• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.22-28
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• 2012

This experiment was conducted to find out high antioxidant activity varieties of chinese matrimony from the 131 accessions which conserved at Cheongyang Gugija Experiment Station. The status of the 131 accessions were composed 21 of local varieties, 20 of introduced species and 90 of improved races. The anti-oxidant activity using DPPH and $IC_{50}$, 45 accessions out of 90 showed high activity in free radical scavenging ability as less than $200{\mu}g/m{\ell}$ in improved races, while nine and six accessions from the introduced species and local varieties, respectively. At the stem part, the highest three anti-oxidant varieties among 131 accessions are "C0148-94", "D0148-72" and "Cheongdae", while China collection 1 in leaf part. Since "Cheongdae" is the progeny from the "Cheongyang Jaerae 5" and "Myungan" and those two varieties, "C0148-94" and "D0148-72" are from the Myungan and Cheongdae, high anti-oxidant activity can be inherited in Chinese matrimony vine.

• Journal of Korea Water Resources Association
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• v.39 no.4 s.165
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• pp.299-311
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• 2006

In this paper it is outlined the methodology of estimating the parameters of water balance analysis method for calculating recharge, using ground water level rises in monitoring well when values of specific yield of aquifer are not available. This methodology is applied for two monitoring wells of the case study area in northern area of the Jeiu Island. A water balance of soil layer of plant rooting zone is computed on a daily basis in the following manner. Diect runoff is estimated by using SCS method. Potential evapotranspiration calculated with Penman-Monteith equation is multiplied by crop coefficients($K_c$) and water stress coefficient to compute actual evapotranspiration(AET). Daily runoff and AET is subtracted from the rainfall plus the soil water storage of the previous day. Soil water remaining above soil water retention capacity(SWRC) is assumed to be recharge. Parameters such as the SCS curve number, SWRC and Kc are estimated from a linear relationship between water level rise and recharge for rainfall events. The upper threshold value of specific yield($n_m$) at the monitoring well location is derived from the relationship between rainfall and the resulting water level rise. The specific yield($n_c$) and the coefficient of determination ($R^2$) are calculated from a linear relationship between observed water level rise and calculated recharge for the different simulations. A set of parameter values with maximum value of $R^2$ is selected among parameter values with calculated specific yield($n_c$) less than the upper threshold value of specific yield($n_m$). Results applied for two monitoring wells show that the 81% of variance of the observed water level rises are explained by calculated recharge with the estimated parameters. It is shown that the data of groundwater level is useful in estimating the parameter of water balance analysis method for calculating recharge.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.261-268
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• 2010

This study was conducted to investigate the effects of environmental temperature (ET; $21^{\circ}C$ and $32^{\circ}C$) and antibiotic substitute conditions on meat quality of chicken breast during cold storage. Seven treatments were as follows; T1, ET $21^{\circ}C$ + antibiotics (+); T2, ET $21^{\circ}C$ + antibiotics (-); T3, ET $32^{\circ}C$ + antibiotics (+); T4, ET $32^{\circ}C$ + antibiotics (-); T5, ET $32^{\circ}C$ + 0.1% Lactobacillus; T6, ET $32^{\circ}C$ + 0.1% medicinal plant extract; T7, ET $32^{\circ}C$ + 0.1% essential oil. T7 had a higher (p<0.05) pH at 72 h post-slaughter value when compared to the other treatments. The CIE $b^*$ value of treatments at ET $32^{\circ}C$ showed significantly (p<0.05) higher when compared to the treatments at $21^{\circ}C$. T7 also had significantly (p<0.05) lower TBARS values than the other treatments as the storage time increased. T6 contained significantly (p<0.05) higher extractability of salt-soluble protein contents than the other treatments. The results from SDS-PAGE showed that the actin protein decreased for ET treatments at $32^{\circ}C$. The concentration of actin protein was not significantly different among T1, T2 and T7. Therefore, these result suggested that the antibiotic alternative with essential oil was effective under the high environmental temperature ($32^{\circ}C$) for chicken meat production.

• Journal of Korea Port Economic Association
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• v.30 no.1
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• pp.175-194
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• 2014

Because the thawing of the Arctic ocean is slowly accelerating due to global warming, recently exploring resources in Arctic ocean and transporting resources by using the North Pole route have been getting spotlight. Since the original route transported by the Suez Canal from Korea to Europe could be shorten about 8,000km in distance(decreased about 38% compared to the original route), which means shortening about 10 voyage dates, it is expected to bring huge logistics cost reduction. Once the North Pole route is commercialized successfully, it would be one of the most important variables that affects future of Busan port and guides for economic development of Busan. Therefore, the purpose of this study is to analyze Busan port and the economic growth of Busan area by researching promising industry, based on the effect of freight transporting by the Northern sea route on the economy of Busan. For this study, questionnaire surveys and interviews were conducted for 64 people of experts in the shipping and port industry, relevant government, and academics. The survey finding shows that port logistics industry is a promising business in Busan in terms of its growth and competitiveness. It is necessary to develop feeder network facilities that prepare for commercialization of the Northern sea route as a short and medium term plan and provide professional manpower training in polar regions. Ship supply business would also play an important role. It is identified that revitalization of shipbuilding and ocean plant industry should be done in terms of Arctic business. With regard to the fishery industry it is found that modernization of fishery ship and development of fishery equipment used in polar areas should be carried out.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.1
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• pp.123-130
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• 2011

Objectives of this study were to compare the environmental effects of digestates produced in bioenergy village on the rice paddy field for recycling. Digestates were applied to the soils and the soil properties and the crop responses were analyzed according to the standard methods of soil evaluation. Plant height and the number of tiller showed similar results in both the conventional and digestate treated field, and the yield of rough rice was higher in the field treated with digestates than that with chemical fertilizer. The amounts of nitrogen absorbed in straw and grain were larger in the digestates-treated field than chemical fertilizer-treated one, and efficiency of nitrogen applied was shown to be the highest in 100% treated digestate of the pig manure. Exchangeable cation and pH increased in the soil treated with digestate after harvesting, but salt was not accumulated. With these results, it was concluded that resource recycling in green town can be facilitated through the securement of arable lands for the application of digestates and the proper use of these fertilizers. Long-term effects of digestate application on the soil environment should be sustainingly studied.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.1
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• pp.39-48
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• 2019

Objective of this study was to evaluate an optimum biochar application rate and estimate the carbon sequestration based on the soil chemical properties and growth responses for biochar application during tomatoes cultivation. The treatments consisted of control as recommended application rates of fertilizers, 0.01%, 0.03%, 0.05%, and 0.07% of biochar application(w/w, biochar:soil). For effects of soil chemical properties, the $NO_3-N$contents in the soil were peaked at 9 days after transplanting. But there was not significant difference(p>0.05) among the treatments during cultivation periods. However, $NH_4-N$ contents in the biochar treatment were lower than the control until 14 days of transplanting. $P_2O_5$ contents in the biochar treatments were lower than that of the control until 19 days after transplanting except 0.01% of biochar application plot. $K_2O$ contents in soils treated with 0.01% and 0.03% of biochar were higher until 6 days after transplanting than that in the control. For N use efficiency of biochar application, it was observed that the 0.05% biochar application plot was highest among the treatments. The highest carbon sequestration was estimated at $2.83mg\;kg^{-1}$ for 0.03% of biochar application. However, it is considered that the optimum biochar application rate was 0.05% for tomato cultivation, considering the growth characteristics and yield components.

• Korean Journal of Environment and Ecology
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• v.33 no.1
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• pp.28-51
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• 2019

The purpose of this study was to analyze forest vegetation structure in Marugeum (the ridge line) area between Dakmokryeong and Daetjae in Baekdudaegan through vegetation classification, importance value, species diversity, and CCA using the data that were collected from 245 quadrates through Braun-Blanquet vegetation survey method from May to September in 2017. The results of the forest vegetation classification identified 8 vegetation units with Quercus mongolica community group at the highest level. Q. mongolica community group was classified into the Cornus controversa community, Buxus koreana community, Sasa borealis community, Abies nephrolepis community, and Q. mongolica typical community. C. controversa community was further classified into Quercus dentata group, Filipendula glaberrima group, Larix kaempferi group, and C. controversa typical group. The result of the important value analysis showed that Q. dentata had the highest importance value at 19.1% in vegetation unit 1 while Q. mongolica had the highest importance value at 22.7%, 38.3%, 25.6%, 41.3%, 27.9%, and 41.6% in vegetation unit 2, 4, 5, 6, 7, and 8, respectively, and L. kaempferi had the highest importance value at 27.6% in vegetation unit 3. As such, Q. mongolica species generally represented the communities of Marugeum (the ridge line) area of Dakmokryeong to Daetjae in Baekdudaegan. The results of species diversity showed that vegetation unit 1 and 2 were 3.305 and 3.236, respectively, which were relatively higher than other vegetation units. It was considered that this result was due to the influence of high emergence of present species. The results of the CCA analysis of the correlations between biotic environmental factors and vegetation types showed that vegetation unit 1 was mainly correlated with the megaphanerophyte ratio and vine plant ratio. In the correlations between abiotic environmental factors and vegetation types, vegetation unit 7 was significantly correlated with altitude. From the perspective of ecological management, vegetation unit 5 represented by B. koreana community was inhabited by a variety of plants due to the species composition and location environment due to the geological characteristics that are typical of limestone area. Vegetation unit 7 represented by A. nephrolepis community was typified as subalpine vegetation widely distributed by relict species and endemic species. We concluded that it is necessary to manage these vegetation units with an ecologically differentiated approach.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.361-377
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• 2018

The aim of this study was to examine whether the guideline by the Ministry of Environment (ME) successfully and appropriately applied the IUCN Red List criteria at regional level and the rare and endangered national list considered eligible. A certain number of vascular plants, which are widely distributed in the world or in east Asia, deemed to be ineligible for assessment at a regional level as Not Applicable category (NA), because it occurs at very low numbers in South Korea. Among 377 vascular plant taxa evaluated by the ME, NA included 238 species, which represented 63.1%. The number of synonymized species or illegitimate name species were 13 species, which accounted for 3.4%. 21 species (9.3%) were threatened at global level and 103 species were possibly candidates species list for Red List assessments at regional level in the near future. The proportion of NA or waiting list was 66.6% among the list assessed by the ME. The most common errors involved incorrectly application of species extinction in case of population extinction in South Korea to the assessment and provided incorrect interpretation of the Red List criteria at regional level. The most assessments proposed by ME were not backed up without quantitative data quality, justifications, and sources. It is suggested that the risk of extinction should be reassessed at least in the Korean peninsula within the light of their overall distribution including far eastern Russia and North eastern China in north and for Japan and Taiwan in south for regional assessment. The results obtained here using the IUCN criteria at regional level showed that the list proposed by the ME produced an overestimation of the number of threatened vascular plants. Also, the misapplication of the term 'species extinction' for regional assessment was open to some degree of subjectivity and misinterpretation.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.440-446
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• 2019

This study examined the growth and fruiting characteristics and the acorns biomass allometric equation of Quercus acuta to provide reference data related to the growth and seed supply during the restoration of evergreen forest in the warm temperate zone in Wando Island, Korea. For the growth survey, we selected and cut three sample trees having a mean diameter at breast height (DBH) to investigate the growth analysis through a stem analysis. We then developed the allometric equation (Y=aX+b) of DBH and tree height growth characteristic (Y) according to the average tree age (X) of sampled trees and estimated the DBH and tree height according to the age of Quercus acuta. For the fruiting survey, we selected and cut three sample trees with full fruit in August when, they are at the early mature fruiting stage, for the analysis. To develop the acorns/tree biomass allometric equation of Quercus acuta, we selected and cut ten sample trees of evenly divided diameters. The acorns biomass allometric equation ($Y=aX^b$) was derived by analyzing the biomass (Y) and the growth characteristics (X), such as the DBH, tree height, crown width, and crown height. The allometric equations of average tree age according to DBH and tree height were Y=0506X-2.064 ($R^2=0.999$) and Y=0.321X+0689 ($R^2=0.992$), respectively. The developed allometric equations estimated that the DBH were 3.0cm, 8.1cm, 13.1cm and 18.2cm while the tree heights were 3.9m, 7.1m, 10.3m, and 13.5m when the tree ages were 10, 20, 30, and 40 years, respectively. The analysis results of fruiting characteristics showed that the length, the diameter, the number of fruits, and the number of acorns per fruiting branch had the statistically significant difference and tended to decrease from the upper part to the lower part of crown downward. The total number of acorns was 1,312 acorns/tree in the upper part, 115 acorns/tree in the middle part, and 5 acorns/tree in the lower part of the crown. The allometric equation for the amount of acorns with DBH as an independent variable was $Y=0.003X^{4.260}$ with the coefficient of determination at 0.896. Although the coefficient of determination of the allometric equation using only DBH as the independent variable was lower than that using DBH and tree height ($D^2H$), it would be more practical to consider only DBH as the independent variable because of measurement errors.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.5-13
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• 2022

The current environmental problem is that environmental pollution is accelerating due to the generation of large amounts of waste and indiscriminate consumption of energy. Fossil fuels, a representative energy production fuel, are burned in the process of producing energy, generating a large amount of greenhouse gases and eventually causing climate change. In addition, the amount of waste generated worldwide is continuously increasing, and environmental pollution is occurring in the process of waste treatment. One of the methods for simultaneously solving these problems is the energy recovery from and reduction of organic wastes. Sewage sludge generated in sewage treatment plants has been treated in various ways since ocean disposal was completely prohibited, but the amount generated has been continuously increasing. Since the sewage sludge contains a large amount of organic materials, it is desirable to recover energy from the sewage sludge and reduce the final discharged waste through anaerobic digestion. However, most of the excess sludge is a mass of microorganisms used in sewage treatment, and in order for the excess sludge to be anaerobically digested, the cell walls of the microorganisms must be destroyed first, but it takes a lot of time to destroy the cell walls, so high rates of biogas production and waste reduction cannot be achieved only by anaerobic digestion. Therefore, the pre-treatment process of solubilizing excess sludge is required, and the thermal solubilization process is verified to be the most efficient among various solubilization methods, and high rates of biogas production and waste reduction can be achieved by anaerobic digestion after destroying cell walls the thermal solubilization process. In this study, when pretreating TS 10% thickened excess sludge through a thermal solubilization system, a study was conducted on solubilization characteristics according to retention time and operating temperature variables. The experimental variables for the retention time of the thermal solubilization system were 30 minutes, 60 minutes, 90 minutes, and 120 minutes, respectively, while the operating temperature was fixed at 160℃. The soulbilization rates calculated through TCOD and SCOD derived from the experimental results increased in the order of 12.11%, 20.52%, 28.62%, and 31.40%, respectively. And the variables according to operating temperature were 120℃, 140℃, 160℃, 180℃, and 200℃, respectively, while the operating retention time was fixed at 60 minutes. And the solubilization rates increased in the order of 7.14%, 14.52%, 20.52%, 40.72%, and 57.85%, respectively. In addition, TS, VS, T-N, T-P, NH₄⁺-N, and VFAs were analyzed to evaluate thermal solubilization characteristics of thickened excess sludge. As a result, in order to obtain 30% or more solubilization rate through thermal solubilization of TS 10% thickened excess sludge, 120 minutes of retention time is required when the operating temperature is fixed to 160℃, and 170℃ or more of operating temperature is needed when the operating time is fixed to 60 minutes.