Research progress on impact of damming and impoundment on the migration process of riverine reactive silicon

Abstract

[Objective] Reactive silicon is irreplaceable in certain biological structures, thereby influencing primary productivity and ecosystem stability. River dam construction profoundly alters the biogeochemical processes of nutrients in water, constraining river hydrological processes and ecosystem evolution. It is necessary to improve the understanding of the biogeochemical cycle of silicon in rivers through dam construction. [Methods] Based on a review of relevant studies, the migration and transformation mechanisms of riverine reactive silicon were taken as breakthrough points, with a focus on the retention effects of damming and its ecological impacts, the migration mechanism of reactive silicon after damming, and the biogeochemical processes of reactive silicon under specific damming patterns. [Results] Damming increased the retention of riverine reactive silicon, [Results]ing in negative ecological effects such as changes in biological community structure. Weakened rock weathering, intensified sedimentation and biological uptake and transformation, and the evolution of stratified density currents were key factors influencing reactive silicon migration, but the importance of each factor varied across different river regions. In rivers with cascade dams, the environmental behavior of reactive silicon was regulated by multiple complex pathways. The “reservoir-in-reservoir” effect caused by the construction of ecological regulating dams might alter key processes driving the reactive silicon cycle. [Conclusion] A comprehensive understanding of the specific mechanisms by which damming affects reactive silicon still requires further research. Future research is recommended to focus on dynamic monitoring and model development, multidimensional ecological impact assessments, mechanisms of stratified density currents, cross-regional comparisons, and the environmental behavior of reactive silicon under different operation patterns. The result deepen the understanding of the migration and transformation processes of riverine reactive silicon affected by dam construction and can provide guidance for the ecological management of river damming.

Keywords

riverine reactive silicon / damming and impoundment / migration and transformation / ecological regulating dam / stratified density current / biogeochemical process / influencing factors / research progress