• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.673-681
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• 2020

Human enteric Adenovirus 41 (HueAdV-41) is a major waterborne virus that causes human gastroenteritis and is classified as a viral group I double-strand DNA virus, Adenoviridae. HueAdV-41 has been detected with the polymerase chain reaction (PCR) in various samples such as ground water. However, the PCR-based diagnostic method has problems such as reaction time, sensitivity, and specificity. Thus, the loop-mediated isothermal amplification (LAMP) assay has emerged as an excellent method for field applications. In this study, we developed a LAMP system that can rapidly detect HueAdV-41 with high specificity and sensitivity. HueAdV-41 specific LAMP primer sets were tested through a specific, non-specific selection and sensitivity test for three prepared LAMP primer sets, of which only one primer set and optimum reaction temperature were selected. The developed LAMP primer set condition was confirmed as 63℃, and the sensitivity was 1 copy. In addition, to confirm the system, a LAMP positive reaction was developed with the restriction enzyme Taq I (T/GCC). The developed method in this study was more specific, rapid (typically within 2 - 3 hours), and highly sensitive than that of the conventional PCR method. To evaluate and verify the developed LAMP assay, an artificial infection test was done with five cDNAs from groundwater samples, and the results were compared to those of the conventional PCR method. We expect the developed LAMP primer set will be used to diagnose HueAdV-41 from various samples.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.519-519
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• 2016

Upper Chenab Canal (UCC) is a non-perennial canal in Punjab Province of Pakistan which provides irrigation water only in summer season. Winter and summer are two distinct cropping season with an average rainfall of about 161 mm and 700 mm respectively. Wheat-rice is common crop rotation being followed in the UCC command area. During winter season, groundwater and rainfall are the main sources of irrigation while canal and ground water is used to fulfil the crop water requirements (CWR) during summer. The objective of current study is to estimate how the irrigation water requirements (IWR) of the two crops are going to change under different conditions of temperature and rainfall. For this purpose, 12 different climatic scenarios were designed by combining the assumptions of three levels of temperature increase under dry, normal and wet conditions of rainfall. Weather records of 13 years (2000-2012) were obtained from PMD (Pakistan Meteorological Department) and CROPWAT model was used to simulate the IWR of the crops under normal and scenarios based climatic conditions. Both crops showed a maximum increase in CWR for temperature rise of $+2^{\circ}C$ i.e. 8.69% and 6% as compared to average. Maximum increment (4.1% and 17.51% respectively) in IWR for both wheat and rice was recorded when temperature rise of $+2^{\circ}C$ is coupled with dry rainfall conditions. March & April during winter and August & September during summer were the months with maximum irrigation requirements. Analysis also showed that no irrigation is needed for rice crop during May and June because of enough rainfall in this area.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.1039-1048
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• 2020

Food waste causes various economic losses and environmental pollution problems such as soil pollution and groundwater pollution. Food waste has been used as a resource in various forms and has been used mostly for feed and composting. This study compared microalgal nutrient medium (BG-11) with food waste compost to determine the possibility of using it as a culture medium. Scenedesmus quadricauda was isolated and cultured in an eutrophic reservoir and incubated for 3 days in distilled water before laboratory use. Food waste compost was produced in two food waste processing facilities, and hot water was extracted in the laboratory to be used for microalgae cultivation. The growth curve of the microalgae was analyzed based on the Chl-a concentration measured during the experiment, and the growth rate of the microalgae grown in the food waste compost was compared with the growth rate of those grown in the nutrient medium. Food waste compost showed a similar growth rate to that of the nutrient medium, and there was a difference depending on the manufacturing facility. The growth of microalgae in such food waste was further amplified when trace elements were added and showed better growth than that of the nutrient media. Particularly, when trace elements were added, the growth rate increased, and the growth period was further extended. Therefore, food waste compost can be sufficiently utilized as a microalgal culture medium, and if trace elements are added, it is considered that microalgae can be more effectively cultured compared to the existing nutrient medium.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.483-498
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• 2022

Soil moisture is defined as water in the pores of the soil's unsaturated zone, and it is closely related to various hydrological processes. This study aims to provide meaningful data by identifying factors affecting soil moisture through comparing soil moisture content and soil permeability in a study area covering six different land use types in an agricultural region that is highly dependent on groundwater. We conduct auto-correlation analysis, spectral density analysis, and cross-correlation analysis using time-series data. Soil moisture content shows to have weak auto-correlation and memory effects, and precipitation appears to have a substantial influence on soil moisture content. Saturation hydraulic conductivity does not vary markedly with changing land use, and instead appears to be affected by the inhomogenous soil structure.

• Journal of Korean Society of Rural Planning
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• v.24 no.3
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• pp.73-86
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• 2018

Agricultural or rural landscape provides various ecosystem services. However, the ecosystem services function is declining due to various environmental problems such as climate change, land use change, stream intensification, non-point pollution and garbage. The A1B scenario predicts that the mean air temperature of South Korea will rise $3.8^{\circ}C$ degrees celsius in 2100. Agricultural sector is very vulnerable to climate change, so it must be thoroughly predicted and managed. In Korea, the facility horticulture complex is 54,051ha in 2016 and is the 3rd largest in the world(MAFRA, 2014). Facilities of horticultural complexes are reported to cause problems such as groundwater decrease, vegetation and insects diversity reduction, landscapes damage and garbage increase, compared with the existing land use paddy fields. Heat island phenomenon associated with climate change is also accelerated by the high heat absorption of horticultural sites. Therefore, we analyzed the heat island phenomenon occurring in the facility of horticultural complex in Korea. As an improvement measurement, I examined how much air temperature is reduced by putting the channel and the open space. In the case of the Buyeo area, the Computational Fluid Dynamics (CFD) simulation was analyzed for the average summer temperature distribution in the current land use mode at $38.9^{\circ}C$. As an improvement measurement, CFD simulation after 10% of 6m water channel was found to have an effect of lowering the summer temperature of about $2.7^{\circ}C$ compared with the present average of $36.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $34.7^{\circ}C$, which is $4.2^{\circ}C$ lower than the present. For the Jinju area, CFD simulations were analyzed for the average temperature of summer at $37.8^{\circ}C$ in the present land use pattern. As an improvement measure, CFD simulations after 10% of 6m water channel were found to have an effect of lowering the summer temperature of about $2.6^{\circ}C$ compared to the current average of $35.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $33.9^{\circ}C$, which is $3.9^{\circ}C$ lower than the present. It can be said that the effect of summer temperature drop in open space and waterway has been proven. The results of this study are expected to be reflected in sustainable agriculture land use and used as basic data for government - level policy in land use planning for climate change.

• Korean Journal of Environmental Agriculture
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• v.25 no.1
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• pp.64-70
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• 2006

This study was conducted to investigate the concentration of fertigation for optimum yield and soil management of tomato cultivation in soils with different Electrical conductivity (EC) level under PE film house. The EC levels of soil were adjusted to 1.4, 3.0 and 5.4 dS/m and fertigation concentrations were supplied with 0.0 (groundwater), 1.0, 2.0 and 3.0 dS/m, respectively. When the concentration of fertigation was supplied over 3.0 dS/m to soil with EC 1.4 dS/m, the concentrations of $NO_3-N,\;avail.-P_2O_5$, and exchangeable K in soil were increased after the experiment. When fertigation concentration was supplied over 2.0 and 1.0 ds/m to soil with EC 3.0 and 5.4 dS/m respectively, the nutrient were also accumulated in the soil. Thus, the optimum concentrations of fertigation for optimum yield and soil management for tomato cultivation were recommended $1.0{\sim}2.0dS/m$, 1.0 dS/m and ground water (0.0 dS/m) to soils with EC 1.4, 3.0 and 5.4 dS/m, respectively. The fruit weight marketability and marketable yield of tomato were not significant among the treatments at 5% level by LSD. The concentrations of T-N, $P_2O_5\;and\;K_2O$ in tomato leaf were increased with increasing of fertigation concentration whereas the concentrations of CaO and MgO decreased with increasing of fertigation concentration.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.123-127
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• 2015

Wood piles are rarely used in the construction of a greenhouse in Korea, but they are relatively more often used in other countries, such as the Netherlands. There are several advantages associated with wood piles: they are more cost-effective, less time-consuming, and more ecofriendly than the steel pipes (SPs) and pre-stressed highstrength (PHC) piles. However, one of the limiting conditions is that they have to be installed below the groundwater level to prevent decay. Since the groundwater levels are generally high in the reclaimed lands in Korea, wood piles are expected to be used often as reinforcements for foundations of greenhouses in these areas. In this study, we measured the uplift capacities of wood piles through in-situ uplift capacity tests with an aim to provide basic design data for wood pile foundations. In order to test their applicability, we then compared these experimentally measured ultimate uplift capacities with the ones calculated through some of the existing theoretical equations. The wood piles used in the loading tests were made of softwood (pine wood), and the tests were performed using piles with different diameters (∅25cm and ∅30cm) and embedded depths (1m, 3m, and 5m). The test results revealed that the uplift capacity of the wood piles showed a clear linearly increasing tendency in proportion to the embedded depth, with the ultimate uplift capacities for the diameters 25cm and 30cm being 9.38 and 10.56tf, respectively, at the embedded depth of 5m; thus demonstrating uplift capacities of ${\geq}9tf$. The comparison between the actually measured values of the uplift capacity and the ones calculated through equations revealed that the latter, which were obtained using the ${\alpha}$ method, were generally in an approximate agreement with the in-situ measured values.

• Korean Journal of Organic Agriculture
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• v.4 no.2
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• pp.97-136
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• 1995

Recendtly an organic agricultured in Korea is getting a public attention not only for minimizing NO3- contamination of groundwater but also for producing of quility of agricultural products. But still there is not Basic Standards for Organic Agriculture in Korea and Japan since they just believe organic agriculture is one kind of the environmental friendly sustainable agriculture as written in western literature. In the paper it was discussed the core skills and doctrine of IFOAM Basic Standards compare to Korean Organic Farming Method in oder to point out thed disadvantages of overuse of organic fertilizer, 50-150MT/㏊ in each cultivation, intensive monocropping in glass-house without any rotation & legume, and without any green manure. Most korean or-ganic farmer believe that the more they apply organic fertilizer, the better they pro-duce high quility of crops and they practise organic agriculture completely. It was also suggested the overuse of organic fertilizer cause the accumulation of NO3- in rhizosphere and subsequently it might lead to drinkwater pollution by nitrate leaching. In conclusion it is suggested that for successful establishment of organic agriculture, The Association of Korean Organic Agriculture, The Society of Korean Organic Agri-culture and the certification body should be developed the Basic Standards which is acceptable by IFOAM Basic Standards.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.175-183
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• 1999

Mine tailings, field soils, and paddy soils around Jingok abandoned mine were analyzed In order to investigate their pollution levels of heavy metals and cyanide. The average contents of As, Cd, Cu. Hg. Pb, Zn, and CN￣in mine tailings were 3.94$\times$$10^3$, 14.3, 266, 6.13, 4.07$\times$$10^3$, 2.51$\times$$10^3$, and 1.19mg/kg, respectively. The pollution indices calculated by the tolerance level of Kloke were 32~58 and the pH values were slightly acidic in mine tailings. In the field and paddy soils of Jingok abandoned mine area except for soils nearby mine tailings, concentrations of the heavy metals were less than standards of soil pollution of agricultural area in the environmental protection law.

• Journal of Environmental Science International
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• v.29 no.11
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• pp.1099-1108
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• 2020

In this study, the capacity of supplying agricultural water to 13 districts was analyzed by calculating the necessary water supply for the arable land of Gunwi-gun and examining the capacity of supplying water to reservoirs, streams, pumping stations, collection sites, and groundwater wells in Gunwi-gun. As a result, among the 13 districts the second district was found to be short of water by 1.2×10⁶ tons/year. In general, local governments establish drought measures by selecting drought disaster risk zones. While selecting drought-risk areas, some water-poor areas that do not have water sources should be selected, even if the entire area has a sufficient water supply. The water-supply evaluation at the regional level was insufficient for locating areas without water sources, but most areas with water sources, such as streams, reservoirs, and pumping stations, were found to have no shortage of water. To locate water shortage areas without water sources, GIS analysis conducted a field survey of areas with a distance of 4 or less than that of water sources analyzed by GIS analysis. Sixty-nine sites in 13 districts were selected for the on-site survey and six areas of water shortage were identified in areas other than the second district.