Mechanism and ecological effect of river-transported silicon flux reduction
LIU Ming1, ZHI Chong-yuan1,2, LI Kai3
1, School of Life Sciences, Guizhou Normal University, Guiyang 550001, China; 2. Key Laboratory for Information System of Mountainous Area and Protection of Ecological Environment of GuiZhou Province, Guiyang 550001, China; 3. Bijie Longchangying Middle School of Guizhou Province, Guizhou, Bjie 551707, China
The mechanisms of river-transported silicon flux reduction are analyzed from several aspects including damming, diatom absorption and fixation, fishery, water eutrophication and hydrological changes; besides, the ecological effect of river-transported silicon flux reduction on river, estuary and inshore is evaluated. The results indicate that river-transported silicon flux reduction greatly impacts the geochemical cycle of silicon, resulting in an ecological imbalance. Diatom is a major factor responsible for the river-transported silicon flux reduction. The dissolved silicon in the water body of reservoir is taken up and utilized by diatom. Ultimately the silicon sedimentates and stores in the bottom of reservoir after the death of diatom, which leads to a lack of dissolved silicon in downstream river and ocean, and this brings about serious ecological effect on human beings.
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