Transfer of 65Zn from sediments by marine polychaete worms

摘要: Silty marine sediments spiked with 65Zn lose only small fractions of their radioactivity when exposed to slowly flowing seawater for several weeks. However, polychaete worms (Nereis diversicolor), burrowing through the sediment, cause losses 3 7 times higher than in sediment without worms. Long-term experiments on uptake and loss by Hermione hystrix indicate that 60 or more days exposure are required this worm approach steady state sediment. Biological half-life estimates accumulated from H. extremely variable (52 197 days), depending loss-time interval chosen calculation. Following 5 16 cm3 radioactive N. diversicolor individuals contained an average 0.2% total When these were transferred non-radioactive biological averaged 14 17 during period Day 15. Based experimental results, it is estimated a population could annual 3% upper 2 cm hypothetical estuary.