• Journal of Environmental Impact Assessment
• /
• v.19 no.5
• /
• pp.511-525
• /
• 2010

Understanding of the hydraulics of flow over vegetation is very important to support the management of fluvial processes. The objective of this study is to assess the effects of hydraulic influence by tree planting in a compound channel with vegetated floodplain. This study analyzes the influence of tree planting on hydraulic features in Young-river in Munkyung city using HEC-RAS and RMA-2 model. The study results showed that there is a rise in water surface elevation and decrease in velocity near vegetated area. It is also ascertained that only negligible effects was seen within the feasible range of freeboard for the existing levees. However, as hydraulic features can vary depending on the aspect of flood inundation during each flood period, it is necessary to accumulate data through continuous data collecting.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.35 no.2
• /
• pp.57-64
• /
• 1993

A modified kinematic wave model of the overland flow in vegetated filter strips was developed. The model can predict both flow depth and hydraulic radius of the flow. Existing models can predict only mean flow depth. By using the hydraulic radius, erosion, deposition and flow's transport capacity can be more rationally computed. Spacing hydraulic radius was used to compute flow's hydraulic radius. Numerical solution of the model was accomplished by using both a second-order nonlinear scheme and a linear solution scheme. The nonlinear portion of the model ensures convergence and the linear portion of the model provides rapid computations. This second-order nonlinear scheme minimizes numerical computation errors that may be caused by linearization of a nonlinear model. This model can also be applied to golf courses, parks, no-till fields to route runoff and production and attenuation of many nonpoint source pollutants.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.34 no.3 s.116
• /
• pp.12-22
• /
• 2006

The purpose of this study is to evaluate visual preferences of the methods for river embankment based on seasonal changes and to reveal the relationship between visual preference and effective factors, which are the physical and esthetic elements inside the river. For this research seven river embankment methods including concrete block, concrete wall, gabion, and vegetated concrete block were selected in Dongchon of Gwangyang. Twenty-eight pictures by the four pictures of each embankment method based on seasonal changes, the winter and summer of the first and second years after construction were used for a photo-questionnaire by 49 participants. In the analysis of the relationship between visual preference and effective factors, the independent variables included eight factors: form of the material, harmony with the surroundings, the cleanness of river floor, the green area of embankment methods, the water area in river floor, the stone and sand area in river floor, the planting area in river floor, and the area of embankment itself. The result of this study are as follows. First, visual preference in summer was higher than in winter, and the summer landscape of the second you scored the highest value for visual preference. Second, similarly to the way the vegetated concrete block produced a green effect, cobblestone and gabion embankments made of natural materials scored higher than others, whereas the concrete retaining wall scored the lowest of all methods because of it's artificiality. Third, the seven independent variables, except form of the material, are proved statistically significant at the 5% level. The water area in river floor, harmony with the surroundings, the planting area in river floor, and the cleanness of the river floor were revealed as more effective factors influencing visual preference. The research results suggest that the riverscape has to be controlled in terms of seasonal change and embankment methods. Natural materials and green effects in embankment methods are more important for increasing landscape preference, and the landscape factors inside a river should also be considered important variables. It is recommended that advanced study on other factors affecting visual preference of the riverscape be carried out to support this research.

• Journal of Environmental Science International
• /
• v.18 no.9
• /
• pp.1011-1015
• /
• 2009

The vegetated porous pavement can be installed as an alternative way to replace the traditional pavement, which contributes less to the water circulation system in the urban area. This study aims to an investigation based on the shadow and pressure of the vehicle system, where the turfgrass get grown and the green block get constructed on the grassy parking lot. This study might achieve these conclusions, in the case of use 'green block' makes grass parking lot, plant a kind of 'zenith' and takes sod thickness 40 mm are more efficient for turfgrass growth in the early times. In the case of parking over 8 hours in a day, after 5 weeks turfgrass growth would come into reduce. So over 4 hours parking and after 9 weeks, we need consider to setting up green block in grassy parking lot. The grassy ground would get pressured by the vehicles' load and it would bring into some damage due to the load after 3 weeks. So we should put the grass's growth root point under the designed a top of 'green block' level. When the vehicle amounts and parking density is in a low level, it could be an environmentally friendly product.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.16 no.2
• /
• pp.70-80
• /
• 2011

Estuarine ecosystem responds sensitively to natural and anthropogenic perturbations. lt is necessary to identify the direction of the change when the perturbation occurs as well as to understand the structure and functioning of estuarine ecosystem for a proper management of the area. In this study, the estuarine habitats were classified into different ecological districts so as to the switch from one district to another district could be related to the environmental change due to the perturbations. Total 16 ecological districts was defined according to the presence of barrage, salinity and vegetation characteristics. The defined ecological districts were applied to small estuaries in Goseong bay, south sea of Korea (Baedun, Guman, Maam, Goseong) to distinguish different regions which might have characteristic bottom topography, inclinations of river bottom, sediment characteristics, salinity structure and area of vegetation. Total 7 out of 16 ecological district was identified in this region; NFB (natural, fresh, bare), NHB (natural, high salinity, bare), NLV (natural, low salinity, vegetated) in natural (without barrage) estuaries and CFB (closed, fresh, bare), CFV( closed, fresh vegetated), CLV (closed, low salinity, vegetated), CHB (closed, high salinity, bare) in closed (with barrage) estuary. A comparison of environmental factors and biota between CHB and CLV demonstrated the effect of barrage on estuarine ecosystem. The height and sediment characteristics of CHB and CLV were similar but the average salinity was lower in CLV than in CHB due to the barrage, which produced favorable condition for the Phragmites australis in CLV. Information regarding the ecological districts in various sizes and location could be useful for predicting the ecosystem change due to natural and anthropogenic perturbations and for preparing management actions.

• Proceedings of KOSOMES biannual meeting
• /
• 2007.11a
• /
• pp.57-60
• /
• 2007

The Han River is divided into North and South Korea by NLL(Northern Limit Line) and its area has been blocked by CCL(Civil Control Line) since the Korean War in 1950. Satellite remote sensing, therefore, is uniquely suited to monitoring bar transformation in the region. In river with bar, the characteristics of its physical conditions have a close relationship with bar morphology. In this paper, a monitoring approach of bar transformation in the Han River Estuary is presented using RADARSAT/SAR images from 2000 to 2005 and spatial patterns of bar morphology are presented. It could be said that in the estuary vegetated area and natural levees are developed well, but bars are shifted after an event like a flood. It is also showed that suspended solids such as silt transported through the estuary could contribute highly to a sedimentation environment around Incheon.

• Journal of the Korean Professional Engineers Association
• /
• v.38 no.3
• /
• pp.1-5
• /
• 2005

As a method of anti-fire construction in forest region it is proposed to build fuelbreak(vegetated firebreak). Fuelbreak can separate the large area conifer forest into smell parts combined with natural firebreaks. Fuelbreaks can prevent forest fire effectively and also have other functions benefiting the forest ecosystem and environment. 3 kinds of construction skills are introduced for the silviculture technique to build fuelbreaks. And it is proposed to build the firebreaks network in national scale.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 1999.10a
• /
• pp.175-177
• /
• 1999

도시주변의 녹지의 대기정화기능이 중요하다는 인식이 일반화되어 있는 데 반하여, 여기에 대한 구체적인 분석이 이루어진 바는 없다. 특히, 전체면적의 87％가 녹지(임야, 전답 및 과수원)로 이루어진 개발제한구역(건설교통부, 1998)이 흡수하는 오염물질의 량은 궁금할 뿐 아니라 최근 논의되고 있는 개발제한구역해제와 관련하여 민감한 사항이기도 하다. 본 연구에서는 녹지의 대기정화기능에 대한 정량적인 분석을 목적으로 오염물질의 대기 중 확산이론에 근거하여 해석/수치모델을 모색했다.(중략)

• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.534-537
• /
• 2005

Polarization of the radar wave refers to the ellipticity angle and orientation angle of the polarization ellipse. An evaluation of the polarization response can help understand the scattering mechanisms involved for a particular area of interest or provide information for image classification and algorithm section. C- and L-band polarization responses measured at urban area show the results that the polarization behavior for dihedral comer reflector or short, thin cylinder reflector appears at located in city streets or buildings site which are lined up and the polarization behavior for a large conducting sphere appears at parts of test site particularly river, flat, and vegetated areas. Also, the co- and cross-polarized response graphs and polarimetric parameters are discussed.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2003.10a
• /
• pp.615-618
• /
• 2003

A prototype of 76 ha Shi-hwa constructed wetland was constructed for the first time in Korea to purify severely polluted stream water. Hydrology, vegetation(macrophyte) and water quality for Banwol and Donghwa wetland built in Shi-hwa tidal reclaimed area were monitored to evaluate the performance of the wetlands. The overall efficiency for the treatment of polluted stream water using the wetlands showed no significant improvement. The monthly average removal rates on SS, BOD, TN and TP for Banwol and Donghwa wetlands showed 66.5% and 62.8%, 14.8 and 34.3%, 33.9 and 47.1% and 20.8 and 51.6%, respectively. It is considered that three major factors, ie. wide fluctuations in inflow rate, short hydraulic retention time and small open area compared with vegetated area could have a great influence on low system efficiency.