• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.162-170
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• 2000

This study quantified the effects of urban greenspace on microclimate amelioration and atmospheric $CO_2$ reduction for several residential districts selected in Korea and Japan. The study also explored fire obstruction by urban trees to develop systematic planting guidelines. Transpiration by a Zelkova serrata tree (diameter at breast height: 15 cm) in a day of August equaled cooling effect of about 3 air conditioners running for 12 hours. Average air temperature for the growing season was 0.5$^{\circ}C$ and 1.2$^{\circ}C$ cooler, respectively, in districts with 12% and 22% cover of woody plants than in a district with no vegetation. Annual $CO_2$ uptake and $O_2$ production by woody plants were 3 times greater in a district which was 2 times higher in their cover. Woody plants played, in a district with their 22% cover, an important role through offsetting total $CO_2$ emission from the district by about 3% annually, and through producing 10% of annual $O_2$ requirement by all residents within the district. Appropriate planning strategies of residential greenspace, including species selection, planting layout, greenspace enlargement, and maintenance were suggested to improve microclimate amelioration, air purification, and fire obstruction.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.34-43
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• 2009

Based on previous research on ways of reducing an urban heat island phenomenon via an introduction of wind corridors, I conducted this study to see what influence a change in land cover arising of or going through urbanization has on wind corridors of urban space. As a target place, I chose Daegu city where is a representative extreme heat place in Korea and has been also largely expanded in size by incorporating its neighboring areas since the 1980s, expecially Dalseo District whose surface temperature gap is large. The population of Dalseo District has been sharply increased since its creation as a new administrative district in 1988. I studied on the urban microclimate change for a 20-year period by using satellite images on summer months in 1987, 1997 and 2007 in time frames. The finding of this study found that a reduction of natural land cover and an increase of artificial land cover serves as a disadvantageous factor for cold air creation and flowing and strikingly lowers the amount and height of cold air in the downtown area. It seemed that the cold air creation and flowing functions are influenced by land cover. In order to steadily create cold air and secure its flowing, it is thought that urban development or urban regeneration should be implemented by analysing the characteristics of the space surrounding the city. By doing so, a pleasant and healthy city could be formed.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.5
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• pp.55-64
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• 2015

In this study, negative air ions, which can increase comfort and positively influence human health, was set as an evaluative factor for school forests. The characteristics, location and microclimate of school forests were examined to determine an effective school forest model for maximum negative air ion generation. It also aimed to provide basic data for the development of urban green fields. The negative air ion concentrations were different according to the green types. The order from the highest to the lowest was: single-layer structure($934ea/cm^3$) > multi-layer structure($794ea/cm^3$) > grass($553ea/cm^3$) > bare ground($529ea/cm^3$). As for the correlation with microclimate, negative air ion concentration was negatively correlated with temperature. The negative air ion concentration was significantly different according to planting type. The negative air ion concentration was higher at single-layer structure sites than at multi-layer structure sites, which appears to indicate that the temperature is higher when the vegetation structure was single-layer compared to multi-layer. Wind speed was higher at the single-layer planted site than at the multi-layer planted site. The vegetation wind shielding effect was lower at single-layer planted sites than at multi-layer planted sites. The single-layer planted site provided more favorable conditions for the generation and dispersion of negative air ions.

• KIEAE Journal
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• v.11 no.5
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• pp.13-18
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• 2011

The overall aim of this study is to mitigate urban environmental problems. In particular, to reduce the effects of urban heat island phenomenon which is one of the urban planning perspective. This study focused on the analysis of the relationship between the urban heat island effect and the thermal and wind properties. To do this analysis, water space was virtually made at Yeol_Mae village Apt. Because it is very difficult to set up water space for the existing apartment complexes due to realistic constraints. This study, therefore has a strong sort of guidelines to create water space for newly formed city. It was based on the concept of virtual city through an in-depth analysis on reduction of urban heat island effects for the existing apartment along with creation of water space. To analysis site, Envi-Met Model developed by Michael Bruse was used. The results are as follows. The temperature went from 298.9K to 297.82K and The wind speed went from 1.42m/s to 1.43m/s. The results are slight in this study because creation of water space is planned to a small area of an apartment complex. But if the water space would be applied to a whole city, the mitigation effect of urban heat island would be bigger.

• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.272-280
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• 2016

Changes in land use and increase in urban energy consumption influence urban life. This study analyzed the characteristics and patterns of urban heat and presents management schemes to generate a comfortable and sustainable urban environment. The study aimed to demonstrate the positive effects of artificial ground greening on improving the microclimate through evapotranspiration using perennial herbs. We have designed a chamber that could control constant temperature and humidity, measure temperature reductions in each plant and changes in sensible heat and latent heat. This study identified Sedum kamtschaticum as the most effective plant in controlling temperature. At $22^{\circ}C$, $3.2^{\circ}C$ temperature reduction was observed, whereas four other plants showed a $1.5^{\circ}C$ reduction. At $25^{\circ}C$, $2.0^{\circ}C$ temperature reduction was observed. On the other hand, the use of Sedum sarmentosum resulted in the lowest effect. Zoysia japonica is the most commonly used ground covering plant, although the temperature reduction of Lysimachia nummularia was more effective at high temperature conditions. Sensible heat and latent heat were calculated to evaluate the thermal performance of energy. At a temperature >$30^{\circ}C$, L. nummularia and S. sarmentosum emitted high latent heat. In this study, we analyzed the thermal performance of green roof perennial plants; in particular, we analyzed the evapotranspiration and temperature reduction of each plant. Since the substrate depth and types, plant species, and seasonal change may influence temperature reduction and latent heat of green roofs, further studies are necessary.

• Journal of the Korean housing association
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• v.17 no.3
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• pp.51-60
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• 2006

Ten years have passed since the Demolishing Walls Campaign has started in Daegu. Recently, the campaign influenced to the other cities in Korea, such as Seoul, Incheon and Busan with various names regarding cities' circumstances. In these context, the study aims to highlight the identity of the Demolishing Walls Campaign compare Daegu with other cities where similar movement has started. In addition, the study evaluates the campaign in terms of physical, psychological and economical aspects to suggest some practical suggestion for the development of the campaign based on questionnaire survey. The research findings are as follows. The research shows that the identity of the Daegu Campaign is started by bottom-up approach based on citizens' participation compare with others cities' campaigns which are mainly started by the local government so called top-down method. The Daegu campaign influences the local people aware of their potential abilities in positively improving urban environment. The results of survey also highlights the advantages of green spaces which by the campaign in terms of environmental and economical aspects. Newly generating urban greens accept and store heat which Influences urban microclimate conditions and it possibly affects energy savings of the city. Most of survey participants eager to continue this campaign which shows positive results in various aspects by the local people. Therefore, the city government building a coalition of local people, NGOs, and interest group to keep the identity of the campaign in Daegu.

• Land and Housing Review
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• v.5 no.3
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• pp.131-136
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• 2014

The Hong Kong Housing Authority (HKHA) develops and implements a public housing programme to meet the housing needs of people who cannot afford private rental housing. The HKHA has an existing stock of about 740,000 public rental flats (PRH). According to the 2014 Policy Address, the Government aims to provide an average of about 20,000 PRH units and about 8,000 Home Ownership Scheme (HOS) units per year. We care for the environment. In developing new housing estates, we conduct thorough environmental studies such as microclimate studies and air ventilation assessment, and use passive design to harness the natural characteristics of our sites. We employ environment-friendly design and construction methods, using modular flat design, pre-cast and pre-fabricated construction techniques as well as recycled, green construction materials. We conduct Carbon Emission Estimation for all our projects, conserve the use of natural resources and reduce wastes throughout the life cycle of buildings. We care for people. We adopt the principles of Universal Design and Barrier Free Access for the convenience and welfare of people of all ages and abilities. We carry out Community Engagement to collect stakeholders' views and aspirations, and incorporate them in the design of our projects. We also carry out surveys of residents' views after the occupation of new estates to gauge our success and identify areas for improvement.

• Journal of Forest and Environmental Science
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• v.39 no.1
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• pp.40-48
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• 2023

Street trees have been incorporated into urban forests to regulate the microclimate and provide shade as well as provide aesthetic and environmental functions and to evaluate their physiological characteristics. Zelkova serrata is a major tree species that has been planted on various South Korean streets. We determined the physiological characteristics of Z. serrata in street trees of Goyang and Paju in Gyeonggi Province. According to survey sites, net CO₂ assimilation rates was 13.9-16.4 µmol CO₂ m^-2s^-1, chlorophyll fluorescence (Fv/Fm) was 0.80-0.82, and proline contents was showed 3.4-3.7 mg g^-1 FW. The studied trees were assumed to be physiologically stressed, but it was found that Z. serrata was planted as street trees were not significantly stressed when compared to chlorophyll fluorescence responses and proline contents. In the future, the continuous monitoring system is needed to evaluate the physiological characteristics of urban trees.

• Journal of Environmental Impact Assessment
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• v.30 no.2
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• pp.105-116
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• 2021

In the city of high population density crowded with buildings, Urban Heat Island (UHI) is intensified, and the city is vulnerable to thermal comfort. The maintenance of vacant land in downtown is treated as a factor that undermines the residential environment, spoils the urban landscape, and decreases the economic vitality of the whole region. Therefore, this study compared the effects on microclimate in the surrounding area according to the development scenarios targeting the vacant land in Songhyeon-dong, Jongno-gu, Seoul. The status quo, green oriented, building oriented and green-building mediation scenarios were established and ENVI-met was used to compare and analyze the impact of changes in wind speed, air temperature and mean radiant temperature (MRT) within 1 km of the target and the target site. The result of inside and 1 km radius the targeted area showed that the seasonal average temperature decreased and the wind speed increased when the green oriented scenario was compared with the current state one. It was expected that the temperature lowered to -0.73 ℃ or increased to 1.5 ℃ in summer, and the wind speed was affected up to 210 meters depending on the scenario. And it was revealed that green area inside the site generally affects inside area, but the layout and size of the buildings affect either internal and external area. This study is expected to help as a decision-making support tool for developing Songhyeon-dong area and to be used to reflect the part related to microclimate on the future environmental effects evaluation system.

• Journal of Environmental Science International
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• v.29 no.4
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• pp.325-337
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• 2020

The purpose of this study was to analyze the soil environment of urban neighborhood parks and to use them as basic data for evaluating the ecological functions of urban parks such as groundwater regeneration, flood control, microclimate regulation, adsorption and purification. The landscape design criteria were generally evaluated as advanced, and further monitoring and studies are needed to evaluate the various ecological functions. It is also necessary to improve the phosphoric acid and nitrogen contents, which tended to be low. In addition, continuous monitoring is needed to assess the proper soil environment according to the biological species, and to evaluate the ecological functions. The results of this study can be used to evaluate the groundwater recharge of urban parks. In particular, when the land of the neighboring park is used for various purposes, the level of access of the user may be increased. Therefore, factors that may adversely affect the user's health, such as heavy metals and organic matters, should be selected and selected as management criteria. In addition, follow-up studies considering fertilization standards suitable for trees and growth of introduced vegetation, etc. are needed urgently to improve the soil environment.