Abstract. The significance of biogenic silicon (BSi) pools as a key factor for the control of Si fluxes from terrestrial to aquatic ecosystems has been recognized since decades. However, while most research has been focused on phytogenic Si pools, knowledge on other BSi pools is still limited. We hypothesized different BSi pools to influence short-term changes of the water soluble Si fraction in soils to different extents. To test our hypothesis we took plant (Calamagrostis epigejos, Phragmites australis) and soil samples in an artificial catchment in a post-mining landscape in the state of Brandenburg, Germany. We quantified phytogenic (phytoliths), protistic (diatom frustules and testate amoeba shells) and zoogenic (sponge spicules) Si pools as well as Tiron extractable and water soluble Si fractions in soils at the beginning (t0) and after ten years (t10) of ecosystem development. As expected the results of Tiron extraction showed, that there are no consistent changes of the amorphous Si pool at Chicken Creek as early as after ten years. In contrast, compared to t0 we found increased water soluble Si and BSi pools at t10, thus we concluded BSi pools to be the main driver of short-term changes of water soluble Si. However, because total BSi represents only small proportions of water soluble Si at t0 (