From the headwater to the delta: A synthesis of the basin-scale sediment load regime in the Changjiang River

Abstract

Highlights 23 1. We provide a comprehensive synthesis of basin-scale behavior of sediment 24 load regime in the Changjiang River. 25 2. Sediment loads have declined to insignificant quantities at majority of 26 gauges. 27 3. Dramatic sediment connectivity and source-to-sink changes are identified.

Declining Sediment Discharge in the Yangtze River From 1956 to 2017: Spatial and Temporal Changes and Their Causes

“…For example, Lake Poyang experienced a shift from sediment deposition to erosion in 2000, which was partly associated with the increased lake discharge due to the wider and deeper outflow channel of the lake created by intensive sand mining activities (Lai et al., 2014; Yao et al., 2019). Due to the above challenges, extracted sediment by mining has been normally excluded from sediment budget analysis of the Yangtze River in previous studies (e.g., Guo et al., 2019), but more studies are needed to address this scientific question in the future.…”

“…CWRC conducted measurements in most stations using widely accepted methods, but the observations at a few stations were performed by provincial Hydrology and Water Resources Survey Bureau. These data have been widely used in many studies in the past two decades (e.g., Guo et al., 2019; H. Wang et al., 2011; K. Xu et al., 2009; Z. Yang et al., 2006). The data are subject to well‐established quality control protocols by CWRC, but uncertainties or errors associated with it are not reported by the measurement agencies.…”

“…CWRC conducted measurements in most stations using widely accepted methods, but the observations at a few stations were performed by provincial Hydrology and Water Resources Survey Bureau. These data have been widely used in many studies in the past two decades (e.g., Guo et al, 2019;H. Wang et al, 2011;K.…”

The Ayeyarwady River (Myanmar): Washload transport and its global role among rivers in the Anthropocene

“…The Yangtze also experienced an enormous decrease in annual sediment load due to human impacts such as dams [ 41 , 42 ]. Currently, its total suspended sediment load is estimated to have been decreased to merely 123 ± 20.5 Mt yr -1 [ 43 ]. However, these results do not discriminate between washload and sand in suspension as separated populations of the total suspended load.…”

Regime shifts in the Changjiang (Yangtze River) Estuary: The role of concentrated benthic suspensions

“…After dredging operations, the ETM shifted 10-15 km upstream and became a wide turbidity zone between CS2 and CS8 (Jiang et al, 2013). The maximum SSC near the bed increased from several to tens kg/m 3 (Jiang et al, 2013;Wan and Zhao, 2017;Lin et al, 2020), although the sediment supply from the Changjiang River declined by 70% (Guo et al, 2019). However, the changes in SSC profiles remain unclear.…”