Dissolution rates of silica from diatoms decomposing at various temperatures

✍ Scribed by A. Kamatani

• Publisher: Springer-Verlag
• Year: 1982
• Tongue: English
• Weight: 506 KB
• Volume: 68
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00393146

✦ Synopsis

In a study of silica dissolution from diatoms, the rate coefficient (K) h -1 of raw diatom cells was estimated as 4 to 5 times smaller than that of the acid-digested siliceous skeletons. The dissolution rate coefficient at early stage (K1) can be predicted as a function of temperature (T ~ In K1 = a +fl T, where a is the frequency factor depending on the properties of diatom species, ranging from -7.35 to -10.38, and the temperature coefficient fl is 0.0833 for all species. Activation energies were calculated to be 1.37 to 1.38 Kcalmol -~. This equation suggests that the rate coefficient K~ increases by a factor of 2.27 for each 10 C ~ rise in temperature. This equation will also be applied to a new approach for the fate and behavior of biogenous silica settling through a water column by introducing the term temperature into a model. 4.9 x 10 -4 * These experiments were carried out under shaking condition (120 strokes min -1) ** The figures in parentheses show the length of apical axis in ~m (Kokubi, 1965; Yam@, 1977