• Ecology and Resilient Infrastructure
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• v.2 no.3
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• pp.237-246
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• 2015

Heavy metal pollution in soil, such as lead contamination, has become an area of interest in Korea because of urbanization and atmospheric deposition from neighboring countries. Therefore, in this research, eco-physiological responses such as chlorophyll contents, antioxidant enzyme activity, photosynthetic rate, biomass and phytoaccumulation abilities were investigated for 4 commonly used native roadside tree species to suggest suitable tree species to cope with lead contamination. The target species, Ginkgo biloba, Prunus yedoensis, Zelkova serrata and Chionanthus retusus showed lead toxicity by significant changes of chlorophyll contents and antioxidant enzyme activities on treatments over 200 mg Pb/kg. However, biomass and photosynthetic rates only showed significant responses of plants in the highest level (5,000 mg/kg) treatment. Especially, G. biloba did not show any significant changes of antioxidant enzyme activity, photosynthetic rate, and biomass even in the highest level treatment. In low level - environmentally realistic treatments, G. biloba and P. yedoensis showed the highest phytoaccumulation rate of lead from soil. Selecting and planting species like G. biloba which have good phytoaccumulation abilities and resistance to lead contamination by further research will be required to deal with emerging lead contamination.

• Journal of Environmental Science International
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• v.18 no.11
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• pp.1283-1289
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• 2009

Eco-physiological research and the control of Cochlodinium polykrikoides was carried out to elucidate eco-physiological characteristics of red tide organism through culture experiment depending on the condition of photon irradiance. Oxygen consumption of C. polykrikoides was high with a value of 1.12 mg/L/hr in the dark compared with that of 0.13 mg/L/hr at $100{\mu}mEm^{-2}s^{-1}$. DO values in a circular chamber with the lapse of time in seawater containing C. polykrikoides were declined in the dark period. DO values of seawater containing C. polykrikoides in the dark were declined from 7.01 mg/L to 2.65 mg/L in 30 cm depth and from 7.01 mg/L to 6.63 mg/L in 5 cm depth depending on the depth of circular culture vessel. Olive flounder, Paralichthys olivaceus and file fish, Stephanolepis cirrhifer exposed to Cochlodinium showed the separation of the lamella epithelium from gill filament, which disrupted the respiratory process at the gill level.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.120-120
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• 2022

Agrivoltaic System (AVS) was introduced with the concept that it could generate electricity by using the extra light remain after crops use for photosynthesis in farm, which can earn additional income. However, crop yield was declined under the AVS condition due to the decrease in light energy. In the past, many researchers have been studied about crop states under shading conditions. However, the phenomenon of partial shading such as under the AVS is not well studied. In this study, to figure out the response of crop under the different light conditions, the electron transport rate (ETR) and non-photochemical quenching (NPQ) of rice was investigated using the chlorophyll fluorescence measurement. Also, physiological changes of crops under the shading conditions were investigated. The growth experiment under partial shading under AVS and overall shading which made of 35% shade cloth was conducted to understand the eco-physiological responses of rice to light in terms of the photosynthesis. Under the shading conditions, SPAD value and chlorophyll contents were higher, but the leaf thickness was lower than control. The overall shading condition show lower ETR than others during the growing season. In contrast, NPQ was higher than other treatments. This means the available light energy cannot contribute to photosynthesis under the shading condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.5
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• pp.548-555
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• 1995

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by sowing method. Yield and yield contribution rates of tillers were investigated with the data of field experiments in the Honam Crops Experiment Station of Iri, Korea from October 1986 to July 1987. Narrow-seeding (each row placement 40cm$\times$seeding width of each row 18cm), drill-seeding (20cm$\times$5cm) and broadcasting on wide ridge (each ridge placement 120cm$\times$ridge width 90cm) were applied to examine the effects of various sowing methods. Primary tillers such as mainstem, 1 and 2 produced ears in all treatments, but the ear from a secondary tiller of 11 was observed only in broadcasting on wide ridge. Drill-seeding was the highest in number of spikelet, grain and plump grain per ear, while narrow-seeding being the lowest. The plump grain yield per square meter was 679.8g in narrow-seeding, while drill-seeding and broadcasting produced more than narrow seeding by 28.7% and 16.8% respectively. The actual yields per l0a for sowing methods showed a similar pattern to plump grain yield per square meter in which the yield was 567.6kg by narrow-seeding and the increments of drill-seeding and broadcasting were 30.6% and 15.4%, respectively.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.3
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• pp.163-168
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• 2021

The growth experiment under shading condition has been performed to understand the eco-physiological responses of crops to light in terms of photosynthesis. There are two types of shading: overall shading and partial shading. In this study, the chlorophyll fluorescence of soybean was observed under the overall shading of the box made by polyresin and the partial shading at agrivoltaic system. The overall shading condition during vegetative growth induced lower SPAD and Electron transport rate (ETR). These lower values recovered after removal of shading box. However, the Non-photochemical fluorescence quenching (NPQ) became lower under overall shading and higher under partial shading. Such increase in NPQ limited crop photosynthesis even though the ETR was almost same to the control without shading treatment. Under the condition of partial shading, the values of SP AD and ETR for soybean did not change. However, the NPQ was higher than control condition. This suggests that the crop photosynthesis under both types of shading would be decreased by different eco-physiological processes which are the lower ETR in overall shading and the higher NP Q in partial shading despite the reduced light under shading conditions.

• Journal of Wetlands Research
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• v.7 no.4
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• pp.33-42
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• 2005

Wetlands often function as a nutrient sink. It is well known that increased input of nutrient increases the primary productivity but it is not well understood what is the fate of produced biomass in wetland ecosystem. Water and sediment quality, decomposition rate of cellulose, and sediment accumulation rate in 11 montane marshes in northern Sierra Nevada, California were analyzed to trace the effect of nitrogen and phosphorus content in water on nutrient dynamics. Concentrations of ammonium, nitrate, soluble reactive phosphorus (SRP) in water were in the range of 27 to 607, 8 to 73, and 6 to 109 ppb, respectively. Concentrations of ammonium, calcium, magnesium, sodium, and potassium in water were the highest in Markleeville, which has been impacted by animal farming. Nitrate and SRP concentrations in water were the highest in Snow Creek, which has been impacted by human residence and a golf course. Cellulose decomposition rates ranged from 4 to 75 % per 90 days and the highest values were measured in Snow Creek. Concentrations of total carbon, nitrogen, and phosphorus in sediment ranged from 8.0 to 42.8, 0.5 to 3.0, and 0.076 to 0.162 %, respectively. Accumulation rates of carbon, nitrogen, and phosphorus fluctuated between 32.7 to 97.1, 2.4 to 9.0, and 0.08 to $1.14gm^{-2}yr{-1}$, respectively. Accumulation rates of carbon and nitrogen were highest in Markleeville and that of phosphorus was highest in Lake Van Norden. Correlation analysis showed that decay rate is correlated with ammonium, nitrate, and SRP in water. There was no correlation between element content in sediment and water quality. Nitrogen accumulation rate was correlated with ammonium in water. These results showed that element accumulation rates in montane wetland ecosystems are determined by decomposition rate rather than nutrient input. This study stresses a need for eco-physiological researches on the response of microbial community to increased nutrient input and environmental change because the microbial community is responsible for the decomposition process.

• Journal of the Ergonomics Society of Korea
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• v.30 no.1
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• pp.237-250
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• 2011

The train transportation has a lot of advantages-energy efficiency is high, it is eco-friendly, safety is better than normal roads and it is possible for people to arrive on time. In these days, the valuation of ride comfort, which is only limited to road transportation, is newly recognized in order to having competitiveness from other transportation. Especially, in the development of the Korean high-speed railroad business, the ride comfort enhancement of train is very important problem to be solved. Currently, there are international standards of ride comfort such as UIC13, ISO2631. In Korea case, although it has own standard like KS R9216, it mainly depends on the physical parameter such as vibration and noise. So recently, in the valuation of ride comfort, the movements of living parameter technique introduction are increasing on the base of Japan and many developed countries of Europe techniques. Presently, the method of train ride comfort is mainly based of vibration, that is, mechanical parameter adding selection of variable acceleration and noise. This paper would like to show biological parameter; heart rate and blood pressure variation. This method is more direct, based on human body response, than mechanical parameter method. In this experiment, the variability of heart rate and blood pressure of passengers according to tilting angle change of Train, the Korean tilting train, we are supposed to know that the extent of tilting on the simulation has influence on variability of heart rate and blood pressure, which are living parameter of heart's blood.

• Mycobiology
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• v.45 no.4
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• pp.240-254
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• 2017

Cereal grains are the most important food source for humans. As the global population continues to grow exponentially, the need for the enhanced yield and minimal loss of agricultural crops, mainly cereal grains, is increasing. In general, harvested grains are stored for specific time periods to guarantee their continuous supply throughout the year. During storage, economic losses due to reduction in quality and quantity of grains can become very significant. Grain loss is usually the result of its deterioration due to fungal contamination that can occur from preharvest to postharvest stages. The deleterious fungi can be classified based on predominance at different stages of crop growth and harvest that are affected by environmental factors such as water activity ($a_w$) and eco-physiological requirements. These fungi include species such as those belonging to the genera Aspergillus and Penicillium that can produce mycotoxins harmful to animals and humans. The grain type and condition, environment, and biological factors can also influence the occurrence and predominance of mycotoxigenic fungi in stored grains. The main environmental factors influencing grain fungi and mycotoxins are temperature and $a_w$. This review discusses the effects of temperature and $a_w$ on fungal growth and mycotoxin production in stored grains. The focus is on the occurrence and optimum and minimum growth requirements for grain fungi and mycotoxin production. The environmental influence on aflatoxin production and hypothesized mechanisms of its molecular suppression in response to environmental changes are also discussed. In addition, the use of controlled or modified atmosphere as an environmentally safe alternative to harmful agricultural chemicals is discussed and recommended future research issues are highlighted.

• ALGAE
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• v.34 no.3
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• pp.217-228
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• 2019

The marine brown algal genus Colpomenia has a worldwide distribution, with five species reported in Korea and Japan. However, no studies to date attempted to identify the number of species and geographical distribution of Colpomenia along Chinese coast. To fill the biodiversity knowledge gap, we analyzed 63 mitochondrial cox3 and 62 mitochondrial atp6 sequences of Colpomenia specimens collected from 30 localities along the Chinese coast. Maximum likelihood and Bayesian inference trees suggest the presence of at least three Colpomenia species (i.e., C. peregrina, C. claytoniae, and C. sinuosa) in China. C. peregrina and C. claytoniae are documented for the first time. C. sinuosa was only found in the South China Sea and its distribution didn't overlap with that of C. peregrina which was found in the Yellow-Bohai Sea and the East China Sea. C. claytoniae appears to be confined to three isolated islands in the East and the South China Sea, where it occurs in sympatry with, respectively, C. peregrina and C. sinuosa. Future study can focus on comparing eco-physiological differences of Colpomenia species in response to environmental variables and exploring possible genetic hybridization / introgression at inter-specific contact zones.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.671-683
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• 1995

This study was aimed to provide understanding on the eco-physiological response of barley tillers as affected by sowing depth. Yield and yield contribution rate of tillers were investigated with the data of field experiments in the former Wheat and Barley Research Institute of Suwon, Korea from October 1983 to July 1984. When barley was sowed in various depth of 1, 3, 5, 7 and 9cm below the ground surface, 13 mainstem leaves appeared by 3 and 5cm treatments, and 11 leaves by 1, 7 and 9cm treatments. The effective tillers were observed from 8/0 in lcm depth, while 10/0 in 3-5cm depth and 9/0 in 7cm depth. There was no coleoptile tiller in 7cm depth sowing. Deep and shallow sowings produced fewer leaves and tillers, as early growth was hindered by deep sowing whereas cold damage was apparent in shallow sowing. Accordingly, more effective tillers per plant and higher grain weight per ear were observed in 3∼5cm depth sowing. Yield contribution by the tillers with various sowing depth was as follows: mainstem, 1, 2, 11, 3, 21, 4 and 12. The contribution of 1P, 13, 2P, 23 and 31 varied with the treatments.