Bank and point bar morphodynamics in the Lower Jingjiang Reach of the Yangtze River in response to the Three Gorges Project

Geomorphic dynamics of alluvial rivers in response to upstream damming have substantial impacts on navigation, habitat protection, and channel stability. The purpose this study was determine how flow sediment regimes, meander characteristics affect the morphological adjustment bends Lower Jingjiang Reach (LJR) before after Three Gorges Project (TGP). Based detailed field measurements hydrological topographic datasets from 1991 2016, banks point bars morphodynamics 12 continuous LJR were comprehensively analyzed. Point mainly experienced a net deposition TGP operation, but substantially deteriorated with erosion rate 4.6 million m3 yr−1 post-TGP periods (2003–2016), heads margins general pattern bends. most significant changes occurred 2006–2011, indicating delayed evolution damming. Detailed observations suggested that medium discharges (16,000–18,000 s−1) contributive shaping morphology In addition, we revealed importance supply deformation LJR, driven by exchange over bars, more planform tended occur high sinuosity (>2.0) relationship between manifested through geometric range bars. adjustments highly curved or compound conducive cause deflections, leading form concave-bank operation.