 유실의 원인이 된다. 발생원으로부터 유실되는 토양을 Polyacrylamide(PAM)과 지표피복재를 이용하여 저감하는 연구를 하였다. PAM은 토양 입자의 결합력을 강화시키고 이탈을 방지하여 토양 유실을 감소시키는데 효과적이다. 이 연구의 목적은 PAM을 덧붙인 볏짚거적, 볏짚거적+톱밥, 볏짚거적+왕겨 등을 이용하여 인공강우 동안 토양 유실을 저감하는 효과를 조사하는 것이다. 실험은 1시간 동안 강우를 모의했으며, 실험 도중에 6~7회 수질 샘플을 채취하였다. 초기유출시간은 총 4차 실험중에 2차를 제외한 나머지에서 볏짚거적+왕겨+PAM이 가장 느리게 유출되었다. SS와 탁도 항목에서 1차 실험을 제외한 나머지 실험에서 볏짚거적+톱밥+PAM이 효과적이었다. 단순히 PAM을 사용하는 것보다 잔여물(residue)을 같이 혼합한 피복재료가 토양 유실과 유출을 저감하는데 더욱 효과적인 것으로 나타났다. 본 연구 결과는 향후 농촌지역에 토양 유실저감에 필요한 자료로 활용할 수 있을 것이라 판단된다.

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Growth and Ground Coverage of Ophiopogon japonicus 'Nanus' under Different Shade Conditions (차광처리에 따른 애기소엽맥문동의 생장과 피복에 관한 연구)

  • Kang, Ae-Ran;Park, Seok-Gon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.2
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    • pp.68-75
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    • 2017
  • Demand for dwarf mondo grass (DMG; Ophiopogon japonicus 'Nanus') as an ornamental garden plant is expected to grow in the future. The purpose of this study was to investigate the levels of shade tolerance and ground cover by growing DMG under a variety of shade conditions for 18 months (May 2015~October 2016). DMG plants grown in bare ground for 3 years in Jangheung-gun, Jeonnam were used for testing. In an experimental site created in Naju city in Jeonnam, the DMG was planted in planters ($70cm{\times}70cm{\times}24cm$) and covered with a shading curtain to block natural light. Shaded conditions were then arranged under different levels of shade (0%, 55% and 75%). When the plants were grown, growth (leaf size, the number of leaves, fresh weight and dry weight) and ground coverage of DMG were analyzed. According to the results, DMG growth in terms of leaf size and the number of leaves was statistically higher under zero shade (full sunlight), when compared to other shaded conditions. DMG's fresh and dry weights were significantly greater under 0% and 55% shade, compared to those under 75% shade. The degrees of shade tolerance required for normal growth of DMG were found in the range of 0~50%, meaning that more than 50% shade may decrease plant growth. There were no statistical differences in ground coverage rates of DMG under different levels of shade. When 220 tillers were planted per $1m^2$ of plot, up to 80% of the area was covered by DMG after 18 months. Since DMG requires nutrient-rich soil to grow, sufficient nitrogen fertilizers are proposed to accelerate the ground cover of DMG. As DMG remained alive over the winter in the experiments, this study also suggests that DMG can be planted in the southern temperate region.

Assessment on Thermal Environment and Human Thermal Comfort in Residential Building Block through Field Measurement (실측을 통한 공동주택 단지 내에서의 온열환경 및 거주자 쾌적감 평가에 관한 연구)

  • Lim, Jong-Yeon;Hwang, Hyo-Keun;Song, Doo-Sam;Kim, Tae-Yeon
    • 한국태양에너지학회:학술대회논문집
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    • 2008.04a
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    • pp.311-317
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    • 2008
  • As outdoor environment become worse due to concentration of population in large cities, the importance of environmental control strategies such as the arrangement of green space or water space and ventilation paths, has been increasingly recognized. However, most of the studies focus on the assessment on outdoor thermal environment, few studies focus on the interrelationship between thermal environment in residential block and human thermal comfort. The aims of this study is to develop the outdoor planning method to reduce the heating/cooling load in an apartment unit or entire block by the sustainable approaches in outdoor environmental design. In this paper, on the basis of the prior studies, the effect of the outdoor thermal environment on human thermal comfort will be analysed.

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The Influence of Materials for Surface Mulching on Soil Temperature and Vegetative Growth of Apple Nursery Trees (지표면 멀칭재료가 지온과 사과나무 묘목의 수체생육에 미치는 영향)

  • SaGong, Dong-Hoon;Lee, Su-Jin;Han, Su-Gon;Yoon, Tae-Myung
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.13 no.1
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    • pp.1-9
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    • 2011
  • This study was conducted to investigate the influence of different polyethylene film (P.E. film) for mulching on the changes in soil temperature and the production of good feathered apple nursery trees. M.9 rootstocks with stem diameter of 9.1~11.0 mm were planted in plots covered with different P.E. film (i.e., transparent P.E. film, black P.E. film, and bare soil as control). Three weeks after planting, the rootstocks were veneer grafted with 'Sinano Sweet' apple cultivar. In the middle of June, BA was sprayed to nursery for inducing feathering during the growing season. The soil temperature of the control was higher than air temperature by about $0.7^{\circ}C$ from mid April to early October, and that of P.E. film mulching was about $1{\sim}5^{\circ}C$ higher than that of the control. The soil temperature under transparent P.E. film was about $2{\sim}3^{\circ}C$ higher than that under black P.E. film. The diurnal range of soil temperature under the black P. E. film was lowest among all treatments. The P.E. film mulching induced better tree growth and feathering than bare soil. Percentage of good feathering apple nursery of black P.E. film was highest among all treatments because the soil temperature unuder black P.E. film in the early growing season was higher than that of the control and the number of days when the maximum soil temperature was over $35^{\circ}C$ in the summer was lower than that under the transparent P.E. film.

Calculation of Surface Broadband Emissivity by Multiple Linear Regression Model (다중선형회귀모형에 의한 지표면 광대역 방출율 산출)

  • Jo, Eun-Su;Lee, Kyu-Tae;Jung, Hyun-Seok;Kim, Bu-Yo;Zo, Il-Sung
    • Journal of the Korean earth science society
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    • v.38 no.4
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    • pp.269-282
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    • 2017
  • In this study, the surface broadband emissivity ($3.0-14.0{\mu}m$) was calculated using the multiple linear regression model with narrow bands (channels 29, 30, and 31) emissivity data of the Moderate Resolution Imaging Spectroradiometer (MODIS) on Earth Observing System Terra satellite. The 307 types of spectral emissivity data (123 soil types, 32 vegetation types, 19 types of water bodies, 43 manmade materials, and 90 rock) with MODIS University of California Santa Barbara emissivity library and Advanced Spaceborne Thermal Emission & Reflection Radiometer spectral library were used as the spectral emissivity data for the derivation and verification of the multiple linear regression model. The derived determination coefficient ($R^2$) of multiple linear regression model had a high value of 0.95 (p<0.001) and the root mean square error between these model calculated and theoretical broadband emissivities was 0.0070. The surface broadband emissivity from our multiple linear regression model was comparable with that by Wang et al. (2005). The root mean square error between surface broadband emissivities calculated by models in this study and by Wang et al. (2005) during January was 0.0054 in Asia, Africa, and Oceania regions. The minimum and maximum differences of surface broadband emissivities between two model results were 0.0027 and 0.0067 respectively. The similar statistical results were also derived for August. The surface broadband emissivities by our multiple linear regression model could thus be acceptable. However, the various regression models according to different land covers need be applied for the more accurate calculation of the surface broadband emissivities.

Experimental Study on behavior of the Lightweight Air-foamed Soil Considering Freezing-thawing and Soaking Conditions (동결융해 및 수침조건을 고려한 경량기포혼합토의 거동 실험 연구)

  • Kang, Daekyu;Shin, Eunchul
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.5
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    • pp.37-46
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    • 2016
  • In order to determine the variability of environmental characteristics of lightweight air-foamed soil using marine clay according to freezing-thawing and soaking conditions, unconfined compressive strength of the lightweight air-foamed soil samples made by changing the amount of cement under curing conditions of outdoor low temperature, underground or indoor wetting were observed. Compressive strength was not increased under freezing-thawing (temperature range of $-9.1^{\circ}C{\sim}17.2^{\circ}C$) regardless of the amount of cement but the more cement using, it was increased rapidly by underground curing conditions within 30 cm beneath ground level. Therefore, it is necessary to install insulation layer cutting off exterior cold air after construction of lightweight air-foamed soil in condition of freezing-thawing. Bulk density was increased too small under the long-time soaking condition, it tended to decrease rapidly when samples were dried up and had below 6% of water contents. But variability of compressive strength and bulk density was very small for preventing drying and keeping its wet state. The lightweight air-foamed soil that installed beneath ground water level or covered by soil can be evaluated as a long-term reliable construction material.