• Journal of Bio-Environment Control
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• v.4 no.2
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• pp.211-222
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• 1995

This experiments were carried out to investigate the growth responses of spinach to temperature controlling by shading treatments at different times during the summer, and the effects of environmental parameters on the growth and yield were evaluated. The fourth cultivation was showed maximum temperature at air temperature of 33.1$^{\circ}C$ and soil temperature of 28.6$^{\circ}C$, followed by third, second, fifth and first cultivation. Among the tested temperature decreasing by shading, shading with silver - coated PE film strips was the most effective in lowering greenhouse air temperatures by showing 1.1$^{\circ}C$ decrease as compared to the outside air temperature and 3.1$^{\circ}C$ decrease as compared to the air temperatures inside the non-shaded PE house and 2.3$^{\circ}C$ decrease as compared to the air temperaturese shading with black- coated PE film strips, the soil temperature was showing 2$^{\circ}C$ decrease in both shading treatments than non-shaded PE and outdoor. In first cultivation, difficult cultivated as compared to others period owing to bolting of spinach. This first period was cultivated used two domestic cultivars and six imported cultivars, significantly better growth and higher yield of spinach were recorded in glory, manchuparuk and sunlighr cultivars. The effectiveness of shading on spinach, as expressed by the crop yield increase, was the highest in the planting from July 1 to August 24.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.1
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• pp.99-106
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• 2006

Aircraft measurements have been executed for the purpose of monitoring the long range transported air pollution and estimation of air pollutant in/out-flux over the Yellow sea. Total 74 missions of measurements have been done since 1997, mainly in spring and fall. The main study domain was over $124^{\circ}$E $/sim$ $124^{\circ}$E, $35^{\circ}$N $/sim$ $37^{\circ}$N below 3,000m. In long-term trends, mixing ratios of $SO_{2}$N were around 2 ppbv expect in summer ( < 1 ppbv). NOx exhibited 24 ppbv and have no clear annual trends over the Yellow Sea. The concentrations of 03 were 51, 58, 41 ppbv in spring, summer and fall-winter, respectively. Backward trajectory was performed for three days to investigate the source regions of the air mass. Six regions were divided around Korea peninsular centering at $36^{\circ}$N, $126^{\circ}$E. I, II, III, IV and V regions represents in sequence northeast China and Siberia, Sandong peninsula and Balhae gulf, Sanghi and southern China, the south Pacific included Jeju island and the East sea included Japan. L region correspond to the airmass from Korea peninsula. Influx of $SO_{2}$N was approximately five times higher than outflux in yearly flux variation and showed a decreasing long-term trend since 1998. NOx outflux was average 0.095 ton/km/hr and three times higher than $SO_{2}$ outflux. In/out flux of 03 showed even distribution in yearly basis except 2002 (influx 5.45 ton/km/hr). The transported amounts from I, II, III regions were much higher than those from other region. In seasonal flux variation, influx levels of gas phases were the lowest in summer and the levels gradually increased from fall toward spring. As a result, transport of pollutants begins from fall and prevails in winter and spring.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.270-276
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• 2006

This experiment was conducted to selecting of oriental melon cultivars suitable for second cropping at summer season. At 20 days after transplanting, 'Supergumssaragi' and 'Gumhwangeunchun' were rapidly growing. Chlorophyll contents of 'Gumgigaeeunchun', 'Gumnodazieunchun', 'Gonggongcheelkkul' and 'Gumboddari' were higher than other cultivars. Days required from transplanting to harvesting of 'Gumboddari', 'Gumdongieunchun', 'Gonggongcheelkkul' and 'Gumgaeeunchun', 'Gumbora' and 'Supergumssaragi', 'Gumssaragieunchun', 'Gumnodazieunchun', 'Gummieunchun' and 'Gumhwangeunchun', 'Diamond' were 51, 52, 53, 55, 56 and 60 days, respectively. The fruit weigh tended to heavy in 'Supergumssaragi' and 'Gumgigaeeunchun'. The flesh thickness was thick a little in 'Gumgigaeeunchun'. The hardness tended to high in 'Gumgigaeeunchun', 'Gumnodazieunchun' and 'Gumgaeeunchun', but it was not difference between treatments. 'L', 'a', 'b' and Y.I. value of the fruit were not difference between the cultivars, but 'a' value was the highest at 'Gumgigaeeunchun', The yield per ha of 'Gumgaeeunchun' and 'Gumgigaeeunchun' increased 8%, 2% than 'Gumssaragieunchun', respectively. From above result, 'Gumgigaeeunchun', 'Gumdongieunchun', 'Gumnodazieunchun' and 'Gumgaeeunchun' cultivars are suitable in summer season.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.347-353
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• 2017

In this study, numerical experiments were conducted to identify distribution of rising flow and flux in the East Sea of Korea, where the coastal upwelling occurs. Temperature and salinity data from CTD observations and NIFS during summer 2013 were applied to the model. Numerical experiments were carried out with different wind speed (3, 6 m/s and 9 m/s) and direction (southerly and southwesterly), which represent the most frequent in summer conditions. As a result of calculation, upwelling flow rate was found to be highest in Pohang between five coasts(Hupo, Youngduk, Pohang, Ulsan and Busan). Comparing with southerly wind conditions, the rising flow rate is about 1.5 times greater when southwesterly wind was applied. Horizontal diffusion of the upwelling area is expected to have a speed of 17~22 km/day when a 9 m/s southwesterly wind is applied. If this wind continues over one week, a cold pool will be generated by upwelling that may reach to the Ulleung area.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.1
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• pp.1-10
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• 2011

To understand characteristics of the water quality on the coastal boundary on tidal flat, field observations between 2008 and 2009 were undertaken twice a month at five coastal areas (Muan bay, Tando bay, Hampyeong bay, Shinan Jido and Yeongkwang coastal areas). Yearly water temperature difference was large with the range between $1.3^{\circ}C$ and $31.1^{\circ}C$. Salinity was about 32 but was the lower less than 20 for the heavy rainfall season. DO was high in winter and low in summer according to the variation of water temperature. pH represented the variation similar to DO. Suspended solid was averagely high over 100 mg/l in Yeongkwang coastal area, especially. COD did not revealed large variation with the value of about 1 mg/l. DIN and DIP concentration were high when freshwater was highly input in summer. DIN concentration was low for winter and early spring but DIP concentration did not show the seasonal variation with the continuous increase from July 2009 to December 2009. Chlorophyll a appeared high for spring with approximately $10\;{\mu}g/l$ and was higher for summer in Yeongkwang coastal area than other sites. The results of principal component analysis conducted to compare the characteristics of water quality observed in study areas showed the distinguishable features as follows. The freshwater input fluctuation appeared as the first factor in Muan and Tando bays, and the change of water temperature was the first factor in Shinan Jido and Yeongkwang coastal areas. The influence mixed with the variation of freshwater outflow and the change of water temperature in Hampyeong bay was to be the first factor.

• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.183-192
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• 1995

This study was conducted to investigate bird community and to suggest a proper way how to manage and protect wildbirds in Chuwangsan National Park. The survey was carried out over two survey sections by the line transect method in spring, summer and autumn in 1994. Total number of observed birds were 42 species(33 species in spring, 32 species in summer, and 26 species in autumn), and the result was the same with the typical pattern of temperate bird communities. Total number of natural monument and rare birds were 7 species, which included Golden Eagle(Aquila chrysaetos), Chinese Sparrow Hawk(Accipter soloensis), Eagle Owl(Bubo bubo), etc. In breeding season, species richness was high in canopy nesting guild, and density(ea/ha) was high in hole nesting guild. Canopy foraging guild was dominated in spring and summer, ratio of bush(or ground) foraging guild was increased in autumn. Since the habitats of observed natural monuments and rare species were roughly overlapped with the nature preservation area, it is necessary to preserve the area completely and to investigate and protect these species continuously. For the protection of the bush(or ground) foraging guild, it needs to plant bushes around trails and to control users. Food plants, artificial food planting of bushs, and artificial nest are needed for the habituation of wildbirds, and as the damage of wild cats is increasing lately, it needs to control these cats.

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.286-292
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• 2010

Native oak tree species dominate the deciduous forests of South Korea. Although the acorns of these oak trees represent the main food source for many wildlife species, information pertaining to their nutrient composition and associated seasonal changes is limited. Thus, the objective of this study was to describe the seasonal changes in the acorn nutrient composition of six oak species in terms of nitrogen (N), phosphorus (P), calcium (Ca), magnesium (Mg), and sodium (Na) concentrations, Quercus acutissima, Q. aliena, Q. mongolica, Q. variabilis, Q. dentata, and Q. serrata. The results indicated that N concentrations of Q. aliena acorns were constant, whereas those of Q. dentata changed over the seasons. Those of Q. acutissima acorns were higher in summer and autumn but Q. mongolica acorns were higher in spring and summer. Q. serrata acorns were highest in autumn but Q. variabilis acorns were found to be the lowest in N concentration. P concentrations of acorns of six species tended to decline in the summer but increased in the spring and autumn. Ca and Mg concentrations showed an obvious trend of decline over the seasons for all species except Q. mongolica. Na concentrations of Q. aliena, Q. dentata, and Q. serrata acorns were constant over the seasons whereas those of Q. dentata tended to increase. Q. variabilis acorns were highest in autumn but Q. acutissima acorns were lowest in Na concentration. Overall, these results showed that acorn nutrient composition varies by season, and that the nature of the variability is largely species dependent.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.388-394
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• 2007

To product the edible fresh shoots of Sedum sarmentosum in summer season, 4 local strains were cultivated with cutting propagation under 0, 30, 50, 70, 90% shading. Effect of shading on shoot growth, leaf chroma value, SPAD value, and bitterness were investigated at 35 days after cutting. Plant height, the number of node and leaf stem diameter in $30{\sim}90%$ shading were increased than in the control, and Pohang local strain had little-overgrowth shoot, thicker stem, a few brenches per shoot, and larger leaf compared to the other local strains. Fresh and dry weight under shading were increased than in the control, dry weight of pohang local strain was highest in 50% shading. Hunter L and b values were decreased out of proportion to higher shading rate. SPAD value in $50{\sim}90%$ shading was significantly lower than in the control. The bitterness of fresh shoot was decreased out of proportion to higher shading rate. In Summer season, producing the fresh shoot of S. sarmentosum was excellent in 50% shading, and Pohang local strain among 4 local strains was more stable and good in yield and quality under shading.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.280-284
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• 2009

One of the big obstacles to cultivate asparagus was long days taking before first harvesting. This study was carried out to hasten the first harvesting of summer planted asparagus in Jeju. Seedlings were raised for three months and planted June 20th in green house. Harvesting of Spring were separated into non-harvested (control) and harvested (partly-harvesting, completely-harvesting). The first year we could harvest $399kg{\sim}400kg/10a$ in harvesting treatment. Second year's yield was 834kg/10a in partly-harvesting, 825kg/10a in completely-harvesting treatment and 908kg/10a in control. There is no significant difference in second years yield regardless of first year's harvesting methods. The accumulated total yield was increased by 35% (l,229kg/10a) in harvesting treatment from the first spring compared with the control. Marketable yield was increased by 33% (1,116kg/10a) compared with non harvesting in first year (839kg/10a). The result of this study shows that doing harvest of the first year's spring in summer planting asparagus would be desirable for yield and possible to harvest after 8 months planting.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.147-152
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• 2011

This study was conducted to evaluate the growth characteristics of creeping bentgrass cultivars for fairway of golf course at Yeoju area in Korea. At germination and coverage rate of creeping bentgrass, 'Shark' and 'CY-2' were excellent, 'L-93', 'Alpha', 'T-1 was in order', respectively. Visual qualities of 'Shark' and 'CY-2' also were excellent. Especially, 'Shark', 'T-1', and 'CY-2' showed excellent visual quality in summer days, the critical times for the bentgrass fairway quality. 'Shark', 'CY-2' and 'T-1' were excellent in Chlorophyll contents throughout the evaluation period. Chlorophyll content of 'T-1' was maintained very high in summer. 'CY-2' and 'Shark' showed the best root growth at the beginning of the study and contained longer and hairy roots. Which might make these two cultivars' water absorption easier than other's. NDVI (normalized difference vegetation index)of 'Shark', 'L-93' and 'CY-2' was excellent, respectively. 'T-1' showed the highest density and 'Shark', 'CY-2', 'Alpha', 'L-93' was followed by. The density of 'T-1' was rather increased in summer season, while those of other cultivars were decreased. Three diseases such as anthracnose, brown patch, and dollar spot, were appeared during the evaluation period. 'T-1' and 'L-93' were very sensitive to anthracnose which occurred at the beginning days of the study. The most susceptible cultivars to brown patch were 'Alpha' and 'L-93'. 'T-1' was the least resistant to dollar spot which occurred at the same time with brown patch.