• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.4
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• pp.1-13
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• 2005

In the process of a hydrology circulation, evapotranspiration is considered a very important factor to build a plan for the development of water resources and to operate water resources system. This study purposes to estimate daily potential evapotranspiration quantity in consideration of energy factors of the surface by using spatial information such as Landsat TM (ETM+) data, DEM and Landcover. Kyounan-cheon, Han River is selected as a target area, and landcover is divided by vegetation and non-vegetation covered area. Penman-Monteith equation which considers leaf-area index is used to estimate potential evapotranspiration quantity of vegetation covered area. The combination method (energy burget and aerodynamic method) is used in non-vegetation covered area. Among the input data for estimating potential evapotranspiration, NDVI, SR and Albedo is formed by Landsat, TM and ETM+ from 1986 through 2002. ground heat flux is estimated by using NDVI distribution map, LAI distribution map is drawn by using SR distribution map. The result of estimation shows that the average potential evapotranspiration in the whole basin is about 1.8-3.2mm/day per each cell. THe results of estimating potential evapotranspiration quantity by each landcover are as follows; water surface 3.6-4.9mm/day, city 1.4-3.1mm/day, bareland 1.4-3.5mm/day, grassland 1.7-3.7mm/day, forest 1.7-3.0mm/day and farmland 1.8-3.6mm/day. The potential evapotranspiration quantity is underestimated in comparison with observed evaporation data by evaporation pan, but it is considered that it has physical propriety.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.398-406
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• 2013

Afforestation/reforestation (A/R) clean development mechanism (CDM) is the only forestry-based activities allowed under the Kyoto protocol. This study was conducted to develop a methodology to estimate greenhouse gas (GHG) removals of a small scale A/R CDM pilot project in Goseong, Gangwon Province, Korea. AR-AMS0001 was applied as a methodology and selected tree species were Pinus koraiensis, Larix kaempferi, and Betula platyphylla for total area of 75.0 ha. To improve the accuracy on the GHG removals estimation, selection of the baseline scenario and carbon pools and stratification of the project site were conducted. Based on the developed methodology, net anthropogenic GHG removals were estimated as actual net GHG removals, subtracted by baseline net greenhouse gas removals and leakage. As a result, anthropogenic GHG removals of the project were 12,415 ton $CO_2-e$ and 165.5 ton $CO_2-e/ha$. This project is the first A/R CDM in domestic site and could enhance the technical accuracy of the GHG removals estimation by using countryspecific data reflecting the site condition.

• Journal of Environmental Health Sciences
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• v.45 no.3
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• pp.238-246
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• 2019

Objective: The purpose of this study was to investigate the distribution of mineral components, health and taste index for water supply plants, spring water located in northern Gyeonggi area and bottled waters in market to analyze Ca, K, Mg Na, Si, $F^-$ and $SO_4{^{2-}}$. Method: The samples were source and tap water in 15 water supply plants over 9 river basin, 172 spring water and 20 bottled water. The Ca, K, Mg Na and Si were analyzed by ICP-OES. The $F^-$ and $SO_4{^{2-}}$ were determined by Ion Chromatograph. Then, taste and health index were calculated using Hashimoto equation. Results: The average concentration of major minerals showed in same order of Ca > Na > Mg > K for all kinds of drinking water from water supply plants, spring waters and bottled waters. Total concentration of major minerals (Ca, K, Mg, Na) was calculated that showed 26.79 mg/L of tap water, 21.81 mg/L of spring water, 32.94 mg/L of bottled water on average. So, the spring waters indicated the lowest minerals sum. The tap water from water supply plants was categorized to Group I, II for 33.3, 44.4% according to K-index and O-index. Otherwise, spring water was classified as Group I, II for 44.0, 46.3%. Conclusion: According to the results of K and O-index, water from water supply plant showed higher K-index which means good for the health. Otherwise, spring water indicated higher O-index that people can feel more delicious than tap water. Futhermore, the mineral distribution of source water from water supply plants and spring water had indicated high correlation with geological effect.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.2
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• pp.119-126
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• 2014

The object of this study was to evaluate the combined toxic interactions of the perfluorooctanoic acid (PFOA) or perfluorooctane sulfonate (PFOS) with six heavy metals (Cu, Zn, Cr, Cd, Hg, and Pb). The individual and combined toxic effects were assessed using the Vibrio fischeri assay. In case of the individual toxicity, PFOA was higher toxic than PFOS and toxicity of PFOA and PFOS were lower than heavy metal. In the toxicity of heavy metals, the $Hg^{2+}$ was found to be most toxic followed by $Pb^{2+}$, $Cr^{6+}$, $Cu^{2+}$, $Zn^{2+}$, and $Cd^{2+}$. The combined toxicity of PFOA or PFOS with $Cr^{6+}$ were synergistic effect because the $EC_{50}$ mix values were less than 1 TU. PFOA + $Zn^{2+}$, PFOS + $Zn^{2+}$, PFOA + $Cd^{2+}$ and PFOS + $Cd^{2+}$ produced addictive effect. Except in these case, all of binary mixtures show antagonistic effect. This study proved potential risk of coexistent with perfluorinated compounds and heavy metals in water environment.

• Journal of Soil and Groundwater Environment
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• v.10 no.1
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• pp.65-74
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• 2005

National groundwater monitoring stations have been managed throughout the country by Korea Water Resources Corporation (KOWACO) in order to monitor variations in quantity and quality of groundwater resources. A multi-sensor installed in each monitoring station well measures groundwater level, water temperature and electrical conductivity every six hours and the logged data are automatically transmitted to a host computer in KOWACO. Meanwhile despite regular station inspection and replacement of deteriorate or broken devices, abnormal values or outliers often occur due to intrinsic limitations of automatic monitoring and transmission. Thus prompt recognition and measures to these values are essentially required to reduce disturbance and missing period of the data. In this study, time and frequency of outlier occurrence were analyzed for the water level data obtained from national groundwater monitoring stations within the Han river basin in 2000. The analysis results indicated that the most prominent patterns of the outliers were rapid decline for water level, no variation for temperature and steep decline for electrical conductivity. This study provided a sample criterion for determining the outlier for each parameter.

• Journal of Korea Water Resources Association
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• v.39 no.5 s.166
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• pp.431-440
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• 2006

Recently, water conflicts are rapidly increasing and more serious. So, it needs to establish the reasonable water allocation rules and criteria. This study aims at performing inter-sectoral water allocation with a focus on economic effciency and social utility. To allocate water among the sectoral water uses, water shortage damage functions were estimated and then converged to the utility functions. Finally, each sectoral water uses are allocated by applying 'law equimarginal utility' to maximize social utility. Also weighting factor which reflects scale and characteristic of water demand in a region was estimated to perform the inter-regional water allocation. The water allocation rule was applied to the future water-deficit situation in Han-river basin. As a result, domestic water use was allocated more sufficient agricultural and industrial water use. Also, the water shortage occurs severely in the rural area like Gangwon-do because of its low urbanization and industrialization. This study suggests a alternative view of the economic water allocation which have difficulty under water supply mechanism in Korea.

• Particle and aerosol research
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• v.19 no.4
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• pp.111-128
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• 2023

Chungcheongnam-do has various emission sources, including large-scale facilities such as power plants, steel and petrochemical industry complexes, which can lead to the severe PM pollution. Here, we measured concentrations of PM₁₀, PM_2.5, and its metallic elements at a suburban site in Taean, Chungcheongnam-do from September 2017 to June 2022. During the measurement period, the average concentrations of PM₁₀ and PM_2.5 were 58.6 ㎍/m³ (9.6~379.0 ㎍/m³) and 35.0 ㎍/m³ (6.1~132.2 ㎍/m³), respectively. The concentration of PM₁₀ and PM_2.5 showed typical seasonal variation, with higher concentration in winter and lower concentration in summer. When high concentrations of PM_2.5 occurred, particulary in winter, the fraction of Zn and Pb components considerably increased, indicating a significant contribution of Zn and Pb to high-PM_2.5 concentration. In addition, Zn and Pb exhibited the highest correlation coefficient among all other metallic elements of PM_2.5. A backward trajectory cluster analysis and CPF model were performed to examine the origin of PM_2.5. The high concentration of PM_2.5 was primarily influenced by emissions from industrial complexes located in the northeast and northwest areas.

• Journal of Environmental Impact Assessment
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• v.8 no.1
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• pp.107-120
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• 1999

This study was performed to survey the general feature of reservoir sediment in Daecheong, Sapkyo and Kumkang reservoir. For investigations, sediments were sampled at four sites in Dae-Cheong and two sites in SapKyo and Kumkang in June and October. The items for investigation are as follows; water content, loss on ignition(IG), porosity of sediment, contents of element such as hydrogen, nitrogen, carbon, phosphorus contents and nutrient release rates. Loss on ignition was measured to determine the contents of organic substance. And its ranges were determined 2.4~16.2% in Daecheong reservoir, 5.6~27.9% in Sapkyo and 4.8~18.7% in Kumkang reservoir. And, total phosphorus contents in sediments were measured $677{\sim}5,238{\mu}g/g$ in Daecheong, $780{\sim}1,417{\mu}g/g$ in Sapkyo and $604{\sim}1,452{\mu}g/g$ in Kumkang reservoir. And release rates of nutrients were calculated $0.05{\sim}8.63mgP/m^2day$ and $4.99{\sim}36.56mgN/m^2day$ in Daecheong, $1.83{\times}10^{-3}{\sim}3.23{\times}10^{-2}mgP/m^2day$ and $1.97{\sim}.22mgN/m^2day$ in Sapkyo, $8.31{\times}10^{-3}{\sim}6.51{\times}10^{-2}mgP/m^2day$ and $0.89{\sim}4.42mgN/m^2day$ in Kumkang reservoir, respectively. And this study attempted to determine the humus level of sediments. As a result of elemental analysis, C/N ratio was determined 3.0~13.1 in Daecheong reservoir, 6.5~13.0 in Sapkyo and 3.6~12.6 in Kumkang reservoir, respectively. From the elemental analysis, humus levels of reservoirs were changed from mesohumic to oligohumic state in all reservoirs.

• Korean Journal of Plant Taxonomy
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• v.46 no.4
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• pp.413-419
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• 2016

Two unrecorded naturalized species, Stachys agraria Schltdl. & Cham. and Dracocephalum moldavica L (Lamiaceae), are newly reported in Korea. Stachys agraria and D. moldavica were found at Seogwipo-si on Jeju-do and at ChunChen-si in Gangwondo in Korea, respectively. Stachys agraria is distinguished from other related Korean taxa by corolla of 2.4-5.2 mm long with six to twelve flowers in the node. Its local name is "Ae-gi-seok-jam-pul" based on shorter than longer corollar. Dracocephalum moldavica was distinguishable from other Dracocephalum in Korea by the following combination of characters, oblong to ovate-triangular ($1.7-2.4cm{\times}0.8-1.2cm$) leaves and rough crenate at the margin. This taxon is referred to as 'Hyang-yong-meo-ri' in Korean based on its fragrance. We provide a description, illustrations, photographs, and a key of related taxa in Korea.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.608-608
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• 2012

현재 기후변화의 기상변동성이 커짐에 따라 태풍 및 집중호우 등의 이상기후 현상이 전 지구상에 걸쳐 광역적으로 나타나고 있다. IPCC에서는 이러한 기후변화가 기온 상승에 따른 증발산량의 증가, 강수량 및 유출량의 시공간적 분포의 변동 등을 초래하여 수자원의 효율적 관리 및 안정적인 공급에 어려움을 증대시킬 것으로 전망하였다. 뿐만 아니라 현재 국내 전반에 걸쳐 4대강 사업이 진행되고 있고, 낙동강에서도 낙동강 살리기 사업이 실시되어 주변 지형들의 변화가 진행되고 있다. 이러한 지형의 변화는 현재까지 구축되어 있는 기존자료의 대폭적인 변화를 의미하므로 홍수관련 연구결과에도 변화를 의미하고 있다. 이에 따라 4대강 사업 이후의 기후 변화에 따른 낙동강유역에서의 유출량의 증가를 분석하여 극한홍수의 발생가능성을 제시하고 이러한 극한홍수발생에 따른 위험지역도 과거에 의해 변경될 것으로 판단되어 국내외적으로 하천의 수리검토에 널리 사용되고 있는 1차원 수리해석 프로그램인 FLDWAV를 이용하여 취약지점을 분석하고 위험도를 분석하고자 한다. 낙동강 살리기 사업으로 낙동강에 건설된 8개의 보를 고려한 본류 및 지류에서의 제내지 및 제외지 지형데이터를 구축하고 구축된 자료을 이용해 낙동강 본류 및 지류에 대해서 극한홍수시 200년 빈도, 500년 빈도 홍수량 및 홍수위를 FLDWAV를 통해 정상류로 계산해서 예측하고 500년 빈도 홍수량과 홍수위를 부정류로 계산하여 제방고와 홍수위를 비교하여 범람위험지역을 선정하였다. 그리고 그 결과를 통해 GIS를 통하여 범람위험지역 제내지의 주요도심 구간 포함, 범람 범위를 분석함과 동시에 극한홍수에 따른 도심구간, 비도시구간 등의 범람범위를 분석하였다. 또한 선정한 범람위험지역의 범람 피해규모를 산정하고 피해범위의 현황을 파악하였다. 연구의 결과는 다음과 같이 나타났다. 500년 빈도 홍수시 범람위험지역은 낙동강 본류의 하류부에서 각각 154.7km, 123.2km, 12.9km에 위치한 지점이 선정되었으며 각 지점의 피해규모는 제내지에 범람된 유출량의 수위는 각각 21.7m, 24.3m, 2.11m로 계산되었고 이때의 피해면적은 각각 $2.68km^2$, $2.64km^2$, $1.25km^2$로 나타났다. 이 결과는 기후변화로 인한 극한홍수 발생 가능성과 취약지점의 분석을 통한 지역의 홍수피해 저감과 정책개발에 기본 자료로 활용될 것이며 낙동강 살리기 사업으로 인한 하천주변 지형의 변화를 제공함으로서 앞으로 진행될 연구의 기본 자료로서 이용가능 할 것으로 판단된다. 또한 이전의 홍수방어계획을 개선한 새로운 홍수방어계획의 수립을 통하여 향후 발생될 홍수의 예방 및 대응방안 수립의 참고자료로 이용될 것이며 제내지 및 제외지의 공간확보 연구를 통해 해당 지자체의 토지매수계획의 참고자료로 이용 가능할 것으로 기대된다.