• Journal of Environmental Impact Assessment
• /
• v.6 no.1
• /
• pp.151-160
• /
• 1997

The Yangyang Pumped Storage Power Plant is being constructed by Korea Electric Power Corporation in Namdae-Chun River, Korea. The Yangyang Pumped Storage Power Plant has 1000MW capacity with upper reservior, lower reservior, hydrauric tunnel and underground power plant facilities. But NGO(Non Governmental Groups) and residents are worried about the power plant construction because of some problems, as follows. (1) Namdae-Chun River is principal salmon returning river in Korea. (2) Namdae-Chun River is main water supply source of the Yangyang country. So, brief explanation of Environmental Impacts Assessment executed by Korea Electric Power Corporation, main environmental impacts and countermeasures will be introduced.

• Journal of Korean Society on Water Environment
• /
• v.28 no.3
• /
• pp.418-425
• /
• 2012

Dam construction in a river can change its hydrological pattern and trap sediments, which results in ecological changes in the downstream. It is a common phenomenon in the downstream of dams to have decreased sediment flow and increased periphyton. Artificial floods and sediment application are suggested as mitigation practices in order to simulate natural process of flood; transporting sediment and sloughing periphyton off. In this study the effects of artificial floods on periphyton were examined by applying sand artificially and discharging water from a dam (Yangyang Dam, Korea). The study area has been suffering from turbidity problems caused by shore erosion of the dam. The accumulation of inorganic sediments and increase of periphyton on the river bottom are the major factors of habitat deterioration in the downstream reaches. Artificial flood and artificial addition of sand was performed in summer and the effects were measured. Piles of applied sands were washed off easily by discharge and it enhanced the periphyton sloughing effect. The removal efficiency of periphyton was 50 ~ 80% within the 2 km reach from the dam. In conclusion artificial floods and sand application can be a good mitigation measure for the habitat rehabilitation after a dam construction in streams.

• Korean Journal of Ecology and Environment
• /
• v.47 no.spc
• /
• pp.57-65
• /
• 2014

Spatial and temporal distributions of zooplankton were measured in an oligotrophic pumped storage-type hydroelectric reservoir which was composed of two reservoirs exchanging water daily, with water going up at night and going down during the day. Repetitive diel disturbance of the water column can be a unique feature of this reservoir system. Chl-${\alpha}$ concentration was highest in the early winter season. Phytoplankton density was lower in summer monsoon due to high flushing rate on rainy days. The zooplankton density was higher in the smaller upper reservoir possibly due to lower fish density in the upper reservoir. In the seasonal variation a time gap was observed between the phytoplankton bloom and the zooplankton bloom (particularly a rotifer, Keratella cochlearis). It is likely to that Keratella production is partially supported by heterotrophic food sources than phytoplankton. The dominance of a mixotrophic dinoflagellate (Peridinium bipes f. ocultatum) might have complicated the trophic relationship between phytoplankton and zooplankton. Our results provide some ecological information of zooplankton community in a highly disturbed alpine reservoir ecosystem relying on mostly allochthonous organic matter.