Fundamental Study on Suspended-Sediment Transport of Main Rivers Flowing Into Tokyo Bay

Abstract

Kyosuke SHIGETA, Yasuo NIHEI, Ayako SAKAI and Satoshi OOTSUKATo examine the suspended-sediment transport from inland to costal areas in Tokyo Bay, we have monitored the suspended-sediment transport in main rivers flowing into Tokyo Bay, which are the Edo, Ara, Tama, Naka and Sumida Rivers. In the field surveys, we have installed an optical sensor for measuring turbidity and water samplers to measure the sediment concentration and particle size under flood flow conditions. The observed results reveal that the fine sediments of particles less than 71 μm are mainly transported in the main rivers under several flood flow conditions. The transports of finer and coarser sediments are relatively dominant in the Ara River and the Edo and Tama Rivers, respectively.

Occurrence and partition ratios of radiocesium in an urban river during dry and wet weather after the 2011 nuclear accident in Fukushima

“…The radiocesium concentrations in the particulate phase were corrected as follows ( The negative correlation of apparent K d with [SS] during wet weather could be explained 236 by the increase in particle size with increasing [SS] during heavy rain (Shigeta et al, 2008). 237…”