• Water Engineering Research
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• v.1 no.4
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• pp.299-307
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• 2000

The method for estimating the minimum instream flows required for the riverline aesthetics, proposed by the Kim et al.(1996), has been applied to the main channel reach of the Keum river basin in Korea. To determine the minimum instream flows for eight main reaches at Keum river basin, six representative stations have been selected. This paper provides an analysis of influence on the riverline aesthetics, which is affected by change of physical components of river, by using the survey-based quantification method. The developed questionnaire based on the literature, and submitted to the 326 people who visited an each representative station. This surveying had been implemented in three times at each representative station and we had been selected a different flowrate at each implementation. The results of this analysis and survey have produced the relationship between the variation of physical components and riverline aesthetics. Survey results bout the flow comparison are summarized as follows. At the view of riverline aesthetics, most of the respondents re sensitive at the change of the flow velocity and they prefer high water level to low water level. Moreover whole respondents prefer to abundant stream flows and moderate flow velocity. The minimum flows for riverline aesthetics is estimated at each representative station by using the survey-based quantification method and the estimated results of some representative station are greater than mean monthly flow at each station. The result of the analysis appears that establishing minimum instream flows for riverline aesthetics is not only a technical problem but a legal problem. Therefore in the case of establishing the instream flows in the river, the estimated results have to be considered as relative standard.

• Journal of Wetlands Research
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• v.23 no.2
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• pp.154-162
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• 2021

The naturally opened Han river estuary is a place where the flows of the Han river, Imjin river, Yaesung river meet with West Sea of Korea, so the hydrodynamic mechanism(Impact-Response) structure of Han river estuary is complex. Continuous observation and measurement due to the morphological characteristics at the estuary are required to maintain the estuary environment and river management facilities. However, the Sannam wetland(the study area) is in the military operation area. Therefore, Sannam wetland has the limited access under the control from military office. In 2020, there had a natural disaster due to flooding in August and COVID-19, and it made a survey hard. The noncontact survey technique, the analysis of LANDSAT images at Sannam wetland, was applied to analyze riverbed fluctuation and morphological transformation around Sannam wetland. LANDSAT images obtained from EarthExplorer, USGS and analyzed by QGIS. The analysis was performed based on the area and the distance near Sannam wetland. As a result, an erosion was happened on the downstream of the study area, and the upstream of the study area did not have any serious sediment transport. Considering the resolution of LANDSAT images, this noncontect survey technique is applicable to manage the study area. From the analysis of LANDSAT images, it is assumed that the tidal effect is greater than the inflow from the upstream. The pattern change of tidal response causes the damage of the river facilities near the Hangang river estuary.