• 해양환경안전학회지
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• 제29권4호
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• pp.332-337
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• 2023

우리나라는 3면이 바다로 둘러싸여 있을 뿐만 아니라 국가하천과 지방하천의 연장이 26,843km에 달하고 있어 풍부한 해수면과 내수면이 함께 공존하는 지리적 특징이 있다. 국민소득의 향상 등으로 내수면에서 운항하는 선박이 지속적으로 증가하고 있어 내수면에서 선박사고 및 인명사고의 위험성도 증가하고 있다. 본 연구에서는 내수면관련 법령조사 및 운영현황 분석을 통하여 거시적인 내수면 선박의 안전관리 대책 방안을 제시하였다. 그 개선방안으로 하드웨어적 인프라로서 사고 초기대응 및 인명구조의 골든타임 확보를 위한 충분한 내수면 소방정의 확보와 내수면 선박 사고예방 전문기관의 운영을 제언하며, 소프트웨어적 인프라로서 내수면 선박의 출항통제기준 마련과 현행 해수면 선박에만 적용하고 있는 안전진단제도를 기반으로 내수면 선박의 특성에 맞는 맞춤형 제도도입을 제언하였다. 이러한 내수면 안전관리 정책은 내수면 선박 사고발생 시 신속하고 체계적인 대처 방안 마련에 기여할 것으로 기대되며, 세월호 사건 이후 잠시 활성화 되었던 내수면 선박에 대한 안전관련 연구에 지속적인 관심을 갖는 기회가 되었으면 한다.

• 한국물환경학회지
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• 제32권6호
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• pp.520-527
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• 2016

Phycocyanin (PC) is one of the water-soluble accessory pigments of cyanobacteria species, and its concentration is used to estimate the presence and relative abundance of cyanobacteria. In laboratory experiments, PC content of field data were determined using Sarada's freeze-thaw method in algal bloom season. The effectiveness of three selected extraction methods (repeated freeze-thaw method, homogenization, power control) for PC were determined. The extraction efficiency of phycocyanin was the highest (of the methods compared) when a single freezing-thawing cycle was followed by pre-sonication. Applying this optimized method to surface water of Korean inland waters, the average concentration distribution was estimated at $2.9{\sim}51.9mg/m^3$. It has been shown that the optimized pre-sonication method is suitable to measure cyanobacteria PC content for the characterization of inland waters. The approach and results of this study indicates the potential of effective methods for remote monitoring and management of water quality in turbid inland waters using hyperspectral remote sensing.

• 한국환경보건학회지
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• 제3권1호
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• pp.9-12
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• 1976

A study was performed to find out the fluoride contents in surface and ground waters from June, 1973 to July, 1974. Water samples were collected from 53 surface and ground water sources. The results are as follows: 1. Out of 53 samples, the ground water of Hwaengsung had the highest fluoride contents (1.6 mg/l) and 13 samples did not. have fluoride at all. 2. The waters from Yoju (ground), Chongnung (ground) Hwaengsung (ground) and Namyang (ground) had optimum fluoride level (0.6~1.7mg/l) for the prevention of dental caries. 3. The ground waters had more fluoride contents than surface waters and the waters of coastal areas had less fluoride contents than those of inland. 4. The waters of Kangwon province had the most fluoride contents (mean 0.57mg/l) and the waters of Cheju do had the least fluoride contents (mean 0.06 mg/l)

• Fisheries and Aquatic Sciences
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• 제27권4호
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• pp.240-255
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• 2024

Widas Reservoir is situated in an area of 570 ha in the Pajaran Village, Madiun Regency, East Java Province, Indonesia, playing an essential role in fisheries, with the average fish catch per year of about 283 tons/year. This study explores the standing stock, growth parameters, mortality, and exploitation rates of several dominant fishes in Widas Reservoir. This study was carried out from February to November 2019. Fish stocks were estimated using acoustic tools, fish catch records, and sizes collected by local enumerators. Fish length frequency sampling was conducted on several dominant fish species, such as Oreochromis niloticus, Barbonymus gonionotus, and Osteochilus vittatus. Based on the length-frequency data, estimating fish population dynamics, the fish population dynamics (infinitive length (L_∞) and growth coefficient (K)) estimation was run in a time series using the Fish Sock Analysis Tool, II (FISAT II) program package. Moreover, the estimation of natural mortality parameters, the fishing mortality parameter, and the exploitation rate was also performed. The approximated overall fish stock in the Widas Reservoir was about 79,848 kg, which lowered with the increase in water depth. Of particular concern, in the surface layer at a depth between 1-5 m, the fish stock reached 58,813 kg, while in the deeper zone (> 15 m), the value significantly lowered by about 98%, reaching 1,219 kg. These results indicate an overfishing in the Widas Reservoir. The value of the exploitation rate (E) of B. gonionotus was 0.748, O. niloticus 0.8, and O. vittatus 0.7, respectively, proving the overfishing states occurred in the study area. Therefore, regulations governing the number of catches and the use of fishing gear are crucial in Widas Reservoir, particularly the use of lift and gill nets with a mesh size of less than 2 cm.

• 한국지역지리학회지
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• 제19권2호
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• pp.352-361
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• 2013

기상 현상을 예측하는 수치예보모델의 주요한 기초 입력 데이터로 토지이용, 지형, 식생, 지표 온도 등이 있다. 이 중 지표 온도의 일부인 내륙 수면 온도에 대한 지상 관측 데이터는 강이나 호수의 일부 지역에만 존재한다. 따라서 본 연구는 수치예보모델의 입력 데이터인 내륙 수면 온도로 활용할 수 있는 MODIS 위성영상의 지표 온도 데이터의 오차정도를 확인하기 위해 국내 내륙 수온 지상 관측 데이터와 비교 분석하였다. 이를 위해 2011년 7월부터 2012년 6월까지 약 1년의 MODIS Land Surface Temperature(LST) 데이터와 수질자동측정망의 수온 데이터를 비교하였다. MODIS 데이터는 주간 및 야간 데이터로 구성되는 데, 각각의 월 평균 오차는 $2^{\circ}{\sim}8^{\circ}C$, $3^{\circ}{\sim}12^{\circ}C$로 주간 데이터의 오차가 작았다. 특히, 주간 데이터의 오차는 가을에 $2^{\circ}C$로 다른 계절에 비해 작았고, 야간 데이터는 여름에 $3^{\circ}C$로 다른 계절에 비해 작았다. 또한 지역적으로는 한강, 낙동강, 금강, 영산강의 4대강을 비교한 결과 가장 남쪽에 있는 영산강 유역에서 가장 오차가 작았다. 본 연구를 통해 수치예보모델의 입력 데이터로 활용함에 있어 MODIS 지표 온도 데이터의 오차 정도를 확인할 수 있었다. 연구 결과는 아시아 지역에 대해 수치예보모델을 운용할 때 북한 및 해외 지역에 대해 MODIS 지표 온도 데이터를 활용함에 있어 그 오차 정도의 기준이 될 수 있을 것이다.

• 환경영향평가
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• 제20권2호
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• pp.199-205
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• 2011

The Saemangeum embankment construction have changed the flowing on the topography of the coastal marine environment. However, the variety of ecological factors are changing from outside of Saemangeum embankment area. The ecosystem of various marine organisms have led to changes by sea surface temperature. The aim of this study is to monitoring of sea surface temperature(SST) changes were measured by using thermal infrared satellite imagery, MODIS and Landsat. The MODIS data have the high temporal resolution and Landsat satellite data with high spatial resolution was used for time series monitoring. The extracted informations from sea surface temperature changes were compared with the dyke to allow them inside and outside of Saemangeum embankment. The spatial extent of the spread of sea water were analyzed by SST using MODIS and Landsat thermal channel data. The difference of sea surface temperature between inland and offshore waters of Saemangeum embankment have changed by seasonal flow and residence time of sea water in dyke.

• Ocean and Polar Research
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• 제39권1호
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• pp.35-43
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• 2017

Concentrations of dissolved organic carbon (DOC), dissolved organic nitrogen (DON), dissolved organic phosphate (DOP), and colored dissolved organic matter (CDOM) were measured in the coastal sea off inland aqua farms in northeastern Jeju Island in summer 2015. The highest concentrations of DOC, DON, and DOP were revealed in the surface water off Hado-ri where the lowest salinity conditions prevailed (31.6). The concentrations of DOC, DON, and DOP in the surface water were lower in the inner stations (SH1-1, 1-2, and 1-3) near the aqua farms of the Haengwon-ri than in the outer stations. The concentrations of DOC, DON, and DOP negatively correlated with salinity. These results indicate that the contribution of dissolved organic matter (DOM) from the aqua farms seems to be not significant. On the other hand, the higher concentrations of DON and DOP in the inner stations of Hado-ri (HD 1-1) seem to be attributed to excrement of migrating birds. The three components of CDOM (T, M, and C peaks) showed no relationship with salinity, perhaps due to various in situ productions by marine organisms and decomposition by ultraviolet radiation. The observed lower C:M ratio, an indicator of terrestrial source, and the higher biological index (BIX) of CDOM in the station off Hado-ri indicate that DOM is produced mainly by biological activity. Based on the higher humification index (HIX) of CDOM and the higher DOC:DON ratio off Haengwon-ri, refractory DOM in the inland aqua farms is likely transported to the coastal sea.

• 한국토양비료학회지
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• 제44권6호
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• pp.1314-1319
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• 2011

This study was carried out to investigate the surface soil organic carbon fractions affecting by different land use types, including needle-leaf forest (FN), broad-leaf forest (FB), pasture, annual upland cropping land (upland), and paddy rice land (paddy). We chose seven regions across Korean inland, considering sea level altitude, and measured soil organic carbon content and physico-chemical properties such as bulk density at a depth of 0~15 cm using core samples in April for the each land use type. In addition, labile organic carbon fractions in soil including light fraction and hot water extractable carbon were investigated. From this study, organic carbon storage (Mg C per ha) in the upper 15-cm soils was highest in FB (37.8), and decreased in the order of pasture (29.1), FN (28.8), paddy (21.9), and upland crop (19.9). In forest, more than 20% of soil organic carbon existed as light fraction, the free organic matter. Hot-water extractable carbon contents of soils in five land use types were lower than 7% of their soil organic carbon content.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1199-1204
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• 2005

The purpose of field monitoring system in KHC-Test Road located at Joongbu-Inland Highway, is to provide the performance data for traffic and environmental loadings from pavement surface. Among them, water content reflectometers(WCR) are used to measure the volumetric water content of subgrades soils used in test roads. However, most of the WCRs are not well-calibrated based on the field conditions. In this study, the laboratory based test is performed at various density conditions to evaluate the volumetric water content in subgrade Soils with a WCR. Based on the laboratory testings, the effect of density on WCR measurement are well evaluated for predicting the volumeric water content.of subgrades soils in KHC-Test road.

• 생태와환경
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• 제54권4호
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• pp.384-389
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• 2021

본 연구는 2020년 10월 23일에 경기도 가평군 설악면에 위치한 청평호에서 수행되었으며, 어군탐지기를 이용해 획득한 자료를 기반으로 어류의 수평 및 수직 분포 패턴을 분석하였다. 어군탐지 조사가 수행된 구간의 총 수면적은 782,853 m²였으며, 수심(water depth, WD)이 10~12 m인 구간이 전체 수면적의 31.7%로 가장 넓게 분포하는 것으로 나타났다. 다양한 WD 구간별로 어류의 개체 밀도 산출 결과, 4~6 m 구간에서 0.98 개체/100 m²로 가장 높게 나타나, 수면적 대비 가장 많은 어류가 분포하는 것으로 확인되었다. Heat map 분석 결과 청평호 구간에서는 가평대교의 우안측에서 어류의 밀도가 가장 높게 나타났으며, 이러한 수평 분포 특성에서 특별한 경향성은 확인할 수 없었다. 어류의 수직분포 분석 결과, 어류가 관측된 수심(Fish depth, FD)이 6 m 이하인 경우가 전체 관측 대비 86.6%로 나타났다. 수심 대비 어류의 관측 수심(Relative height, RH) 분석 결과, 수심이 깊어질수록 어류가 상대적으로 표층에 분포하는 경향성을 확인할 수 있었다. 이와 관련해서는 수체의 수심별 수온 차이 등 다양한 원인이 있을 것으로 예상되며 추가적인 연구가 필요하다.