• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.188-188
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• 2016

The Mekong which is one of the world's most significant rivers plays an extremely important role to South East Asia. Lying across six riparian countries including China, Myanmar, Thailand, Laos, Cambodia and Vietnam and being a greatly biological and ecological diversity of fishes, the river supports a huge population who living along Mekong Basin River. Therefore, much attention has been focused on the giant Mekong Basin River, particularly, the soil erosion and sedimentation problems which rise critical impacts on irrigation, agriculture, navigation, fisheries and aquatic ecosystem. In fact, there have been many methods to calculate these problems; however, in the case of Mekong, the available data have significant limitations because of large area (about 795 00 km2) and a failure by management agencies to analyze and publish of developing countries in Mekong Basin River. As a result, the Universal Soil Loss Equation (USLE) model in a GIS (Geographic Information System) framework was applied in this study. The USLE factors contain the rainfall erosivity, soil erodibility, slope length, steepness, crop management and conservation practices which are represented by raster layers in GIS environment. In the final step, these factors were multiplied together to estimate the soil erosion rate in the study area by using spatial analyst tool in the ArcGIS 10.2 software. The spatial distribution of soil loss result will be used to support river basin management to find the subtainable management practices by showing the position and amount of soil erosion and sediment load in the dangerous areas during the selected 56- year period from 1952 to 2007.

• 한국토양비료학회지
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• 제44권6호
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• pp.1112-1117
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• 2011

재배기간이 긴 잎들깨 시설 촉성재배 조건에서 질소시비 수준별 시험을 통하여 토양의 질산태질소 함량에 따른 질소 웃거름시비량 결정기준을 설정하였다. 잎들깨 주산단지인 금산과 밀양 두 지역에서 각각 1개의 시설하우스에서 질소시비량 5수준과 관행구를 난괴법 3반복과 4반복으로 각각 실시하였다. 생육시기별로 매달 건물중과 질소흡수량, 마디생장량을 조사하였고, 토양질산태질소를 분석하였다. 금산포장의 마디당 질소 요구량은 $2.2kg\;10a^{-1}$, 밀양포장은 $3.5kg\;10a^{-1}$로 조사되었다. 토양질산태질소의 하한기준은 금산포장과 밀양포장 모두 $NO_3$-N $10mg\;kg^{-1}$로 설정하였다. 상한기준 설정은 토심 15 cm, 용적밀도 $1.2Mg\;m^{-3}$, 토양 중 질산태질소의 이용율 70%를 적용하여 잎들깨 1마디에 필요한 질소요구량을 충족하는 수준으로 결정하여 금산포장과 밀양포장 각각 $30mg\;kg^{-1}$과 $40mg\;kg^{-1}$로 설정하였다. 따라서 금산지역은 Y=-0.157X + 4.71에 의해, 밀양지역은 식 Y=-0.1667X + 6.6667에 의해 잎들깨 1마디 생육에 필요한 질소 웃거름 시비량을 결정할 수 있었다.

• 한국농공학회논문집
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• 제48권6호
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• pp.101-112
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• 2006

A Geographic Information System (GIS) was developed to estimate basin-wide soil losses using the Universal Soil Loss Equation (USLE). It was applied to estimate the annual average soil losses from the Saemangeum watershed. The USLE factors for each subarea of uniform land use and treatments were estimated from the GIS routines from digital topographic maps, land cover and detailed soil maps. A routine was developed to estimate the averaged cropping management factors (C) of USLE for multi-cropping farmlands, based on cropping system records from the district offices. The resulting C factors ranged from 0.28 to 0.35 for multi-cropping areas. The estimated annual average soil loss was approximately 2.9 million tonnes. Typical soil losses from different land uses were 0.8 t/ha at paddies, 33.7 t/ha at uplands and 1.1 t/ha from forested mountains. It was also found that 6.0% of the arable land of the watershed possessed high risks of soil losses, and conservation measures were needed to reduce soil losses.

• International Journal of Computer Science & Network Security
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• 제23권4호
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• pp.146-150
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• 2023

In areas where water is scarce, water management is critical. This has an impact on agriculture, as a significant amount of water is used for that purpose. Electronic measurement equipment are essential for regulating and storing soil data. As a result, research has been conducted to manage water usage in the irrigation process. Many equipment for managing soil fertility systems are extremely expensive, making this type of system unaffordable for small farmers. These soil fertility control systems are simple to implement because to recent improvements in IoT technology. The goal of this project is to develop a new methodology for smart irrigation systems. The parameters required to maintain water amount and quality, soil properties, and weather conditions are determined by this IoT-based Smart irrigation System. The system also assists in sending warning signals to the consumer when an error occurs in determining the percentage of moisture in the soil specified for the crop, as well as an alert message when the fertility of the soil changes, since many workers, particularly in big projects, find it extremely difficult to check the soil on a daily basis and operate agricultural devices such as sprinkler and soil fertilizing devices.

• Journal of Ginseng Research
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• 제40권1호
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• pp.28-37
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• 2016

Background: Panax ginseng cannot be cultivated on the same land consecutively for an extended period, and the underlying mechanism regarding microorganisms is still being explored. Methods: Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) and BIO-LOG methods were used to evaluate the microbial genetic and functional diversity associated with the P. ginseng rhizosphere soil in various cultivation ages and modes. Results: The analysis of microbial diversity using PCR-DGGE showed that microbial communities were significantly variable in composition, of which six bacterial phyla and seven fungal classes were detected in P. ginseng soil. Among them, Proteobacteria and Hypocreales dominated. Fusarium oxysporum, a soilborne pathogen, was found in all P. ginseng soil samples except R0. The results from functional diversity suggested that the microbial metabolic diversity of fallow soil abandoned in 2003was the maximum and transplanted soil was higher than direct-seeding soil and the forest soil uncultivated P. ginseng, whereas the increase in cultivation ages in the same mode led to decreases in microbial diversity in P. ginseng soil. Carbohydrates, amino acids, and polymers were the main carbon sources utilized. Furthermore, the microbial diversity index and multivariate comparisons indicated that the augmentation of P. ginseng cultivation ages resulted in decreased bacterial diversity and increased fungal diversity, whereas microbial diversity was improved strikingly in transplanted soil and fallow soil abandoned for at least one decade. Conclusion: The key factors for discontinuous P. ginseng cultivation were the lack of balance in rhizosphere microbial communities and the outbreak of soilborne diseases caused by the accumulation of its root exudates.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.346-346
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• 2017

In Northern Laos, maize is cultivated in continuous cropping without fertilizer, fallowing nor any other soil conservation practice. It is expected that this inadequate management in maize cultivation will degrade soil and decrease yield. However, there is limited information about the change of soil condition and yield under continuous maize cultivation. We tried to evaluate the change of soil condition and yield under continuous maize cultivation in Northern Laos. Our study was conducted in farmer's flat and slope fields in Sainyabuli province where maize cultivation had been introduced earlier than the other provinces of Northern Laos. Our study was conducted in 21 fields in 2014, and in 19 fields in 2015. We analyzed grain yield and soil characteristic (total carbon (TC), total nitrogen (TN), available phosphorus (Av-P), exchangeable cation, pH, soil texture) at 3 places in each field. The 3 places were set at different elevation level (lower position, middle position, upper position) in slope fields. Further, the period of continuous maize cultivation and crop management practice were investigated. Then, by evaluating the relation between the period of continuous maize cultivation and yield and the soil characteristics, the effect of maize cultivation was estimated. Crop management practices were similar among the investigated fields. Maize was cultivated in rain season. Grain seed and cob were harvested on September or October, but shoot was left on the fields. No crop was cultivated during dry season. Fertilization and fallowing has never been conducted under continuous maize cultivation. On the other hand, the period of maize cultivation was different among the fields, and ranged from 2 years to 30 years. In the slope fields, as the period of continuous maize cultivation was longer, the contents of TC and TN were lower at all 3 positions, Av-P content was lower at the upper position, exchangeable potassium (Ex-K) content was lower at the middle and the upper positions. The other soil characteristics weren't related with the period of maize cultivation in the slope fields. In contrast, soil characteristics weren't related with the period of maize cultivation in the flat fields. Yield was lower as the period of maize cultivation was longer at the upper position of the slope fields. At middle position of slope fields, yield tended to be low with increase of the period of maize cultivation. In contrast, yield wasn't related with the period of continuous maize cultivation in flat fields. From the results about crop management, it was presumed that the period of maize cultivation was one of the main factors causing the difference of yield and soil characteristics among the fields. Therefore, from the result of yield and soil condition, it was considered that the continuous maize cultivation decreased soil productivity in the slope fields with decline of TC, TN, Av-P, Ex-K and yield at upper position of slope fields, and decline of TC and TN in the other positions in Sainyabuli province.

• 한국작물학회지
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• 제62권2호
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• pp.134-142
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• 2017

Crop production in rice paddy fields is of great importance because of declining rice consumption and the low self-sufficiency ratio for field crops in Korea. A controlled drainage system (CDS) is recognized as an effective means to adjust water table (WT) levels as needed and control soil water content to improve the soil environment for optimum crop growth. The present study evaluated the effects of a CDS on soil characteristics, including soil water distribution and soybean development in paddy fields. The CDS was installed with two drain spacing (3 m and 6 m) at the experimental paddy field at the National Institute of Crop Science, Miryang, Korea. It was managed with two WT levels (0.3 m and 0.6 m) during the growing season. Soil water content, electrical conductivity and plant available nitrogen content in the soil were significantly greater in the 0.3 m WT management plots than in the 0.6 m plot and the control. At the vegetative stage, chlorophyll content was significantly lower with higher WT control because of excess soil moisture, but it recovered after the flowering stage. Soybean yield increased with WT management and the 0.6 m WT treatment produced the greatest grain yield, $3.38ton\;ha^{-1}$, which was 50% greater than that of the control. The CDS directly influenced outflow through the drains, which significantly delayed nutrient loss. The results of this study indicated that WT management by CDS can influence soil characteristics and it is an important practice for high yielding soybean production in paddy fields, which should be considered the crop growth stages for stable crop production.

• 공업화학
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• 제23권6호
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• pp.618-623
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• 2012

석유의 누출로 인해 토양과 지하수 오염이 점차 증가되면서, 토양환경에 대한 중요성이 점차 늘고 있다. 토양오염은 다른 환경오염에 비해 정화비용이 비싸며, 긴 정화기간이 요구된다. 본 연구에서는 토양오염을 발생시킬 수 있는 대표적 석유제품에 대한 물성분석과 함께 토양에 누유시킨 뒤, 석유계 총탄화수소화합물의 스펙트럼 패턴을 분석함으로써 유종들의 특성을 분석하였다. 이는 추후 석유에 의한 토양오염 발생 시, 어떤 석유제품에 의한 오염인지 쉽게 판단이 가능할 것이다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권4호
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• pp.27-35
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• 2012

Recently, there has been increasing interest in the use of rain garden systems as environmentally friendly ecological infrastructures for controlling stormwater runoff and managing non-point source pollution and information for the contamination of soil and plants can be essential for sustainable rain garden management. In this study, four rain garden mesocosms, namely single species planting with Rhododendron lateritium, single species planting with Zoysia japonica, mixed planting with R. lateritium and Z. japonica, and control without plants, were tested to investigate the change in concentrations of nutrients (N and P) and heavy metals (Cd, Cu, Pb, and Ni) in the soil and plants used in the rain garden system. The presence of plants resulted in greater nutrient retention in soil and lower potential leaching from the system. All systems showed an increase in the heavy metal concentrations in soil. The concentrations of most heavy metals were found to be higher in the herbaceous plants (Z. japonica) than in the shrubs (R. lateritium). The belowground part (root) had higher heavy metal concentrations than the aboveground part (leaf) but also showed a potential increase in leaves, and hence, careful plant management should be considered during rain garden operation.

• 한국토양비료학회지
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• 제46권6호
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• pp.482-486
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• 2013

Assessment of nutrient balance in region unit is important to make a decision on nutrient management in agriculture. In this study, the nutrient demand in arable land and nutrient supply from livestock manure and chemical fertilizer were estimated from pig-concentrated areas. Three regions (H, I and J) were selected on the basis of pig numbers per unit area of arable land. In H and I regions, nitrogen amount from pig manure occupied about 50% of total livestock manure. Nutrient supply was three times higher compared to the nutrient demand in each of 3 regions. Soil available phosphate of higher pig-populated area in regional unit was higher than less populated livestock area. Therefore, livestock manure-derived regional management and monitoring of soil nutrient contents is necessary for the minimization and improvement of nutrient surplus.