@article{oai:niigata-u.repo.nii.ac.jp:00028398, author = {権田, 豊 and 岡崎, 達也 and 西井, 洋平 and 川邉, 洋}, issue = {1}, journal = {新潟大学農学部研究報告, 新潟大学農学部研究報告}, month = {Sep}, note = {本研究では、山地河川が本来有している特性を明らかにすることを目的に、河川環境の重要な構成要素であるStep-Pool構造に焦点をあて、流域特性・降雨特性の異なる, 新潟県および三重県の8つの山地河川、合計35調査プロットにおいて、Step-Poolの形状と河床勾配や流路幅といった河道条件の計測結果を行った。調査結果を用いて、実河川におけるStep-Pool構造の形状及び分布特性やStepの成因、形成流量について考察した。その結果、河床勾配、低水路幅、Step 構成礫の礫径の3つは、Step-Poolの形状や分布特性を特徴付ける重要なパラメータであることがわかった。今回の調査結果を基に、地形図などから容易に調べることが可能な流域面積や勾配を用いて、山地河川に存在するStep-Pool構造のスケールを表す関係式を構築した。, In this study, the relationship between channel geometry and step-pool morphology are discussed. The channel geometry, i.e., the channel gradient, channel width, the step-pool dimensions, size and number of step particle, etc., were surveyed at 35 study reaches of eight small basins in Japan. The results show that the channel gradient, channel width, and particle size have various implications for the step-pool geometry. With regard to the longitudinal profile of a step, the relationship between the channel geometry, step wavelength and step-step drop differs from that reported by previous studies at high-gradient reaches (> 0.15 gradientA). The channel width and particle size are important variables aff ecting the step wavelength and step-step drop. Step width, which is the transverse profile of a step, is about 6 times the mean size of the rocks that form the step, and it is probably controlled by the particle size and channel width. The pool geometry is likely to be related to the channel gradient, discharge, and particle size. The characteristics of the distribution and the geomAetry of the step-pool can be explained by three parameters (particle size, discharge, and channel gradient). Estimation formulae were developed, which estimate local average geometry of the step-pool with catchment area and channel gradient.}, pages = {67--93}, title = {山地河川におけるStep-Pool構造の形状及び分布特性}, volume = {61}, year = {2008} }