• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.305-311
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• 2016

In cultivation environment, various pesticides are used and some of them could be volatilized into the air. This could affect farmer's health and also cause environmental pollution. This study was carried out to investigate the volatilization of pesticides, and use the reference data for preventing farmer's pesticide intoxication and securing worker safety. The experiment was conducted in a greenhouse using a lysimeter which was of $1m^2$ area and 1.5 m depth filled with upland soil. The pesticides treated in lysimeter soil were ethoprophos (5.0% GR), diazinon (34.0% EC), alachlor (43.7% EC), metolachlor (40.0% EC), chlorpyrifos (2.0% GR), pendimethalin (31.7% EC), carbaryl (50.0% WP), napropamide (50% WP), tebuconazole (25.0% WP) and imidacloprid (2.0% GR). Each pesticide was treated at a concentration of 770.5 mg based on A.I (%). The recovery of pesticide ranged from 77.4 to 99.3%. The volatilized pesticides in air were collected by personal air sampler with PUF tube at 4 l/min flow rate. In addition, temperature and humidity were measured. The collected samples were extracted using acetone in a soxhlet apparatus for 8 hours. The extracted pesticides were resoluted with acetonitrile and diluted 5 times. It was analyzed with LC-MS/MS. For 720 hours experiment, the largest vaporization amount of each pesticide in air was ethoprophos $15.24{\mu}g/m^3$, diazinon $5.14{\mu}g/m^3$, pendimethalin $2.70{\mu}g/m^3$, chlorpyrifos $1.76{\mu}g/m^3$, alachlor $1.40{\mu}g/m^3$, metolachlor $1.12{\mu}g/m^3$, carbaryl $0.27{\mu}g/m^3$, napropamide $0.22{\mu}g/m^3$, tebuconazole $0.11{\mu}g/m^3$ and imidacloprid $0.05{\mu}g/m^3$. The R value (coefficient of correlation) between volatilization and vapor pressure of pesticides is higher than 0.99. Therefore, there is high correlation between volatilization and vapor pressure of pesticides.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.505-513
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• 2017

Objective: This study was performed to evaluate whether ambient temperature and dietary glycerol addition affect growth performance, and blood metabolic and immunological parameters, in beef cattle. Methods: Twenty Korean cattle steers ($405.1{\pm}7.11kg$ of body weight [BW], $14.2{\pm}0.15$ months of age) were divided into a conventional control diet group (n = 10) and a 2% glycerol- added group (n = 10). Steers were fed 1.6% BW of a concentrate diet and 0.75% BW of a timothy hay diet for 8 weeks (4 weeks from July 28th to August 26th and 4 weeks from August 27th to September 26th). Blood was collected four times on July 28th, August 11th, August 27th, and September 26th. Results: The maximum indoor ambient temperature-humidity index in August (75.8) was higher (p<0.001) than that in September (70.0), and in August was within the mild heat stress (HS) category range previously reported for dairy cattle. The average daily gain (ADG; p = 0.03) and feed efficiency (p<0.001) were higher in hotter August than in September. Glycerol addition did not affect ADG and feed efficiency. Neither month nor glycerol addition affected blood concentrations of cortisol, triglyceride, or non-esterified fatty acid. Blood concentrations of cholesterol, low-density lipoprotein, high-density lipoprotein, glucose, and albumin were lower (p<0.05) on August 27th than on September 26 th, and blood phosphorus, calcium and magnesium concentrations were also lower on August 27th than on September 27th. Glycerol addition did not affect these blood parameters. Percentages of $CD4^+$ T cells and $CD8^+$ T cells were higher (p<0.05) on July 28th than on August 27th and September 26th. The blood $CD8^+$ T cell population was lower in the glycerol supplemented-group compared to the control group on July 28th and August 27th. Conclusion: Korean cattle may not be significantly affected by mild HS, considering that growth performance of cattle was better in hotter conditions, although some changes in blood metabolic and mineral parameters were observed.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.182-186
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• 1998

The result of study on the morphological feature of fruitbody, soil characteristics and enviromental condition of habitat of Tricholoma giganteum in Korea was as follows: The Pileus was $5.5{\sim}28.0\;cm$ in diameter and $1.5{\sim}3.7\;cm$ in thickness, indicating of yellowish white, beige, or ivory color. The lamellae were $18{\sim}20\;mm$ in diameter; the stipe was $9.0{\sim}35.7\;cm$ long and $1.0{\sim}3.0\;cm$ wide. The spores were $3.5{\sim}4.8{\times}5.7{\sim}7.4\;{\mu}m$ in size, ellipsoid, hyaline and the spore deposit white. The basidia were $6.1{\sim}7.0{\times}32.2{\sim}39.2\;{\mu}m$ in size. Cheiloystidia were $3.5{\sim}4.4{\times}30.5{\sim}33.1\;{\mu}m$ in size. Pileipellis were $3.3{\sim}4.4{\times}33.0{\sim}55.0\;{\mu}m$ wide and had clamp connection. Stipitipellis were $2.2{\sim}3.3{\times}88.0{\sim}93.1\;{\mu}m$ in size. Texture of soil in habitate of T. giganteum was silty loam, and organic materials content and available phosphate content in this soil were high as comparision to general soil in Korea. In the time of the mushrooms sprout, the room temperature indicated $25{\sim}27^{\circ}C$, their humidity showed $80{\sim}83%$, and the brightnesses were 328 Lux.

• Food Science and Preservation
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• v.17 no.2
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• pp.190-195
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• 2010

Pressure, used as a minimal processing technology in the food industry, is a valuable tool ensuring microbiologically safe, shelf-stable fruit and vegetable production. Pressure could be used to deliver a greater variety of minimally processed products, as demanded by today's consumers. Weevaluated the effect of <400 MPa pressure, applied during chilling, on fresh fruit purees (strawberry, kiwi, aloe, and pomegranate) and vegetable extracts (from carrot and spinach) during cold storage (<$10^{\circ}C$) for 15-20 days. Samples were prepared in a processing facility in which total plate counts of falling and floating bacteria were controlled at $1{\times}100-10^1$ CFU/plate and $1{\times}10^2-10^3$ $CFU/m^3$ under conditions of $21-25^{\circ}C$ and 55-60% relative humidity. The aerobic plate counts of raw materials were less than $1{\times}10^3$ CFU/g. Evaluation parameters included microbiological safety, vitamin content, and sensory qualities. Although the overall quality of non-treated samples deteriorated with storage time at $10^{\circ}C$, samples pressurized at 250-350 MPa at $5-7^{\circ}C$ for 10 min showed less change, with no significant difference in microbiological safety, vitamin content, or sensory quality. The use of pressure extended the shelf-life during storage at $10^{\circ}C$.

• Korean journal of applied entomology
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• v.21 no.1 s.50
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• pp.38-48
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• 1982

This study was conducted to investigate the changes in moth occurrence of striped rice barer, Chilo suppressalis (Walker), in relation to climatic factors, rice varieties, and cultural practices. The light trap data from 41 forecasting stations for 14 years from 1966 to 1979 were analyzed by means of the changes in the time and amount of borer occurrence in connection with the introduction of new rice varieties, the accumulated effective day-degree and its variation for completing one generation, and the climatic factors affecting the moth occurrence. The total number of moths caught by light traps in both spring and summer generations were considerably decreased with the wide cultivation of new rice varieties. In fact, the spring moths were remarkably decreased since the new varieties were introduced in 1972. The occurrence ratio of summer moths against the preceeding spring moths was higher in the middle region and middle southern mountainous area than the other regions. Its high ratio of regions was annually expanded from the middle region to the southern region. The $50\%$ emergence dates of both generations were later in the southeastern region than in the middle region. The ecological characteristics were clearly shown between the northern and southern region of Chupungryeong in terms of the occurrence of summer moths, the ratio of occurrence of summer moths to the preceeding spring moths, and $50\%$ emergence dates of the summer moths during the years of $1977\~1979$. The ratio of the summer moth occurrence to the preceeding generation was negatively correlated with the average temperature in lune and July, respectively, and the average precipitation in late June. The ratio of spring moth occurrence over the preceeding generation was positively correlated with the average temperature in September, October, November, and March, respectively, whereas it was negatively correlated with the average precipitation in early September and March, and the average humidity in early May. The effective day-degree for one generation was in the range from 600 to 900 DD at upper threshold $30^{\circ}C$ and lower threshold $10^{\circ}C$.

• Asian Journal of Turfgrass Science
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• v.18 no.2
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• pp.63-70
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• 2004

This study was conducted to figure out the effect of 'Methlyen Urea(MU)', slow released fertilizer and 'T-Vigor', microbial fertilizer as environment fertilizer on growth of 'Crenshaw' creeping bentgrass for environmental management in golf course. This study was conducted at No. 3, 4, 5 Valley Courses of Rexfield Country Club from April to July in 2004. MU, T-Vigor, sterilized T-Vigor were applied five times with 5g and 7.5ml per square meter, respectively. Polt size was 1 square meter and there were three replications with Completely Randomize Design. Collecting data were turf density$(No.\;of\;shoot\;/cm^2)$, chlorophyll $amount(\%)$, root length(cm), dry weight of clipping(g), and dry weight of root(g). The results are as follows; All of turf density, chlorophyll amount and dry weight(g) of MU and T-Vigor were better than control and sterilized T-Vigor. Especially root length of MU and T-Vigor was superior to control and sterilized T-Vigor, even if temperature and humidity was high. In conclusion, MU and T-Vigor might be used as slow release fertilizer for environmental green management in golf course.

• Korean Journal of Environment and Ecology
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• v.30 no.4
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• pp.724-729
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• 2016

Environmental factors that affect the singing of cicadas have not been studied extensively, especially those affecting the cicadas' singing during the nighttime. Therefore, the objective of this study is to identify the effects of tropical night and light pollution on the cicadas' singing in a downtown area. The study sites were an apartment complex in Seocho-gu, Seoul, and the Chiaksan National Park in Wonju-si. The study subjects were Hyalessa fuscata and Cryptotympana atrata, which are the dominant species in Korea during summer. Cicada songs were recorded 24 hours a day, every day. The recording period was between July and August, lasting 25 days at the Seoul site and 14 days at the Chiaksan National Park. Temperature, precipitation, humidity, and amount of sunshine were selected as the environmental factors that potentially affect the cicadas' singing. Statistical analyses included correlations of meteorological factors with the cicadas' singing per hour, per 24 hours, and at nighttime (21:00~04:00). The results showed that: 1) H. fuscata began singing during the dawn hours, and the singing increased in intensity early in the morning. C. atrata's singing reached its peak in the morning and afternoon, ceased during sunset hours, thereby exhibiting a difference in the singing pattern of the two species. 2) The frequency of singing by H. fuscata decreased when C. atrata began to sing intensively in numbers, thereby exhibiting interspecific influence. 3) The results of the correlation analysis between meteorological factors and the singing of H. fuscata and C. atrata showed that both species tended to sing more when the temperature was higher and sang less on rainy days. 4) When limited to nighttime only, C. atrata showed a tendency of singing when the nighttime temperature was high ($24-30^{\circ}C$, average $27^{\circ}C$), whereas H. fuscata did not show a correlation with meteorological factors. However, since H. fuscata sang during the night in areas with artificial lighting, it was concluded that its singing was due to light pollution.

• Korean journal of applied entomology
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• v.55 no.1
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• pp.35-43
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• 2016

The temperature-dependent development of Metcalfa pruinosa overwintering eggs was investigated at ten constant temperatures (12.5, 15, 17.5, 20, 22.5, 25, 27.5, 30, 32.5, and $35{\pm}1^{\circ}C$, Relative Humidity 20~30%). All individuals collected before April 13, 2012 failed to develop into first instar larvae. In contrast, some individuals that were collected on April 11, 2013 successfully developed when reared under $20{\sim}32.5^{\circ}C$ temperature regimes. The developmental duration was shortest at $30^{\circ}C$ (13.3 days) and longest at $15^{\circ}C$ (49.6 days) in the fourth collected colony (April 26 2013). Developmental duration decreased with increasing temperature up to $30^{\circ}C$ and development was retarded at high-temperature regimes ($32.5^{\circ}C$). The lower developmental threshold was $10.1^{\circ}C$ and the thermal constant required to complete egg overwintering was 252DD. The Lactin 2 model provided the best statistical description of the relationship between temperature and the developmental rate of M. pruinosa overwintering eggs ($r^2=0.99$). The distribution of the developmental completion of overwintering eggs was well described by the 2-parameter Weibull function ($r^2=0.92$) based on the standardized development duration. However, the estimated cumulative 50% spring emergence dates of overwintering eggs were best predicted by poikilotherm rate model combined with the 2-parameter Weibull model (average difference of 1.7days between observed and estimated dates).

• Korean Journal of Plant Resources
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• v.27 no.5
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• pp.546-555
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• 2014

The final aim of this study is to develop a biofiltration system integrated with plant vegetation for improving indoor air quality effectively depending on indoor space and characteristics. However, to approach this final goal, several requirements such as constant pressure drops (PDs) and soil moisture contents (SMCs), which influence the capacity design for a proper ventilation rate of biofiltration system, should be satisfied. Thus, this fundamental experiment was carried out to adjust a proper wind speed and to ensure a stabilization of initial SMCs within biofilter for uniform distribution of SMCs and PDs, and for normal plant growth, especially avoiding root stress by wind. Therefore, we designed horizontal biofliter models and manufactured them, and then calculated the ventilation rate, air residence time, and air-liquid ration based on the biofilter depending on three levels of wind speed (1, 2, and $3cm{\cdot}s^{-1}$). The relative humidity (RH) and PD of the humidified air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of lettuce and duffy fern grown within biofilter were measured depending on the three levels of wind speed. As a result of wind speed test, $3{\cdot}sec^{-1}$ was suitable to keep up a proper RH, SMC, and plant growth. Thus, the next experiment was set up to be two levels of initial SMCs (low and high initial SMC, 18.5 and 28.7%) within each biofilter operated and a non-biofiltered control (initial SMC, 29.7%) on the same wind speed ($3cm{\cdot}sec^{-1}$), and measured on the RH and PD of the air coming out through the soil within the biofilter, and SMC of the soil and plant growth parameters of Humata tyermani grown within biofilter. This result was similar to the first results on RHs, SMCs, and PDs keeping up with constant levels, and three SMCs did not show any significant difference on plant growth parameters. However, two biofiltered SMCs enhanced dry weights of the plants slightly than non-biofiltered SMC. Thus, the stability of this biofiler system keeping up major physical factors (SMC and PD) deserved to be adopted for designing an advanced integrated biofilter model in the near future.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.1
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• pp.44-53
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• 2006

This study purposed to investigate air pollution in car shipping yards and, for this purpose, we selected an outdoor open-air yard and an indoor ramp into the ship and measured the concentrations of sulfur dioxide, nitrogen dioxide, carbon monoxide, PM10, PM2.5 and heavy metals in the air. The results of this study are as follows. No significant difference was observed in temperature and humidity between the outdoor and indoor workshop, and the average air flow was 0.52 m/s in the indoor workshop, which is higher than 0.19 m/s in the outdoor workshop(p<0.01). The average concentrations of sulfur dioxide, nitrogen dioxide, carbon monoxide, PM10 and PM2.5 according to workplace were 0.03 ppm(${\pm}0.01$), 0.03 ppm(${\pm}0.01$), 0.46 ppm(${\pm}0.22$), $39.44{\mu}g/m^3$(${\pm}2.45$) and $5.45{\mu}g/m^3$(${\pm}1.15$) respectively in the outdoor workshop, and 0.15 ppm(${\pm}0.05$), 0.22 ppm(${\pm}0.06$), 8.85 ppm(${\pm}3.35$), $236.39{\mu}g/m^3$(${\pm}58.21$) and $152.43{\mu}g/m^3$(${\pm}35.42$) respectively in the indoor workshop. Thus, the concentrations of gaseous substances in the indoor workshop were 4.9-19.2 times higher than those in the outdoor workshop, and the concentrations of fine dusts were 5.9-27.9 times higher(p<0.01). In addition, according to the result of investigating pollutant concentrations according to displacement and the number of car loaded when shipping gasoline cars into the ship, no significant relation between the number of cars loaded and pollutants was observed in shipping passenger cars, but the concentrations of nitrogen dioxide and carbon monoxide got somewhat higher with the increase of the number of cars loaded(p<0.05). In addition, the concentrations of nitrogen dioxide, carbon monoxide, PM10 and PM2.5 in the air were significantly higher when shipping recreational vehicles, the displacement of which is larger than passenger cars, than when shipping passenger cars(p<0.01). On the other hand, the average heavy metal concentrations of the air in indoor workshop were: lead $-0.05{\mu}g/m^3$(${\pm}0.10$); chromium $-0.90{\mu}g/m^3$(${\pm}0.18$); zinc $-0.38{\mu}g/m^3$(${\pm}0.24$); copper $-0.18{\mu}g/m^3$(${\pm}0.22$); and manganese and cadmium not detected. In addition, the complaining rates of 'asthma,' a major symptom of chronic respiratory diseases, were 18.5% and 22.5% respectively in indoor workers and outdoor workers. Thus the rate was somewhat higher in indoor workers but the difference was not statistically significant. The complaining rates of 'chronic cough' and 'chronic phlegm' were very low and little different between indoor and outdoor workers. The results of this study show that the reason for the higher air pollution in indoor than in outdoor workshop is incomplete combustion of fuel due to sudden start and over-speed when cars are driven inside the ship. In order to prevent high air pollution, efficient management measures should be taken including the observance of the optimal speed, the improvement of old ships and the installation of efficient ventilation system.