| Title |
Effects of Sand Supply and Artificial Floods on Periphyton in the Downstream of a Dam (Yangyang Dam, Korea) |
| Authors |
박미숙 ( Mi Sook Park ) ; 이재용 ( Jae Yong Lee ) ; 정성민 ( Sung Min Jung ) ; 박창근 ( Chang Keun Park ) ; 장군 ( Kun Chang ) ; 김범철 ( Bom Chul Kim ) |
| Keywords |
Artificial flood; Removal efficiency of periphyton; Sediment; The Hoo stream; Yangyang Dam |
| Abstract |
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. |