• 한국물환경학회지
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• 제24권2호
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• pp.195-200
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• 2008

To analyze the riverine microbial community structure, genetic fingerprints and ecological indexes such as species abundances, diversity, evenness, dominance of targeted rivers in Gyeonggi Province were acquired and evaluated using terminal restriction fragment length polymorphism (T-RFLP) technique. Genetic fingerprinting technique such as T-RFLP, which is able to show the microbial community clearly unlike traditional culture-dependent techniques, was thought to be useful to analyse the riverine microbial ecosystem under various factors. Riverine ecosystem evaluation using visible organisms would give biased results with time, targeted organism and researcher. But, T-RFLP, which can exclude the subjected biases such as culture condition and identification, would be an option to understand natural ecosystem by including the microorganisms that defy culture but perform important functions.

• 한국환경복원기술학회지
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• 제9권4호
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• pp.1-12
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• 2006

The usages of urban riverine areas for the Gapchoen and Yudungcheon in Daejoen City were evaluated by analyzing riverbed characteristics and water quality and by surveying the status of the floodplain usage including questionnaires of people visiting the rivers. Both rivers appear to be stable with insignificant bed changes as the riverbeds are dominated by gravels. Water qualities of both rivers have been improved significantly over the past decade although there are quite large seasonal fluctuations, which is common in most rivers in Korea. The results of floodplain usage analyses show that Gapcheon is dominated with static uses (>70%) such as promenades and resting facilities, while Yudungcheon by dynamic uses (>44%) such as sports facilities. Overall, both rivers require better plans for riverine area usage management considering a balance between the dynamic uses and the static uses such as natural observation places for education and habitats for birds and fish in the rivers. The questionnaire survey results indicate that overall the present status of both rivers are satisfactory and that water quality improvement is one of the key factors to enhance the value of the riverine areas. Future river restoration should be conducted by taking into account the characteristics of urban rivers in harmony with surrounding natural sceneries.

• Fisheries and Aquatic Sciences
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• 제8권3호
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• pp.167-176
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• 2005

Atmospheric deposition and riverine waters were sampled throughout a year, to estimate the loading fluxes of polycyclic aromatic hydrocarbons (PAHs) into the Masan Bay and its vicinity, Korea. Atmospheric deposition fluxes of total PAHs in the surveyed area varied from 62.2 to 464 ${\mu}g/m^2/year$. Concentration of total PAHs in water samples from six rivers ranged from 34.6 to 239 ng/L. Contribution of the carcinogenic PAHs to the total PAHs occupied $38\%$ and $50\%$ for atmospheric deposition and river waters, respectively. Atmospheric deposition fluxes and water concentrations of PAHs were slightly low or moderate to those in locations from some countries. Correspondence analysis was used to investigate the loading characteristics of PAHs according to transport routes. Atmospheric deposition samples were corresponded to higher molecular aromatics of PAHs, while riverine water samples were associated with lower molecular weight of PAHs. The results indicate that the higher-molecular-weight PAHs can be primarily transported by atmosphere deposition and the lower-molecular-weight PAHs can be mainly contaminated by riverine discharge into the Masan Bay and its vicinity. Loadings fluxes of PAHs into the Masan Bay and its vicinity were 39.2 g/day via atmosphere and 10.3 g/day via rivers, showing that atmospheric input was about 4 times higher than riverine one. Therefore, in order to minimize the contamination burden of PAHs from terrestrial sources to the Masan Bay and its vicinity, the control and management of PAHs deriving from atmosphere will be necessary.

• 한국지역지리학회지
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• 제19권1호
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• pp.1-13
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• 2013

담양습지보호지역은 전남 담양군과 광주광역시 북구 일원에 지정되어 있으며, 그 면적은 $980,575m^2$이다. 본 연구의 목적은 담양하천습지를 세부 지형단위로 나누고, 각 지형단위에 대한 퇴적물을 분석하여, 하천습지를 이루는 단위 생태계를 세분화하는 것이다. 하천습지는 하도습지와 범람원, 구하도 습지로 구분할 수 있는데, 담양하천습지는 하도습지의 유형에 속한다. 하도습지의 세부 지형단위를 분류하기 위하여, 1단계로 항공영상을 획득하여 세부 지형단위를 분류하였으며, 2단계로 현지 연구를 통해 분류 내용을 수정 보완하였다. 본 연구에서 담양습지보호지역은 22개의 생태계 단위로 구분된다. 그들의 퇴적물의 물리적 화학적 특성은 공간적으로 다양하게 나타나는데, 이는 담양하천습지의 서식환경이 다양함을 보여주는 것이다. 본 연구의 결과를 바탕으로 담양하천습지보호지역을 보다 효율적으로 관리할 수 있는 전략을 세울 수 있을 것이다. 이를 위해 담양습지에 형성된 다양한 하천지형과 이들을 서식지로 하는 생물들 간의 관계에 대한 학제적 연구가 필요하다.

• 한국지구과학회지
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• 제42권4호
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• pp.425-444
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• 2021

Investigating the physical and chemical properties of riverine wetlands is necessary to understand their distribution characteristics and depositional environment. This study investigated the physical (particle size, color, and type) and chemical properties (organic, inorganic, and moisture contents) of sediments in Samrak wetland, located in the Nakdong River estuary area in Busan, South Korea. The particle size analysis indicated that the hydraulic conductivity values for the coarse grain and the mixture of coarse and fine grains ranged from 2.03 to 3.49×10^-1 cm s^-1 and 7.18×10^-3 to 1.24×10^-7 cm s^-1, respectively. In-situ water quality and laboratory-based chemical analyses and radon-222 measurement were performed on groundwater and surface water in the wetland and water from the nearby Nakdong River. The physical and chemical properties of Samrak wetland was characterized by the sediments in the vertical and lateral direction. The concentrations of chemical components in the wetland groundwater were distinctly higher than those in the Nakdong River water though the wetland groundwater and Nakdong River water equally belonged to the Ca-HCO₃ type.

• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.113-118
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• 2002

Vegetation and riverine structures were compared among urban and several semi-natural rivers by applying direct gradient analysis and ordination method. Urban rivers showed different species composition from the semi-natural ones. Species composition of semi-natural rivers depended on the geographical positions, such as the upstream, midstream, and downstream and on micro-topographies, such as the waterside, flooding bed, and embankment. Semi-natural rivers showed gentle change in micro-topography, whereas urban one did not so. Our restoration plan to improve the ecological quality of the degraded urban river by imitating semi-natural river was prepared based on those data.

• The Korean Journal of Ecology
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• 제25권4호
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• pp.247-252
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• 2002

Vegetation and riverine structures were compared among urban and several semi-natural rivers by applying direct gradient analysis and ordination method. Urban rivers showed different species composition from the semi-natural ones. Species composition of semi-natural rivers depended on the geographical positions, such as the upstream, midstream, and downstream and on micro-topographies, such as the waterside, flooding bed, and embankment. Semi-natural rivers showed gentle change in micro-topography, whereas urban one did not so. Our restoration plan to improve the ecological quality of the degraded urban river by imitating semi-natural river was prepared based on those data.

• Fisheries and Aquatic Sciences
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• 제13권3호
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• pp.236-243
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• 2010

Fecal sterols, nonylphenolic compounds (NPs), and polycyclic aromatic hydrocarbons (PAHs) were determined in surface water from Masan Bay and its adjacent rivers in February 2005. Concentrations of coporstanol (Cop), an indicator of fecal pollution, in surface water ranged from <10 to 13,853 ng/L, and concentrations of nonylphenol, the most toxic of the NPs, ranged from 10.2 to 481 ng/L, and concentrations of PAHs ranged from 8.61 to 223 ng/L. The concentrations of the compounds measured in this study were lower than or comparable to those at other locations in Korea and other countries. The contamination of Cop and PAHs in surface water was associated with the discharge from rivers passing through cities and/or industrial complexes. The NP contamination was associated with wastewater treatment plant (WWTP) effluents through outfalls as well as riverine discharge. Compared to ecotoxicological values, the concentrations of NPs from rivers, the mouths of rivers, and WWTP outfall areas exceeded guidelines, suggesting that hot spot areas may pose a potential risk to sensitive species.

• Journal of Ecology and Environment
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• 제30권3호
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• pp.251-255
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• 2007

Self-thinning was measured in Salix communities on Bam Island in Seoul at various age stages. $D^2H$ was used to estimate tree biomass, where D is stem diameter at breast height or 10 cm height for plants with height <1.5 m, and H is height. A log-log plot of density versus $D^2H$ and correlation analysis indicated a significant relationship between density and biomass with equation 'log $D^2H$ = -1.27 log N + 7.06'. This indicates that self-thinning affects biomass in the Salix community with -1.27 as the thinning coefficient. If we assume a thinning exponent -3/2, then the allometric coefficient of the equation, log w = a log $D^2H$ + b, is 1.18. This is much higher than that for any other species studied in Korea. There were statistically significant relationships between age and density and between age and basal area and these relationships suggest guidelines for transplantation of willows and for the assessment of Salix community restoration projects in riverine wetlands based on standard density, basal area, and age. The results of this study may also increase understanding of succession processes in Salix community restoration in riverine wetlands.

• 한국해양공학회지
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• 제25권2호
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• pp.113-119
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• 2011

The Korea navy has a vital national interest in maritime security. The national strategy for maritime security focuses on preventing terrorism, crime, and hostile acts in the maritime domain. This requires the development of high speed crafts for maritime security in the South Korea domain. This paper reviews the state of the art on the development of high speed craft internationally, including efforts by the U.S. navy, and analyses the riverine environment to operate high speed crafts in South Korea. This paper makes specific proposals for high speed craft such as their main dimensions, speed, endurance, hull structure material, propulsion system, and general arrangement and 3D shape. This paper was used in the generation of basic resources for future ROC (requirement of capability) of high speed crafts using an engineering methodology.