Temporal change in elemental composition of sinking particles in the eastern Japan Sea

Otosaka, Shigeyoshi  ; Oku, Shunsuke*; Minami, Hideki*; Minakawa, Masayuki*; Noriki, Shinichiro*

Many researchers pointed out that decadal change in deep-sea circulation in the Japan Sea are strongly related with the global climate change. However, little is known about changes in fluxes and elemental composition of sinking particles in the sea. In this study, we assessed temporal changes in elemental composition of sinking particle in the Japan Sea by comparing results of a sediment trap experiment in middle 1980s with those in end of 1990s. The result indicated that (1) the contribution of Asian dust in sinking particles decreased significantly, (2) horizontal transport of re-suspended particles from the slope regions was weakened, and (3) there was no significant increase in vertical transport of anthropogenic heavy metals to the interior of the Japan Sea.