『Abstract
samples obtained from sediment trap studies are exposed to a
variety of biases. One is the solubilization of particles in the
sampling jars. We examined the dissolved silicon concentrations
in the supernatants of sediment trap samples compiled during long-term
studies from the Northern North Atlantic and the Baltic Sea. Samples
originated from shallow depths (130-500 m) to depths close to
the seafloor (2000-3000 m). A considerable increase of the dissolved
silicon concentration due to the solubilization of biogenic particulate
silica (bPSi) at all depths was measured at time scales typical
for annual mooring deployments and sample analysis. During periods
of low bPSi flux more than 80% of the sedimented silicon can be
converted to the dissolved phase. On an annual basis the dissolved
fraction accounted for up to 60% of total sedimented bPSi during
single years. Median values vary between 13% and 30% and considerable
dissolution was encountered in the shallow as well as in the deep
sediment traps. Based on our data we conclude that the flux of
bPSi and quantities derived thereof are erroneous unless corrected
for the dissolved fraction. We therefore strongly recommend to
quantify the dissolved silicon in sediment trap samples and to
use these values for the correction of the particulate silicon
flux.
Keywords: sediment traps; sedimentation; biogenic silicon flux;
silicon dissolution』
1. Introduction
2. Material and methods
3. Results and discussion
4. Conclusion
Acknowledgements
References