• Journal of Bio-Environment Control
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• v.30 no.3
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• pp.183-187
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• 2021

Appropriate pruning is very important for southern highbush blueberries cultivated in a heated plastic house to control their severe crowding within the bush canopy after harvest. Pruning treatments at different times were evaluated to find out an appropriate pruning time to southern highbush 'Scintilla' cultivation with heating. Seven-year-old (2018) bushes, grown in 180-L containers, were summer-pruned on May 20 (35-39 days after harvest) and June 20, or dormant-pruned on December 20 (5 days before flowering), consecutively in both 2018 and 2019 removing 30% of the total woods. May pruning activated occurrence of shoots the following years, increasing number of shoot by 17 to 49% and total shoot length by 18 to 32% compared with those of the dormant pruning. Fruit characteristic was not significantly affected by different pruning times the previous year. The first year pruning treatment did not influence the yield the following year, but the second year consecutive May pruning significantly increased yield per bush by 7% compared with the dormant pruning. The results indicated that summer pruning in May could be favorable to promote shoot growth and to maintain stable yield.

• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.15-22
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• 2023

Roses are one of the most produced flower species in the world, and cut roses are produced in the greenhouses all year round. Recently, due to the increase in the temperature in the greenhouses in summer, the quality of cut roses is seriously deteriorated, such as shortening the stem length. This study was conducted to investigate the effects of the growing seasons on the qualities of cut roses and also to test the effect of cooling at night in high temperature season on the cut flower qualities of roses. Comparing the qualities and yields of cut roses for each season, the major cut flower qualities such as flower stem length, stem diameter and fresh weight were statistically significantly decreased in roses ('Pink Beauty' and 'Pink Shine') produced in summer. The yields didn't show a statistically significant difference in both cultivars. Investigating the cut flower qualities, the flower stem length increased by 15% for 'Pink Beauty', 11% for 'Ararat', and 12% for 'Pink Shine' when treated with cooling at night in warm season than the untreated control. In addition, when treated with cooling at night in warm season, the fresh weight of all three cultivars increased by 20-30% statistically significantly than conventionally cultivated control. It is expected that cooling at night in warm season will be helpful to improve the cut flower quality deterioration in summer.

• Journal of Environmental Science International
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• v.20 no.4
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• pp.465-482
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• 2011

To preserve atmospheric environment of urban areas, it needs to create urban space considering air pollution sources and natural and geographical properties such as wind circulation. According to this study could examine climate and environmental characteristics of Daegu and accordingly suggest a climate map in urban environment and an "advice map" in urban planning. The urban area(area paved with asphalt and concrete) of Daegu has increased by more than five times since 1960. In addition, the analysis of thermal environment through satellite data shows that the surface temperature between a place paved with artificial structures and a farmland shows $10{\sim}20^{\circ}C$ difference during the daytime in the summer. Regarding the parks inhibiting the heat island of a city have the small area of trees, and the road paved with concrete is wide so that they hardly serve as the source of heat absorption. As Apsan is located to the south of Daegu and Palgonsan to the north and Daegu has east high west low type, mountain wind from mountains in the south and north passes a city and delivers heat and air pollutions at night. In the west of Daegue, there is the poorest environment and industrial facilities and environmental basic facilities are mostly located, so large residential complexes that are being built around the industrial facilities as if they set up a folding screen and therefore the poor environment is increasingly worse.

• Journal of Korean Society on Water Environment
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• v.37 no.2
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• pp.114-127
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• 2021

Water pollution in the lower reaches of the Namhan River is getting worse due to drought and a decrease in water quantity due to climatic changes and hence is affecting the water quality of Paldang Lake. Accordingly, we have used a water quality index (WQI) and statistical analysis in this study to identify the characteristics of the water quality in the lower reaches of the Namhan River, the main causes of water pollution, and tributaries that need priority management. Typically, 10 items (WT, pH, EC, DO, BOD, COD, SS, T-N, T-P, and TOC) were used as the water quality factors for the statistical analysis, and the matrix of data was set as 324 × 10·1. The correlation analysis demonstrated a strong correlation between Chemical Oxygen Demand (COD) and T-P with a high statistical significance (r=0.700, p<0.01). Furthermore, the result of principal component analysis (PCA) revealed that the main factors affecting the change in water quality were T-P and organic substances introduced into the water by rainfall. Based on the Mann-Kendall test, a statistically significant increase in pH was observed in SH-1, DL, SH-2, CM, and BH, along with an increase in WQI in SH-2 and SM. BH was identified as a tributary that needs priority management in the lower reaches of the Namhan River, with a "Somewhat poor" (IV) grade in T-P, "Fair" grade in WQI, and "Marginal" grade in summer.

• Korea Science and Art Forum
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• v.36
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• pp.11-22
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• 2018

This study recent changes in urban thermal environment caused by climate change generate diverse problems such as urban heat island effects, heat wave, and drought. Under this condition, with the increased perception and expectation of the quality of life, the urban citizens' desire for outdoor activities is increasing. This study conducted the thermal environment analysis focusing on the urban ecological park used by many urban citizens, and also suggested the renovation measures for urban ecological park considering the thermal environment. As the research site, the ecologically-favorable Gildong Ecological Pak with diverse space composition was selected. The measuring items were measured and analyzed by dividing them into thermal environment index and thermal comfort index. In the results of analysis in each type of park space, the forest zone showed the most favorable result. Based on such results, total three kinds of renovation measures for urban ecological park considering the thermal environment were suggested. Through this, the urban ecology park renovation plans were presented in three ways. The results of this study are meaningful in that it can be used as a base material for creating an ecological park considering the thermal environment.

• Journal of Environmental Science International
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• v.32 no.6
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• pp.403-417
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• 2023

In this study, we investigated the characteristics of Volatile Organic Compounds(VOCs) emission from painting and printing facilities in the Pyeongdong industrial complex in Gwangju. In addition, the objective was to understand the distribution characteristics of VOCs in the ambient air in industrial complexes affected by painting and printing facilities. The painting facility mainly emitted toluene, acetone, butyl acetate, 4-methyl-2-pentanone, ethyl acetate, 1-butanol, methyl ethyl ketone, m,p-xylene, o-xylene, 4-ethyltoluene, ethylbenzene, 3-ethyltoluene, and 1,2,4-trimethylbenzene. The main emission components in printing facilities were methyl ketone, ethyl acetate, acetone, 2-propanol, toluene, heptane, and butyl acetate. Ethyl acetate, toluene, 2-butanone, acetone, butyl acetate, 2-propanol, xylenes, and 4-methyl-2-pentanone were detected in the ambient air of the Pyeongdong industrial complex, consistent with the VOCs emitted by painting and printing facilities. The average concentration of seasonal TVOCs followed an order of winter > fall > spring > summer, whereas the concentrations of daytime and nighttime TVOCs were generally higher at night than those during the day, and the wind speed was greater during the day than it was at night. Based on a factor analysis of VOCs in the ambient air of Pyeongdong industrial complex, it is considered that organic solvents used in coating, printing, and electronics manufacturing facilities, as well as diesel vehicle emissions played a major role.

• Horticultural Science & Technology
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• v.35 no.3
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• pp.361-372
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• 2017

Bred and grown around the world, tomato (Solanum spp.) has highly valuable fruits containings various anti-oxidants such as lycopene, flavonoids, glutamine, and ${\beta}-carotene$. Several studies have explored, way in which to enhance the growth, management and quality of tomato, we focus on the management of growth for yield rather than quality. The expression of superior agronomic traits depends on where cultivars are grown. We evaluated 10 cultivars grown in three environment for their lycopene. HTL3137 ($70.48mg{\cdot}kg^{-1}$), which was grown in Yoeju in spring/summer, contained the highest lycopene content, while HTL10256 ($20.9mg{\cdot}kg^{-1}$), which was grown in Suwon in spring/summer, contain the least lycopene.Correlations between color components and lycopene content varied according to growing location and season. In spring/summer-grown tomatoes from Suwon, no significant correlation was observed between any color component (redness [R], greenness [G], blueness [B], luminosity, $L^*$, $a^*$, $b^*$, hue and chroma) and lycopene content. A correlation was observed between B and lycopene content in tomatoes grown in Yeoju during the same season. In tomatoes grown in Yeoju in fall/winter, significant correlations were found between lycopene content and G, luminosity, $L^*$, and hue. Variance in interactions between genotype, environment, and genotype ${\times}$ environment (G ${\times}$ E) using Minimum Norm Quadratic Unbiased Estimate (MINQUE) analysis indicated that lycopene content depends on genotype (51.33%), environment (49.13%), and G ${\times}$ E (21.43%). However, when the Additive Main Effects and Multiplicative Interaction (AMMI) was used, the G ${\times}$ E value was highest.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.5
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• pp.491-503
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• 2014

This study was performed to investigate the community structure and health assessment of macrobenthic assemblages in Garorim Bay, West Coast of Korea. Macrobenthos were collected by van Veen grab sampler at May(spring) and July(summer) 2012. A total of 247 species occurred and mean density was $1,625\;ind.\;m^{-2}$, both of which were dominated by annelid polychaetes(120 species and $1,241m^{-2}$). Dominant species were the polychaetes Ampharete arctica, Lumbrineris longifolia, Mediomastus californiensis and Euclymene oerstedi, with a density of 445(${\pm}1,837\;ind.\;m^{-2}$), 103(${\pm}148\;ind.\;m^{-2}$), 55(${\pm}83\;ind.\;m^{-2}$) and 50(${\pm}104\;ind.\;m^{-2}$), respectively. The study area was divided into 3 station group based on the cluster analysis and nMDS ordination. These assemblage were : 1)the group 1 and 2 were associated with coarse sediment dominated stations and 2)the group 3 was connected with a mixed and fine sediment dominated stations group. The BPI and AMBI index were applied to assess the benthic ecological status. The ecological status of the Garorim Bay was "good status(slightly polluted)" to "high status(normal)" at most sampling stations during spring and summer. In conclusion, the two marine biotic index calculated shown that the Garorim Bay had a good ecological status.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.4
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• pp.372-380
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• 2015

In order to study the characteristics of physical environment in water column around the artificial upwelling structure, CTD and currents measurements were carried out along line observations. Before installation of artificial upwelling structure was installed, the stratification of water column existed 30m in water depth. After installation of artificial upwelling structure, however, stratification formation depth and strength changed depending on currents directions. It seems that the change of stratification has a close relation with upwelling of lower temperature water. After installing the artificial upwelling structure, the distributions of vertical flows were analyzed. Local upwelling and downwelling flows showed a distinct time and spacial changes. Local upwelling flows caused by artificial upwelling structure appeared 100 times larger than coastal upwelling in the South-East Sea of Korea. Upwelling flows generated by the artificial structure raised the high concentration of nutrients to upper layer from lower layer breaking stratification in the summer. Thus, upwelling structure plays an important role for vertical water circulation improving the food environments by increasing primary production.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.4
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• pp.193-202
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• 1998

Water quality of Masan-Jinhae Bay was monitored from January 1996 to August 1997. The monitoring focused on the spatial and vertical gradients and seasonal changes of eutrophication parameters such as nutrients, DO and water transparency. Flagellate phytoplanktons persistently bloomed from April to October with monospecific or mixed algal blooms and dynamic algal successions were observed in this area. Algal blooms were highly correlated with salinity drops and made the water less transparent. Stratification of oxygen content was persistent through summer and oligo-oxygenation was developed in the bottom waters. Nutrient gradients were consistently maintained through the depth in summer and through spatial distribution from inner Masan Bay to outer Jinhae Bay in winter. Except the rainfall seasons, water quality was under the influence of the waste waters discharged from watershed around the Masan Bay. The waste waters would act as the primary factor for the water quality deterioration of the bay. Literature data for eutrophication were gathered and analyzed to review the water quality trends of the Masan and Jinhae bays since 1970. Annual mean COD and phosphate concentration consistently increased from 1975 to 1990 and decreased or dropped after 1991. The sediment of inner part of Masan Bay was dredged from 1991 to 1994 as a decontamination process and it is assumed that the dredging has weakened more or less the deterioration trend of the water quality of the bay.