蒲田川流域の地形学的特性に関する研究(1)

Abstract

The Gamata River is a tributary of the Jirtau River running into the bay of Toyama inJapan which is one of typical trential rivers and is transporting sediments of great amount fromthe desolated basin. The basin area of the Gamata River is approximately 98Km2 - The basinis located in the Japan North Alps and the elevation is approximately 1, OOOm to 3, OOOm.To study the mechanism of run off and sediment transport in such a desolated higher altitudebasin, it is necessary to disclose the characters of basin with the aid of geomorphological analysisand field observations of sediment characteristics. The present paper is a first report of thestudy and deals with the geomorphological approach to disclose the characters of streams in thisbasin, in which the order analysis of streams for not only the basin but the ten elementarybasins of 4th order, drainage density and texture ratio analysis, frequency analysis of streamlength and hypsometric curve analysis were made with the aid of quantitative analysis of watershedgeomorphology and the development of streams and method of analysis were considered.