• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.6
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• pp.1-13
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• 2018

Mapping radiation heat flux of urban area is essential for urban design and landscape planning. Because controlling urban geometry and generating green space are important urban design strategies for reducing urban heat, urban planner and designer need to recognize the micro urban heat distribution for adequate urban planning. This study suggests a new methodology for mapping urban radiation heat flux in a micro scale considering buildings and trees' shade. For doing that, firstly, we calculate net radiation for each urban surfaces (building, road (not shaded, building shaded, tree shaded), ground (not shaded, building shaded, tree shaded), tree (not shaded, building shaded)). Then, by multiplying the area ratio of surfaces to the net radiation, we can obtain the radiation heat flux in micro-scale. The estimated net radiation results were found to be robust with a $R^2$ of 90%, which indicates a strong explanatory power of the model. The radiation heat flux map for 12h $17^{th}$ August explains that areas under the building and tree have lower net radiation heat flux, indicating that shading is a good strategy for reducing incident radiation. This method can be used for developing thermal friendly urban plan.

• Journal of Environmental Science International
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• v.32 no.11
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• pp.811-820
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• 2023

This study investigated the protective effects of shade nets on Abies koreana seedlings subjected to high temperature and luminosity stress, which are pertinent for plant survival in climate change scenarios. This study, conducted at Konkuk University, compared the growth, survival, and soil conditions of 3-year-old specimens across natural, greenhouse, and shaded settingsfrom July to September 2022. Our findings demonstrated that shade nets significantly enhanced seedling survival by moderating soil temperature and moisture. This is particularly evident in high-temperature conditions, where shade nets mitigate stress on seedlings and safeguard them from excessive sunlight exposure. Proper net installation height and location are crucial for optimal temperature and humidity control, suggesting broader applicability for various species and offering strategies to combat the ecological impacts of climate change.

• Journal of the Korean Institute of Landscape Architecture
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• v.21 no.1
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• pp.1-12
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• 1993

This studies were conducted to investigate on the shade adaptation of native Sedum kamchaticum and Disporum smilacinum. All plants were grow under the controlled light intensity conditions, which controlled by two shading materials, white and/or black shading net. The results obtained were as follow. 1. Daily changes of the shading area around of the building were various by building height, width and direction. 2. Upper canopy was composed to Pinus densiflora as dominant species in native sites of Disporum species. 3. Many branches of Disporum smilacinum were sprouted after pinching. However their growth were less elongated shorter than those of Disporum viridescens. 4. Sedum sarmentosum was poor growth under the low relative light intensity as 50%, however, the growth of this species closely was similiar as under the full sun condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.504-509
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• 2015

This research carried out to figure out the effect of the green manure crop cultivated at a preparation field and the shading net on the growth, development, and quality of ginseng. Followings are results obtained from the research. Leaf width of ginseng under the shading net of a two-layered blue and two-layered black polythylene net (TBTBPN) was good at rye and hairy vetch cultured group. Leaf length of ginseng under the shading net of a three-layered blue and one-layered black polyethylene net (TBOBPN) was good at barley and hairy vetch cultured group. Meanwhile, leaf width was good at hairy vetch cultured group. Leaf length of ginseng under a blue polyethylene sheet (BPS) was good at a barley and barley + hairy vetch cultured group, but stem length was shorter compare to other shading net cultivations. Root weight of ginseng was good under the shading net of a two-layered blue and two-layered black polyethylene net (TBTBPN) at a rye and hairy vetch cultured group, and was good under the shading net of a three-layered blue and onelayered black polyethylene net (TBOBPN) at a barley + hairy vetch cultured group, but there was no significant difference under blackout screen according to manure crop varieties. Ratio of rusty root was 10.2% at the barley cultured group under the shading net of a two-layered blue and two-layered black polyethylene net (TBTBPN), and was 23.1% at hairy vetch cultured group under shading net of a three-layered blue and one-layered black polyethylene net (TBOBPN). Ratio of rusty root was the lowest at a rye cultured group regardless the shading nets. Content of the ginsenoside was the highest at the rye cultured group under the shading net of two-layered blue and two-layered black polyethylene net (TBTBPN), was the highest at the barley cultured group under the shading net of a three-layered blue and one-layered black polyethylene net (TBOBPN), and was the highest at the rye cultured group under the blackout screen.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.38-53
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• 1998

This study quantified annual net carbon uptake by urban landscape trees and provided equations to estimate it for Ginkgo biloba, platanus occidentalis, Zelkova serrata and Acer palmatum, based on measurement of exchange rate for two years growing seasons from Sep., 1995 to Aug., 1997. The carbon uptake was significantly influenced by photosynthetic capacity, photon flux density and pruning. Ginkgo biloba showed the highest rate of net CO\sub 2\ uptake per unit leaf area and Acer palmatum did the lowest rate among those species. A tree shaded by adjacent building over the growing seasons showed net CO\sub2\ uptake per unit leaf area much lower than another tree of the same species less shaded. Annual net carbon uptake per tree was 19kg for Zelkova serrata, but only 1 kg for Ginkgo biloba and Platanus occidentalis with crown volume dwarfed from pruning. One Zekoval serrata tree annually offset carbon emission from consumption of about 32 liter of gasoline or 83 kWh of electricity. Strategies to improve CO\sub 2\ uptake by urban landscape trees include planting of species with high potosynthetic capacity, sunlight-guaranteed road and building layout for street trees, planting of shade-tolerant species in the north of buildings, and relocation of utility lines to underground and minimized pruning.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.476-487
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• 2001

In this study, three tree species (Populus euramericana, Kalopanax pictus and Quercus serrata) exhibiting different levels of shade tolerance were employed to investigate photosynthetic responses to the lower light condition on forest floors. Chlorophyll contents, spectral properties and photosynthetic characteristics were examined by using the tree species grown under high light intensity (PPFD $920{\mu}mol\;m^{-2}s^{-1}$) or low light intensity (PPFD $80{\mu}mol\;m^{-2}s^{-1}$). Plants grown under the low light intensity tended to have reduced leaf area, chlorophyll content per unit leaf area, light absorption and respiration in the shade intolerant tree species of P. euramericana. However, the shade tolerant species K. pictus and Q. serrata showed increased leaf area, chlorophyll content and net apparent quantum yield. Therefore, light absorption and light utilization efficiency were improved under the low light intensity. Also shade tolerant species maintained activities of photosystems and $CO_2$ fixation systems with little changes in low light intensity condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.390-396
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• 2009

To select optimal shade material in paddy soil, growth characteristics and ginsenoside contents were investigated in new cultivar, 'Cheonpoong' of three-year-old ginseng cultured under three kinds of shade materials such as three-layered blue and one-layered black PE (polyethylene) net (TBPN), blue PE sheet (BPSS), and aluminium-coated PE sheet (APSS). The order of light transmission ratio and air temperature by shade materials were BPSS > APSS > TBSB among three shade materials. Average soil water tension in PDC and IDC was 64 mbar (absolute soil moisture, 25%) and 123 mbar (absolute soil moisture, 17%), respectively, and soil water tension in IDC was changed more distinctly than that of PDC by season and shade materials. Yield in PDC was distinctly decreased more than that in IDC because of the increase of discolored-leaf and rusted-root ratio. BPSS and TBPN among three shade materials were the most effective on the increase of yield in PDC and IDC, respectively. Ratio of rusty-colored root showed not significant difference by drainage class and shade materials. Contents of panaxatriol ginsenoside (Rg1, Re and Rf) were decreased in PDC, while it of panaxadiol ginsenoside (Rb1, Rc and Rd) were increased in IDC. Total ginsenoside contents of IDC was distinctly higher than that of PDC, and BPSS showed the highest contents among three shade materials regardless of poorly and imperfectly drainage class.

• Journal of Korea Foresty Energy
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• v.21 no.1
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• pp.65-75
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• 2002

The study was carried out to determine the growth and biomass production of major deciduous trees including Betula platyphylla var. japonica, Betula schmidtii, Zelkova serrata, Acer mono, Prunes sargentii, and Ligustrum obtusifolium subjected to artificial shade treatment in nursery field. The six deciduous trees seedlings grow for 2 years under different light intensity of 100%, 38-62%, 22-28%, 7-20%, and 2-6% of the full sun light intensity. The results were as follows; In the seedling heights and root collar diameters of shade intolerant species like Betula platyphylla var. japonica and Betula schmidtii, the relative growth rates of seedlings grown in full sun showed 2 times as compared with those subjected to the shade treatment of 2-6% light intensities of full sun. In the shade tolerant species like Acer mono ant Ligustrum obtusifolium, the growth performances were better in the seedlings grown in 38-62% light intensities of full sun. Total dry mass including the dry mass of leaves, shoot and root were as a whole decreased with shade treatment. The ratio of the dry mass of leaves and stem increased the dry mass of root. T/R ratio of the seedlings increased by decreasing the relative light intensity. And the T/R ratio of 2-6% light intensities of full sun was ranged from 1.1~5.0 were greater in the full sun light was ranged from 0.6~3.2. Light intensity by artificial shade treatment decreased in deciduous trees when compared on the whole, it showed tendency that SLA increases, increased that seeing resemblant tendency in LAR and LWR and changed of light intensity is strong, it increased that showed difference as statistical. But, LWR of Betula platyphylla var. japonica increased gradually and showed tendency that decreases rapidly in the shade treatment of 2-6% light intensities of full sun. This result is thought that biomass production decreased by shading treatment influenced in physiological characteristics such as leaf area and decrease of the leaf amount.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.52-58
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• 2011

In order to investigate an artificially transition method of perennial ryegrass(Lolium perenne L. 'Accent') overseeded on zoysiagrass (Zoysia japonca Zenith') with Kerb (3,5-jichloro-N (1,1-dimethyl-2-propynyl). We observed turfgrass growth and physiological responses of the two turfgrasses under the shading treatments. The experiment was conducted in greenhouse during April- August. Shading was generally using a black shade net product whose the shade level was done into 0, 35 and 75%, actual light intensities were 589, 378 and $135\;{\mu}mol{\cdot}m^{-2}{\cdot}s$ PAR, respectively. The four levels of Kerb treatment were 0, 0.1 0.2, and $0.4\;g{\cdot}m^{-2}$. As shading was getting increased, growth of perennial ryegrass was increased slowly, but zoysiagrass was reduced and almost all of experiments showed significant differences statistically. Perennial ryegrass exhibited inclination that growth was reduced in more than Kerb $0.4\;g{\cdot}m^{-2}$ by shades. On the other hand, it was shown that the growth of zoysigrass was reduced by shades largely and it was not effected by Kerb. Through this study, it was determined that Kerb is effective for elimination of overseeded perennial ryegrass on zoysiagrass. Moreover, when excluding perennial ryegrass under the condition like shade, it is desirable for treating high concentration more than the basic processing amount.

• The Korean Journal of Ecology
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• v.1 no.2
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• pp.57-65
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• 1977

The biomass and net production of alder and oak trees was estimated by allometric method. The productivity of the two stands of alder and oak was obviously different judging from the rate of photosynthesis productive structure and vertical distribution of light. The amounts of net photosynthesis under the saturated light were 2.31, 1.42mg $CO_2/dm^2\cdot$hr. in the sun and shade leaves of alder tree and 1.58, 0.84mg $CO_2/dm^2\cdot$hr in that of the oak, respectively. Total annual respiration loss calculated from the respiration measured at $25^{\circ}C$ and the mean air temperature from every 10 days were 13.56ton/ha.yr in the alder stand and 19.83 ton/ha.yr in the oak. The productive structure and the vertical distribution of light in the stand were assumedly more effective to produce dry matter in the oak stand than in the alder. The biiomasses measured in 1975 and 1976 were 51.51 and 56.82 ton/ha in the alder stand and 73.35, 86.77 ton/ha in the oak one, respectively. Annual net production and gross production were 8.56 and 22.12 ton/ha.yr in the alder stand but those were 17.90 and 37.74 ton/ha.yr in the oak stand. The ratios of respiration to gross procution (R/Pg) were prespectively 0.61 and 0.53 inthe alder and oak stands. Efficiencies of solar energy utilizaztion of net production during the growing season(May-Oct.) were 0.67 and 1.40% and those of gross production were 1.72 and 2.94% in the alder and oak stands respectively.