• Asian-Australasian Journal of Animal Sciences
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• v.24 no.4
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• pp.509-516
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• 2011

The performance of naked neck and normal chicken was evaluated with respect to growth, carcass, immune, biochemical and stress parameters under winter and summer seasons to assess the suitability of naked neck birds under high temperatures in the global scenario of climate change. The growth performance was significantly ($p{\leq}0.05$) higher in naked neck chicken in the summer season. The dressing percentage was significantly ($p{\leq}0.05$) higher in naked neck birds in both winter and summer season because of reduced plumage. The thigh, giblet and feather proportion significantly ($p{\leq}0.05$) varied between naked neck and normal chickens in summer season. The humeral immune response to sheep red blood cells (SRBC), Newcastle disease vaccine (NDV) and cutaneous basophil hypersensitivity (CBH) did not show any significant differences among the chicken groups. The protein and cholesterol concentration observed was within the normal ranges. The total cholesterol levels in plasma were significantly ($p{\leq}0.05$) lower in naked neck birds in both the seasons. H:L ratio was significantly ($p{\leq}0.05$) lower in summer season indicating less stress in naked neck chicken. Basophil and eosinophil concentration was significantly ($p{\leq}0.05$) higher in normal chicken in summer. The lipid peroxidation was higher in full feathered birds under summer stress. The enzyme glutathione reductase (GR) levels were significantly higher during the summer and varied significantly ($p{\leq}0.05$) between the normal and naked neck chicken in both seasons. The results indicated that the naked neck birds performed significantly better at high ambient temperatures with respect to growth, carcass and biochemical parameters. It was concluded that the ability of the naked neck chicken to adapt to high temperatures foresees a viable option for the biological mitigation of climate change.

• Journal of Ecology and Environment
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• v.38 no.1
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• pp.1-14
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• 2015

Whilst it is clear that increasing temperatures from global environmental change will impact the positions of alpine treelines, it is likely that a range of regional and local scaled factors will mediate the overall impact of global scale climate drivers. We summarized 12 categories of abiotic and biotic factors as 4 groups determining treeline positions. First, there are global factors related to climate-induced growth limitation and carbon limitation. Second, there are seven regional and local factors related to treeline dynamics including frost stress, topography, water stress, snow, wind, fire and non-fire disturbance. Third, species-specific factors can control treeline dynamics through their influence on reproduction and life history traits. Fourth, there are positive feedbacks in structuring the dynamics of treelines. Globally, the commonly accepted growth limitation hypothesis is that growth at a treeline is limited by temperature. Meanwhile, positive feedbacks between canopy cover and tree establishment are likely to control the spatial pattern and temporal dynamics of many treelines. The presence of non-linear dynamics at treelines has implications for the use of treelines as barometers of climate change because the lagged responses and abrupt shifts inherent in non-equilibrium systems may combine to mask the overall climate trend.

• Journal of Environmental Science International
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• v.32 no.11
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• pp.811-820
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• 2023

This study investigated the protective effects of shade nets on Abies koreana seedlings subjected to high temperature and luminosity stress, which are pertinent for plant survival in climate change scenarios. This study, conducted at Konkuk University, compared the growth, survival, and soil conditions of 3-year-old specimens across natural, greenhouse, and shaded settingsfrom July to September 2022. Our findings demonstrated that shade nets significantly enhanced seedling survival by moderating soil temperature and moisture. This is particularly evident in high-temperature conditions, where shade nets mitigate stress on seedlings and safeguard them from excessive sunlight exposure. Proper net installation height and location are crucial for optimal temperature and humidity control, suggesting broader applicability for various species and offering strategies to combat the ecological impacts of climate change.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.3
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• pp.170-174
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• 2018

Environmental stresses caused by climate change, such as high temperature, drought and salinity severely impact plant growth and productivity. Among these factors, high temperature stress will become more severe during summer. In this study, we examined physiological and molecular responses of maize plants to high temperature stress during summer. Highest level of $H_2O_2$ was observed in maize leaves collected July 26 compared with June 25 and July 12. Results indicated that high temperature stress triggers production of reactive oxygen species (ROS) in maize leaves. In addition, photosynthetic efficiency (Fv/Fm) sharply decreased in leaves with increasing air temperatures during the day in the field. RT-PCR analysis of maize plants exposed to high temperatures of during the day in field revealed increased accumulation of mitochondrial and chloroplastic small heat shock protein (HSP) transcripts. Results demonstrate that Fv/Fm values and organelle-localized small HSP gene could be used as physiological and molecular indicators of plants impacted by environmental stresses.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.115-125
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• 2020

Background: The phenomenon of tree dieback in forest ecosystems around the world, which is known to be associated with high temperatures that occur simultaneously with drought, has received much attention. Korea is experiencing a rapid rise in temperature relative to other regions. Particularly in the growth of evergreen conifers, temperature increases in winter and spring can have great influence. In recent years, there have been reports of group dieback of Pinus densiflora trees in Korea, and many studies are being conducted to identify the causes. However, research on techniques to diagnose and monitor drought stress in forest ecosystems on local and regional scales has been lacking. Results: In this study, we developed and evaluated an index to identify drought and high-temperature vulnerability in Pinus densiflora forests. We found the Drought Stress Index (DSI) that we developed to be effective in generally assessing the drought-reactive physiology of trees. During 2001-2016, in Korea, we refined the index and produced DSI data from a 1 × 1-km unit grid spanning the entire country. We found that the DSI data correlated with the event data of Pinus densiflora mass dieback compiled in this study. The average DSI value at times of occurrence of Pinus densiflora group dieback was 0.6, which was notably higher than during times of nonoccurrence. Conclusions: Our combination of the Standard Precipitation Index and growing degree days evolved and short- and long-term effects into a new index by which we found meaningful results using dieback event data. Topographical and biological factors and climate data should be considered to improve the DSI. This study serves as the first step in developing an even more robust index to monitor the vulnerability of forest ecosystems in Korea.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.446-454
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• 2023

The impact of climate change on agriculture is substantial, especially as global warming is projected to lead to varying temperature and humidity patterns in the future. These changes pose a higher risk for both crops and livestock, exposing them to environmental stressors under altered climatic conditions. Specifically, as temperatures are expected to rise, the risk of heat stress is assessable through the Temperature-Humidity Index (THI), derived from temperature and relative humidity data. This study involved the comparison of THI collected from 10 Korea Meteorological Administration ASOS stations spanning a 60-year period from 1961 to 2020. Moreover, high-resolution temperature and humidity distribution data from 1981 to 2020 were employed to generate high-resolution TH I distributions, analyzing temporal changes. Additionally, the number of days characterized by heat stress, derived from TH I, was compared over different time periods. Generally, TH I showed an upward trend over the past, albeit with varying rates across different locations. As TH I increased, the frequency of heat stress days also rose, indicating potential future cost increases in the livestock industry due to heat-related challenges. The findings emphasize the feasibility of evaluating heat stress risk in livestock using THI and underscore the need for research analyzing THI under future climate change scenarios.

• The Korean Journal of Health Service Management
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• v.10 no.3
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• pp.27-37
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• 2016

Objectives : This study was conducted to test the influence of job stress and calling on the organizational commitment of clinical nurses. Methods : 220 clinical nurses at two university hospitals in Busan were recruited. They were asked to complete a questionnaire, and 192 data sets were included in the statistical analysis. Results : The mean score of the clinical nurses' organizational commitment was 4.0. All subdomains of job stress and calling were found to have correlations with organizational commitment. The organizational system (t=-6.099, p<.001), lack of reward (t=-3.990, p<.001), purpose/meaningfulness (t=3.624, p<.001), and occupational climate (t=-3.581, p<.001) were revealed to have influences on the organizational commitment. The model was statistically significant, explaining 52.2% of the variance (F=47.808, p<.001). Conclusions : To help clinical nurses become committed to their organizations, administrators need to build fair and rational organizational systems, strengthen various types of rewards, and help nurses reconcile nursing and the meaning of their lives. In addition, every nurse should endeavor to change the nursing organizational climate which is based on vertical collectivism, to a rational climate.

• Journal of Environmental Science International
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• v.27 no.12
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• pp.1261-1269
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• 2018

The purpose of this study was to investigate changes in the external thermal environment, following the application of evaporative cooling systems in buildings, in response to climate change. In order to verify changes in the external thermal environment, a T-test was performed on the microclimate, Thermal Comfort Index (TCI), and building surface temperature. Differences in microclimate, following the application of the evaporative cooling system in the building, were significant in terms of temperature and relative humidity. In particular, temperature decreased by more than 7% when the evaporative cooling system was applied. According to the results of the Thermal Comfort Index analysis, the Wet-Bulb Globe Temperature (WBGT) was below the limit of outdoor activities, indicating that outdoor activities were possible. The Universal Thermal Climate Index (UTCI) values were within the very strong heat stress range when the evaporative cooling system was not applied, When the system was applied, the UTCI values were within the strong heat stress range, indicating that they were lowered by one level. The building surface temperature decreased by ~10% or more when the evaporative cooling system was applied, compared to when it was not applied. Finally, the outside surface temperature of the building decreased by ~12% or more when the system was applied, compared to when it was not applied. We conclude that the energy saving effect of the building was significant.

• Journal of Korea Water Resources Association
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• v.57 no.3
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• pp.225-236
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• 2024

To prepare for the impending climate crisis, it is necessary to establish policies and strategies based on scientific predictions and analyses of climate change impacts. For this, climate change should be considered, however, in conventional scenario-led approach, researchers select and utilize representative climate change scenarios. Using the representative climate change scenarios makes prediction results high uncertain and low reliable, which leads to have limitations in applying them to relevant policies and design standards. Therefore, it is necessary to utilize scenario-neutral approach considering possible change ranges due to climate change. In this study, hydrologic risk was estimated for Boryeong after generating 343 time series of climate stress and calculating drought return period from bivariate drought frequency analysis. Considering 18 scenarios of SSP1-2.6 and 18 scenarios of SSP5-8.5, the results indicated that the hydrologic risks of drought occurrence with maximum return period ranged 0.15±0.025 within 20 years and 0.3125±0.0625 within 50 years, respectively. Therefore, it is necessary to establish drought policies and countermeasures in consideration of the corresponding hydrologic risks in Boryeong.

• Research in Plant Disease
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• v.25 no.2
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• pp.62-70
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• 2019

The global warming by increased $CO_2$ will effect of plant pathogenic microorganisms and resistance of host plants, and it is expected to affect host-pathogen interactions. This study used Capsicum annuum L. and Xanthomonas euvesicatoria, a pathogenic bacteria of pepper, to investigate interactions between hosts and pathogens in a complex environment with increasedcultivation temperature and drought stress. As a result, the bacterial spot disease of C. annuum L. caused by X. euvesicatoria was $35^{\circ}C$ higher than $25^{\circ}C$. In addition, the effect on water potential on bacterial spot disease was much greater water potential -150 kPa than -30 kPa. The disease progress and severity higher than water potential -30 kPa. This result will useful for understanding interaction with red pepper and X. euvesicatoria under the complex environment with increased cultivation temperature and in water potential -150 kPa drought stress in the future.