• Korean Journal of Environmental Agriculture
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• v.3 no.2
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• pp.23-29
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• 1984

Agricultural soil samples collected from 121 sites (plastic film house 59, up-land 30 and orchard 32 sites) were evaluated by steam distillation and GLC-ECD analysis for organochlorine pesticides (${\gamma}-BHC$, heptachlor, p,p'-DDE, dieldrin, p,p'-DDD, and p,p'-DDT) in Jeollanam-Do area. Total residues of organochlorine pesticide in orchard, plastic film house and up-land were 0.415, 0.234 and 0.156ppm, respectively. Ninety-four percent of total residue was p,p'-DDT and its homologues (p,p'-DDE and p,p'-DDD). ${\gamma}-BHC$ was detected in all soil samples at $trace{\sim}0.050ppm$ range. Residue levels of organochlorine pesticide increased in the order of p,p'-DDE, ${\gamma}-BHC$, heptachlor, dieldrin, p,p'-DDT and p,p'-DDD.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.241-248
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• 1995

This experiment was conducted to obtain basic information for the management of soil and fertilization for plastic-house soil cultivated Khwari green pepper in Dang Jin area of Chung Nam Province. The range of pH with highest frequency for 36 sites investigated was 6.1~6.5, OM 1.6~2.5%, available phosphorous 601~800mg/kg, CEC 12.1~14.0 c mol/kg, clay 16.1~18.0% and below 2.0ds/m for electical conductivity of soil. Fesh fruit weight of green pepper showed very high significant positive correlation with organic matter, clay content and cation exchange capacity, while negaive correlation with electrical conductivity. Electrical conductivity showed highly significant negative correlation with CEC, clay content and organic matter in soil, respectively. To decrease below 2.0 dS/m of electrical conductivity in plastic-house soil, the content of clay and organic matter could be maintained at above 1.8% and 2.3%, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.72-76
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• 1998

In order to investigate the emission pattern of sulphur dioxide gas from the soils in the plastic film house, the amounts of sulphur dioxide gas emitted from soils was periodically measured either in the plastic film house condition or in the incubator where the interior temperature was controlled to 10, 20. 30 and $40^{\circ}C$. Each soil was mixed with either mushroom, poultry, pig or fish meal compost at the rate of 0, 10, 20, 30, 40 and 50g/kg for individual treatment and then treated with addition of 50, 100, 150 and 200ml of water. A significant increase in the emission of sulphur dioxide gas was observed in the treatment of fish meal compost and such increase was initiated from the rate of l0g/kg, while little difference was observed in other treatments. Compared to upland soils, as control, the horticultural soils containing higher sulphur content emitted more sulphur dioxide. The emission of sulphur dioxide was favoured as temperature increased and was highest with the addition of 150ml of water.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.697-706
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• 2022

The effect of varied light intensities on the growth of daughter plants during propagation and after transplant to raised beds were examined in 'Sulhyang' strawberry. To this end, four treatments in controlling solar radiation inside a plastic house were made: 55% retractable shading and 35, 55, and 75% fixed shading. The plastic house was shaded only from 11:00 to 16:00 in June and 10:00 to 16:00 in July to September for the treatment of 55% retractable shading. The mean solar radiation inside the plastic house in the retractable 55% shading treatment was 317 W·m^-2 and those in the 35, 55, and 75% fixed shading treatments were 183, 165, and 116 W·m^-2, respectively, at 10 o'clock in the morning. The 55% and 75% fixed shading resulted in taller daughter plants with wider leaf areas than 55% retractable shading. The retractable shading also showed higher leaf numbers, crown diameters, root weights, and fresh weights compared to fixed shading treatments. Regarding the inorganic element contents, daughter plants grown under 75% fixed shading had 1.35% total nitrogen content followed by 1.19% in 35% fixed shading, 1.14% in 55% fixed shading, 1.14% in open culture, and 1.10% in 55% fixed shading. After 54 days following the transplant of daughter plants to a raised bed, the fresh weight of the aboveground part was the heaviest in the 55% retractable shading and non-shading treatments. The 75% fixed shading treatment had the lowest fresh weight of the aboveground plant parts. The results of this study could be used for the production of high-quality daughter strawberry plants.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.200.2-200.2
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• 2010

This study was carried out in order to reduce the amount of underground water which is used in the water curtain system for retaining heat. To proceed to the research, two plastic green houses of water curtain system were installed. One was equipped of internal small tunnel for keeping warm air in the interior of the house. Then the internal small tunnel for keeping warm air was fitted with PVC duct of 50cm in diameter filled with subsurface water. Storing surplus solar energy in the water filled in PVC duct was the method used to this house. Another was installed with FCU in the middle of the house, and was fitted a circulation motor in water tank for heat storage which was operated from 10 a.m. to 4 p.m. in order to interchange heat with FCU. The latter was installed with four FCUs which has a capacity of 8000kcal per hour. Consequently about 5 degrees celsius could be maintained in the interior of the internal small tunnel for keeping warm air with the external temperature of more than minus 5 degrees celsius. It appeared that the alteration of an internal temperature of the house was flexible depending on the sunlight during daytime. It happened that to prevent the water from freezing, mixing antifreezing liquid in the flowing water of FCU or changing the operating method of FCU was a suitable measure. Also, in order to use the surplus solar thermal energy on plastic green house of water curtain system efficiently, storing the surplus heat during daytime simultaneously finding a method of using water curtain systematic underground water happened to be important. As a result of this research, when the house's interior temperature is below zero the operation of FCU appeared to be impossible. Therefore when supposed that the amount of water used in the house is 150~200ton for stable operation of FCU, using the system mentioned in the above research happened to be appropriate of reducing the amount of subsurface water from 80% to 100% when maintaining the interior of internal small tunnel's temperature for keeping warm air of 5 degrees celsius at the extreme temperature of minus 5 degrees celsius.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.45-54
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• 2014

The main purpose of this study is to provide the back-from-city farmers with the information about the melon cultivation technology by surveying 268 farm houses in the major melon producing districts such as Seongju and Chilgok. For the purpose, this study classifies the essential technologies that the melon experts think as most important into 6 categories: size of plastic film house, covering film, varieties of oriental melon, lagging cover, ventilation method and ways to reduce repeated-cultivation damage. The result of the study shows that the back-from-city farmers should consider the following items when they choose to cultivate oriental melons. For the size of plastic film house, the ventilation method and the covering film of plastic film house, it is better to choose the latest technology. Even though it may require larger initial investment, the latest technology can increase the production and lower the cost. In case of variety, it is better to choose popular or the most widely grown ones rather than the new ones. The lagging cover should be selected in consideration of climate conditions such as average temperature and humidity, transplant time and harvest time of the farming region.

• Journal of Environmental Science International
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• v.25 no.8
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• pp.1115-1129
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• 2016

To analyze human thermal environments in protected horticultural houses (plastic houses), human thermal sensations estimated using measured microclimatic data (air temperature, humidity, wind speed, and solar and terrestrial radiation) were compared between an outdoor area and two indoor plastic houses, a polyethylene (PE) house and a polycarbonate (PC) house. Measurements were carried out during the daytime in autumn, a transient season that exhibits human thermal environments ranging from neutral to very hot. The mean air temperature and absolute humidity of the houses were $14.6-16.8^{\circ}C$ (max. 22. $3^{\circ}C$) and $7.0-12.0g{\cdot}m^{-3}$ higher than those of the outdoor area, respectively. Solar (K) and terrestrial (L) radiation were compared directionally from the sky hemisphere (${\downarrow}$) and the ground hemisphere (${\uparrow}$). The mean $K{\downarrow}$ and $K{\uparrow}$ values for the houses were respectively $232.5-367.8W{\cdot}m^{-2}$ and $44.9-55.7W;{\cdot}m^{-2}$ lower than those in the outdoor area; the mean $L{\downarrow}$ and $L{\uparrow}$ values were respectively $150.4-182.3W{\cdot}m^{-2}$ and $30.5-33.9W{\cdot}m^{-2}$ higher than those in the outdoor area. Thus, L was revealed to be more influential on the greenhouse effect in the houses than K. Consequently, mean radiant temperature in the houses was higher than the outdoor area during the daytime from 10:45 to 14:15. As a result, mean human thermal sensation values in the PMV, PET, and UTCI of the houses were respectively $3.2-3.4^{\circ}C$ (max. $4.7^{\circ}C$), $15.2-16.4^{\circ}C$ (max. $23.7^{\circ}C$) and $13.6-15.4^{\circ}C$ (max. $22.3^{\circ}C$) higher than those in the outdoor area. The heat stress levels that were influenced by human thermal sensation were much higher in the houses (between hot and very hot) than in the outdoor (between neutral and warm). Further, the microclimatic component that most affected the human thermal sensation in the houses was air temperature that was primarily influenced by $L{\downarrow}$. Therefore, workers in the plastic houses could experience strong heat stresses, equal to hot or higher, when air temperature rose over $22^{\circ}C$ on clear autumn days.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.226-233
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• 1997

To investigate the salt accumulation in the plastic film house soils, bulk density, electrical conductivity(EC), exchangeable canons and water soluble anions were determined at different depths(0~60cm) in the salt-accumulated plastic film house soils in Yesan, Chungnam, Korea. Bulk density were increased from $1.2Mg/m^3$ to $1.5Mg/m^3$ as the depth changed from 0cm(top soil) to 30cm(subsoil) below the soil surface, whereas the bulk densities between 30cm to 60cm slightly decreased to $1.42Mg/m^3$. These changes of soil bulk densities might influence the porosity and pore size distribution, resulting in affecting the water flow throughout, soil layers. Electrical conductivity and Exchangeable sodium percentage(ESP) for 0 to 10cm soil layer were 5.08 dS/m and 6.4, respectively, while the EC was decreased to less than 1.63 dS/m in 20~30cm depth and about 0.7 dS/m. Salt accumulation patterns in the plastic film house soils might be influenced by the changes of the bulk densities in soil.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.153-157
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• 2003

This experiment was conducted to investigate control effect of Spodoptera litura using nucleopolyhedrovirus in chrysanthemum seedlings of open field and plastic house. Values of LT$_{50}$ of treatment 1.0$\times$10$^{6.8}$ PIBs/ml were 6.2-5.1 days in open field and 6.9-5.4 days in plastic house. Values of LT$_{50}$ and LT$_{95}$ were shorter in open field than in plastic house. Cumulative mortality was 100% in 1.0$\times$10$^{7.8}$ PIBs/ml and also higher in open field than in plastic house. In chrysanthemum field, organic synthetic insecticide (endosulfan EC) killed S. litura larvae in 2 days after application. Motality of S. litura larva inoculated with S. litura nucleopolyhedrovirus (SINPV) 1.0$\times$10$^{6.8}$ PIBs/ml was found out from 4 days after application and maintained during 14 days. Protection values of with SINPV 1.0$\times$10$^{8}$ PIBs/ml after 16 days were 94.0% and 89.4% in open field and plastic house, respectively, and those of endosulfan 350 ppm were 91.4% and 88.6%, respectively.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.223-227
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• 2003

Survey on plant diseases occurring on cucumber cultivated in plastic film house of experimental farm in Suwon was conducted. Through the survey, occurrence of damping-off, downey mildew, powdery mildew and Fusarium wilt was observed. Especially downey mildew caused by Pseudoperonospora cubensis was the most severe foliar disease of cucumber. To control the disease effectively, effects of installation of ventilation fan and optimal spray timing of a chemical, dimethomorph+copper oxychloride WP, were investigated. Two ventilation fans installed at the front and at the back of plastic film house reduced air relative humidity by about 6.4% and downey mildew incidence by 55.7%. Downey mildew incidence on cucumber from untreated chemicals plot in plastic film house installed with ventilation fan was on a equal level with that from treated chemicals plot with three times application of dimethomorph+copper oxychloride WP in plastic film house without ventilation fan. Meanwhile in order to select optimal chemical application time, dimethomorth+copper oxychloride WP was treated three times at 7 days-interval from three days before the disease occurred, right after the disease occurred, and two days after the disease occurred, respectively. The result showed that dimethomorth+copper oxychloride WP applied to cucumber leaves and stems from three days prior to, right after, two days after occurrence of downey mildew reduced downey mildew incidence by 72.9, 61.8, and 23.7%, respectively. The above results showed that regulation of environmental factors like air relative humidity and preventive application of chemicals should be considered to establish control strategy to downey mildew.