• Journal of Life Science
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• v.30 no.2
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• pp.156-161
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• 2020

Since industrialization, the production and utilization of various chemicals has contributed to improving the quality of our lives, but the subsequent discharge of massive waste is inevitable, and environmental pollution is becoming more serious every day. Exposure to chemicals as a result of environmental pollution is having a negative effect on human health and the ecosystem, and cleaning up the polluted environment that can affect our lives is a very important issue. Toxic aromatic compounds have been detected frequently in soil, groundwater, and wastewater because of the extensive use of oil products, and phenol, which is used to produce synthetic resins, textiles, and dyes, is one of the major pollutants, along with insecticides and preservatives. Phenol can cause dyspnea, headache, vomiting, mutation, and carcinogenesis. Phenol-degrading bacterium DWB-1-8 was isolated from the activated sludge of textile wastewater; this strain was identified as Comamonas testosteroni by 16S rRNA gene sequencing. The optimal culture conditions for the cell growth and degradation of phenol were 0.7% K₂HPO₄, 0.6% NaH₂PO₄, 0.1% NH₄NO₃, 0.015% MgSO₄·7H₂O, 0.001% FeSO₄·7H₂O, an initial pH of 7, and a temperature of 30℃. The strain was also able to grow by using other toxic compounds, such as benzene, toluene, or xylene (BTX), as the sole source of carbon.

• Korean Journal of Ecology and Environment
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• v.48 no.4
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• pp.219-228
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• 2015

To secure water resources, dams are normally constructed on the upper - middle part of streams, and it generates physical disturbances such as habitat alteration and stream fragmentation. Such construction can restrict movement of aquatic organisms, especially for freshwater fish which is one of top predator in aquatic ecosystem, and cause genetic fragmentation and community change. In this study, to investigate impact of habitat alteration after dam construction on freshwater fish, we monitored fish community changes, and compared fish fauna between dam reservoir and inflows. Additionally, movement characteristics and habitat boundaries of four species were identified by radio telemetry method. The study was conducted in the Gunwi Dam which was constructed in December 2010. Radio telemetry was applied to Pungtungia herzi, Zacco platypus (living lotic and lentic), Silurus asotus (lentic preferred species) and Zacco koreanus (lotic preferred species). The number of species was remarkably decreased (4 family, 10 species) comparing with before the dam construction (7 family, 15 species). Specifically, Coreoleuciscus splendidus, Niwaella multifasciata, Liobagrus mediadiposalis, Coreoperca herzi and Odontobutis platycephala that inhabit in the lotic environment were not collected in the study area. A total of 8 species were caught in both the dam reservoir and tributaries except 2 species (C. auratus and S. asotus). Sorenson's similarity between the reservoir and its tributaries was high (0.842). All of the radio tagged species stayed in the reservoir except S. asotus which moved to the tributary. These species mainly utilized the shallow littoral zone as a habitat. These results could be useful as a baseline data for efficient management of fishes in lakes.

• Korean Journal of Ecology and Environment
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• v.48 no.4
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• pp.229-237
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• 2015

This study aims to offer basic data to effectively preserve and manage pine forests using more precise pine forests' distribution status. In this regard, this study predicts the geographical distribution change of pine forests growing in South Korea, due to climate change, and evaluates the spatial distribution characteristics of pine forests by age. To this end, this study predicts the potential distribution change of pine forests by applying the MaxEnt model useful for species distribution change to the present and future climate change scenarios, and analyzes the effects of bioclimatic variables on the distribution area and change by age. Concerning the potential distribution regions of pine forests, the pine forests, aged 10 to 30 years in South Korea, relatively decreased more. As the area of the region suitable for pine forest by age was bigger, the decreased regions tend to become bigger, and the expanded regions tend to become smaller. Such phenomena is conjectured to be derived from changing of the interaction of pine forests by age from mutual promotional relations to competitive relations in the similar climate environment, while the regions suitable for pine forests' growth are mostly overlap regions. This study has found that precipitation affects more on the distribution of pine forests, compared to temperature change, and that pine trees' geographical distribution change is more affected by climate's extremities including precipitation of driest season and temperature of the coldest season than average climate characteristics. Especially, the effects of precipitation during the driest season on the distribution change of pine forests are irrelevant of pine forest's age class. Such results are expected to result in a reduction of the pine forest as the regions with the increase of moisture deficiency, where climate environment influencing growth and physiological responses related with drought is shaped, gradually increase according to future temperature rise. The findings in this study can be applied as a useful method for the prediction of geographical change according to climate change by using various biological resources information already accumulated. In addition, those findings are expected to be utilized as basic data for the establishment of climate change adaptation policies related to forest vegetation preservation in the natural ecosystem field.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.6
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• pp.328-333
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• 2005

Ammonia volatilization is the major form of nitrogen (N) loss from flooded paddy soils and causes low N use efficiency. The effects of controlled release fertilizer (latex coated urea complex fertilizer, LCU) on reducing N loss by ammonia volatilization was measured comparing with urea in rice culture system of direct seeding on dry soil. In the treatment of urea, $NH_4-N$ concentration in surface water after flooding increased rapidly up to $8-10mg\;L^{-1}$ as affected by topdressing, while in the LCU treatment $NH_4-N$ concentration in surface water was less than $1mg\;L^{-1}$ during rice growing season. Relation of $NH_4-N$ concentration in surface water and ammonia volatilization was significant in urea treatment. The amount of ammonia volatilized from rice paddy of LCU treatment was $2.4-3.0kg\;ha^{-1}$ and the rate of ammonia volatilization from N fertilizer applied was only 2.0-2.3% compared with 5.9-7.9% in urea treatment. Therefore, N loss by ammonia volatilization could be reduced by 72-76% with by LCU compared with urea in rice culture system of direct seeding on dry soil.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.6
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• pp.321-327
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• 2005

Ammonia ($NH_3$) volatilization was measured from latex coated urea (LCU) and normal urea treated rice paddy under transplanting rice culture in Milyang in 2002 and 2003. The $NH_3$ volatilization from incubation experiment was significantly related with ammonium-N ($NH_4-N$) concentration and pH in the surface water. The correlation coefficients of $NH_3$ volatilization compared to the $NH_4-N$ and pH in surface water were significantly higher in urea than LCU. The $NH_3$ volatilization from both urea and LCU treatments was not increased in surface water of pH less than 8.0, while $NH_3$ volatilization increased significantly in the surface water of pH over 8.0. The results in the field experiment indicated that $NH_3$ volatilization after top-dressing of urea increased rapidly with increasing $NH_4-N$ concentration in soil and floodwater, and highest from 7 to 10 days after top-dressing. The amount of $NH_3$ volatilized from urea treatment was in the range of $4.9-8.4kg\;N\;ha^{-1}$. The variations of $NH_3$ volatilization in 2002 and 2003 were caused by changed N dynamics due to the different weather conditions such as rainfall and temperature. The amount of $NH_3$ volatilized from LCU treatment was significantly reduced compared to that of urea. The reason for the reduced $NH_3$ volatilization in LCU treatment would be due to the lower concentration of $NH_4-N$ in floodwater. The amount of $NH_3$ volatilized from LCU treated rice paddy was in the range of $1.2-1.8kg\;N\;ha^{-1}$, and the loss of N by ammonia volatilization was 2.0-2.3%. Loss of N by $NH_3$ volatilization with LCU treatment was reduced by 75-79% comparing to urea treatment.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.2
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• pp.71-84
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• 2004

There is a growing demand for agrometeorological information that end-users can use and not just interesting information. lo achieve this, each region/community needs to develop and provide localized climate and weather information for growers. Additionally, provide tools to help local users interpret climate forecasts issued by the National Weather Service in the country. Real time information should be provided for farmers, including some basic data. An ideal agrometeorological information system includes several components: an efficient data measuring and collection system; a modern telecommunication system; a standard data management processing and analysis system; and an advanced technological information dissemination system. While it is conventional wisdom that, Internet is and will play a major role in the delivery and dissemination of agrometeorological information, there are large gaps between the "information rich" and the "information poor" countries. Rural communities represent the "last mile of connectivity". For some time to come, TV broadcast, radio, phone, newspaper and fax will be used in many countries for communication. The differences in achieving this among countries arise from the human and financial resources available to implement this information and the methods of information dissemination. These differences must be considered in designing any information dissemination system. Experience shows that easy across to information more tailored to user needs would substantially increase use of climate information. Opportunities remain unexplored for applications of geographical information systems and remote sensing in agro meteorology.e sensing in agro meteorology.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.1
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• pp.1-7
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• 2011

In this study, we investigated the antioxidant activities, inhibition activity against ACE (angiotensin converting enzyme) and antitumor activity of extract from Acanthopanax senticosus HARMS fruits for development novel functional resources. In order to understand the factors responsible for the potent antioxidant and antihypertensive ability of fruits in A. senticosus, it has been evaluated for anti-oxidative activity using Fenton's reagent/ethyl linoleate system and for free radical scavenging activity using the l,l-diphenyl-2-picryl hydrazyl free radical generating system. The fruits extract of A. senticosus showed higher antioxidant activities than positive control, ${\alpha}$-tocopherol at all concentrations, while fruits extract of A. senticosus showed same degree of radical scavenging activity with positive control, ${\alpha}$-tocopherol. The ability of fruit extracts from A. senticosus to influence the inhibitory activity of angiotensin converting enzyme (ACE) and xanthine oxidase (XOase) has also been discussed. The activity of growth-inhibitory of fruit extracts of A. senticosus was screened by SRB (sulphorhodamine B) method on diverse cancer cells representing different types of cancers. The fruit extracts of A. senticosus showed moderate inhibition on proliferation of LNCaP and MOLT-4F cells and did not inhibit the proliferation of other cancer cells. The fruit extracts of A. senticosus inhibited the proliferation of cancer cells with $GI_{50}$ values ranging from 5 to $10{\mu}g/mL$. This result revealed that the fruit extracts of A. senticosus was expected to be good candidate for development into source of free radical scavengers, antihypertentive, and anti-tumor agent.

• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.96-102
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• 2012

This study was designed to evaluate a repeated oral dose toxicity and immunomodulating activity of $Pulsatilla$ $koreana$ and $Artemisiae$ $annuae$ in Sprague-Dawley rats. The female rats were treated with $Pulsatilla$ $koreana$ and $Artemisiae$ $annuae$ of control group, low group (0.5 ml/kg), medium group (1 ml/kg), high group (2 ml/kg) for distilled water, intragastrically for 4 weeks, respectively. To ensure the safety of $Pulsatilla$ $koreana $ and $Artemisiae$ $annuae$ such as the following were observed and tested. We examined the body weight, the feed intake, the clinical signs, the ophthalmological test, the hematological and the serum biochemical analysis. We also observed the histopathological changes of liver and kidney in rats. Hematological results were the increase of neutrophils, lymphocytes and monocytes in the high dose group of $Pulsatilla$ $koreana$. The increase immune cells in the high dose group of $Pulsatilla$ $koreana$ might immunomodulating activity. No significant differences in body weight, feed intake, serum biochemical analysis and histopathological between control and fed group were found. In conclusion, $Pulsatilla$ $koreana$ and $Artemisiae$ $annuae$ is physiologically safe and improve immunomodulating activity.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.1-15
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• 2017

Daecheong Reservoir was made by the construction of a large dam (>15 m in height) on the middle to downstream of the Geum River and the discharge systems have the watergate-spillway (WS), a hydropower penstock (HPP), and two intake towers. The purpose of this study was to investigate the limnological anomalies of turbid water reduction, green algae phenomenon, and oligotrophic state in the lower part of reservoir dam site, and compared with hydro-meteorological factors. Field surveys were conducted in two stations of near dam and the outlet of HPP with one week intervals from January to December 2000. Rainfall was closely related to the fluctuations of inflow, outflow and water level. The rainfall pattern was depended on the storm of monsoon and typhoon, and the increase of discharge and turbidity responded more strongly to the intensity than the frequency. Water temperature and DO fluctuations within the reservoir water layer were influenced by meteorological and hydrological events, and these were mainly caused by water level fluctuation based on temperature stratification, density current and discharge types. The discharges of WS and HPP induced to the flow of water bodies and the outflows of turbid water and nutrients such as nitrogen and phosphorus, respectively. Especially, when hypoxic or low-oxygen condition was present in the bottom water, the discharge through HPP has contributed significantly to the outflow of phosphorus released from the sediment into the downstream of dam. In addition, HPP effluent which be continuously operated throughout the year, was the main factor that could change to a low trophic level in the downreservoir (lacustrine zone). And water-bloom (green-tide) occurring in the lower part of reservoir was the result that the water body of upreservoir being transported and diffused toward the downreseroir, when discharging through the WS. Finally, the hydropower effluent was included the importance and dynamics that could have a temporal and spatial impacts on the physical, chemical and biological factors of the reservoir ecosystem.

• Journal of Animal Science and Technology
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• v.45 no.5
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• pp.749-758
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• 2003

The velvet antler of Korean sika deer has been used to the important resources for human health care with ginseng in Korea and Chinese. For studying on biological function of deer velvet being recorded in many ancient literatures, this experiment was conducted to evaluate the effects of powdered velvet antler on growth, feed intake, feed efficiency and intestinal organ development in growing and adult Sprague-Dawley Rats. Experiments were designed by adding amount of powdered velvet antler such as control (non- supplementation), powdered velvet antler I (PVA I, recommended dose) and powdered velvet antler II (PVA II, thrice recommended dose). The recommended dose of powdered velvet in this experiment was calculated with metabolic body weight of rats, which based on the recommended amounts for 70 kg of human. The growths of growing and adult rats generally appeared advantage in PVA supplementation. The final body weight of control, PVA I and II were respectively 470${\pm}$39.00g, 478${\pm}$30.33g and 475${\pm}$22.72g in growing rats, and 485${\pm}$38.50g, 521${\pm}$38.67g and 508${\pm}$34.44g in adult rats. The average daily feed intake were not significantly influenced but the feed efficiency ratios (feed/gain) were improved by PVA supplementation. The feed/gain ratios of control, PVA I and II were respectively 5.99, 5.47 and 5.54 in growing rats, and 9.04, 7.73 and 8.18 in adult rats. In case of developments of liver, heart, kidney and stomach, we obtained favorable results in both PAC I and II, but their results were not significantly different according to amount of PVA supplementation. Because liver and heart are important organs in the circulation of blood, their favorable effects suggest that velvet antler may have factors contributing hematopoiesis. Conclusively, supplementation of powdered velvet antler resulted in an improved growth, feed efficiency and development of some intestinal organs in growing and adult rat. Even if further investigation of dose in human health care are should be performed, this experiment appeared the best desirable results in PVA I, recommended dose of powdered velvet antler.