• The Plant Pathology Journal
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• 제32권3호
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• pp.260-265
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• 2016

We observed the changes in aggressiveness and fecundity of the anthracnose pathogen Colletotrichum acutatum on hot pepper, under the ambient and the twice-ambient treatments. Artificial infection was repeated over 100 cycles for ambient ($25^{\circ}C/400ppm$ $CO_2$) and twice-ambient ($30^{\circ}C/700ppm$ $CO_2$) growth chamber conditions, over 3 years. During repeated infection cycles (ICs) on green-pepper fruits, the aggressiveness (incidence [% of diseased fruits among 20 inoculated fruits] and severity [lesion length in mm] of infection) and fecundity (the average number of spores per five lesions) of the pathogen were measured in each cycle and compared between the ambient and twice-ambient treatments, and also between the early (ICs 31-50) and late (ICs 81-100) generations. In summary, the pathogen's aggressiveness and fecundity were significantly lower in the late generation. It is likely that aggressiveness and fecundity of C. acutatum may be reduced as global $CO_2$ and temperatures increase.

• Journal of Ecology and Environment
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• 제37권2호
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• pp.61-67
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• 2014

Mankyua chejuense is a native endangered plant distributed only in Gotzawal, a forested wetland, in Jeju Province, Korea. In order to determine the optimal environmental conditions for the growth and development of M. chejuense, we investigated the above- and below-ground growth responses and survival rate to various soil texture (sand and clay), water regimes (flooding and non-flooding), and $CO_2+T$ (ambient and elevated) conditions. All of the treatments had significant effects on aboveground growth parameters, while only the water regime and $CO_2+T$ treatments influenced belowground growth. The survival rate of M. chejuense was about twice higher under the sand, non-flooding and elevated $CO_2+T$ conditions than clay, flooding and ambient $CO_2+T$ conditions. These results indicate that M. chejuense grows in well-drained sandy soil conditions and elevated $CO_2$ concentration and temperature situations. Thus, there is a need to maintain M. chejuense under constant non-flooding soil conditions by implementing appropriate soil drainage strategies.

• Environmental Engineering Research
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• 제22권4호
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• pp.347-355
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• 2017

This study investigated how the combined changes in environmental conditions and nitrogen (N) deposition influence the mineralization processes and carbon (C) dynamics of wetland soil. For this objective, we conducted a growth chamber experiment to examine the effects of combined changes in environmental conditions and N deposition on the anaerobic decomposition of organic carbon and the emission of greenhouse gases from wetland soil. A chamber with elevated $CO_2$ and temperature showed almost twice the reduction of total decomposition rate compared to the chamber with ambient atmospheric conditions. In addition, $CO_2$ fluxes decreased during the incubation under the conditions of ambient $CO_2$ and temperature. The decrease in anaerobic microbial metabolism resulted from the presence of vegetation, which influences the litter quality of soils. This can be supported by the increase in C/N ratio over the experimental duration. Principle component analysis results demonstrated the opposite locations of loadings for the cases at the initial time and after three months of incubation, which indicates a reduction in the decomposition rate and an increasing C/N ratio during the incubation. From the distribution between the decomposition rate and gas fluxes, we concluded that anaerobic decomposition rates do not have a significantly positive relationship with the fluxes of greenhouse gas emissions from the soil.

• 한국환경생태학회지
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• 제31권6호
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• pp.557-563
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• 2017

천마(Gastrodia elata Blume)는 난초과 다년생 기생식물로 곰팡이균과 공생하는 독특한 생활방식을 가진다. 천마의 지하근은 고혈압, 뇌졸중, 백혈병, 두통 특히 신경쇠약치료 등에 쓰이는 약용식물이다. 본 연구는 지구온난화가 천마의 생태적 반응에 미치는 영향을 알아보기 위해 보통의 야외 대기환경과 같은 대조구, 대조구보다 온도를 약 $2^{\circ}C$ 상승시킨 온도상승구, 온도와 함께 대조구보다 $CO_2$ 농도를 약 2배 증가시킨 $CO_2$+온도상승구에서 참나무 원목, 뽕나무버섯균, 종마를 함께 파종하고, 재배하여 생식기관과 지하근의 생물량을 비교 관찰하였다. 그 결과, 꽃대 수는 온도상승구> 대조구> $CO_2$+온도상승구 순으로 적었다. 꽃대 길이는 온도상승구> 대조구> $CO_2$+온도상승구 순으로 짧았다. 화서 길이는 대조구> 온도상승구> $CO_2$+온도상승구 순으로 짧았다. 생식기관의 무게는 온도상승구> 대조구> $CO_2$+온도상승구 순으로 가벼웠다. 지상부의 생물량은 온도상승구> 대조구> $CO_2$+온도상승구 순으로 낮았다. 생산된 근경의 수는 온도상승구> 대조구> $CO_2$+온도상승구 순으로 적었다. 근경의 생물량은 온도상승구> 대조구> $CO_2$+온도상승구 순으로 낮았다. 이러한 결과는 온도만 올라간 환경조건에서는 천마의 생육은 활발하여 생산량이 증가하지만, 지구온난화조건인 온도와 $CO_2$ 농도가 동시에 상승하는 조건에서는 천마의 생육이 불량하게 됨을 의미하는 것이다. 따라서, 천마의 성마와 종마 생산량을 높이기 위해서는 재배지의 적정지온 $20{\sim}25^{\circ}C$를 유지하고, 높은 $CO_2$ 농도에 노출되지 않도록 하여야 할 것이다.

• 한국입자에어로졸학회지
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• 제16권2호
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• pp.49-59
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• 2020

Various devices have been developed to the measurement of particulate matter pollutants, and Optical Particle Counter (OPC) that can be easily and quickly measured is widely used lately. The measured value by OPC is converted to weight concentration using the correction factor (CF). The calculation of CF is very important to improve the reliability and accuracy of OPC. In this study, the CF calculation study of light scattering laser photometer (model 8533, TSI) was carried out to measure in the atmospheric environment using 2 gravimetric devices and 3 light scattering laser photometer devices. Regression analysis and Tukey tests were used to significance the test of measurement devices. Measurements were carried out twice. There was a comparative analysis of measurement data between light scattering laser photometer and gravimetric devices in 1st measurement, and then the Evaluation of PM2.5 concentration corrected by CF performed in 2nd measurement. As a result of the significance analysis between light scattering laser photometer and gravimetric devices, the correlation between the same method was high, but the correlation between different methods was low. CF was calculated as 0.4258 based on the measurement results, and it is a similar level to previous studies at home and abroad. It is expected that these results can be used as basic data in the future study for air quality measurement research using light scattering laser photometer. Also, in order to improve the accuracy of the measurement techniques and the development of technology in the atmospheric environment, CF calculation research should be conducted continuously.

• Tuberculosis and Respiratory Diseases
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• 제55권6호
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• pp.570-578
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• 2003

배 경 : 황사는 주로 $10{\mu}m$이하의 미세먼지($PM_{10}$)로서 $PM_{10}$의 증가는 황사현상의 증가와 매우 밀접한 관련이 있다. $PM_{10}$은 그 크기로 보아 호흡기에 침착이 가능하고 따라서 호흡기 증상 및 폐기능에 영향을 미칠 수 있올 것으로 생각되나 아직 이에 대한 연구는 없었다. 이에 연구자들은 천식으로 확진된 환자를 대상으로 황사 기간 중에 $PM_{10}$을 포함한 대기오염물질이 호흡기증상 및 폐기능에 미치는 영향을 알아 보고자 하였다. 대상 및 방법 : 인천지역 거주자이고 천식으로 확진된 환자를 대상으로 2002년 3월 2일부터 6월 14일까지 매일 최소 2회 이상의 최대호기유속 측정, 속효성 기관지 확장제 사용회수, 야간 증상, 증상 점수, 설외활동량 등을 기록하였다. 또한 대기오염지수인 $PM_{10}$, $SO_2$, $NO_2$, $O_3$, 황사발생일, 기온 및 습도를 측정하여 이들과 최대호기유속 및 변동률, 증상과의 관련성, 야간 증상 및 속효성 기관지확장제 사용회수 등의 연관성을 분석하였다. 결 과 : 대상환자는 남자 31 명, 여자 33명으로 평균 연령은 $46.1{\pm}14.1$세, FEV1은 $2.2{\pm}0.9L$, FEV1%는 $71.5{\pm}24.9%$ 이었다. 연구 기간 중 황사 발생일은 총 14일이었으며, $PM_{10}$수치는 황사발생일에 $188.5{\pm}163.0{\mu}g/m^3$, 비황사발생일에 $60.1{\pm}19.9{\mu}g/m^3$로 황사 발생기간 동안에 높게 측정되었다(p<005). 일일 평균 $PM_{10}$이 높은 날에는 대상 환자의 오전 및 오후 최대 호기유속이 낮아지는 경향을 보였으며(p<0.05), 최대 호기유속 변화율이 증가하였고(p<0.05), 야간에 천식으로 인해 잠을 깨는 횟수가 증가하였다(p<0.05). 반면, 황사 기간 중에 $SO_2$, $NO_2$, $O_3$ 등 다른 대기오염지수와 증상 및 최대호기유속의 변화는 상관성이 없었다(p>0.05). CO는 황사와 관계없이 천식환자에서 최대 호기유속 변동률 및 평균 최대호기유속에 영향을 미치고 있었다(p<0.05). 결 론 : 황사 기간 중 증가하는 미세먼지 농도는 기관지 천식 환자의 호흡기 증상의 악화 및 폐기능의 저하를 초래할 수 있다.

• Journal of Preventive Medicine and Public Health
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• 제32권4호
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• pp.473-481
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• 1999

Objectives: In recent days, the problem of odor pollution in community near Sihwa Industrial complex, Kynuggi Province is becoming of significant public concern. We have investigated the health effects of the Sihwa residents from odor pollution comparing with other less polluted areas. Methods: The Ansan and Kuri Cities were selected as control areas. The parents of the elementary and middle school students in these three areas were surveyed with structured questionnaire twice, Nov 1997 and Jure 1998 each. As a exposure index, the ambient air concentrations of five major air pollutants(particulates, $O_3,\;SO_2,\;NO_2$, CO) and subjective odor perception were used. We have focused health outcomes such as the prevalence of nonspecific irritant symptoms, respiratory disease among family members and the score of qualify of life(QOL). Results: Although the mean concentrations of major air pollutants except particulates were similar or lower in Sihwa than other areas, the odor perception rate and the monthly odor perception days were significantly higher. It suggested that odor producing chemical compounds are the major source of environmental pollution problem. There were higher prevalence rates of nonspecific irritant symptoms and respiratory disease among family members in Sihwa than other control areas. The QOL score was also lower in Sihwa. The odor perception proved to be a most important factor in reporting adverse health effects and lowering the QOL score. Conclusion: The residents living near Sihwa industrial complex were suffering from more adverse health symptoms and poorer QOL status than control areas. And it may be due to environmental odor pollution from industrial complex. Therefore, further research will be needed for monitoring of the responsible chemicals emitted from industries.