Vertical inventories and fluxes of 210Pb, 228Ra and 226Ra at southern South China Sea and Malacca Straits

Inventories and fluxes of 210Pb, 228Ra and 226Ra were determined in sediment cores collected at nine stations covering of the southern South China Sea and Malacca Straits with the thickness of water column between 42 and 83 m depth. The inventories of 210Pb, 228Ra and 226Ra were calculated range from 0.15-2.55 Bq cm-2, 0.05-0.40 Bq cm-2 and 6.83-83.63 Bq cm-2, meanwhile the fluxes ranged from 0.005-0.079 Bq cm-2 yr-1, 0.009-0.048 Bq cm-2 yr-1 and 0.003-0.037 Bq cm-2 yr-1, respectively. The results show that the highest inventories and fluxes for 210Pb, 228Ra and 226Ra were found at station WC 01 and EC 05. Because there are additional sources of 210Pb, 228Ra and 226Ra, where water transport will brings more dissolved isotopes, influence of the transportation and deposition of suspended particles, fast rate of regeneration and greater production of those radionuclides and others. (author)