Author(s): Hyoseop Woo; Ji-Sung Kim; Kang-Hyeon Cho; Hyeong-Jin Cho
Linked Author(s): Hyoseop Woo, Ji-Sung Kim
Keywords: Sand bars; Vegetation recruitment; Shear stress; Groundwater table; Dam; Flow and sediment regime
Abstract: Hahoe Village, a historical and cultural village located on the upper Nakdong River in Korea, and registered as World Cultural Heritage by UNESCO, is more distinguished when two large sand bars in the river near the village remain “pure white” without vegetation on their surfaces. Two dams, constructed 25-30km upstream several dozen years ago, have completely modified the flow and sediment regimes downstream, causing continuous vegetation recruitment and establishment on the once ‘naked' two sand bars in the river. Possible causes for the vegetation recruitment are identified in this study using the comparison of relevant aerial photos, field investigations and hydraulic analyses. Governing factors of vegetation recruitment and establishment on the sand bars are the bed shear stress and flow intensity during floods, and the groundwater table below the sand bars. It was found that progress of the vegetation recruitment and establishment on the sandbars can be estimated largely using the distribution of the river-bed shear stress acting on them.
Year: 2011