2023 Volume 79 Issue 25 Article ID: 23-25010
Diatoms play the main role as primary producer, in tidal flat ecosystems, which have high biological production. Diatoms requires silicon as essential nutrient. Since diatoms in tidal flats mainly obtain dissolved silicon (DSi) loading from a river, it is important to accumurate information about DSi dynamics. In this study, we conducted fieldworks on the basin of Zuibaiji river and evaluated the DSi supply into Imazu tital flat(S0), DSi traping or supply by a reservoir and a sewage treatment plant(T1, S1, respectively). S0 and T1 were estimated as 10.4 ton, and 0.57 ton in December 2022, respectively. It is considered that diatom production and sedimentation to bottom layer in the reservoir was main factor for DSi traping. S1 was also estimated that 2.7 ton of DSi were supplied in December 2022. It is indicated that the reservoirs and the sewage treatment plants have non-regligible influence to DSi supply into tital flats.