A study of the diversity of natural topography in straight and meandering streams by the installation of groynes

Abstract

This study observed topographic changes resulting from installed groynes at straight and meander experimental test-beds (Shihwa wetland). Bed and edge changes were induced more with installation of groynes than without. In comparison of the installation angle of groynes, erosion was found in the case of 45° to the stream flow while deposition in the case of 135°. In the case of the installation shape of groynes, various topographic changes were found more with those of double bar type than those of one bar type. After that we applied them to a field test-bed (Geumdang Valley) to conduct a comparative analysis. We observed results of topographic change and biodiversity after more than one year from the installation of groynes at the field test area based on test-bed results. In the real stream, which minimized manmade elements, more forms of bed and edge of stream could be created only with the installation of groynes similar to the results of the test-bed. We observed that various topographic changes could form kinds of habitats of fishes and benthic invertebrates.