ALGAL ORGANIC LOAD FOR THE DOWN REACH RELATED TO THE STABILITY OF STREAMBED IN THE TAMA RIVER

Abstract

 The amount of algal organic load in the stream assumed with length of 1.5 km, width of 20 m, and slope of 1/300 on the study site (Nagata) in the Tama River, was simulated by using expressions of change in algal biomass during biofilm development, and the correlation between the percent tearing-off of algal community and their biomass. It was conducted under three conditions of stone size distribution (stable area: 100%, 0%, 72% in Nagata) and several conditions flood frequency. When flood frequency is low and/or when the stability of streambed is high, the amount of algal organic load for down reach in the stream is estimated significantly high.