2007年台風9号出水時における多摩川の土砂・栄養塩・有機物負荷特性

抄録

The purpose of the present study is to clarify the suspended-sediment, nutrient and carbon transports in the Tama River flowing into Tokyo bay in the large flood event caused by the attack of typhoon no. 0709. In the field measurement, we have monitored continuously the turbidity and conductivity using optical and electrical sensors with wipers and installed an automatic water sampler to collect the river water under hydrological events. The observed results indicate that the rating curves between the above-described transports and discharge in the large-scale flood are quite different in those in medium- and small-scale floods. In the large flood event, the suspended sediment, T-P and COD transports reach the amounts for the 6.6, 1.7 and 2.6 years, respectively, showing that the flood event due to the attack of typhoon no. 0709 has significantly environmental impact on water qualities of Tokyo Bay.