River system in Japan from a landscape ecological aspect

The objective of this study was to elucidate characteristics associated with rivers by classification of major rivers in Japan into sereral types based on riparian conditions.As the results of principal compoent analysis(PCA) with use of parameters reflecting forms and artificial alterations of respective rives,four major components such as“comprehensive riparian size”,“intactness of water front”,“continuity of streams” and “silmplicity of landform in river basin”were extracted.Subsequently,cluster analysis was performed based on principal component scores,leading to succesful classification of major rivers into 6 types.These findings disclosed that(1) the extracted principal components provide effective viewpoint for classification of rivers;(2) distribution of respective classes indicates are properties;and (3) the emplyed quantitative procedures were found effective for classification of major rivers.