• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.258-264
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• 2018

A study was performed to analyze the biochemical composition (moisture, protein, fat, ash, salt value, iron, calcium and phosphorus) of raw and salted hilsa. Pure (with less than 1% impurities) and clean dry salt was used (fish weight : salt weight = 3 : 1) for salting the hilsa. The nutrients values of the hilsa from two different regions were significantly (p < 0.05) varied. The biochemical compositions were also different before and after the processing of the hilsa. Riverine hilsa contains relatively more moisture ($57.79{\pm}0.51%$) and protein ($15.65{\pm}0.50%$) than marine hilsa. Fat ($16.39{\pm}0.51%$) and salt ($1.80{\pm}0.14%$) contents are higher in marine hilsa; whereas the ash ($7.88{\pm}0.35%$) content was higher in the riverine hilsa. Minerals like iron ($4.92{\pm}0.32mg/100g$) and calcium ($480.02{\pm}6.73mg/100g$) remain in large amounts in the marine hilsa, but the phosphorus ($112.36{\pm}4.40mg/100g$) content remains at a high level in the riverine hilsa. In addition, the protein (raw condition, $18.54{\pm}0.46%$, riverine; $17.12{\pm}0.42%$, marine and salted condition, $32.54{\pm}0.5%$, riverine; $27.31{\pm}0.48%$, marine) and fat (raw condition, $15.41{\pm}0.46%$, riverine; $19.07{\pm}0.51%$, marine and salted condition, $11.58{\pm}0.39%$, riverine; $13.6{\pm}0.55%$, marine) contents were higher in the abdominal region of the riverine and marine hilsa both in the raw and salted conditions than in the head and caudal region.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.463-476
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• 2014

The riverine wetlands located in the riverside bring about social conflicts through confrontation between flood control value through flood control project and ecological preservation value of riverine wetland. In this study, we identified the importance of both values through analysis of economic feasibility of flood control and ecological values of riverine wetland, and tried to suggest management plans for riverine wetland considering both of flood control safety and ecological preservation through these results. For this, we calculated the expected annual flood damage of Imjin River using the multi-dimensional flood damage analysis(MD-FDA), and calculated the total value of riverine wetland using the contingent valuation method(CVM) to estimate preservation value of riverine wetland. The result of the analysis shows that the Imjin River needs flood control project and the ecological preservation of riverine wetland is also important. Therefore, the establishment of the management plan for protecting riverine wetland is also needed. As a result, the Imjin riverine wetland was classified as the area where sedimentation continues to take place, and the flood water level to rise. On the basis of the analyzed results, it is judged that the Imjin River needs flood control for public safety and ecological consideration for ecosystem preservation in the river improvement project. So, the stepwise river improvement is desirable to protect riverine wetland and minimize ecosystem disturbance. The results is expected to be made good use as the basic study for establishment of institutional river management plans considering flood control project and riverine wetland preservation in the future.

• Journal of Korean Society on Water Environment
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• v.24 no.2
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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.

• Journal of the Korean association of regional geographers
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• v.19 no.1
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• pp.1-13
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• 2013

Damyang Wetland Reserve with $980,575m^2$ area is located in Damyang-gun, Jeonlanam-do and Buk-gu, Gwangju Metropolitan City. The purpose of this paper is to divide Damyang riverine wetland into several geomorphic units, to analyze their sediments, and to categorize small ecosystem units composing riverine wetland. Riverine wetlands are classified into three types such as riverbed-, floodplain-, and abandoned-channel-wetland, and Damyang riverine wetland belongs to riverbed-wetland type. In this paper to categorize small geomorphic units of riverine wetland, we divide small geomorphic units from aircraft images analysis, and modify and supplement them following field survey results. Damyang Wetland Reserve is categorized into 22 ecosystem units. That physical and chemical properties of their sediments are different spatially, implicate that inorganic environment of Damyang riverine wetland ecosystem is very extensive. On the basis of the results of this study, policymakers will be able to design a strategy which manage Damyang Riverine Wetland Reserve more effectively, and for them interdisciplinary researches on relationships between various fluvial landforms and various lifeforms inhabiting them in Damyang Riverine Wetland Reserve are required.

• Journal of Environmental Impact Assessment
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• v.20 no.1
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• pp.1-11
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• 2011

This study was carried out to suggest the baseline data necessary for vegetation restoration at riverine wetland within stream corridor. We used the prevalence index for wetland assessment by applying the method of weighted averages with index values based on five hydrophyte indicator status as defined by estimated probability occurred in wetland. We selected near nature and urbanized reach of Gap and Yanghwa streams as experimental site. Although two sites have some different disturbance and characteristics of watershed, they showed that similarity of vegetation community including three dominant species - Salix koreensis, Phragmites communis, Miscanthus sacchariflorus - was very high. But in case of Yanghwa stream, various kinds of emergent plants along wetted condition were distinctly occurred, resulted from difference of hydrological regime and substrate, etc. Degree of naturalness of vegetation at the sampled areas indicated that near nature area of Gap stream and all area of Yanghwa stream were fitted as riverine wetland, while urbanized area of Gap stream has changed into upland condition. In conclusion assessment system using prevalence index would be considered an effective method for evaluating of natural states of riverine wetland, but further integrated consideration of physical, hydrological, and biological factors of stream process, and also with considering the difference between those qualitative data of vegetation community.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.4
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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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• v.8 no.3
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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.

• Wind and Structures
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• v.26 no.6
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• pp.343-354
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• 2018

A realistic FEM structural model is developed to predict the behavior, load transfer, force distribution and performance of a riverine platform under earthquake and environmental loads. The interaction between the transfer plate and the piles supporting the platform is investigated. Transfer plate structures have the ability to redistribute the loads from the superstructure above to piles group below, to provide safe transits of loads to piles group and thus to the soil, without failure of soil or structural elements. The distribution of piles affects the distribution of stress on both soil and platform. A materially nonlinear earthquake response spectrum analysis was performed on this riverine platform subjected to earthquake and environmental loads. A fixed connection between the piles and the platform is better in the design of the piles and the prospect of piles collapse is low while a hinged connection makes the prospect of damage high because of the larger displacements. A fixed connection between the piles and the platform is the most demanding case in the design of the platform slab (transfer plate) because of the high stress values developed.

• Water for future
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• v.29 no.4
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• pp.161-176
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• 1996

Methods for determining the instream flow in the stream were explored and examined through careful reviews and evaluations of available literatures. Development of the instream flow estimation method is based on the reviewed results and methods which can be used within the acceptable levels.The newly-developed method was tested on the streams which require maintaining some riverine functions, such as the instream flow and river-management flow at the specific channel reach or representative station of the river. The riverine functions mainly considered in this study are the minimum flow, water quality conservation, fish habitat rehabilitation and conservation, riverine aesthetics, river navigation and recreation, and so on. As a result, the newly-developed instream flow estimation method is expected to be used effectively for determining the instream flow, which is necessary in order to maintain the natural or artificial riverine functions.

• Journal of the korean society of oceanography
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• v.35 no.1
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• pp.56-64
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• 2000

The importance of terrestrial organic matter as a food source for a brackish water clam Corbicula japonica was evaluated using stable carbon isotope ratios (${\delta}^{13}$C) in its tissues and potential food resources in an estuarine system of Youngil Bay, Korea. Suspended particulate organic matter (POM) had distinct ${\delta}^{13}$C values from riverine (-31.8 to -27.2%$_o$) to marine waters (-21.0 to -16.6%$_o$). Estuarine macroalgae had a wide ${\delta}^{13}$C range of -22.8 to -15.0%$_o$. The ${\delta}^{13}$C values of riverine POM were more negative than that of riverine phytoplankton (-26.5 to -24.2%$_o$) but similar to that of freshmarsh plant species (-29.1 to -27.5%$_o$ for Phragmites communis and -28.5 to -27.0%$_o$ for Salix gracilistyla), These ${\delta}^{13}$C values suggest that the POM transported by the Hyungsan River is predominantly of terrestrial origin rather than riverine autochthonous sources. The ${\delta}^{13}$C values of Corbicula japonica tissues (-28.7 to -27.2%$_o$) were most similar to values for riverine POM and freshmarsh plants. There was no significant difference in the isotopic composition of the clam individuals. The results indicate a predominant contribution of organic carbon derived from terrestrial and fresmarsh plant detritus to the diet of Corbicula japonica. Our results also confirm previous suggestion that terrestrial organic matter can be incorporated into estuarine food webs although its role is confined to the upper estuarine reaches.