Spatial distribution of C values of organic matter in surface sediments off Saru River in northern Japan, one year after a flood event in 2006

Nagao, Seiya*; Irino, Tomohisa*; Aramaki, Takafumi*; Ikehara, Ken*; Katayama, Hajime*; Otosaka, Shigeyoshi; Uchida, Masao*; Shibata, Yasuyuki*

Radiocarbon, 52(3), p.1068 - 1077, 2010/08

https://doi.org/10.1017/S0033822200046142

This study discusses the effects of flooding on the spatial distribution of organic matter on the shelf region of off the Saru River, southern part of Hokkaido, Japan, on the basis of the C and C values. Surface sediments on the shelf were collected in August 2007, one year after the severe flood in 2006. Suspended particles and sediment of the Saru River were also collected in August 2007 and 2008. The C values of organic matter in the shelf sediments ranged from -665 to -77 per mil. The silt and clay sediments had C values of -240 to -77 per mil, but the sandy sediments ranged from -665 to -388 per mil. The values of particulate organic carbon in the Saru River are -292 to -247 per mil at normal flow conditions. These results indicate that surface soil with relatively older organic matter is deposited on the shelf region by the flooding event, and freshly-produced organic matter in sea surface is deposited after the flooding.