• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.268-276
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• 2018

BACKGROUND: In the month of January 2018, fine dust alerts and warnings were issued 36 times for $PM_{10}$ and 81 times for PM2.5. Air quality is becoming a serious issue nation-wide. Although interest in air-purifying plants is growing due to the controversy over the risk of chemical substances of regular air-purifying solutions, industrial spread of the plants has been limited due to their efficiency in air-conditioning perspective. METHODS AND RESULTS: This study aims to propose a vegetation-based bio-filter system that can assure total indoor air volume for the efficient application of air-purifying plants. In order to evaluate the quantitative performance of the system, time-series analysis was conducted on air-conditioning performance, indoor air quality, and comfort index improvement effects in a lecture room-style laboratory with 16 persons present in the room. The system provided 4.24 ACH ventilation rate and reduced indoor temperature by $1.6^{\circ}C$ and black bulb temperature by $1.0^{\circ}C$. Relative humidity increased by 24.4% and deteriorated comfort index. However, this seemed to be offset by turbulent flow created from the operation of air blowers. While $PM_{10}$ was reduced by 39.5% to $22.11{\mu}g/m^3$, $CO_2$ increased up to 1,329ppm. It is interpreted that released $CO_2$ could not be processed because light compensation point was not reached. As for the indoor comfort index, PMV was reduced by 83.6 % and PPD was reduced by 47.0% on average, indicating that indoor space in a comfort range could be created by operating vegetation-based bio-filters. CONCLUSION: The study confirmed that the vegetation-based bio-filter system is effective in lowering indoor temperature and $PM_{10}$ and has positive effects on creating comfortable indoor space in terms of PMV and PPD.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.283-290
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• 2018

BACKGROUND: Pesticide residue analysis is an essential activity in order to establish the food safety of agricultural products. Analytical approaches to the food safety are required to meet internationally the guideline of Codex (Codex Alimentarius Commission, CAC/GL 40). In this study, we developed a liquid chromatograph-tandem mass spectrometer (LC-MS/MS) method to determine the herbicide clopyralid in food matrixes. METHODS AND RESULTS: Clopyralid was extracted with aqueous acetonitrile containing formic acid and the extracts were mixed in a citrate buffer consisted of magnesium sulfate anhydrous, NaCl, sodium citrate dihydrate and disodium hydrogencitrate sesquihydrate followed by centrifugation. The supernatants were filtered through a nylon membrane filter and used for the analysis of clopyralid. The method was validated by accuracy and precision experiments on the samples fortified at 3 different levels of clopyralid. LC-MS/MS in positive mode was employed to quantitatively determine clopyralid in the food samples. Matrix-matched calibration curves were inearranged from 0.001 to 0.25 mg/kg with r2 > 0.994. The limits of detection and quantification were determined to be 0.001 and 0.01 mg/kg, respectively. There covery values of clopyralid for tified at 0.01 mg/kg in the control samples ranged from approximately 82 to 106% with relative standard deviations below 2 0%. CONCLUSION: The method developed in this study meets successfully the Codex guideline for pesticide residue analysis in food samples. This, the method could be applicable to determine pesticides in foods produced domestically and internationally.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.2
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• pp.61-67
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• 2019

This study was conducted to investigate the effect of supplementary feeding levels on livestck and forage productivity and grazing intensity in Elk stags (Cervus canadensis). A fifteen 2-year-old Elk stags about 195 kg were randomly assigned to one of three dietary treatments (five animals per treatment). The dietary treatments consisted of a feeding concentrate of 1.0% of body weight (T1), 1.5% of body weight (T2) and 2.0% of body weight. Total dry matter intake (TDMI) was increased with increased with an increasing supplementary feeding levels. Average daily gain (ADG) were significantly increased with an increasing supplementary feeding levels (p<0.05) and reached a maximum on July and was lower in spring than autumn. The velvet antler production was no differences among treatment groups. Forage productivity of pasture and crude protein content were highest on May and decreased thereafter, however, crude fiber content was the reversed. The grazing intensity of Elk stags was increased in spring (38 to 59 head per ha) than summer and autumn (13 to 32 head per ha). The average grazing intensity of Elk stags ranged from 21 to 34 head per ha, which is affected by supplementary feeding levels. This result suggests that feeding supplementary diet at 1.5 % of body weight was needed to maintain the stable wight gain in antler growing periods and control the proper grazing intensity of Elk deer stags.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.197-203
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• 2019

This study was carried out to investigate the effect of chlorine water and plasma gas treatment on the quality and microbial control of Latuca indica L. baby Leaf during storage. Latuca indica L. baby leaves were harvested from a plant height of 10cm. They were sterilized with $100{\mu}L{\cdot}L^{-1}$ chlorine water and plasma-gas (1, 3, and 6hours), and packaged with $1,300cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ films and then stored at $8{\pm}1^{\circ}C$ and RH $85{\pm}5%$ for 25days. During storage, the fresh weight loss of all treatments were less than 1.0%, and the carbon dioxide and oxygen concentrations in packages were 6-8% and 16-17%, respectively for all treatments in the final storage day. The concentration of ethylene in the packages fluctuated between $1-3{\mu}L{\cdot}L^{-1}$ during the storage and the highest concentration of ethylene was observed at 6 hours plasma treatment in the final storage day. The off-odor of all treatments were almost odorless, the treatments of chlorine water and 1 hour plasma maintained the marketable visual quality until the end of storage. Chlorophyll content and Hue angle value measured at the final storage day were similar to those measured before storage in chlorine water and 1 hour of plasma treatments. E. coli was not detected immediately after sterilization in all sterilization treatments. After 6 hours of plasma treatment, the total bacteria fungus counts were lower than the domestic microbial standard for agricultural product in all sterilization treatments. The total aerobic counts in the end storage day increased compared to before storage, whereas E. coli was not detected in all sterilization treatments. The sterilization effect against bacteria and fungi was the best in chlorine water treatment. Plasma treatment showed sterilization effects, but within a prolonged period of time. In addition, the sterilization effect decreased gradually. These results suggest that chlorine water and plasma treatment were effective in maintaining Latuca indica L. baby Leaf commerciality and controlling microorganisms during postharvest storage.

• Korean Journal of Heritage: History & Science
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• v.52 no.1
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• pp.272-287
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• 2019

The Korean Demilitarized Zone (DMZ) was established in 1953 by the Korean War Armistice Agreement. It extends from the estuary of the Imjin River, in the west, to the coast of the East Sea. It is 4 km in width and 148 km in length. However, the ecosystems of the civilian control zone (CCZ) located between the southern border of the DMZ and the civilian control line (CCL) and the CCZ in the estuary of the Han River and the Yellow Sea are similar to those in the DMZ, and, therefore, the ecosystems of the DMZ and the CCZ are collectively known as the "ecosystems of the DMZ and its vicinities." The flora in the DMZ and its vicinities is composed of 1,864 species, which accounts for about 42% of all the vascular plant species on the Korean Peninsula and its affiliated islands. Conducting a detailed survey on the vegetation, flora, and fauna in the DMZ is almost impossible due to the presence of landmines and limitations on the time allowed to be spent in the DMZ. However, to assess the environmental impact of the Munsan-Gaesong railroad reconstruction project, it was possible to undertake a limited vegetation survey within the DMZ in 2001. The vegetation in Jangdan-myeon, in Paju City within the DMZ, was very simple. It was mostly secondary forests dominated by oaks such as Quercus mongolica, Q. acutissima, and Q. variabilis. The other half of the DMZ in Jangdan-myeon was occupied by grassland composed of tall grasses such as Miscanthus sinensis, M. sacchariflorus, and Phragmites japonica. Contrary to the expectation that the DMZ may be covered with pristine mature forests due to more than 60 years of no human interference, the vegetation in the DMZ was composed of simple secondary forests and grasslands formed on former rice paddies and agricultural fields. At present, the only legal protection system planned for the DMZ is the Natural Environment Conservation Act, which ensures that the DMZ would be managed as a nature reserve for only two years following Korean reunification. Therefore, firstly, the DMZ should be designated as a site of domestic legally protected areas such as nature reserve (natural monument), scenic site, national park, etc. In addition, we need to try to designate the DMZ as a UNESCO Biosphere Reserve or as a World Heritage site, or as a Ramsar international wetland for international cooperation. For nomination as a world heritage site, we can emphasize the ecological and landscape value of the wetlands converted from the former rice paddies and the secondary forests maintained by frequent fires initiated by military activities. If the two Koreas unexpectedly reunite without any measures in place for the protection of nature in the DMZ, the conditions prior to the Korean War, such as rice paddies and villages, will return. In order to maintain the current condition of the ecosystems in the DMZ, we have to discuss and prepare for measures including the retention of mines and barbed-wire fences, the construction of roads and railroads in the form of tunnels or bridges, and the maintenance of the current fire regime in the DMZ.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.4
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• pp.12-23
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• 2019

This study was carried out to investigate and analyze the environmental characteristics of restoration areas in the riparian zones of the Han River, and to quantify the amount of topsoil organic carbon storage. As a result of investigation and analysis of 21 survey sites, the total number of species planted was found to be 17, and the mean number of species was $2.86{\pm}0.13$ species per site. At least one species and a maximum of 7 species were planted at each site. The mean diameter at breast height was $9.1{\pm}0.6cm$, the mean height was $6.2{\pm}0.3m$ and the root content in soil was $0.13{\pm}0.18g/cm^2$. As a result of the analysis of the soil characteristics, 6 out of 21 items, such as the bulk density, solid ratio, gravel ratio, soil hardness, sand content, and pH increased as the soil layer deepened. The topsoil organic carbon storage by layer was $11.54{\pm}1.08ton/ha$ at 0-10cm, $8.69{\pm}0.81ton/ha$ at 10-20cm, $7.97{\pm}0.79ton/ha$ at 20-30cm, and the total from 0 to 30cm was $28.21{\pm}7.31ton/ha$. The highest amount of topsoil organic carbon storage by land use in the past was $35.17{\pm}5.31ton/ha$ in agricultural lands, followed by $28.16{\pm}8.31ton/ha$ in residential areas, $21.87{\pm}9.05ton/ha$ in commercial areas, $19.23{\pm}12.48ton/ha$ in industrial areas, and $17.07{\pm}11.33ton/ha$ in the barren areas. The highest amount of topsoil organic carbon storage in the restored areas was $38.46{\pm}3.14ton/ha$ in 2006, followed by $28.57{\pm}7.84ton/ha$ in 2016, and $16.78{\pm}6.06ton/ha$ in 2011. The results of this study are expected to provide a basic database and evaluation criteria for enhancing the carbon abatement effects of the restoration sites in riparian zones in the future.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.2
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• pp.31-40
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• 2019

In Korea, 51,013 thousand tons of livestock manure was generated in 2018. A total of 46,530 thousand tons, which is 91.2% of the total amount of livestock manure generated, was treated by composting(40,647 thousand tons) or liquid fertilization(5,884 thousand tons) method. At present, the policy of livestock manure treatment in Korea is to make livestock manure into organic fertilizer(compost, liquid fertilizer) and then to applicate it on agricultural land. And this policy is very effective in terms of livestock manure treatment and nutrient recycling. However, considering the steadily declining farmland area for decades, the use of livestock manure compost could be limited in the future. There is also concern that local nutrient overloading, nutrient management regulation, and restrictions on the number of livestock may become serious problem for livestock manure treatment. In addition, there are some opinions that nutrient derived from livestock manure may flow into tributaries of major dams. In recent years, there has been a suspicion that fine dust may be generated from livestock manure compost. In recent years, the use of livestock manure fertilizer has been rapidly increasing, there is a growing demand of the development of new technologies for livestock manure treatment. Especially, cow excretes a larger amount of manure than other livestock, so that the efficiency of development of new technology for cow manure treatment will be high. Therefore, in this study, the combustion characteristics of cow manure pellet were investigated in order to analyzed whether cow manure could be used as source of solid fuel. During the combustion test, the weight loss of the cow manure pellet began to increase when the temperature of the combustion chamber reached $300^{\circ}C$. The ratio of $H_2$, $CH_4$, CO in the pyrolysis gas produced in the pyrolysis process of cow manure pellet were 6.65~11.62%, 0.58~1.54 and 11.47~14.07%, respectively.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.639-645
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• 2018

The objective of the study is to analyze the impact of zone adjustment by comparing the changes from 2011 to 2018 of social and environmental factors such as the special-purpose area, actual construction activities including building development, land use environment, and officially assessed individual land price in the areas released from the National Park Zone during the second National Park Zone adjustment during 2010 to 2011 with the social and environmental factors in the areas that remained in the National Park Zone during the same period. We intended to investigate the problems of the second National Park Zone adjustment and explore alternative implications for the third National Park Zone adjustment. As for the special-purpose area, 80.4% of the released areas were converted to planned, production, and conservation area while 15.6% changed to the agricultural area, and 4.0% remained as the natural environmental conservation area. Regarding the change in building development scale, the average size of construction in the released area since 2011 was $106m^2$ while that in the retained areas was $91m^2$. For the land use environment, the rate of change from the natural area to developed area was 1.9% in the released area and 0.7% in the retained area. The officially assessed individual land price increased by 11,911 won in the released area and 4,413 won in the retained area. Although both areas showed an increase in the land price, the difference of officially assessed individual land prices was about 2.5 times. The problem concerning the private property rights of local residents in the national parks is still a challenge, but the second National Park Zone adjustment has resolved the problem significantly. Accordingly, it is necessary to offer the benefits for the residents in the national park area by analyzing the park zoning and park facility planning to present the rational alternative. It is also necessary to establish a support system that encourages the collaborative cooperation between the park authority and residents and assures that the residents to have pride in the national park.

• Journal of the Korean Society of International Agriculture
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• v.30 no.4
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• pp.313-319
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• 2018

The purpose of this study was to provide the basis for the vegetable seedlings export research and policy establishment by analyzing vegetable seedlings export status from the agricultural quarantine statistics in Korea and the changes of temperature and relative humidity during the vegetable seedlings shipping export transportation to Japan. From 2007 to 2016, various vegetable seedlings such as cabbage, tomatoes, cucumber, onion and etc., have been exported to more than 20 countries around the world. The main exporting country of vegetable seedlings for commercial purposes is Japan, and the major exported seedlings to Japan in 2016 were fruit vegetable grafted seedlings such as eggplant, tomato, cucumber, watermelon and pepper. Total export amount of the fruit vegetable seedlings to Japan in 2016 were 2,575,446 seedlings and it is approximately 0.7 to 1.6 million dollars. The grafted seedlings exported to Japan were consumed for urban agriculture and farm use. Shipping transportation took about 24 hours in the process of receiving the package ${\rightarrow}$ shipment ${\rightarrow}$ quarantine (Busan port) ${\rightarrow}$ Quarantine (Japan Shimonoseki Port). The growing demand for vegetable seedlings due to the development of urban agriculture in Japan and the growing interest and demand for vegetable grafting seedlings in neighboring countries such as Russia will be an opportunity to expand the export size of Korean vegetable grafting seedlings. In order to expand the export of vegetable seedlings in Korea, it is necessary to ensure further active government policy and research on the production of export seedlings, seedlings storage and transportation technology and analysis of exporting countries' market information.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.4
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• pp.266-272
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• 2018

In this study, we created grassland establishment(paddock No.39), grassland improvement(Paddock No.44), and tall fescue seeding(paddock No.64), and the rate botanical composition, DM yield, nutritive value were examined through 2016 to 2017. The rate of botanical composition was 81% in 2016, 75% in 2017, up to 21% higher than No.39 67%, 60%, No.44 58% and 54%. The annual average DM yield was the highest at 13,234kg/ha in the district, followed by No.39, No.44, followed by 10,636kg/ha and 10,235kg/ha, respectively. The crude protein content was the highest at No.39 12.16%, with No.44 and No.64 showing 10.7%, respectively. NDF content (average for two years) was 55.90% in No.44 and No.39, slightly lower than 58.42% and 57.00%, respectively. The two-year ADF average content was 31.07% for the same trend as the NDF capacity in the No.44, below 31.71% and 32.65%, respectively. To sum up the results, Although there was a high level of incentive sowing plot(No.39) in nutritive value, considering the botanical composition and productivity of the pasture, it is also deemed desirable to have a tall fescue plot(No.64).