• Korean Journal of Organic Agriculture
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• v.7 no.2
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• pp.125-151
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• 1999

After the release of facts that the high nitrate contents in vegetables by Korean organic farming, organic farmers were recommended by Korean Organic Farmer Association to apply 20t/ha compost while they applied before as much as they could, sometimes even more than 100t/ha. This study was aimed to check the safety of Korean organic product in terms of nitrate content. Current nitrate content in leaf and root vegetables by 3 different farming systems(organic farming, conventional farming, greenhouse farming) were monitored and furthermore it was compared with previously published another data in Korea to find out any changes among the monitored years(1993-1999). Current nitrate content in chinese cabbage, lettuce and kale became less compare to those of the beginning of monitoring, and especially those cultivated organic farming got the lowest value while previous organic vegetables at beginning of 90's showed the higher value than those cultivated in greenhouse. This decrease in organic vegetables was affected by less application rate of organic fertilizer than before at 20t/ha. But the nitrate level by organic farming was still higher compare to those cultivated by conventional farming in open field, since currently monitored organic vegetables were cultivated basically in greenhouse condition. It shows the organic farmer the necessity of transfer their farming site and condition from greenhouse to open field in order to decrease of its high level of nitrate caused long-term application and slow release characteristics of organic fertilizer. It was concluded the adoption of soil nitrate test to recommend a organic farmer the exact application rate for need of crop growth. Additionally the mechanism of lower nitrate accumulation in rice and fruit vegetables were also discussed in the paper.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.343-346
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• 2003

A heating greenhouse early in Joseon Dynasty was restored to the estimated state by the document "sangayorok(1940)" Diagrams of a restored greenhouse was reported. This heating greenhouse is eldest in the world. Growing vegetables in a restored greenhouse the inner temperature and humidity was investigated. This greenhouse was identified as making grow possible.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.359-364
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• 2005

Comparison of pesticide residue dissipation in/on cucurbitaceous fruit vegetables applied by foliar spraying under greenhouse was carried out to give information on crop grouping for assessment of pesticide risk. Even though the initial deposit of spayed pesticide on the target vegetables were somewhat different from the varieties, the dissipation patterns of the residues gave a similar tendency. In case sub-groupings of cucurbitaceous fruit vegetables are carefully arranged, the residue data among the vegetables are able to be taken for pre-harvest interval (PHI) settings or food safety assessment.

• The Korean Journal of Mycology
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• v.41 no.4
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• pp.212-217
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• 2013

Unusual mushrooms were observed in the greenhouses of vegetables Chinese chive, cucumber, melon and Korean dandelion in four locations of Korea in 2012. The mushrooms usually grew with the vegetables cultivated on beds in the greenhouses. Occurrence aspects of the mushrooms in the greenhouses and effect of the mushrooms on growth and quality of the vegetables were investigated. Mushroom samples were collected from the beds in the greenhouses and identified based on their morphological characteristics. The mushroom samples collected from the greenhouse of Chinese chive were identified as Coprinus aokii, those from the greenhouse of cucumber as Cristinia eichleri and Coprinus sp., those from the greenhouse of melon as Leucocoprinus cretaceous, Panaeolus fimicola and Conocybe sp., and those from the greenhouse of Korean dandelion as Conocybe rickenii f. tetrasporique. Out of the seven mushrooms identified, L. cretaceus, C. rickenii and C. eichleri were first found in Korea. The investigation results revealed that the mushrooms were originated from compost or soil used in the beds, and showed that C. aokii caused sooty mold on leaves of Chinese chive, and C. rickenii f. tetrasporique hindered growth of Korean dandelion and caused sooty mold on leaves of the plant. The other mushrooms had no effect on growth and quality of the vegetables.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.317-323
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• 2013

This research was conducted to obtain the basic information for establishment of standard guidelines in the design and installation of roof ventilation system in single-span plastic greenhouse. To achieve this, the greenhouse structure & characteristics, cultivation status, and ventilation system were investigated for single-span greenhouse with roof ventilation system cultivating the Cucurbitaceae vegetables, watermelon, cucumber, and oriental melon. Most of single-span watermelon greenhouse in Haman and Buyeo area were a hoop-style and the ventilation system in those greenhouses mostly consisted of two different types of 'roof vent (circular or chimney type) + side vent (hole) + fan' and 'roof vent (circular type) + side vent (hole or roll-up type)'. The diameter of circular and chimney-type vent was mostly 60cm and the average number of vents was 10.5 per a bay with vent spacing of average 6.75m. The ratio of roof vent area to floor area and side vent area in the single-span watermelon greenhouse with ventilation fan were 0.46% and 7.6%, respectively. The single-span cucumber greenhouse in Haman and Changnyeong area were a gable roof type, such as even span, half span, three quarter and the 70.6% of total investigated single-span greenhouses was equipped with a roof ventilation fan while 58.8% had a circulation fan inside the greenhouse. The ratios of roof vent area to floor area in the single-span cucumber greenhouse ranged from 0.61 to 0.96% and in the case of the square roof vent, were higher than that of the circular type vent. On average, the roof ventilation fan in single-span cucumber greenhouse was equipped with the power input of 210W and maximum air volume of $85.0m^3/min$, and the number of fans was 9.75 per a bay. The number of roof vent of single-span oriental melon greenhouse with only roll-up type side vent ranged from 8 to 21 (average 14.8), which was higher than that of other Cucurbitaceae vegetables while the vent number of the greenhouse with a roof ventilation fan was average 7 per a bay.

• Current Research on Agriculture and Life Sciences
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• v.31 no.4
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• pp.280-285
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• 2013

This study supplies basic data to develop a greenhouse model for reducing the damage to single-span greenhouses caused by strong winds and heavy snow. Single-span plastic greenhouses are predominantly used for growing crops in Korea. Thus, the safety wind speeds for single-span greenhouses were calculated and compared with the actual wind speeds and snow depths over a period of 8 years in different regions to analyze the structural safety of single-span greenhouses. The unit wind load and unit snow load were applied to different designs of single-span greenhouse according to the cultivated crop to achieve a structural analysis. As a result, the maximum section force for the wind and snow load was greatest for leaf and root vegetables, where the safety wind speeds for single-span greenhouses according to the cultivated crop were 17.7 m/s(leaf vegetables), 20.2 m/s (fruit vegetables), and 22.3 m/s (root vegetables). Thus, the single-span greenhouses were not found to be safe for the wind load in most regions, except for Hongcheon, Icheon and Sungju. Plus, the safety snow depths for single-span greenhouses according to the crop were 8.8 cm (leaf vegetables), 9.4 cm (fruit vegetables), and 11.8cm (root vegetables). Thus, when comparing the safety snow depths with the actual snow depths, the single-span greenhouses were not found to be safe. Therefore, to improve the safety of single-span greenhouses, the structures need reinforcement by reducing the interval between rafters or increasing the size of the pipes. However, additional research is needed.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.1
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• pp.49-61
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• 2008

The objective of this study is to survey the risk factors of greenhouse vegetables farmers' work-related musculoskeletal disorders(MSDs). To offer the fundamental data for agricultural improvement of greenhouse vegetable farms, the questionnaire of MSDs and heath condition were carried out. A group of 736 workers(males=492, females=244) in 6 branches constitutes the population and database for the analysis between 2004 and 2005. The sample branch was chosen based on paper are watermelon, strawberry, tomato, melon, cucumber, lettuce. The results are as follows: 1. Smoking rates in cucumber and tomato is the highest. 2. Drinking rates in strawberry, cucumber and lettuce is the highest in males, watermelon and melon are the highest in females. 3. Regular exercise rates in melon are the highest. 4. Physical and mental fatigue in females is higher than that of males in most crops except melon. That of strawberry and tomato is the highest. 5. The prevalence rates of medical diagnosed diseases are higher in order of osteoarthritis, herniated nucleus pulposus(HNP), and hypertension. That of strawberry, melon, and cucumber is high in case of osteoarthritis; Strawberry, melon, and watermelon are high in case of HNP. 6. Prevalence rates of musculoskeletal symptoms among the various pain areas are higher in order of low back, knees, and shoulders. That of tomato and watermelon is high in case of low back; strawberry and tomato are high in case of knees. These results can be used practically for agricultural improvement of greenhouse vegetables farms to prevent MSDs.

• Proceedings of the Korean Society of Crop Science Conference
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• 1998.10a
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• pp.41-67
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• 1998

This study aimed at examining the investment and economic analysis of greenhouse horticultural project area by governmental subsidy project. There were only 5 project areas that economic efficiency of investment is recognized in 30 project area in Kyungsangnam-do. And there are 7 project areas to gain farm firm revenue. These were possible area to develop to farm firm. There are 4 project areas to gain farm firm revenue in 18 project areas of glass greenhouse area, and 8 project areas to gain farm firm revenue in 12 project areas-vinyl greenhouse area. The rate of return of the fixed capital is higher in the vinyl greenhouse area than in the glass greenhouse area by type of greenhouse. There were cultivated tomatoes, cucumbers, peppers, etc. in the greenhouse area. The investment efficiency of the fixed capital is higher in cucumber and pepper than in other vegetables. Flowers a re lower than the vegetable in investment efficiency.

• Korean Journal of Environmental Agriculture
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• v.42 no.3
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• pp.193-202
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• 2023

Residue monitoring of propiconazole (PCZ) in cabbage, shallot, and spinach was conducted under multi-trial greenhouse conditions. This study aimed to understand the fate of the applied fungicide in these vegetables. Furthermore, the associated health risk of PCZ in leafy vegetables was assessed through dietary risk assessment. Commercially available PCZ (22% suspension concentrate) was administered thrice according to the OECD fungicide application interval guideline. The plant samples were extracted using a slightly modified QuEChERS technique and analyzed using gas chromatography-tandem mass spectrometry. The average PCZ recovery was between 84.5% and 117.6%, with a <5% coefficient of variance. The dissipation of PCZ residue in cabbage, shallot, and spinach after 14 days was 96%, 90%, and 99%, respectively, with half-lives of <5 days. Meanwhile, dietary risk assessments of PCZ residues in the studied vegetables using the risk quotient (RQ) were significant < 100 (RQ < 100). Thus, the population groups considered in this study were not at substantial risk from consuming leafy vegetables sprayed with PCZ following critical, good agricultural practices.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.173-184
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• 2012

The objectives of this study are to analyze the factors affecting the structural changes of agricultural land use in Gyeongsangnam-do and to prospect for its future use. Seven commodity groups are categorized to include all agricultural products: rice, summer food crops, summer vegetables and other cash crops, fruits, barley, winter field vegetables, and winter greenhouse vegetables. We developed a model for acreage distribution among the seven commodity groups, and estimated the economic relations between prices and acreage distribution. The results showed positive relations exist between cultivating acreage and own commodity prices in all commodity groups, whereas competitive relations exist between summer commodity groups or winter commodity groups such that rice price decreases led to increases of fruits cultivating acreage or vice versa and winter vegetable price increases led to increases of winter greenhouse vegetables cultivating acreage or vice versa. Further, acreage elasticities with respect to own commodity prices or farm wage rates are estimated over the last 30 years, and future agricultural land use in Gyeongsangnam-do is prospected based on three different scenarios. Total agricultural land use in Gyeongsangnam-do will be decreased over the next 10 years from 159,000 ha in year 2010 to 143,000~153,000 ha in year 2020. By commodity group, cultivating acreage of rice, summer food crops, and barley will be decreased while cultivating acreage of summer vegetables, fruits, winter field vegetables, and winter greenhouse vegetables will be stagnant.