• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.396-397
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• 2000

게류는 절지동물문 갑각목 십각아목에 속하는 무척추동물로서 해양동식물의 사체나 데트리터스를 먹으며 해양생태계의 먹이그물에서 중요한 생태적 지위를 갖는다. 조간대에 서식하는 종은 육상과 조하대 사이, 하구역에 서식하는 종은 담수와 해수사이, 심해에 서식하는 종은 표층과 심층 사이의 물질과 에너지 순환을 제공한다. 국내에서 이루어진 게류에 관한 연구는 주로 일부 상업성 종류의 자원학적 연구만 이루어져 있고, 군집에 관한 연구는 광양만 잘피밭에 서식하는 게류 군집의 종조성과 계절 변동 (Huh and An, 1998)이 있을 뿐 아직까지 우리나라 해역에 어떤 종이 언제 출현하는지 조차 잘 알려져 있지 않다. 본 연구에서는 가덕도 주변 해역에 서식하는 게류 군집의 종조성과 계절변동을 파악하고자 하였다. (중략)

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1116-1120
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• 2008

댐은 사회경제적으로 다양한 편익을 제공하고 있지만, 댐을 철거하자는 많은 NGO와 다른 환경단체들이 주장하는 생태비용의 이유로 최근에 재평가를 시행하고 있다. 댐 건설로 인한 유사의 차단과 첨두 홍수량의 감소는 하천의 장갑화와 유사의 하구이송을 감소시켜 댐 직하류 하천에 영향을 미치고 있다. 이러한 직 간접적인 영향들은 하도 내에 물리적 서식처 형상, 생태학적 연관성, 이로 인해 하천지형학에서의 변화를 초래하게 된다. 댐 운영이 하류의 하도 및 생태계에 미치는 영향 정도를 정량화하는데 있어 기존의 단순한 유황 분석을 통한 갈수량, 저수량, 평수량, 풍수량은 댐으로 인한 하류 하천의 영향을 정량적으로 분석하는 데는 한계가 있다. 따라서 본 연구에서는 다양한 수문변화를 정량적으로 계산할 수 있는 IHA(Indicators of Hydrologic Alteration) 모형을 이용하여 합천댐 직하류 하천의 수문변화 특성을 분석하였다. 댐의 유입량과 방류량을 비교한 결과, 대체적으로 홍수기(6월$\sim$9월)에는 댐에 의한 유량 조절효과로 첨두량이 감소하였으며, 그 이외의 월 평균유량은 증가하여 유황이 개선되는 경향을 나타났으며, 수문변화율은 댐의 방류량이 유입량보다 작게 나타났다. 본 연구에서 산정된 수문특성 변화 지표는 댐 유역의 치수, 이수, 환경생태적인 변화를 종합적으로 이해하고 적응하는데 있어, 댐 운영을 최적화하거난 효과적으로 이용될 수 있을 것으로 판단된다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.76-86
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• 2012

Macrozoobenthos were collected from 24 sites using small grab ($0.05m^2$) in order to see the spatial distribution of them at Sueocheon stream at the northern part of Gwangyang Bay during summer season when the maximum ecological processes are occurring. A total of 44 species of macrozoobenthos occurred, and their mean density was $789individuals/m^2$. Mollusks was the dominant faunal group accounted for 43.1% and 86.8% of the whole community density and biomass, respectively. Top five dominant species were a molluscan, Corbicula japonica (40.7%), two polychaete worms, Neanthes japonica (19.3%) and Heteromastus filiformis( 8.1%), and two crustaceans, Paranthura japonica (6.9%) and Jaeropsis sp. (6.9%). Species diversity index was very low with mean value of 1.12 and maximum value was recorded at the river mouth. At the upper stream, a brackish water species such as Corbicula japonica showed their maximum population density. The overall distribution of stream macrobenthos showed a rather simple pattern along with salinity and grain size gradients with few brackish water species occurring at coarse sediments in the stream but more diverse faunas inhabiting fine sediments in the river mouth.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.1
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• pp.9-16
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• 2010

The purpose of this study is to clarify the origin of organic matters on sediment and the characteristics of seasonal variation at an estuarine tidal flat. Silt-clay content (<63 ${\mu}m$), chlorophyll a, TOC, C/N ratio and the stable isotope ratio of carbon and nitrogen were measured at tidal flat around the estuary of the Nanakita River. As a result, organic matters originating from marine organic matter and bethic microalgae greatly contributed to sedimentation of organic matters at Stn.A, sandy tidal flat, though terrigenous organic matters did at Stn.C, muddy tidal flat. Furthermore, it was revealed that the volume and origin of organic matters in the sediments depended on seasonal variation, and the factors were different from the Stns, i.e. bentic microalgae and event for Stn.A, and the eventual sedimentation of organic matters originating from terrestrial plants, respectively.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.303-315
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• 2012

This study developed a wetland inventory describing the characteristics and change of Nakdong estuary wetland ecosystem. The data which are used to develop the inventory are Landsat TM(April 1, 1986; June 23, 1987; June 18, 1997), Kompsat(Jan. 12, 2008) and LiDAR(March 1, 2009) images and published monitoring data of Busan metropolitan city. The developed inventory was utilized for the classification of wetland cover, the spatiotemporal analysis of wetland and landscape pattern, the distribution of benthos species etc. Furthermore, the developed 3 dimensional wetland map showed a better way to delineate wetland boundary and understand wetland dynamics. Considering these results, it's concluded that it is possible to use the similar techniques for the development of wetland inventory in Korea.

• Korean Journal of Ecology and Environment
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• v.55 no.2
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• pp.132-144
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• 2022

The fish community in the Seomjin River-Seomjin River Estuary-Gwangyang Bay coast continuum was investigated three times from March 2019 to October 2019. The collected species at the eight sites during the survey period were 49 species belonging to 31 families, including two endangered species. According to Bray-Curtis similarities, observations were divided into four groups based on the fish community composition; two groups (group 1, 2) and two uncategorized groups (group 3, 4). ANOSIM based on spatial and temporal groupings indicated that the spatial differences in fish communities (R=0.398, P=0.001) were relatively more important than the temporal differences (analysis of similarities, R=0.273, P=0.002). In particular, there were significant differences between groups 1 and 2 (analysis of similarities, R=0.556, P=0.001), and similarity percentage analysis revealed that Argyrosomus argentatus (9.4%), Favonigobius gymnauchen (6.9%) and Konosirus punctatus (5.9%) contributed to these differences of fish assemblages for each group. The fish fauna distributed in the Seomjin River-Gwangyang Bay ecosystem were spatially divided and the number of species and number of individuals showed seasonal differences. This study could be a basis for understanding changes in the fish community and implementing conservation and management strategies on major species within a continuous environment of the river-estuary-ocean continuum.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.28 no.4
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• pp.158-177
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• 2023

An estuary is a transitional water area that links the land and sea through rivers and streams, transporting various components from the land to the sea, which plays an important role in determining primary productivity in the coastal environment, and this coastal ecosystem captures a huge amount of carbon into biomass, known as blue carbon, which mitigates climate change as a potential carbon reservoir. This study examined the variation of mean grain size and organic carbon content of the surface sediments for 6 years and analyzed their relationship in the western and southern estuarine areas (Han River Estuary, Geum River Estuary, Yeongsan River Estuary, Seomjin River Estuary, and Nakdong River Estuary) and the East Sea upwelling area. During the sampling period (2015 to 2020), seasonal variation of both properties was not observed, because their variations might be controlled by diverse oceanographic environments and hydrographic conditions within each survey area. However, despite the synoptic problem of all samples, the positive relationship was obtained between the averages of mean grain size and organic carbon content, which clearly distinguishes each survey area. The unique positive relationship in all estuarine areas implies that the same process by sediment clay particles is important in the organic carbon accumulation. However, additional important factor may be expected in the organic carbon accumulation in the East Sea upwelling area. Further necessary data (sedimentation rate, dry bulk density etc) should be required for the estimation of carbon stock to evaluate the major estuaries in Korea as potential carbon reservoirs in the coastal environment.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.2073-2077
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• 2009

지구 온난화의 영향으로 생각되는 이상기온이 세계각지에서 발생하고 있고, 우리나라도 최근 몇 년 동안 각지에서 집중호우에 의한 재해가 발생하고 있다. 이러한 자연재해는 모든 분야에서 심각한 영향을 미치고 있으며, 이중 산과 택지개발 및 도로공사 등에서 발생하는 토사는 하천, 저수지, 댐 및 하구를 빠르게 메우고 탁수환경을 지속시켜 수질악화와 오염원이 되며 저서생태계에 많은 영향을 미치고 있는 실정이다. 또한 토사는 농업용저수지와 수리구조물의 수명을 단축시키고, 하상을 높여 흐름을 방해하거나 변화시켜 하천의 범람을 유도하기도 한다. 이와 같이 토사는 토사농도변화에 따라 인명피해와 재산피해를 초래하고 있어 그 특징을 다각도로 분석 파악할 필요성이 있다. 본 연구에서는 토사의 농도와 분광반사특성의 상호관계를 알아보기 위해 원격탐사(RS)기법을 이용하였다. 탁수환경을 분광복사계(Li-1800)를 이용하여 미리 제작한 2개의 수조(흑색, 백색) 안 토사(실트질, 모래질)의 농도를 변화시켜 반사값을 측정하였다. 측정된 반사값을 이용하여 토사농도에 따른 분광반사 특성을 파악하였고, 토사 정보를 추정하는데 유용한 파장영역에 대해 검토, 고찰하였다.

• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.155-165
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• 2008

The purpose of this study was to evaluate the ecosystem of Yeongsan Lake using physical, chemical, and biological indicators. We evaluated the integrative ecosystem health using Lentie Ecosystem Health Assessment (LEHA) model, Qualitative Health Evaluation Index (QHEI) model, and chemical water quality. The models of LEHA and QHEI were modified as 10 and 7 metries attributes, respectively. Also, we analyzed bioaccumulation of total mercury on various fish tissues by method of U.S. EPA 7473 using Direct Mercury Analyzer (Model DMA-80). Model values of LEHA model averaged 19 (range: $14{\sim}26$, n=15), which indicated a "poor" condition, and had slightly spatial variations. Values of the QHEI in the all sites averaged 72, which were judged as a "fair" to "good" condition. The QHEI values varied from 48 (fair condition) to 99 (good condition) and showed large longitudinal gradients between the upper and lower reach. Conductivity and salinity were increased from the up-lake to downlake reach. Analysis of total mercury in fish tissues showed that levels of total Hg ranged between 0.002 and $0.087\;mg\;L^{-1}$ depending on the types of tissues. Overall, the ecosystem health in the Yeongsan Lake was judged as a "poor" and the effects of bioaccumulation on the fish tissues were minor. Therefore, it is necessary to keep an efficient management for the lake environment to maintain their ecological health.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.1
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• pp.50-61
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• 2010

This study was carried out to find out the way to build a comprehensive wetland ecosystem database using the technique of remote sensing and Geographic Information System. A Landsat TM image (taken in Oct. 30, 2002), Kompsat-2 images (Jan. 17, 2008 & Nov. 20, 2008), LiDAR(Mar. 1, 2009) were used for the primary source for the image analysis. Field surveys were conducted March to August of 2009 to help image analysis and examine the results. An actual wetland vegetation map was created based on the field survey. Satellite images were analyzed by unsupervised and supervised classification methods and finally categorized into such classes as Phragmites australis community, mixed community, sand beach, Scirpus planiculmis community and non-vegetation intertidal area. The map of wetland productivity was developed based on the productivity of Phragmites australis and the relationship to the proximity of adjacent water bodies. The developed 3 dimensional wetland map showed such several potential applications as flood inundation, birds flyway viewsheds and benthos distribution. Considering these results, we concluded that it is possible to use the remote sensing and GIS techniques for producing wetland ecosystem spatial database and these techniques are very effective for the development of the national wetland inventory in Korea.