The magnitude of Si dissolution from diatoms at the sediment surface and its potential impact on P mobilization
Archiv für Hydrobiologie Volume 144 Number 4 (1999), p. 429 - 438
published: Mar 24, 1999
ArtNo. ESP141014404008, Price: 29.00 €
The magnitude of the influence of diatom-derived dissolved Si on the mobility of P at the sediment-water interface was investigated in eutrophic Lake Vesijärvi, southern Finland. The spring bloom, which consisted of small centric diatoms, depleted the Si from the water column ( <100 µg 1-1) and was followed by a sharp increase in the diatom numbers at the sediment surface and by a peak of dissolved Si in the sediment interstitial water. The diatom cells disappeared from the surface sediment on a time scale of weeks (5 % d-1). Calculations based on the cell numbers and on the Si deficit in the water column indicated that the dissolution of diatoms in the sediment surface layer may produce Si pulses high enough to influence the mobility of P.