• Journal of the Korean Institute of Landscape Architecture
• /
• v.43 no.4
• /
• pp.37-49
• /
• 2015

The goal of this research is to examine air temperature changes according to tree type, plantation type, roadside green area structure, and green volume of street green area within a city. The plantation type that could be analyzed for comparison by tree type with over 3 species was 1 rows of tree+shrubs. The results of analysis of average air temperature difference between pedestrian and car streets vis-a-vis 1 row of tree+shrub in high air temperature areas were: Pinus densiflora, $1.35^{\circ}C$; Zelkova serrata, $1.84^{\circ}C$; Ginkgo biloba, $2.00^{\circ}C$; Platanus occidentalis, $2.57^{\circ}C$. This standard large wide canopy species was analyzed by the roadside to provide shade to have a significant impact on air temperature reduction. In terms of analysis of the relationship between plantation type of roadside trees and air temperature, the average air temperature difference for 1 row of tree type was $1.80^{\circ}C$; for 2 rows of trees it was $2.15^{\circ}C$. In terms of analysis of the relationship between the roadside green area structure and air temperature, for tree type, average air temperature $1.94^{\circ}C$: for tree+shrub type, average air temperature $2.49^{\circ}C$; for tree+mid-size tree+shrub type, average air temperature $2.57^{\circ}C$. That is, air temperature reduction was more effective in a multi-layer structure than a single layer structure. In the relationship analysis of green volume and air temperature reduction, the air temperature reduction effect was enlarged as there was a large amount of green volume. There was a relationship with the green volume of the road, the size of the tree and number of tree layers and a multi-layer structured form of planting. The canopy volume was large and there were a great number of rows of the tree layer and the plantation type of multi-layer structure, which is what is meant through a relationship with the green volume along the roadside. Green composition standards for air temperature reduction effects and functional improvement were proposed based on the result. For a pedestrian street width of 3m or less in the field being ideal, deciduous broadleaf trees in which the canopy volume is small and the structure of the tree+shrub type through the greatest 1m green bend were proposed. For a pedestrian street width of over 3m, deciduous broadleaf trees in which the canopy volume is large and is multi-layer planted with green bend over 1m, tree+mid-size tree+shrub type was proposed.

• Journal of Soil and Groundwater Environment
• /
• v.9 no.4
• /
• pp.15-23
• /
• 2004

Deicer operations provide traffic safety during winter driving conditions in urban areas. Using large quantities of de-icing chemicals (i.e., $CaCl_2$ and NaCl) can cause serious environmental problems and may change behaviors of heavy metals in roadside sediments, resulting in an increase in mobilization of heavy metals due to complexation of heavy metals with chloride ions. To examine effect of de-icing salt concentration on the leaching behaviors and mobility of heavy metals (cadmium, zinc, copper, lead, arsenic, nickel, chromium, cobalt, manganese, and iron), leaching experiments were conducted on roadside sediments collected from Seoul city using de-icing salt solutions having various concentrations (0.01-5.0M). Results indicate that zinc, copper, and manganese in roadside sediments were easily mobilized, whereas chromium and cobalt remain strongly fixed. The zinc, copper and manganese concentrations measured in the leaching experiments were relatively high. De-icing salts can cause a decrease in partitioning between adsorbed (or precipitated) and dissolved metals, resulting in an increase in concentrations of dissolved metals in salt laden snowmelt. As a result, run-off water quality can be degraded. The de-icing salt applied on the road surface also lead to infiltration and contamination of heavy metal to groundwater.

• Journal of Environmental Impact Assessment
• /
• v.32 no.6
• /
• pp.437-449
• /
• 2023

This study measured PM₁₀ concentrations and wind speeds in buffer green spaces and neighborhood parks located along the road, and compared them with roadside measurementresults to understand the effect of mitigating PM₁₀ concentrations by type of green space and the influence of wind speeds on it. As a result of the analysis, the effect of mitigating PM₁₀ concentration was different depending on the type of roadside green space, and an increase in wind speed had a significant effect on reducing PM₁₀ concentration. In buffer green areas with high planting density, wind speed was low and PM₁₀ stagnated inside, resulting in the highest concentration. On the other hand, green areas in neighborhood parks with relatively low planting density had high wind speeds and the lowest PM₁₀ concentration. The non-green area within the neighborhood park recorded the highest wind speed, which was advantageous for the spread of PM₁₀, but the concentration was higherthan that of the green area. Therefore, in orderto reduce PM₁₀ concentration in roadside green space, it is necessary to create green space with good ventilation, and the combined effect of green space and wind speed seems to be more advantageous in reducing PM₁₀ concentration. Green spaces capture and remove PM inside, contributing to reducing the concentration of PM outside. In order to manage PM in the entire city and on roads, it is necessary to increase planting density and leaf area in roadside green spaces, such as buffer green spaces, so that PM can be removed within the green spaces. However, in green spaces such as neighborhood parks that are actively used by city residents, in orderto minimize damage to users due to PM, it is desirable to create green spaces with a structure that allows PM to spread to the outside rather than stagnate inside.

• Journal of Korean Society for Atmospheric Environment
• /
• v.32 no.1
• /
• pp.9-20
• /
• 2016

Ozone has been a problem in big cities. That is secondary air pollutant produced by nitrogen oxide and VOCs in the atmosphere. In order to solve this, the first to be the analysis of the $NO_x$ and VOCs. The main source of nitrogen oxide is the road mobile. Industrial sources in Seoul are particularly low, and mobile traffics on roads are large, so 45% of total $NO_x$ are estimated that road mobile emissions in Seoul. Thus, it is necessary to clarify the relation with the activity of road mobile source and $NO_x$ concentration. In this study, we analyzed the 4 locations with roadside automatic monitoring systems in their center. The V.K.T. calculating areas are set in circles with 50 meter spacing, 50 meter to 500 meter from their center. We assumed the total V.K.T. in the set radius affect the $NO_x$ concentration in the center. We used the hourly $NO_x$ concentrations data for the 4 observation points in July for the interference of the other sources are minimized. We used the intersection traffic survey data of all direction for construction of the V.K.T. data, the mobile activities on the roads. ArcGIS application was used for calculating the length of roads in the set radius. The V.K.T. data are multiplied by segment traffic volume and length of roads. As a result, the $NO_x$ concentration can be expressed as linear function formula for V.K.T. with high predictive power. Moreover we separated background concentration and concentrations due to road mobile source. These results can be used for forecasting the effect of traffic demand management plan.

• Korean Journal of Agricultural Science
• /
• v.32 no.1
• /
• pp.1-8
• /
• 2005

This study was carried out to examine the effect of heavy traffic on chemical properties of soil in roadside trees of Daejeon city. Soil samples at 0~10cm and 10~30cm depths were collected from soil of the roadside trees, Platanus occidentalis, and Ginko biloba, Soil pH in heavy traffic regions were around 7.0 at 0~10cm and 10~30cm soil depths because of spraying of calcium chloride for snow moving. The concentrations of Fe, Cd, Cu, Zn, and Pb in soil were higher in heavy traffic regions(Daejeon Station and Daehwa Industrial Complex) than in light traffic region (Chungnam National University). The result could be from rubbing and wear of car tire and metals when they travel.

• International Journal of Highway Engineering
• /
• v.15 no.2
• /
• pp.159-167
• /
• 2013

PURPOSES : In this study, the effects of when median exclusive bus lanes were applied to Daejeon trunk road (Wolpyeng crossway~Seodaejeon crossway, 6.3km) and (Daeduck Bridge 4~Kyeryong 4, 2.6km) by Microscopic Simulation VISSIM (5.0) was studied. The median exclusive bus lanes are one of the measures of transportation system manage techniques that can especially improve the efficiency of public transportation facilities. METHODS : According to the analysis of VISSIM on the Gyerong mainroad and Daedeok mainroad, when the median exclusive bus lanes were applied unlike when the roadside bus-only lanes were applied, the average travel speed of vehicles decreased but the average delay time and travel time increased. This arised from the changes in the geometric structure of the road which occurred the reduction of vehicle lane in the center of the road. RESULTS : In the case of bus, on the other hand, the average travel speed increased but the average delay time and travel time decreased. This is because the problems such as illegal parking and stopping, secondary road in out vehicle, and conflict of intersection right turn that roadside bus-only lanes occurred was solved. CONCLUSIONS : Although the introduction of median exclusive bus lanes will have a negative effect on general traffic flow due to the aggravation of travel, decrease of passenger car usage will lead to decrease of traffic volume. Therefore, smooth vehicle travel is expected.

• Journal of Korean Society of Forest Science
• /
• v.81 no.2
• /
• pp.117-123
• /
• 1992

In this study, the water soluble sulfur, lead and cadmium contents of Prunus yedoerais leaves were analysed. The water soluble sulfur content considered as a main pollution indicator was extracted by the conventional barium sulfate method and the concentrations were calculated. The results obtained are as follows ; 1. The water soluble sulfur contents of the leaves collected from the heavy traffic roadside trees were two time higher than that of control materials on average. It was presumed those trees has been under meaningful pollutants impact. The water soluble sulfur contents of leaves between Cheonju and Iri was higher than that between Iri and Kunsan. 2. The range of Pb contents from roadside trees was 11.9-34.5 ppm for exceeding the control. The trees grown on the right roadside were more heavliy Pb-contaminated. 3. The range of Cd contents from roadside trees grown between Iri and Kunsan, the site-to-site variations of Cd concentration was not significant.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2002.11a
• /
• pp.197-198
• /
• 2002

황사는 장거리를 이동해 한반도 둥에 영향을 미치는데, 호흡기 질환, 눈 질환, 알레르기 등 각종 질환을 유발하고, 최근에는 중국의 산업화에 따라 납, 카드뮴 같은 독성금속과 발암물질 둥 유해 오염물질까지 포함하고 있어 건강에 위협을 주고 있다. 나아가 황사에 포함된 미세 입자들이 대기 중에서 화학반응을 일으켜 각종 산화물을 생성하는 까닭에 만성기관지염을 악화시키고, 노인과 영아의 호흡기 질환을 유발하기도 한다 그밖에 황사는 햇빛을 차단해 시정거리를 감소시키고 항공기 운항에도 영향을 미친다. (중략)

• Korean Journal of Environmental Agriculture
• /
• v.10 no.1
• /
• pp.1-10
• /
• 1991

The object of this stduy was to investigate the pollution of Pb in paddy field soil with different distance from roadside and to find out the relationship between the ratio of chemical fractions of total Pb and soil characteristics. Lead from automobiles is exhausted as particulates composed primarily of halide compounds (PbBrCl, $PbBr_2$, $PbCl_2$). The samples of soil were collected directly from the paddy fields with different distance from the roadside of highway and expressway which are located in Kyungpook province. A sequential extraction procedure was used to fractionate Pb in paddy field soil into the disignated forms of water soluable, exchangeable, organically bounded, carbonate, sulfide, and residual Pb. Results obtained are summerized as follows. 1. The content of Pb in paddy field soil was the highest in Chungdo, 30.0 ppm, the lowest in Koryung, 14.8 ppm, and the total average content was 21.9 ppm. The effect of traffic volume was not clear, but a slight difference according to the order of opened year of roads was showed. 2. The effect of distance from roadside was not clear. The content of Pb in paddy field soil with different distance from roadside was 22.2 ppm within l0m, 22.1 ppm in 10∼30m, 22.2 ppm in 30∼50m. and 21.3 ppm beyond 50m. 3. The distribution of Pb fractions in soil showed a wide difference depending on soil properties. The average content of exchangeable. organically bounded, carbonate, sulfide, and residual Pb was 8.6%, 33.6%, 29.8%, 21.5%, and 6.7%, of total Pb in the soil, respectively. 4. The content of organically bounded Pb in soil showed highly positive correlation with organic matter and CEC, while the content of exchangeable Pb was highly negative correlation. 5. With higher soil organic matter and CEC, organically bounded Pb fraction tend to be higher but exchangeable Pb fraction tend to be lower. Other forms of Pb showed no difference with soil organic matter contend and CEC. The distribution of Pb fraction related to CEC showed similiar tendency with that of organic matter content.

• Journal of Environmental Science International
• /
• v.16 no.2
• /
• pp.159-169
• /
• 2007

The overall purpose of this study was to investigate pedestrians and commercial business men and employers' recognition on management of street trees and green spaces along street sides. The followings were main results of this study. Both pedestrians and commercial business men and employers mostly perceived positive influence of street trees on urban environment and their business. In addition, pedestrians gave higher scores of positive influence of trees function than those of commercial business men and employers. Pedestrians showed strong intention to participate management activities of street trees or green spaces. This study indicated that negative perception on street trees came from improper management rather than existence of street trees. Therefore, more intensive management actions are needed.