Anthropogenic interference and climatic change control long‐term dissolved silicate variation in the Yellow River

Abstract Dissolved silicate (DSi) export from rivers is shaped by both natural processes and human activities. Using long‐term observations at Lijin station combined with chemical weathering and reservoir silicon cycling models, we reconstructed annual DSi fluxes and source‐sink dynamics in the Yellow River Basin since the 1980s. Chemical weathering inputs and terrestrial vegetation uptake have increased, whereas soil erosion has declined and reservoir retention has remained relatively stable in the 21 st century. Riverine DSi concentrations at Lijin have decreased significantly since 2000. This decline is primarily driven by enhanced vegetation uptake and reduced soil erosion, with increased precipitation and discharge likely contributing to dilution. In contrast, annual DSi fluxes exhibit strong interannual variability mainly controlled by river discharge. Overall, our results reveal a transition from predominantly natural regulation toward increasing human control of riverine silicon cycling.